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Cerebral hemodynamics have been quantified during exercise via transcranial Doppler ultrasound, as it has high-sensitivity to movement artifacts and displays temporal superiority. Currently, limited research exists regarding how different exercise modalities and postural changes impact the cerebrovasculature across the cardiac cycle. Ten participants (4 females and 6 males) ages 20–29 completed three exercise tests (treadmill, supine, and upright cycling) to volitional fatigue. Physiological data collected included middle cerebral artery velocity (MCAv), blood pressure (BP), heart rate, and respiratory parameters. Normalized data were analyzed for variance and effect sizes were calculated to examine differences between physiological measures across the three exercise modalities. Systolic MCAv was greater during treadmill compared to supine and upright cycling (p < 0.001, (large) effect size), and greater during upright versus supine cycling (p < 0.017, (large)). Diastolic MCAv was lower during treadmill versus cycling exercise only at 60% maximal effort (p < 0.005, (moderate)) and no differences were observed between upright and supine cycling. No main effect was found for mean and diastolic BP (p > 0.05, (negligible)). Systolic BP was lower during treadmill versus supine cycling at 40% and 60% intensity (p < 0.05, (moderate–large)) and greater during supine versus upright at only 60% intensity (p < 0.003, (moderate)). The above differences were not explained by partial pressure of end-tidal carbon dioxide levels (main effect: p = 0.432). The current study demonstrates the cerebrovascular and cardiovascular systems respond heterogeneously to different exercise modalities and aspects of the cardiac cycle. As physiological data were largely similar between tests, differences associated with posture and modality are likely contributors. [ABSTRACT FROM AUTHOR]

Background: The single-inhaler triple combination of beclometasone dipropionate, formoterol fumarate, and glycopyrronium (BDP/FF/G) is available for maintenance therapy of chronic obstructive pulmonary disease (COPD). Cardinal features of COPD are lung hyperinflation and reduced exercise capacity. TRIFORCE aimed to evaluate the effect of BDP/FF/G on lung hyperinflation and exercise capacity in patients with COPD. Methods: This double-blind, randomised, active- and placebo-controlled, crossover study recruited adults with COPD aged ≥ 40 years, who were hyperinflated and symptomatic, and were receiving mono- or dual inhaled maintenance COPD therapy. In the three treatment periods, patients were randomised to receive BDP/FF/G, BDP/FF, or placebo, each for 3 weeks, with a 7–10-day washout between treatment periods. Assessments included slow inspiratory spirometry (for resting inspiratory capacity [IC]) and constant work-rate cycle ergometry (for dynamic IC and exercise endurance time). The primary objective was to compare BDP/FF/G and BDP/FF vs. placebo for resting IC at Week 3. Key secondary objectives were to compare BDP/FF/G and BDP/FF vs. placebo for dynamic IC and exercise endurance time during constant work rate cycle ergometry at Week 3. Results: Of 106 patients randomised, 95 completed the study. Resting IC adjusted mean differences vs. placebo were 315 and 223 mL for BDP/FF/G and BDP/FF, respectively (p < 0.001 for both). Adjusted mean differences vs. placebo for the key secondary endpoints were: 245 mL for dynamic IC (p < 0.001) and 69.2 s for exercise endurance time (nominal p < 0.001) with BDP/FF/G, and 96 mL (p = 0.053) and 70.1 s (nominal p < 0.001) with BDP/FF. Differences between BDP/FF/G and BDP/FF for resting and dynamic IC were 92 and 149 mL (p < 0.01 for both). All three treatments were generally well tolerated, with 27.3%, 25.3% and 19.0% of patients reporting adverse events with BDP/FF/G, BDP/FF and placebo, respectively, all mild or moderate. Conclusions: In patients with COPD, BDP/FF/G provided significant and clinically relevant improvements vs. placebo and BDP/FF in static and dynamic hyperinflation, with an improvement vs. placebo in exercise endurance. Trial registration: ClinicalTrials.gov (NCT05097014), registered 27th October 2021. [ABSTRACT FROM AUTHOR]

Abstract Background The single-inhaler triple combination of beclometasone dipropionate, formoterol fumarate, and glycopyrronium (BDP/FF/G) is available for maintenance therapy of chronic obstructive pulmonary disease (COPD). Cardinal features of COPD are lung hyperinflation and reduced exercise capacity. TRIFORCE aimed to evaluate the effect of BDP/FF/G on lung hyperinflation and exercise capacity in patients with COPD. Methods This double-blind, randomised, active- and placebo-controlled, crossover study recruited adults with COPD aged ≥ 40 years, who were hyperinflated and symptomatic, and were receiving mono- or dual inhaled maintenance COPD therapy. In the three treatment periods, patients were randomised to receive BDP/FF/G, BDP/FF, or placebo, each for 3 weeks, with a 7–10-day washout between treatment periods. Assessments included slow inspiratory spirometry (for resting inspiratory capacity [IC]) and constant work-rate cycle ergometry (for dynamic IC and exercise endurance time). The primary objective was to compare BDP/FF/G and BDP/FF vs. placebo for resting IC at Week 3. Key secondary objectives were to compare BDP/FF/G and BDP/FF vs. placebo for dynamic IC and exercise endurance time during constant work rate cycle ergometry at Week 3. Results Of 106 patients randomised, 95 completed the study. Resting IC adjusted mean differences vs. placebo were 315 and 223 mL for BDP/FF/G and BDP/FF, respectively (p

Introduction: The upper body Wingate Anaerobic Test (WAnT) is a 30-smaximal effort sprint against a set load (percentage of body mass). However, there is no consensus on the optimal load and no differential values for males and females, even when there are well-studied anatomical and physiological differences in muscle mass for the upper body. Our goal was to describe the effects of load, sex, and crank position on the kinetics, kinematics, and performance of the upper body WAnT. Methods: Eighteen participants (9 females) performed threeWAnTs at 3%, 4%, and 5%of body mass. Arm crank forces, 2D kinematics, and performance variables were recorded during eachWAnT. Results: Our results showed an increase of ~49% effective force, ~36%peak power, ~5° neck flexion, and ~30° shoulder flexion from 3% to 5% load (P < 0.05). Mean power and anaerobic capacity decreased by 15%, with no changes in fatigue index (P < 0.05). The positions of higher force efficiency were at 12 and 6 o'clock. The least force efficiency occurred at 3 o'clock (P < 0.05). Sex differences showed that males produced 97% more effective force and 109% greater mean power than females, with 11.7%more force efficiency (P < 0.001). Males had 16° more head/neck flexion than females, and females had greater elbow joint variability with 17°morewrist extension at higher loads. Males cycled ~32%faster at 3%versus 5%WAnT load with a 65%higher angular velocity than females. Grip strength, maximal voluntary isometric contraction, mass, and height positively correlated with peak and mean power (P < 0.001). Conclusions: In conclusion, load, sex, and crank position have a significant impact on performance of theWAnT. These factors should be considered when developing and implementing an upper body WAnT. [ABSTRACT FROM AUTHOR]

Introduction: Inflammation and metabolic disorders of cardiomyocytes are undoubtedly important pathogenetic links in the development of coronary heart disease and its complications. Our study assessed the effect of various combined treatment regimens on cycle ergometry performance and plasma concentrations of pro- and anti-inflammatory interleukins in patients with stable effort angina, functional classes II-III. Materials and Methods: The clinical study included 120 patients diagnosed with coronary heart disease: stable effort angina, functional classes II-III, and 40 healthy participants who met the inclusion criteria. Further, four groups were randomly formed: a group receiving the standard treatment; a group receiving Mexicor for 10 days in addition to the standard treatment; a group receiving Mexicor and Phosphogliv for 10 days in an addition to the standard treatment; and a group receiving Mexicor and Polyoxidonium for 10 days in addition to the standard treatment. After the treatment, cycle ergometry performance and plasma concentrations of pro- and anti-inflammatory cytokines were assessed in the patients. Mathematical statistical analysis was carried out using Statistica 10.0 software. The statistical significance of differences between the qualitative indicators was assessed using the χ2 test. The results of the statistical analysis were considered statistically significant at p<0.05. Results: The combined treatment with using the above-mentioned pharmacological agents resulted in a statistically significant improvement in cycle ergometry indicators: Mexicor made it possible to increase the threshold load power by 43.0% and the total load power - by 70.3%. In the groups of patients with coronary heart disease who had received Mexicor and Phosphogliv or Mexicor and Polyoxidonium, there was an increase in the load duration by an average of 69.0% and in the rate-pressure product - by 25%, respectively. When analyzing the dynamics of plasma concentrations of pro-inflammatory cytokines, it was found that a statistically significant decrease in the concentrations of tumor necrosis factor-a, interleukin-1ß, interleukin-6 and interleukin-10 was registered only in the groups receiving Mexicor and Phosphogliv or Mexicor and Polyoxidonium in addition to the standard treatment. Conclusion: Applying the combined treatment regimens using Mexicor and Phosphogliv or Polyoxidonium results in the most effective improvement of the cycle ergometry performance and the dynamics of plasma concentrations of pro- and anti-inflammatory interleukins in patients with stable effort angina, functional classes II-III. [ABSTRACT FROM AUTHOR]

Abstract Background Older critically ill patients experience rapid muscle loss during stay in an intensive care unit (ICU) due to physiological stress and increased catabolism. This may lead to increased ICU length of stay, delayed weaning from ventilation and persistent functional limitations. We hypothesized that with optimal nutrition and early physical therapy acting in synergism, we can reduce muscle mass loss and improve functional outcomes. Methods This was a prospective, single blinded randomized, controlled single-center pilot study to compare the lean muscle mass (measured at bilateral quadriceps femoris using ultrasound) of older ICU patients at 4 time points over 14 days between the control and intervention groups. The control group received standard weight-based empiric feeding and standard ICU physiotherapy. The intervention group received indirect calorimetry directed feeding adjusted daily and 60 min per day of cycle ergometry. 21 patients were recruited and randomized with 11 patients in the control arm and 10 patients in the intervention arm. Secondary outcome measures included ICU and hospital mortality, length of stay, functional assessments of mobility and assessment of strength. Results Median age was 64 in the control group and 66 in the intervention group. Median calories achieved was 24.5 kcal/kg per day in the control group and 23.3 kcal/kg per day in the intervention group. Cycle ergometry was applied to patients in the intervention group for a median of 60 min a day and a patient had a median of 8.5 sessions in 14 days. Muscle mass decreased by a median of 4.7cm2 in the right quadriceps femoris in the control group and 1.8cm2 in the intervention group (p = 0.19), while the left quadriceps femoris decreased by 1.9cm2 in the control group and 0.1cm2 in the intervention group (p = 0.51). Conclusion In this pilot study, we found a trend towards decrease muscle loss in bilateral quadriceps femoris with our combined interventions. However, it did not reach statistical significance likely due to small number of patients recruited in the study. However, we conclude that the intervention is feasible and potentially beneficial and may warrant a larger scale study to achieve statistical significance. Trial Registration This study was registered on Clinicaltrials.gov on 30th May 2018 with identifier NCT03540732.

Background: Older critically ill patients experience rapid muscle loss during stay in an intensive care unit (ICU) due to physiological stress and increased catabolism. This may lead to increased ICU length of stay, delayed weaning from ventilation and persistent functional limitations. We hypothesized that with optimal nutrition and early physical therapy acting in synergism, we can reduce muscle mass loss and improve functional outcomes. Methods: This was a prospective, single blinded randomized, controlled single-center pilot study to compare the lean muscle mass (measured at bilateral quadriceps femoris using ultrasound) of older ICU patients at 4 time points over 14 days between the control and intervention groups. The control group received standard weight-based empiric feeding and standard ICU physiotherapy. The intervention group received indirect calorimetry directed feeding adjusted daily and 60 min per day of cycle ergometry. 21 patients were recruited and randomized with 11 patients in the control arm and 10 patients in the intervention arm. Secondary outcome measures included ICU and hospital mortality, length of stay, functional assessments of mobility and assessment of strength. Results: Median age was 64 in the control group and 66 in the intervention group. Median calories achieved was 24.5 kcal/kg per day in the control group and 23.3 kcal/kg per day in the intervention group. Cycle ergometry was applied to patients in the intervention group for a median of 60 min a day and a patient had a median of 8.5 sessions in 14 days. Muscle mass decreased by a median of 4.7cm2 in the right quadriceps femoris in the control group and 1.8cm2 in the intervention group (p = 0.19), while the left quadriceps femoris decreased by 1.9cm2 in the control group and 0.1cm2 in the intervention group (p = 0.51). Conclusion: In this pilot study, we found a trend towards decrease muscle loss in bilateral quadriceps femoris with our combined interventions. However, it did not reach statistical significance likely due to small number of patients recruited in the study. However, we conclude that the intervention is feasible and potentially beneficial and may warrant a larger scale study to achieve statistical significance. Trial Registration: This study was registered on Clinicaltrials.gov on 30th May 2018 with identifier NCT03540732. [ABSTRACT FROM AUTHOR]

Heightened sensation of leg effort contributes importantly to poor exercise tolerance in patient populations. We aim to provide a sex‐ and age‐adjusted frame of reference to judge symptom's normalcy across progressively higher exercise intensities during incremental exercise. Two‐hundred and seventy‐five non‐trained subjects (130 men) aged 19–85 prospectively underwent incremental cycle ergometry. After establishing centiles‐based norms for Borg leg effort scores (0–10 category‐ratio scale) versus work rate, exponential loss function identified the centile that best quantified the symptom's severity individually. Peak O2 uptake and work rate (% predicted) were used to threshold gradually higher symptom intensity categories. Leg effort‐work rate increased as a function of age; women typically reported higher scores at a given age, particularly in the younger groups (p < 0.05). For instance, "heavy" (5) scores at the 95th centile were reported at ~200 W (<40 years) and ~90 W (≥70 years) in men versus ~130 W and ~70 W in women, respectively. The following categories of leg effort severity were associated with progressively lower exercise capacity: ≤50th ("mild"), >50th to <75th ("moderate"), ≥75th to <95th ("severe"), and ≥ 95th ("very severe") (p < 0.05). Although most subjects reporting peak scores <5 were in "mild" range, higher scores were not predictive of the other categories (p > 0.05). This novel frame of reference for 0–10 Borg leg effort, which considers its cumulative burden across increasingly higher exercise intensities, might prove valuable to judging symptom's normalcy, quantifying its severity, and assessing the effects of interventions in clinical populations. [ABSTRACT FROM AUTHOR]

Purpose: Submaximal exercise tests (SET) are an easier to conduct and less physically demanding alternative to cardiopulmonary exercise testing for assessment of pre-operative fitness. Assessment of heart rate recovery (HRR) following SETs offers an easily obtained marker of vagal reactivation and sympathetic withdrawal and therefore provides an indication of an individual’s fitness. This study sought to assess the reproducibility of HRR across different workloads and modalities of SET. Methods: Thirty-four healthy volunteers were recruited to undergo two SETs at 40% and 60% of their predicted maximal workload. A second group of thirty-one healthy volunteers were recruited to undergo three SETs of differing modalities; Cycle ergometry, Step and Shuttle Walk tests. HRR was quantified using the conventional indices HRR1 and HRR2 (calculated as heart rate (HR) on exercise cessation minus HR at 1 and 2 min of rest) and a novel area under the HRR vs. time curve (HRRAUC) method. Reproducibility of results was assessed using intra-class correlation coefficient (ICC) and limits of agreements. Results: The results showed that HRR1 and HRR2 were poorly reproducible across differing workloads and exercise modalities (ICC < 0.45 for all comparisons) whereas HRRAUC proved to be at least moderately reproducible (ICC > 0.52 for all comparisons). Conclusions: These results suggest that HRRAUC may be a superior way of quantifying HRR following SETs, adding objectivity to SET results. Quantifying HRRAUC could prove to have useful clinical applications for pre-operative risk assessment, assessing fitness to undergo treatment and monitoring disease progression. [ABSTRACT FROM AUTHOR]

Background: Large scale population norms for peak oxygen uptake (VO2peak) during cycle ergometry (CE) have been published for men and women across a wide range of ages. Although upper body functional capacity has an important role in activities of daily living far less is known regarding the effect of age and sex on upper body functional capacity (i.e. arm crank ergometry; ACE). The aim of this review was to determine the effect of age and sex on VO2peak obtained during ACE and CE in the same participants. Method: The review was pre-registered with PROSEPERO (Ref: CRD42022349566). A database search using Academic Search Complete including CINAHL complete, CINHAL Ultimate, Medline, PubMed, SPORTDiscus was undertaken. Results: The initial search yielded 460 articles which was reduced to 243 articles following removal of duplicates. Twenty-five articles were subsequently excluded based on title resulting in 218 articles considered for retrieval. Following review of the abstracts, 78 further articles were excluded leaving 140 to be assessed for eligibility. Eighty-five articles were subsequently excluded, resulting in 55 articles being included. The decrease in VO2peak with age during CE was consistent with previous studies. Decreases in VO2peak during ACE with age, although paralleling those of CE, appeared to be of greater functional importance. When changes in VO2peak were considered below the age of 50 years little change was observed for absolute VO2peak during ACE and CE. In contrast, relative VO2peak demonstrated decreases in VO2peak for both ACE and CE likely reflecting increases in body mass and body fat percentage with age. After 50 years of age absolute and relative VO2peak demonstrated more similar and subtle responses. Heterogeneity across studies for both absolute and relative VO2peak between ACE and CE was large. Although strict inclusion criteria were applied, the inter-individual variation in sample populations was likely the main source of heterogeneity. There was a considerable lack data sets available for ages above 40 years of age. Conclusions: These responses suggest that upper body VO2peak decreases in line with that of the lower body but, due to the lower peak values achieved during ACE, decreases in VO2peak may have more profound functional impact compared to that for the lower body. Using absolute and relative measures of VO2peak results in different age-related profiles when considered below 50 years of age. To further our understanding of whole body ageing more data is required for participants in mid and later life. The association between VO2peak and underlying physiological factors with age needs to be studied further, particularly in conjunction with activities of daily living and independent living.

Abstract Purpose Submaximal exercise tests (SET) are an easier to conduct and less physically demanding alternative to cardiopulmonary exercise testing for assessment of pre-operative fitness. Assessment of heart rate recovery (HRR) following SETs offers an easily obtained marker of vagal reactivation and sympathetic withdrawal and therefore provides an indication of an individual’s fitness. This study sought to assess the reproducibility of HRR across different workloads and modalities of SET. Methods Thirty-four healthy volunteers were recruited to undergo two SETs at 40% and 60% of their predicted maximal workload. A second group of thirty-one healthy volunteers were recruited to undergo three SETs of differing modalities; Cycle ergometry, Step and Shuttle Walk tests. HRR was quantified using the conventional indices HRR1 and HRR2 (calculated as heart rate (HR) on exercise cessation minus HR at 1 and 2 min of rest) and a novel area under the HRR vs. time curve (HRRAUC) method. Reproducibility of results was assessed using intra-class correlation coefficient (ICC) and limits of agreements. Results The results showed that HRR1 and HRR2 were poorly reproducible across differing workloads and exercise modalities (ICC 0.52 for all comparisons). Conclusions These results suggest that HRRAUC may be a superior way of quantifying HRR following SETs, adding objectivity to SET results. Quantifying HRRAUC could prove to have useful clinical applications for pre-operative risk assessment, assessing fitness to undergo treatment and monitoring disease progression.

The aim of this study is to scientifically substantiate the possibilities of complex use of cycle- and power-ergometry in determining aerobic and anaerobic-aerobic performance of power nature. Materials and methods. Young athletes (boys) aged 15–16 (n = 91) of the Brovary Higher School of Physical Education (Kyiv region) (experimental group), who participated in the study, were divided into two groups. Group А (n = 47) – speed-power sports (boxing, freestyle wrestling); group B (n = 44) – endurance sports (track and field athletics: 800, 1500, 3000 and 5000-meters race, bicycle racing 50 and 75 km). Sports experience was 3–5 years and more. The control group (group К) consisted of students aged 15–16, who did not play sports (n = 25). Physical working capacity was determined using two methods: submaximal cycle ergometric test PWC170 and submaximal power ergometric test PWC170. Method of power ergometry (patent of Ukraine No 49417) has no analogues in countries of near and far abroad. Results. The fact of the specific influence of different kinds of dosed physical exercises (strength and power exercises) on PWC170 indicators was established. Thus, no probable differences in aerobic performance indicators were found in wrestlers and boxers during the cycle ergometric test. And conversely, under the conditions of power ergometric testing, we find a significant increase in their PWC170 indicators in relation to athletes of endurance sports. The opposite character of changes was observed when testing the track and field athletes and bike riders. According to the results of the conducted cycle ergometry, these athletes had a significant increase in aerobic performance indicators in comparison with the athletes of speed-power sports. However, the changes of anaerobic-aerobic performance were not significant. It was observed that the adolescents, who did not play sports, had statistically insignificant changes in PWC170 indicators both in the conditions of cycle ergometric and power ergometric testing. Conclusions. The fact of specific influence of different types of training exercises on the body functions of adolescents was confirmed. The possibility of introducing the methods of complex use of aerobic (cycle ergometry) and anaerobic-aerobic loads (power-ergometry) into the practice of medico-biological control of young athletes is shown. Diagnostics of various types of physical working capacity (PWC170) will provide the coach with operational information about the functional state of the athletes’ body, which will allow to effectively manage a training process.

This meta-analysis summarizes experiments that have assessed quadriceps pain intensity (PI) during cycling in healthy individuals. Secondly, it tested the impact of eleven plausible moderators of that pain: data source, pain measure, participant sex and fitness, study purpose and comparison condition, analgesic intervention, and exercise task, duration, number of bouts, and intensity. Articles published before September 15, 2022 were found by searching PubMed, Web of Science, PsychInfo, SportDiscus, Science Direct, and Google Scholar. Inclusion criteria were (i) a randomized between-subjects design or a within-subjects crossover design, (ii) healthy participants without preexisting pain conditions, (iii) leg cycling on a stationary ergometer, and (iv) quadriceps PI measured during cycling. Study quality was assessed, Hedge's d effect sizes were computed, and a mixed effects model was used to generate a mean effect size (Δ). Moderators were chosen a priori to account for heterogeneity. A total of 95 effects were derived from 35 studies. A mixed effects model indicated the mean effect size (Δ) was 0.671 (95% CI = 0.442 to 0.899, z = 5.754, P < 0.001). Total heterogeneity was high in this model (τ2 = 0.942, I2 = 80.90%, H2 = 5.24). [ABSTRACT FROM AUTHOR]

Background: Interpretation of cardiopulmonary exercise testing (CPET) results requires thorough understanding of test confounders such as anthropometrics, comorbidities and medication. Here, we comprehensively assessed the clinical determinants of cardiorespiratory fitness and its components in a heterogeneous patient sample. Methods: We retrospectively collected medical and CPET data from 2320 patients (48.2% females) referred for cycle ergometry at the University Hospital Leuven, Belgium. We assessed clinical determinants of peak CPET indexes of cardiorespiratory fitness (CRF) and its hemodynamic and ventilatory components using stepwise regression and quantified multivariable‐adjusted differences in indexes between cases and references. Results: Lower peak load and peak O2 uptake were related to: higher age, female sex, lower body height and weight, and higher heart rate; to the intake of beta blockers, analgesics, thyroid hormone replacement and benzodiazepines; and to diabetes mellitus, chronic kidney disease, non‐ST elevation myocardial infarction and atrial fibrillation (p < 0.05 for all). Lower peak load also correlated with obstructive pulmonary diseases. Stepwise regression revealed associations of hemodynamic and ventilatory indexes (including heart rate, O2 pulse, systolic blood pressure and ventilation at peak exercise and ventilatory efficiency) with age, sex, body composition and aforementioned diseases and medications. Multivariable‐adjusted differences in CPET metrics between cases and controls confirmed the associations observed. Conclusion: We described known and novel associations of CRF components with demographics, anthropometrics, cardiometabolic and pulmonary diseases and medication intake in a large patient sample. The clinical implications of long‐term noncardiovascular drug intake for CPET results require further investigation. [ABSTRACT FROM AUTHOR]

Purpose: This study examined the physiological, perceptual, and performance effects of a 6% carbohydrate (CHO) drink during variable-intensity exercise (VIE) and a postexercise test in premenarchal girls. Methods: A total of 10 girls (10.4 [0.7] y) participated in the study. VO2peak was assessed, and the girls were familiarized with VIE and performance during the first visit. The trial order (CHO and placebo) was randomly assigned for subsequent visits. The drinks were given before VIE bouts and 1-minute performance (9 mL/kg total). Two 15-minute bouts of VIE were completed (10 repeated sequences of 20%, 55%, and 95% power at VO2peak and maximal sprints) before a 1-minute performance sprint. Results: The mean power, peak power, heart rate (HR), %HRpeak, and rating of perceived exertion during VIE did not differ between trials. However, the peak power decreased, and the rating of perceived exertion increased from the first to the second bout. During the 1-minute performance, there were no differences between the trial (CHO vs placebo) for HR (190 [9] vs 189 [9] bpm), %HRpeak (97.0% [3.2%] vs 96.6% [3.0%]), rating of perceived exertion (7.8 [2.3] vs 8.1 [1.9]), peak power (238 [70] vs 235 [60] W), fatigue index (54.7% [10.0%] vs 55.9% [12.8%]), or total work (9.4 [2.6] vs 9.4 [2.1] kJ). Conclusion: CHO supplementation did not alter physiological, perceptual, or performance responses during 30 minutes of VIE or postexercise sprint performance in premenarchal girls. [ABSTRACT FROM AUTHOR]

Assessment of exercise tolerance is one of the methods for clinical diagnosis of health status, which makes it possible to determine and comprehensively analyze the degree of physical fitness of a patient, his ability to tolerate physical exertion, and the adaptation capabilities of the body. The level of exercise tolerance plays a major role in assessing health status and quality of life of children and adolescents, as it depends on a whole set of factors, namely: the functional properties of the cardiovascular, respiratory, and musculoskeletal systems and the level of physical fitness. Tests with dosed physical activity are used to assess exercise tolerance. The diagnostic value of methods for evaluating exercise tolerance consists in the possibility of constant monitoring of heart rate, blood pressure, recording of an electrocardiogram, fixation of the level of blood oxygen saturation, determination of peak or maximum oxygen consumption obtained by direct and indirect methods during the test. The interpretation of the obtained results creates significant opportunities in terms of the diagnostic search for a pediatrician. The purpose of the work is to summarize the literature data about peculiarities of the tests with dosed physical activity, their diagnostic value, and global recommendations for assessing exercise tole­rance in children, to evaluate the results of own research.

Introduction. The study aimed to evaluate haemodynamic changes in peripheral blood flow, vascular conductance (VC), and peripheral vascular resistance (PVR) in healthy individuals undergoing passive and active lower limb cycle ergometry. Methods. This was a prospective, controlled, randomized study with a crossover design, in which 14 normotensive volunteers were allocated to receive: (1) assessment without intervention (control group); (2) passive lower limb cycle ergometry; and (3) active cycle ergometry of lower limbs. In the physical exercise session of the active and passive lower limb cycle ergometry protocol, the volunteers were placed in the supine position and then performed aerobic exercise for 20 minutes. Forearm blood flow was measured with a venous occlusion plethysmograph, blood pressure was evaluated with oscillometric and automatic equipment, and heart rate was monitored continuously through lead II of electrocardiogram. Results. Active cycle ergometry was able to promote hypotension after physical exercise owing to a reduction in mean blood pressure (p = 0.000), with an improvement in vascular function as reflected by a reduction in PVR (p = 0.000) and an increase in VC (p = 0.000). Although the reduction in mean blood pressure in the passive cycle ergometry group was not significant, it was sufficient to promote an increase in VC (p = 0.049) and a reduction in PVR (p = 0.008). Conclusions. A single session of 20 minutes of physical exercise with passive or active cycle ergometry of the lower limbs was sufficient to promote haemodynamic changes in normotensive individuals. [ABSTRACT FROM AUTHOR]

Cardiopulmonary exercise testing (CPET) modalities, treadmill (TM), and cycle ergometer (CE), influence maximal gas exchange and heart rate (HR) responses. Little is known regarding CPET modality effect on submaximal biomarkers during childhood and adolescence. Ninety-four healthy participants (7-34 y.o., 53% female) performed TM and CE CPET to address two major gaps: (1) the effect of modality on submaximal CPET biomarkers, and (2) estimation of work rate in TM CPET. Breath-by-breath gas exchange enabled calculation of linear regression slopes such as V˙ O2 /ΔHR and Δ V˙ E/Δ V˙ CO2 . Lean body mass (LBM) was measured with dual X-ray absorptiometry. We tested a novel TM CPET estimate of work rate based on TM velocity2 , incline, and body mass (VIM). Like the linear relationship between V˙ O2 and work rate in CE CPET, V˙ O2 increased linearly with TM VIM. TM Δ V˙ O2 /ΔHR was highly correlated with CE (r = 0.92), and each increased substantially with LBM (P

The aim of this study was to develop distributions of VO2max based on measured values that exist in the literature in prepubertal boys using cycle ergometry. PRISMA guidelines were followed in conducting this research. One database was searched for peak and maximal VO2 values in healthy boys with mean age under 11 years old. Data were split into articles reporting absolute and relative VO2max values and analyzed accordingly. Multilevel models grounded in Bayesian principles were used. We investigated associations between VO2max and body mass, year of the study, and country of origin. Differences in "peak" and "maximal" VO2 were assessed. Absolute VO2max (Lmin−1) increases with age (P ~100%) but mean relative VO2max does not change (P ~100%). Absolute VO2max is higher in more recent studies (P = 95.7 ± 0.3%) and mean relative VO2max is lower (P = 99.6 ± 0.1%). Relative VO2max in the USA is lower compared with boys from other countries (P = 98.8 ± 0.2%), but there are no differences in absolute values. Mean aerobic capacity estimates presented as "peak" values are higher than "maximal" values on an absolute basis (P = 97.5 ± 0.3%) but not on a relative basis (P = 99.6 ± 0.1%). Heavier boys have lower cardiorespiratory fitness (P ≈ 100%), and body mass seems to be increasing faster with age in the USA compared with other countries (P = 92.3 ± 0.3%). New reference values for cardiorespiratory fitness are presented for prepubertal boys obtained with cycle ergometry. This is new, as no reference values have been determined so far based on actual measured values in prepubertal boys. Aerobic capacity normalized to body weight does not change with age. Cardiorespiratory fitness in prepubertal boys is declining, which is associated with increasing body mass over the last few decades. Lastly, this study did not find any statistically significant difference in the sample's mean aerobic capacity estimates using the "peak" and "maximum" distinctions identified in the literature. [ABSTRACT FROM AUTHOR]

New Findings: What is the central question of this study?Is the stabilising function of the diaphragm altered differentially in response to involuntary augmented breaths induced with or without lower‐limb movements?What is the main finding and its importance?At equivalent levels of ventilation, the diaphragm generated higher passive pressure but moved significantly less during incremental cycle ergometry compared with progressive hypercapnia. Diaphragm excursion velocity and power output did not differ between the two tasks. These findings imply that the power output of the diaphragm during stabilising tasks involving the lower limbs may be preserved via coordinated changes in contractile shortening. Activity of key respiratory muscles, such as the diaphragm, must balance the demands of ventilation with the maintenance of stable posture. Our aim was to test whether the stabilising function of the diaphragm would be altered differentially in response to involuntary augmented breaths induced with or without lower‐limb movements. Ten healthy volunteers (age 21 (2) years; mean (SD)) performed progressive CO2‐rebreathe (5% CO2, 95% O2) followed 20 min later by incremental cycle exercise (15–30 W/min), both in a semi‐recumbent position. Ventilatory indices, intrathoracic pressures and ultrasonographic measures of diaphragm shortening were assessed before, during and after each task. From rest to iso‐time, inspiratory tidal volume and minute ventilation increased two‐ to threefold. At equivalent levels of tidal volume and minute ventilation, mean inspiratory transdiaphragmatic pressure (P¯di${\bar P_{{\rm{di}}}}$) was consistently higher during exercise compared with CO2‐rebreathe due to larger increases in gastric pressure and the passive component of P¯di${\bar P_{{\rm{di}}}}$ (i.e., mechanical output due to static contractions), and yet diaphragm excursion was consistently lower. This lower excursion during exercise was accompanied by a reduction in excursion time with no difference in the active component of P¯di${\bar P_{{\rm{di}}}}$. Consequently, the rates of increase in excursion velocity (excursion/time) and power output (active P¯di${\bar P_{{\rm{di}}}}$ × velocity) did not differ between the two tasks. In conclusion, the power output of the human diaphragm during dynamic lower‐limb exercise appears to be preserved via coordinated changes in contractile shortening. The findings may have significance in settings where the ventilatory and stabilising functions of the diaphragm must be balanced (e.g., rehabilitation). [ABSTRACT FROM AUTHOR]

Peak ratios of pulmonary gas-exchange to ventilation during exercise (V˙O2/V˙E and V˙CO2/V˙E, termed "circulatory equivalents") are sensitive to heart failure (HF) severity, likely reflecting low and/or poorly distributed pulmonary perfusion. We tested whether peak V˙O2/V˙E and V˙CO2/V˙E would: (1) distinguish HF patients from controls; (2) be independent of incremental exercise protocol; and (3) correlate with lactate threshold (LT) and ventilatory compensation point (VCP), respectively. Twenty-four HF patients (61±11 years) with reduced ejection fraction (31±8%) and 11 controls (63±7 years) performed ramp-incremental cycle ergometry. Eighteen HF patients also performed slow (5±1 W/min), medium (9±4 W/min), and fast (19±6 W/min) ramps. Peak V˙O2/V˙E and V˙CO2/V˙E from X-Y plot, and LT and VCP from 9-panel plot, were determined by 2 independent, blinded, assessors. Peak V˙O2/V˙E (31.2±4.4 versus 41.8±4.8 mL/L; P

To analyze the feasibility of and pain-related tolerance to a maximal cardiopulmonary exercise test (CPET), and the relationship between the aerobic capacity and central sensitization (CS) in patients with chronic low back pain (CLBP). An observational study, combining a cross-sectional and a prospective 24-hour follow-up was performed. Participants underwent a maximal CPET on a cycle ergometer and were assessed with three measures of CS (CS Inventory, quantitative sensory testing and heart rate variability). Before the CPET, immediately afterwards and 24 h after, the Pain Response Questionnaire (PRQ) was filled out. The CPET was considered feasible when >80% performed maximally, and tolerable when <20% reported relevant pain increase, body reactions and additional pain medication use in the PRQ. Multiple regression analyses were applied to assess the relationship between the aerobic capacity (VO2max) and CS measures, corrected for confounders. 74 patients with CLBP participated of which 30 were male, mean age was 40.4 years (SD: 12.4) and median VO2max was 23.9 ml/kg/min (IQR: 18.2–29.4). CPET was completed by 92%. No serious adverse events occurred. A relevant pain increase was reported in the upper legs by 40% immediately after CPET and by 28% 24 h afterwards, 27% reported body reactions after 24 h, and 22% increased pain medication use 24 h after CPET. Very weak and not significant relations (rpartial=−0.21 to 0.05; p > 0.10) were observed between aerobic capacity and CS measures. A maximal CPET is feasible in patients with CLBP. Most, but not all, tolerated it well. CS was not related to aerobic capacity. Maximal CPET is feasible in patients with CLBP and well tolerated by most patients. Maximal CPET can be safely applied to assess the aerobic capacity of patients with CLBP. Aerobic capacity is unrelated to central sensitization. Outcomes of a maximal CPET and the pain response to straining activity can be used to provide valid information for the decision-making of exercise therapy. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to evaluate the effect of early bedside arm and leg cycle ergometer exercises as compared to routine physiotherapy on sitting and standing ability in hospitalized acute stroke patients.Materials and Methods: Thirty-four consecutive patients with acute stroke were included in the randomized controlled trial. Patients were divided into two groups based on 1:1 simple randomization Experimental group (n = 18) and control group (n = 16). Experimental Group received arm and leg cycle ergometry along with conventional physiotherapy exercises, while the patients in the control group received conventional physiotherapy exercises. Both the groups received treatment for a total duration of 50 min session, twice a day for 7 days. Preintervention and postintervention measurements were taken for both groups using performance-oriented mobility assessment, postural assessment scale for stroke, Motricity Index, and Trunk control scale.Results: Statistically significant improvement (P < 0.05) was observed in the experimental group and control groupafter intervention among all the outcome measures.Conclusions: Early bedside intervention of cycle ergometer along with routine physiotherapy is effective in improving the sitting and standing abilities, trunk control, and motor function in acute stroke survivors. [ABSTRACT FROM AUTHOR]

Background and Aims: Muscle wasting results in weakness for patients with critical illness. We aim to explore ultrasound-derived rates of change in skeletal muscle in the intensive care unit (ICU) and following discharge to the post-ICU ward., Design: Post hoc analysis of a multicentre randomised controlled trial of functional-electrical stimulated cycling, recumbent cycling, and usual care delivered in intensive care., Method: Participants underwent ultrasound assessment of rectus femoris at ICU admission, weekly in the ICU, upon awakening, ICU discharge, and hospital discharge. The primary outcome was rate of change in rectus femoris cross-sectional area (ΔRF CSA ) in mm 2 /day in the ICU (enrolment to ICU discharge) and in the post-ICU ward (ICU discharge to hospital discharge). Secondary outcomes included rate of change in echo intensity (ΔEI), standard deviation of echo intensity (ΔEI SD ), and the intervention effect on ultrasound measures. Echo intensity is a quantitative assessment of muscle quality. Elevated echo intensity may indicate fluid infiltration, adipose tissue, and reduced muscle quality., Results: 154 participants were included (mean age: 58 ± 15 years, 34% female). Rectus femoris cross-sectional area declined in the ICU (-4 mm 2 /day [95% confidence interval {CI}: -9 to 1]) and declined further in the ward (-9 mm 2 /day [95% CI: -14 to -3]) with a mean difference between ICU and ward of -5 mm 2 /day ([95% CI: -2, to 11]; p = 0.1396). There was a nonsignificant difference in ΔEI between in-ICU and the post-ICU ward of 1.2 ([95% CI: -0.1 to 2.6]; p = 0.0755), a statistically significant difference in ΔEI SD between in-ICU and in the post-ICU ward of 1.0 ([95% CI, 0.5 to 1.5]; p = 0.0003), and no difference in rate of change in rectus femoris cross-sectional area between groups in intensive care (p = 0.411) or at hospital discharge (p = 0.1309)., Conclusions: Muscle wasting occurs in critical illness throughout the hospital admission. The average rate of loss in muscle cross-sectional area does not slow after ICU discharge, even with active rehabilitation., Competing Interests: Conflict of interest The authors declare no potential conflicts of interest with respect to the research, authorship and/or publication of this article., (Copyright © 2024 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.)

Background: Intensive care unit (ICU) survivors face functional limitations due to ICU-acquired weakness. Arm cycle ergometry (ACE) introduced in the ICU may improve physical function. To our knowledge, there is limited evidence on the effectiveness of ACE and physical function outcomes in critically ill patients., Objective: The objective of this systematic review was to examine the impact of ICU-based ACE on physical function, safety, and other clinical outcomes., Review Method Used: Systematic Review., Data Sources: A search of seven databases was conducted from the inception to January 1, 2023: Medline Ahead of Print, Ovid MEDLINE(R), Allied and Complementary Medicine Database (AMED), Embase, Cochrane Central, Physiotherapy Evidence Database, and Cumulative Index to Nursing and Allied Health Literature (CINAHL)., Review Methods: We included two arm studies of critically ill adults admitted to the ICU who received ACE and any comparator for our primary outcome, physical function. Our secondary outcomes included severe events. We included safety studies with or without a comparator group. Screening, data abstraction, and risk-of-bias assessments were completed independently, in duplicate. We used the Grading of Recommendations, Assessment, Development, and Evaluation approach to assess the overall certainty of evidence., Results: We screened 651 citations and included eight studies that enrolled 183 patients. Due to heterogeneity, meta-analysis was not performed. For our primary outcome, one randomised controlled trial found significant improvements in physical function, measured by the Barthel Index with ACE, whereas a nonrandomised study showed no difference. Out of the six studies reporting safety, none reported any severe safety events. The overall certainty of evidence was very low., Conclusion: ACE initiated in the ICU is a likely safe intervention. Based on the limited ACE studies and heterogeneity between studies, further research with more rigorous studies evaluating important outcomes for patients is needed., (Copyright © 2024 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.)

Background: Survivors of critical illness are at risk of developing physical dysfunction following intensive care unit (ICU) discharge. ICU-based rehabilitation interventions, such as early in-bed cycle ergometry, may improve patients' short-term physical function., Objective: Before unblinding and trial database lock, we describe a prespecified statistical analysis plan (SAP) for the CYCLE (Critical Care Cycling to Improve Lower Extremity Strength) randomized controlled trial (RCT)., Methods: CYCLE is a 360-patient, international, multicenter, open-label, parallel-group RCT (1:1 ratio) with blinded primary outcome assessment at 3 days post-ICU discharge. The principal investigator and statisticians of CYCLE prepared this SAP with approval from the steering committee and coinvestigators. The SAP defines the primary and secondary outcomes (including adverse events) and describes the planned primary, secondary, and subgroup analyses. The primary outcome of the CYCLE trial is the Physical Function Intensive Care Unit Test-scored (PFIT-s) at 3 days post-ICU discharge. The PFIT-s is a reliable and valid performance-based measure. We plan to use a frequentist statistical framework for all analyses. We will conduct a linear regression to evaluate the primary outcome, incorporating randomization as an independent variable and adjusting for age (≥65 years versus <65 years) and center. The regression results will be reported as mean differences in PFIT-s scores with corresponding 95% CIs and P values. We consider a 1-point difference in PFIT-s score to be clinically important. Additionally, we plan to conduct 3 subgroup analyses: age (≥65 years versus <65 years), frailty (Baseline Clinical Frailty Scale ≥5 versus <5), and sex (male versus female)., Results: CYCLE was funded in 2017, and enrollment was completed in May 2023. Data analyses are complete, and the first results were submitted for publication in 2024., Conclusions: We developed and present an SAP for the CYCLE RCT and will adhere to it for all analyses. This study will add to the growing body of evidence evaluating the efficacy and safety of ICU-based rehabilitation interventions., Trial Registration: ClinicalTrials.gov NCT03471247; https://clinicaltrials.gov/ct2/show/NCT03471247 and NCT02377830; https://clinicaltrials.gov/ct2/show/NCT02377830., International Registered Report Identifier (irrid): RR1-10.2196/54451., (©Diane Heels-Ansdell, Laurel Kelly, Heather K O'Grady, Christopher Farley, Julie C Reid, Sue Berney, Amy M Pastva, Karen EA Burns, Frédérick D'Aragon, Margaret S Herridge, Andrew Seely, Jill Rudkowski, Bram Rochwerg, Alison Fox-Robichaud, Ian Ball, Francois Lamontagne, Erick H Duan, Jennifer Tsang, Patrick M Archambault, Avelino C Verceles, John Muscedere, Sangeeta Mehta, Shane W English, Tim Karachi, Karim Serri, Brenda Reeve, Lehana Thabane, Deborah Cook, Michelle E Kho. Originally published in JMIR Research Protocols (https://www.researchprotocols.org), 28.10.2024.)

PurposeWe aimed to identify a blood flow restriction (BFR) endurance exercise protocol that would both maximize cardiopulmonary and metabolic strain, and minimize the perception of effort.MethodsTwelve healthy males (23 ± 2 years, 75 ± 7 kg) performed five different exercise protocols in randomized order: HI, high-intensity exercise starting at 105% of the incremental peak power (P peak); I-BFR30, intermittent BFR at 30% P peak; C-BFR30, continuous BFR at 30% P peak; CON30, control exercise without BFR at 30% P peak; I-BFR0, intermittent BFR during unloaded exercise. Cardiopulmonary, gastrocnemius oxygenation (StO2), capillary lactate ([La]), and perceived exertion (RPE) were measured.ResultsV̇O2, ventilation (V̇ E), heart rate (HR), [La] and RPE were greater in HI than all other protocols. However, muscle StO2 was not different between HI (set1-57.8 ± 5.8; set2-58.1 ± 7.2%) and I-BRF30 (set1-59.4 ± 4.1; set2-60.5 ± 6.6%, p

Purpose: The aim of the study was to determine the effect of supramaximal exercise intensity during constant work-rate cycling to exhaustion on the accumulated oxygen deficit (AOD) and to determine the test--retest reliability of AOD. Methods: Twenty-one trained male cyclists and triathletes (mean ± SD for age and maximal oxygen uptake [...O2max] were 41 ± 7 y and 4.53 ± 0.54 L/min, respectively) performed initial tests to determine the linear relationship between ...O2 and power output, and ...O2max. In subsequent trials, AOD was determined from exhaustive square-wave cycling trials at 105%, 112.5% (in duplicate), 120%, and 127.5% ...O2max. Results: Exercise intensity had an effect (P = .011) on the AOD (3.84 ± 1.11, 4.23 ± 0.96, 4.09 ± 0.87, and 3.93 ± 0.89 L at 105%, 112.5%, 120%, and 127.5% ...O2max, respectively). Specifically, AOD at 112.5% ...O2max was greater than at 105% ...O2max (P = .033) and at 127.5% ...O2max (P = .022), but there were no differences between the AOD at 112.5% and 120% ...O2max. In 76% of the participants, the maximal AOD occurred at 112.5% or 120% ...O2max. The reliability statistics of the AOD at 112.5% ...O2max, determined as intraclass correlation coefficient and coefficient of variation, were .927 and 8.72%, respectively. Conclusions: The AOD, determined from square-wave cycling bouts to exhaustion, peaks at intensities of 112.5-120% ...O2max. Moreover, the AOD at 112.5% ...O2max exhibits an 8.72% test--retest reliability. [ABSTRACT FROM AUTHOR]

Objective: Aerobic capacity (AC) is inversely associated with a high risk of cardiovascular morbidity and mortality as well as all-cause mortality. Cardiopulmonary exercise testing (CPET) represents the gold standard for assessing exercise capacity based on maximum oxygen uptake (VO2max). The purpose of our study was to provide for the first time CPET-derived normative reference values in a Greek cohort of apparently healthy men and women on a cycle ergometer to evaluate their AC, and to compare our results with similar studies from other countries. Methods: A cohort of 194 apparently healthy subjects (118 males and 76 females, age range, 15-69 years) was submitted to CPET using a cycle ergometer. Mean ± SD values for several exercise parameters, VO2max included, were determined. We compared our results with existing data derived from USA and North Europe cohorts. Results: Male subjects achieved significantly higher levels of relative and absolute VO2max (p

Purpose: This study aimed to establish a new threshold parameter called the physical working capacity at pain intensity threshold (PWCPIT) using a pain intensity scale and mathematical methods similar to those used to develop the physical working capacity at oxygen consumption threshold (PWCVO2) and physical working capacity at heart rate threshold (PWCHRT). The study had two objectives: (i) to examine the relationship between PWCPIT and traditional PWC measures and (ii) to explore the physiological mechanisms underlying the relationship between pain perception and capacity thresholds.Fourteen male volunteers (age 21 ± 2 years, height 176 ± 6 cm, weight 76 ± 9 kg, VO2peak 37.8 ± 7.8 ml/kg/min−1) underwent an incremental exhaustion test and four 8-min randomly ordered work bouts on different days at 70–100% peak power output (119–320 W) to establish their PWCPIT, PWCHRT and PWCVO2. One-way repeated-measures ANOVA with Bonferroni post hoc tests and a zero-order correlation matrix were used to analyze these thresholds.PWCPIT significantly correlated with PWCHRT (r = 0.88, P < 0.001), PWCVO2 (r = 0.84, P < 0.001), and gas exchange threshold (GET) (r = 0.7, P = 0.006).The model for estimating PWCHRT and PWCVO2 can be applied to determine the PWCPIT. By examining how PWCPIT aligns with, differs from, or complements existing PWC threshold measures, researchers may provide a more comprehensive understanding of the factors that govern endurance performance.Methods: This study aimed to establish a new threshold parameter called the physical working capacity at pain intensity threshold (PWCPIT) using a pain intensity scale and mathematical methods similar to those used to develop the physical working capacity at oxygen consumption threshold (PWCVO2) and physical working capacity at heart rate threshold (PWCHRT). The study had two objectives: (i) to examine the relationship between PWCPIT and traditional PWC measures and (ii) to explore the physiological mechanisms underlying the relationship between pain perception and capacity thresholds.Fourteen male volunteers (age 21 ± 2 years, height 176 ± 6 cm, weight 76 ± 9 kg, VO2peak 37.8 ± 7.8 ml/kg/min−1) underwent an incremental exhaustion test and four 8-min randomly ordered work bouts on different days at 70–100% peak power output (119–320 W) to establish their PWCPIT, PWCHRT and PWCVO2. One-way repeated-measures ANOVA with Bonferroni post hoc tests and a zero-order correlation matrix were used to analyze these thresholds.PWCPIT significantly correlated with PWCHRT (r = 0.88, P < 0.001), PWCVO2 (r = 0.84, P < 0.001), and gas exchange threshold (GET) (r = 0.7, P = 0.006).The model for estimating PWCHRT and PWCVO2 can be applied to determine the PWCPIT. By examining how PWCPIT aligns with, differs from, or complements existing PWC threshold measures, researchers may provide a more comprehensive understanding of the factors that govern endurance performance.Results: This study aimed to establish a new threshold parameter called the physical working capacity at pain intensity threshold (PWCPIT) using a pain intensity scale and mathematical methods similar to those used to develop the physical working capacity at oxygen consumption threshold (PWCVO2) and physical working capacity at heart rate threshold (PWCHRT). The study had two objectives: (i) to examine the relationship between PWCPIT and traditional PWC measures and (ii) to explore the physiological mechanisms underlying the relationship between pain perception and capacity thresholds.Fourteen male volunteers (age 21 ± 2 years, height 176 ± 6 cm, weight 76 ± 9 kg, VO2peak 37.8 ± 7.8 ml/kg/min−1) underwent an incremental exhaustion test and four 8-min randomly ordered work bouts on different days at 70–100% peak power output (119–320 W) to establish their PWCPIT, PWCHRT and PWCVO2. One-way repeated-measures ANOVA with Bonferroni post hoc tests and a zero-order correlation matrix were used to analyze these thresholds.PWCPIT significantly correlated with PWCHRT (r = 0.88, P < 0.001), PWCVO2 (r = 0.84, P < 0.001), and gas exchange threshold (GET) (r = 0.7, P = 0.006).The model for estimating PWCHRT and PWCVO2 can be applied to determine the PWCPIT. By examining how PWCPIT aligns with, differs from, or complements existing PWC threshold measures, researchers may provide a more comprehensive understanding of the factors that govern endurance performance.Conclusion: This study aimed to establish a new threshold parameter called the physical working capacity at pain intensity threshold (PWCPIT) using a pain intensity scale and mathematical methods similar to those used to develop the physical working capacity at oxygen consumption threshold (PWCVO2) and physical working capacity at heart rate threshold (PWCHRT). The study had two objectives: (i) to examine the relationship between PWCPIT and traditional PWC measures and (ii) to explore the physiological mechanisms underlying the relationship between pain perception and capacity thresholds.Fourteen male volunteers (age 21 ± 2 years, height 176 ± 6 cm, weight 76 ± 9 kg, VO2peak 37.8 ± 7.8 ml/kg/min−1) underwent an incremental exhaustion test and four 8-min randomly ordered work bouts on different days at 70–100% peak power output (119–320 W) to establish their PWCPIT, PWCHRT and PWCVO2. One-way repeated-measures ANOVA with Bonferroni post hoc tests and a zero-order correlation matrix were used to analyze these thresholds.PWCPIT significantly correlated with PWCHRT (r = 0.88, P < 0.001), PWCVO2 (r = 0.84, P < 0.001), and gas exchange threshold (GET) (r = 0.7, P = 0.006).The model for estimating PWCHRT and PWCVO2 can be applied to determine the PWCPIT. By examining how PWCPIT aligns with, differs from, or complements existing PWC threshold measures, researchers may provide a more comprehensive understanding of the factors that govern endurance performance. [ABSTRACT FROM AUTHOR]

Large scale population norms for peak oxygen uptake (VO 2peak) during cycle ergometry (CE) have been published for men and women across a wide range of ages. Although upper body functional capacity has an important role in activities of daily living far less is known regarding the effect of age and sex on upper body functional capacity (i.e. arm crank ergometry; ACE). The aim of this review was to determine the effect of age and sex on VO 2peak obtained during ACE and CE in the same participants. The review was pre-registered with PROSEPERO (Ref: CRD42022349566). A database search using Academic Search Complete including CINAHL complete, CINHAL Ultimate, Medline, PubMed, SPORTDiscus was undertaken. The initial search yielded 460 articles which was reduced to 243 articles following removal of duplicates. Twenty-five articles were subsequently excluded based on title resulting in 218 articles considered for retrieval. Following review of the abstracts, 78 further articles were excluded leaving 140 to be assessed for eligibility. Eighty-five articles were subsequently excluded, resulting in 55 articles being included. The decrease in VO 2peak with age during CE was consistent with previous studies. Decreases in VO 2peak during ACE with age, although paralleling those of CE, appeared to be of greater functional importance. When changes in VO 2peak were considered below the age of 50 years little change was observed for absolute VO 2peak during ACE and CE. In contrast, relative VO 2peak demonstrated decreases in VO 2peak for both ACE and CE likely reflecting increases in body mass and body fat percentage with age. After 50 years of age absolute and relative VO 2peak demonstrated more similar and subtle responses. Heterogeneity across studies for both absolute and relative VO 2peak between ACE and CE was large. Although strict inclusion criteria were applied, the inter-individual variation in sample populations was likely the main source of heterogeneity. There was a considerable lack data sets available for ages above 40 years of age. These responses suggest that upper body VO 2peak decreases in line with that of the lower body but, due to the lower peak values achieved during ACE, decreases in VO 2peak may have more profound functional impact compared to that for the lower body. Using absolute and relative measures of VO 2peak results in different age-related profiles when considered below 50 years of age. To further our understanding of whole body ageing more data is required for participants in mid and later life. The association between VO 2peak and underlying physiological factors with age needs to be studied further, particularly in conjunction with activities of daily living and independent living. • Decreases in peak oxygen uptake with age differed between upper body exercise and lower body exercise. • Decreases in upper body peak oxygen uptake across younger age categories were greater for males. • Decreases in upper and lower body peak oxygen uptake with age were greater for females. • There was a considerable lack of data sets available for ages above 40 years old. • Strategies to improve whole body aerobic capacity should consider middle-age groups. [ABSTRACT FROM AUTHOR]

Background: Cycle ergometry (CE) is a method of exercise used in clinical practice. Limited data demonstrate its effectiveness in critically ill patients. We aimed to evaluate the combination of CE and a high-protein diet in critically ill patients. Methods: This was an open label pilot trial comparing conventional physiotherapy with enteral nutrition (EN) (control, Group 1), CE with EN (Group 2), and CE with protein-enriched EN (Group 3). The primary outcome was length of ventilation (LOV). Secondary outcomes were intensive care unit (ICU) mortality, length of ICU stay (ICU LOS), length of hospital stay (Hospital LOS), and rate of re-intubation. Results: Per protocol, 41 ICU patients were enrolled. Thirteen patients were randomized to Group 1 (control), fourteen patients to Group 2, and fourteen patients to Group 3 (study groups). We found no statistically significant difference in LOV between the study arms (14.2 ± 9.6 days, 15.8 ± 7.1 days, and 14.9 ± 9.4 days, respectively, p = 0.89). Secondary outcomes did not demonstrate any significant differences between arms. Conclusions: In this pilot trial, CE combined with either standard EN or protein-enriched EN was not associated with better clinical outcomes, as compared to conventional physiotherapy with standard EN. Larger trials are needed in order to further evaluate this combination. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop distributions of VO2max based on measured values that exist in the literature in prepubertal boys using cycle ergometry. PRISMA guidelines were followed in conducting this research. One database was searched for peak and maximal VO2 values in healthy boys with mean age under 11 years old. Data were split into articles reporting absolute and relative VO2max values and analyzed accordingly. Multilevel models grounded in Bayesian principles were used. We investigated associations between VO2max and body mass, year of the study, and country of origin. Differences in “peak” and “maximal” VO2 were assessed. Absolute VO2max (Lmin−1) increases with age (P ~100%) but mean relative VO2max does not change (P ~100%). Absolute VO2max is higher in more recent studies (P = 95.7 ± 0.3%) and mean relative VO2max is lower (P = 99.6 ± 0.1%). Relative VO2max in the USA is lower compared with boys from other countries (P = 98.8 ± 0.2%), but there are no differences in absolute values. Mean aerobic capacity estimates presented as “peak” values are higher than “maximal” values on an absolute basis (P = 97.5 ± 0.3%) but not on a relative basis (P = 99.6 ± 0.1%). Heavier boys have lower cardiorespiratory fitness (P ≈ 100%), and body mass seems to be increasing faster with age in the USA compared with other countries (P = 92.3 ± 0.3%). New reference values for cardiorespiratory fitness are presented for prepubertal boys obtained with cycle ergometry. This is new, as no reference values have been determined so far based on actual measured values in prepubertal boys. Aerobic capacity normalized to body weight does not change with age. Cardiorespiratory fitness in prepubertal boys is declining, which is associated with increasing body mass over the last few decades. Lastly, this study did not find any statistically significant difference in the sample’s mean aerobic capacity estimates using the ”peak” and “maximum” distinctions identified in the literature.

One-legged cycling has served as a valuable research tool and as a training and rehabilitation modality. Biomechanics of one-legged cycling are unnatural because the individual must actively lift the leg during flexion, which can be difficult to coordinate and cause premature fatigue. We compared ankle, knee, and hip biomechanics between two-legged, one-legged, and counter-weighted (11.64 kg) one-legged cycling. Ten cyclists performed two-legged (240 W), one-legged (120 W), and counterweighted one-legged (120 W) cycling (80 rpm). Pedal forces and limb kinematics were recorded to determine work during extension and flexion. During counterweighted one-legged cycling relative ankle dorsiflexion, knee flexion, and hip flexion work were less than one-legged but greater than two-legged cycling (all P < .05). Relative ankle plantar flexion and hip extension work for counterweighted one-legged cycling were greater than one-legged but less than two-legged cycling (all P < .05). Relative knee extension work did not differ across conditions. Counterweighted one-legged cycling reduced but did not eliminate differences in joint flexion and extension actions between one- and two-legged cycling. Even with these differences, counterweighted one-legged cycling seemed to have advantages over one-legged cycling. These results, along with previous work highlighting physiological characteristics and training adaptations to counterweighted one-legged cycling, demonstrate that this exercise is a viable alternative to one-legged cycling. [ABSTRACT FROM AUTHOR]

Bogdanis, GC, Mallios, VJ, Katsikas, C, Fouseki, T, Holman, I, Smith, C, and Astorino, TA. Effects of exercise structure and modality on physiological and perceptual responses to exercise. J Strength Cond Res 35(9): 2427-2432, 2021--This study examined the effect of exercise mode and intensity on physiological and perceptual responses to exercise. Twelve active adults (6 men and 6 women, age 5 21.7 6 1.6 years) initially performed incremental testing on the treadmill (TM) and cycle ergometer (CE) to assess maximal oxygen uptake (V̇O2max) and ventilatory threshold (VT). During the next 4 visits in a randomized order, subjects performed 20 minutes of moderate-intensity continuous exercise (MICE) at an intensity 20% below VT on the TM (TMMICE) and cycle ergometer (CEMICE) as well as time-matched high-intensity interval exercise (HIIE; 10 1-minute bouts at workload equal to 20% above VT followed by 1-minute active recovery) on both modes (TMHIIE and CEHIIE). During exercise, gas exchange data, blood lactate concentration, and perceptual responses (rating of perceived exertion, affective valence, and enjoyment) were assessed. Heart rate (p, 0.001) and V̇O2 (p, 0.001) were higher in response to TMHIIE vs. CEHIIE as well as TMMICE vs. CEMICE. Blood lactate concentration was higher (p5 0.003) in response to CEHIIE vs. TMHIIE. The rating of perceived exertion was significantly higher (p, 0.001) in TMMICE compared with CEMICE which showed the most positive affective valence (p 5 0.009). Enjoyment was similar across all bouts (p 5 0.11). Treadmill-based HIIE leads to higher heart rate and V̇O2 vs. CEHIIE, although there was no difference in affective valence or enjoyment. Practitioners aiming to optimize the cardiorespiratory response to moderate or interval exercise in their clientele should recommend TM running rather than cycling. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to explore if the JT/ST algebraic relationship could be helpful for the identification of ischemic changes in the human cardiovascular system. The suggested visualization technique highlights the specifics of complex dynamical processes in the self-organization of the heart system during the load and recovery processes. It is demonstrated that the nonlinear algebraic relationship between the duration of the JT interval and the ST amplitude can be beneficial for a deeper interpretation of dynamical processes in the human cardiovascular system. The JT/ST relationship is used for the identification of the ischemic changes and for the characterization of individual performance of the person during the load and recovery processes. [ABSTRACT FROM AUTHOR]

Previous authors have reported power-pedaling rate relationships for maximal cycling. However, the joint-specific power-pedaling rate relationships that contribute to pedal power have not been reported. We determined absolute and relative contributions of joint-specific powers to pedal power across a range of pedaling rates during maximal cycling. Ten cyclists performed maximal 3 s cycling trials at 60, 90, 120, 150, and 180 rpm. Joint-specific powers were averaged over complete pedal cycles, and extension and flexion actions. Effects of pedaling rate on relative joint-specific power, velocity, and excursion were assessed with regression analyses and repeated-measures ANOVA. Relative ankle plantar flexion power (25 to 8%; P = .01; R2 = .90) decreased with increasing pedaling rate, whereas relative hip extension power (41 to 59%; P < .01; R2 = .92) and knee flexion power (34 to 49%; P < .01; R2 = .94) increased with increasing pedaling rate. Knee extension powers did not differ across pedaling rates. Ankle joint angular excursion decreased with increasing pedaling rate (48 to 20 deg) whereas hip joint excursion increased (42 to 48 deg). These results demonstrate that the often-reported quadratic power-pedaling rate relationship arises from combined effects of dissimilar joint-specific power-pedaling rate relationships. These dissimilar relationships are likely influenced by musculoskeletal constraints (ie, muscle architecture, morphology) and/or motor control strategies. [ABSTRACT FROM AUTHOR]

Background: In a trial of early in-bed cycling in critically ill patients, a video demonstrating use of the cycle in addition to verbal description may improve satisfaction with the informed consent process for all persons involved. Methods: A convenience sample of in-person consent encounters for enrolment in TryCYCLE (NCT01885442), a 33-patient pilot study of in-bed cycling with mechanically ventilated patients in an intensive care unit, were recruited. In this study within a trial, using concealed allocation, we randomized consent encounters to a Video or Standard consent approach. Those in the Video group viewed a 2-minute video of a model using in-bed cycling plus the routine verbal description of the study. The Standard group received the routine verbal description only. Patients and/or substitute decision makers (SDMs) were blinded to the study purpose. After each encounter, patients and/or SDMs and the research coordinator submitted written satisfaction and comfort ratings using 7-point scales (higher scores better). We documented consent outcomes and analyzed between group differences with independent group t-tests. Results: We randomized 14 encounters (6 Video, 8 Standard). Ten completed questionnaires (5 in each group) demonstrated no difference in patient and/or SDM satisfaction or comfort between Video or Standard (mean [standard deviation] Satisfaction: 6.8[0.45] vs. 7.0[0] vs. p=0.37; Comfort: 7.0[0] vs. 7.0[0], p>0.99). The research coordinator evaluated all randomized encounters, with no differences between Video or Standard (Satisfaction: 7.0[0] vs. 6.9[0.35], p=0.41; Comfort: 6.7[0.52] vs. 6.9[0.35], p=0.39). All 14 consent encounters enrolled in TryCYCLE. Conclusions: Patient and/or SDM satisfaction and comfort with consent was very high for both the Video and Standard approaches. Further research, including use of videos to portray different study interventions, is needed, including analysis of patient and/or SDM satisfaction, comfort, comprehension, and consent rates. Registration for host trial: ClinicalTrials.gov, NCT01885442, registered on June 25, 2013

Background: Cycle ergometry (CE) is a method of exercise used in clinical practice. Limited data demonstrate its effectiveness in critically ill patients. We aimed to evaluate the combination of CE and a high-protein diet in critically ill patients. Methods: This was an open label pilot trial comparing conventional physiotherapy with enteral nutrition (EN) (control, Group 1), CE with EN (Group 2), and CE with protein-enriched EN (Group 3). The primary outcome was length of ventilation (LOV). Secondary outcomes were intensive care unit (ICU) mortality, length of ICU stay (ICU LOS), length of hospital stay (Hospital LOS), and rate of re-intubation. Results: Per protocol, 41 ICU patients were enrolled. Thirteen patients were randomized to Group 1 (control), fourteen patients to Group 2, and fourteen patients to Group 3 (study groups). We found no statistically significant difference in LOV between the study arms (14.2 ± 9.6 days, 15.8 ± 7.1 days, and 14.9 ± 9.4 days, respectively, p = 0.89). Secondary outcomes did not demonstrate any significant differences between arms. Conclusions: In this pilot trial, CE combined with either standard EN or protein-enriched EN was not associated with better clinical outcomes, as compared to conventional physiotherapy with standard EN. Larger trials are needed in order to further evaluate this combination.

The purpose of this study was to examine the effects of curcumin in combination with fenugreek soluble fiber (CUR + FEN) or fenugreek soluble fiber alone (FEN) on the neuromuscular fatigue threshold (PWCFT), peak oxygen consumption (V̇o2peak), and time to exhaustion (Tlim) on a graded exercise test (GXT), in untrained subjects. The PWCFT estimates the highest power output that can be maintained without evidence of neuromuscular fatigue. Forty-seven untrained, college-aged subjects were randomly assigned to one of 3 supplementation groups; placebo (PLA, n = 15), CUR + FEN (500 mg·d-1, n = 18), or FEN (300 mg·d-1, n = 14). The subjects completed a maximal GXT on a cycle ergometer to determine the PWCFT, V̇o2peak, and Tlim before (PRE) and after (POST) 28 days of daily supplementation. Surface electromyographic signals were recorded from a bipolar electrode arrangement on the vastus lateralis of the right leg during each test. Separate one-way analysis of covariances were used to determine if there were between-group differences for adjusted POST-PWCFT, POST-V̇o2peak, and POST-Tlim values, covaried for the respective PRE-test scores. The adjusted POST-PWCFT for the CUR + FEN group (mean ± SD: 196 ± 58 W) was greater (p = 0.016) than the PLA group (168 ± 49 W) but the FEN group (185 ± 32 W) was not different from the CUR + FEN or PLA groups (p > 0.05). There were no differences for adjusted POST-V̇o2peak (p = 0.612) or POST-Tlim (p = 0.508) among the groups. These findings suggested curcumin combined with fenugreek soluble fiber might delay neuromuscular fatigue. [ABSTRACT FROM AUTHOR]

Background: Survivors of critical illness may experience physical-function deficits after intensive care unit (ICU) discharge. In-ICU cycle ergometry may facilitate early mobilization and decrease functional impairment.Objective: We conducted a systematic review and meta-analysis to understand the effect of in-ICU leg-cycle ergometry on patient-important and clinically relevant outcomes.Data Sources: We searched eight electronic databases from inception until July 2019.Data Extraction: We included randomized controlled trials (RCTs) and nonrandomized studies of critically ill adults admitted to the ICU for ≥24 hours, comparing cycling interventions to control arms that did not receive cycling. Main outcomes included physical function, mechanical ventilation (MV) duration, length of stay (LOS), quality of life (QoL), mortality, and safety. We conducted independent duplicate-citation screening, data abstraction, and risk-of-bias assessments. We pooled RCTs using a random-effects model and calculated the risk ratio (RR), mean difference (MD), or standardized MD with 95% confidence intervals (CIs). We assessed certainty of outcomes using the Grading of Recommendations Assessment, Development, and Evaluation approach.Results: Of 6,531 citations, we included 12 RCTs and 2 nonrandomized studies (n = 926). Between the cycling and control groups, there were no differences in physical function at hospital discharge (3 RCTs; n = 225; standardized MD, 0.07 [95% CI, -0.38 to 0.53]; very low certainty), MV duration (9 RCTs; n = 676; MD, 0.01 [-1.04 to 1.07] days; moderate certainty), ICU LOS (10 RCTs; n = 511; MD, 0.23 [-1.44 to 1.89] days; moderate certainty), hospital LOS (7 RCTs; n = 393, MD -0.07 [-3.87 to 3.73] days; moderate certainty), QoL at 6 months after hospital discharge (2 RCTs; n = 103; MD, 9.13 [13.80 to 32.05] points higher; very low certainty), or hospital mortality (7 RCTs; n = 710; RR 1.09 [0.82 to 1.46]; moderate-certainty). The adverse event rate in cycling sessions was 0.16% across studies (10 studies; 5 of 3,117 sessions; very low certainty).Conclusions: Cycling initiated in the ICU is probably safe; however, we did not find any differences in physical function, MV duration, LOS, QoL, or mortality compared with those not receiving cycling. Rigorously designed RCTs are needed to improve precision and further investigate the effect of cycling on patient-important outcomes. [ABSTRACT FROM AUTHOR]

Merry KL. Estimation of the Minimal Exercise Intensity Associated with Maximal Oxygen Uptake. JEPonline 2020;23(3):55-62. The purpose of the study was to investigate whether modification of a common approach that is used to determine the minimal exercise intensity at whichVO2 max is elicited (iVO2 max) improves its accuracy, when compared to an iVO2 max value refined to its lowest value, and a value derived using an approach considered to be the most suitable method of determining iO2 max. Eleven male cyclists (age 34 ± 8 yrs, body mass 81.6 ± 10.5 kg, height 1.84 ± 0.06 m; VO2 max 4.44 ± 0.48 L·min-1) performed three maximal incremental tests for the determination of iVO2 max(R). iVO2 max was also determined as: (a) the minimum intensity at which VO2 max was attained (Method 1); the ratio of (VO2 max - VO2 at rest) to (C - VO2 at rest), where C is calculated using the last two stages in the incremental test (Method 2a) and again where C is calculated using all stages in the incremental test (Method 2b). Methods 1, 2a, and 2b produced iVO2 max values that were not significantly different from iVO2 max(R). Method 1 produced an iV? O2 max value thatwas less variable and more similar to iVO2 max(R) (CV =1.5%; ICC = 0.99) than 2a (CV = 3.0%; ICC = 0.97) and 2b (CV = 4.1%; ICC = 0.95). Methods 1, 2a, and 2b may provide good estimates of iVO2 max(R), but Method 1 appears to be the most robust method, and may be optimal for setting interval training intensities. [ABSTRACT FROM AUTHOR]

Merry KL. Validity of Common Approaches to Determining the Exercise Intensity at Maximal Oxygen Uptake. JEPonline 2020;23(2):18-28. This study compared 5 common methods used to determine exercise intensity at V̇ O2 max (iV̇ O2 max) with an iV̇ O2 max value refined to its minimum value (iV̇ O2 max(R)). This study ascertained which method estimated the refined value most accurately for the purpose of setting interval training intensities. Fifteen male cyclists (age 34 ± 8 yrs, body mass 80.9 ± 10.2 kg, height 1.82 ± 0.05 m; V̇ O2 max 4.43 ± 0.49 L·min-1) performed three maximal incremental tests for the determination of iV̇ O2 max(R). iV̇ O2 max was also determined during each test as: (a) the intensity determined by extrapolation of the submaximal intensity-V̇ O2 relationship (Method 1); (b) the minimum intensity at which V̇ O2 max was attained (Method 2); (c) the ratio of V̇ O2 max to the oxygen cost of submaximal exercise (C) (Method 3); (d) the ratio of (V̇ O2 max - V̇ O2 at rest) to (C - V̇ O2 at rest) (Method 4); and (e) the highest intensity sustained for 3 min (Method 5). Methods 1, 2, and 4 produced iV̇ O2 max values that were not significantly different from iV̇ O2 max(R) (P<0.05). The iV̇ O2 max values of Method 3 (P = 0.01) and Method 5 (P = 0.04) were significantly greater than iV̇ O2 max(R). Methods 1, 2, and 4 provide good estimates of the minimum exercise intensity at which V̇ O2 max is elicited and therefore may be useful when setting interval training intensities. In contrast, methods 3 and 5 appear to overestimate iV̇ O2 max. [ABSTRACT FROM AUTHOR]

Purpose: To extend currently available sex and age-specific normative values in children and adolescents for the peak work rate (WRpeak) attained at the steep ramp test (SRT) to healthy active young adults.Methods: Healthy male and female participants aged between 19 and 24 years were recruited. After screening and anthropometric measurements, participants performed a SRT on a cycle ergometer (increments of 25 W/10 s), monitoring and recording SRT-WRpeak, heart rate (HR), and blood pressure (BP) at rest and directly after peak exercise.Results: Fifty-seven participants (31 males and 26 females; median age of 21.3 years) volunteered and were tested. Anthropometrics, resting BP and lung function were all within normal ranges. Ninety-three percent of the participants attained a peak HR (HRpeak) > 80% of predicted (mean HRpeak 87 ± 5% of predicted). No differences were found in resting and peak exercise variables between females and males, except for absolute SRT-WRpeak (350 W [Q1: 306; Q3: 371] and 487 W [Q1: 450; Q3: 517], respectively) and SRT-WRpeak normalized for body mass (relative SRT-WRpeak; 5.4 ± 0.5 and 6.2 ± 0.6 W/kg, respectively). Low-to-moderate correlations (ρ [0.02-0.71]) were observed between SRT-WRpeak and anthropometric variables for females and males separately. Extended reference curves (8-24-year-old subjects) for SRT performance show different trends between male and female subjects when modelled against age, body height, and body mass.Conclusions: The present study provides sex-, age-, body height-, and body mass-related normative values (presented as reference centiles) for absolute and relative SRT performance throughout childhood and early adulthood. [ABSTRACT FROM AUTHOR]

The purpose of this experiment was to learn whether low doses of caffeine have ergogenic, perceptual, and metabolic effects during cycling. To determine the effects of 1, 2, and 3 mg/kg caffeine on cycling performance, differentiated ratings of perceived exertion (D-RPE), quadriceps pain intensity, and metabolic responses to cycling exercise, 13 cyclists exercised on a stationary ergometer for 15 min at 80% VO2peak, then, after 4 min of active recovery, completed a 15-min performance ride 60 min after ingesting caffeine or placebo. Work done (kJ/kg) during the performance ride was used as a measure of performance. D-RPE, pain ratings, and expired-gas data were obtained every 3 min, and blood lactate concentrations were obtained at 15 and 30 min. Compared with placebo, caffeine doses of 2 and 3 mg/kg increased performance by 4% (95% CI: 1.0-6.8%, p = .02) and 3% (95% CI: -0.4% to 6.8%, p = .077), respectively. These effects were ergogenic, on average, but varied considerably in magnitude among individual cyclists. There were no effects of caffeine on D-RPE or pain throughout the cycling task. Selected metabolic variables were affected by caffeine, consistent with its known actions. The authors conclude that caffeine preparations of 2 and 3 mg/kg enhanced performance, but future work should aim to explain the considerable interindividual variability of the drug's ergogenic properties. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the effects of purified oxygenated water on exercise performance under hypoxic conditions. Nine recreational male cyclists (age = 26.6 ± 5.2 y, weight = 87.6 ± 19.5 kg, VO2peak = 46.5 ± 5.9 mL · kg-1 · min-1) completed two 600 kJ cycling time trials under hypoxic conditions (FIO2 = 13.6% O2, Pbar = 641 mmHg) separated by 2 wk. Trials were completed following 3 d ingestion of 35 mL · kg-1 · d-1 of control (CON) or experimental (EXP) water. Time to completion, heart rate (HR), rate of perceived exertion (RPE), pulse oximetry (SaO2), blood gases (PcO2 and PcCO2), and lactate were measured during the trials. Hydration was assessed with pre- and post-exercise body weight and 24-h urine specific gravity. Performance, hydration, and blood oxygenation were unaffected by EXP water. Results of this study suggest that purified oxygenated water does not improve exercise performance in moderately active males. [ABSTRACT FROM AUTHOR]

Abstract Cardiopulmonary exercise testing (CPET) modalities, treadmill (TM), and cycle ergometer (CE), influence maximal gas exchange and heart rate (HR) responses. Little is known regarding CPET modality effect on submaximal biomarkers during childhood and adolescence. Ninety‐four healthy participants (7–34 y.o., 53% female) performed TM and CE CPET to address two major gaps: (1) the effect of modality on submaximal CPET biomarkers, and (2) estimation of work rate in TM CPET. Breath‐by‐breath gas exchange enabled calculation of linear regression slopes such as V˙O2/ΔHR and ΔV˙E/ΔV˙CO2. Lean body mass (LBM) was measured with dual X‐ray absorptiometry. We tested a novel TM CPET estimate of work rate based on TM velocity2, incline, and body mass (VIM). Like the linear relationship between V˙O2 and work rate in CE CPET, V˙O2 increased linearly with TM VIM. TM ΔV˙O2/ΔHR was highly correlated with CE (r = 0.92), and each increased substantially with LBM (P