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Peak oxygen uptake ( V ˙ O 2 ) is internationally recognized as the criterion measure of youth aerobic fitness, but flawed laboratory assessments and fallacious interpretations of peak V ˙ O 2 in ratio with body mass have confused our understanding of the development of aerobic fitness. Moreover, the recent emergence of specious predictions of peak V ˙ O 2 from performance tests and the promotion of spurious "clinical red flags" and cardiometabolic cut-points have confused our understanding of the relationship between youth aerobic fitness and health. Recent longitudinal studies of 10–18-year-olds using multilevel allometric modeling have empirically demonstrated that peak V ˙ O 2 increases in accord with sex-specific, concurrent changes in age- and maturity status-driven morphological covariates with the timing and tempo of changes specific to individuals. During both cycle ergometry and treadmill running age- and maturity status- driven changes in fat free mass have been revealed as the most powerful morphological influences on the development of youth aerobic fitness. To bring some clarity to current confusion, this paper argues that future studies must be founded on rigorous assessment and interpretation of peak V ˙ O 2 and ensure that they address the development of youth aerobic fitness and its relationship with present and future health in relation to appropriate sex-specific morphological covariates governed by individual biological clocks. [ABSTRACT FROM AUTHOR]

Rationale:The prognostic value of cardiopulmonary exercise testing (CPET) for survival in cystic fibrosis (CF) in the context of current clinical management, when controlling for other known prognostic factors, is unclear. Objectives: To determine the prognostic value of CPET-derived measures beyond peak oxygen uptake (VO2peak) following rigorous adjustment for other predictors. Methods: Data from 10 CF centers in Australia, Europe, and North America were collected retrospectively. A total of 510 patients completed a cycle CPET between January 2000 and December 2007, of which 433 fulfilled the criteria for a maximal effort. Time to death/lung transplantation was analyzed using Cox proportional hazards regression. In addition, phenotyping using hierarchical Ward clustering was performed to characterize high-risk subgroups. Measurements and Main Results: Cox regression showed, even after adjustment for sex, FEV1% predicted, body mass index (z-score), age at CPET, Pseudomonas aeruginosa status, and CF-related diabetes as covariates in themodel, that VO2 peak in % predicted (hazard ratio [HR], 0.964; 95% confidence interval [CI], 0.944–0.986), peak work rate (% predicted; HR, 0.969; 95% CI, 0.951–0.988), ventilatory equivalent for oxygen (HR, 1.085; 95% CI, 1.041–1.132), and carbon dioxide (HR, 1.060; 95% CI, 1.007–1.115) (all P , 0.05) were significant predictors of death or lung transplantation at 10-year follow-up. Phenotyping revealed that CPET-derived measures were important for clustering. We identified a high-risk cluster characterized by poor lung function, nutritional status, and exercise capacity. Conclusions: CPET provides additional prognostic information to established predictors of death/lung transplantation in CF. High-risk patients may especially benefit from regular monitoring of exercise capacity and exercise counseling. [ABSTRACT FROM AUTHOR]

Rationale: The main purposes of this study were to compare mitochondrial respiration in M. triceps brachii and M. vastus lateralis between elite cross-country (XC) skiers and physically active controls (CON), and to explore the associations between mitochondrial respiration in these muscles and peak oxygen uptake (V ˙ O2peak) in arm- and leg-dominant exercise modes. Methods: Thirteen male elite XC skiers (age: 25 ± 4; peak oxygen uptake (V ˙ O2peak): 75.5 ± 4.2 mL⋅kg-1⋅min-1) and twelve CON (age: 26 ± 3; V ˙ O2peak: 57.2 ± 6.4 mL⋅kg-1⋅min-1) had microbiopsies taken from M. vastus lateralis and M. triceps brachii, which were analyzed for various measures of mitochondrial respiration using high-resolution respirometry. Thereafter, all participants tested V ˙ O2peak in both running (RUN) and upper body poling (UBP). Results: XC skiers had generally higher mitochondrial respiration in M. triceps brachii compared to CON (P < 0.001), whereas no significant group-differences in mitochondrial respiration in M. vastus lateralis were revealed. XC skiers had higher mitochondrial respiration in M. triceps brachii compared to M. vastus lateralis (P = 0.005–0.058), whereas in CON, most mitochondrial respiration measures were higher in M. vastus lateralis than in M. triceps brachii (P < 0.01). When all athletes were pooled, there was a strong positive correlation between V ˙ O2peak in UBP and mitochondrial respiration in M. triceps brachii on several measures (P < 0.01), whereas no correlation was found for RUN. Conclusion: The higher mitochondrial respiration found in M. triceps brachii compared to M. vastus lateralis among our elite XC skiers demonstrates the potential for the arm muscles to adapt to aerobic endurance training. The opposite pattern found in CON, clearly showed lower mitochondrial respiration in M. triceps brachii compared to XC skiers, whereas respiration in M. vastus lateralis did not differ between groups. The strong positive correlation between mitochondrial respiration in M. triceps brachii and V ˙ O2peak in UBP indicate that arm muscles' respiratory function may be a limiting factor for V ˙ O2peak in arm-dominant exercise modes. [ABSTRACT FROM AUTHOR]

Abstract Anandamide, a major endocannabinoid, participates in energy metabolism homeostasis and neurobehavioral processes. In a secondary analysis of an open-label, randomized controlled trial, we investigated the long-term effect of aerobic exercise on resting plasma anandamide, and explored its relationship with changes in body weight, cardiorespiratory fitness, and mood status in healthy, physically inactive individuals. Participants recruited between March 2013 to August 2015 at the UNIFESP's Neurology/Psychobiology Department were randomly allocated into a 12-weeks supervised moderate exercise program, or into waitlist, control condition. Thirty-four participants (age = 38 ± 11.5, BMI = 26.6 ± 3.6) were intention to treat-analysed (Exercise: n = 17; Control: n = 17). After intervention, there were significant decreases in plasma anandamide (p <.01), anger, anxiety, and body weight (all p <.05), whereas cardiorespiratory fitness increased (p <.05) in the exercise group. There were no significant changes in any variable for the control group. In the whole cohort, adjusted R2 of multiple linear regressions showed that 12.2% of change body weight was explained by changes in anandamide (β = 0.391, p =.033), while 27% of change in mood disturbance (β = 0.546, p =.003), and 13.1% of change in anger (β = 0.404, p =.03) was explained by changes in anandamide. Our data suggest that the weight loss and mood improvement through regular moderate exercise may involve changes in anandamide metabolism/signaling. Trials registration: #NCT01972607. Highlights • Regular moderate aerobic exercise training promotes reduction of plasma anandamide. • Lower anandamide after exercise was associated with weight loss and improved mood. • Exercise training may modulate the peripheral and central actions of anandamide. [ABSTRACT FROM AUTHOR]

Purpose: To describe the Norwegian Ullevaal model, customised for cardiac patients in primary care, and to evaluate the feasibility of the model through patient outcomes after the 12 week outpatient cardiac rehabilitation programme. Materials and methods: A descriptive interventional cohort study with pre-post design. Patients referred to cardiac rehabilitation (n = 273) were enrolled. Group-based high-intensity interval training was offered twice weekly. The primary outcome measure was change in peak oxygen uptake. Quality of life was measured using the COOP-WONCA questionnaire. Results: A total of 87% completed the 12 weeks exercise based rehabilitation programme and there were no adverse events during testing or exercise training. Peak oxygen uptake improved significantly from 31.6 ± 7.5 to 34.1 ± 7.8 ml/kg/min. Mean difference was 4.1 ml/kg/min (95% confidence interval, 3.74.5). COOP-WONCA was significantly improved in all domains. Conclusions: The Norwegian Ullevaal model was effective and safe, and resulted in significant and clinically meaningful improvements in cardiopulmonary fitness and quality of life. Implications for rehabilitation: Cardiac rehabilitation programmes giving at least 3.5 ml/kg/min improvements of peak oxygen uptake are shown to be beneficial. The detailed description of the Norwegian Ullevaal model, applied as a cardiac rehabilitation programme in primary care, may help clinicians with planning and initiating of group-based high intensity cardiac rehabilitation, as well as implementing evidence based science into practice. The findings from this study provide preliminary evidence in support of alternative exercise prescriptions compared to present modalities for cardiac rehabilitation in primary care. [ABSTRACT FROM AUTHOR]

Aims: Exercise-derived parameters, specifically peak exercise oxygen uptake (peak VO2 ) and minute ventilation/carbon dioxide relationship slope (VE/VCO2 slope), have a pivotal prognostic value in heart failure (HF). It is unknown how the prognostic threshold of peak VO2 and VE/VCO2 slope has changed over the last 20 years in parallel with HF prognosis improvement.Methods and Results: Data from 6083 HF patients (81% male, age 61 ± 13 years), enrolled in the MECKI score database between 1993 and 2015, were retrospectively analysed. By enrolment year, four groups were generated: group 1 1993-2000 (n = 440), group 2 2001-2005 (n = 1288), group 3 2006-2010 (n = 2368), and group 4 2011-2015 (n = 1987). We compared the 10-year survival of groups and analysed how the overall risk (cardiovascular death, urgent heart transplantation, or left ventricular assist device implantation) changed over time according to peak VO2 and VE/VCO2 slope and to major clinical and therapeutic variables. At 10 years, a progressively higher survival from group 1 to group 3 was observed, with no further improvement afterwards. A 20% risk for peak VO2 15 mL/min/kg (95% confidence interval 16-13), 9 (11-8), 4 (4-2) and 5 (7-4) was observed in group 1, 2, 3, and 4, respectively, while the VE/VCO2 slope value for a 20% risk was 32 (37-29), 47 (51-43), 59 (64-55), and 57 (63-52), respectively.Conclusions: Heart failure prognosis improved over time up to 2010 in a HF population followed by experienced centres. The peak VO2 and VE/VCO2 slope cut-offs identifying a definite risk progressively decreased and increased over time, respectively. The prognostic threshold of peak VO2 and VE/VCO2 slope must be updated whenever HF prognosis improves. [ABSTRACT FROM AUTHOR]

To evaluate the magnitude of the difference in VO2peak between patients with Chronic Fatigue Syndrome/ Myalgic Encephalomyelitis (CFS/ME) and apparently healthy controls, 7 databases (Cochrane, PubMed, PsycINFO, Web of Knowledge, Embase, Scopus, Medline) were searched for articles published up to March 2018. Search terms included "chronic fatigue syndrom * "AND ("peak" OR "maxim*" OR "max") AND ("oxygen uptake" OR "oxygen consumption" OR "VO2peak" or "VO2max". Eligibility criteria were adults > 18 y with clinically diagnosed CFS/ME, with VO2peak measured in a maximal test and compared against an apparently healthy control group. The methodological quality of included studies was assessed using a modified Systematic Appraisal of Quality for Observational Research critical appraisal framework. A random effects meta-analysis was conducted on 32 cross-sectional studies (effects). Pooled mean VO2peak was 5.2 (95 % CI: 3.8-6.6) ml. kg-1min-1 lower in CFS/ME patients vs. healthy controls. Between- study variability (Tau) was 3.4 (1.5-4.5) ml.kg-11min-1 indicating substantial heterogeneity. The 95 % prediction interval was - 1.9 to 12.2 ml.kg-1min-1 . The probability that the effect in a future study would be > the minimum clinically important difference of 1.1 ml.kg-1mi-1 (in favour of controls) was 0.88 -- likely to be clinically relevant. Synthesis of the available evidence indicates that CFS/ME patients have a substantially reduced VO2peak compared to controls. [ABSTRACT FROM AUTHOR]

Summary: Aortic valve surgery is the definitive treatment for aortic stenosis (AS). No specific recommendation is available on how exercise training should be conducted and evaluated after aortic valve replacement (AVR). This study aimed to examine the effect of aerobic exercise training on exercise capacity following AVR. In addition to our primary outcome variable, peak oxygen uptake (peakVO2), the effect on submaximal cardiopulmonary variables including oxygen uptake kinetics (tau), oxygen uptake efficiency slope (OUES) and ventilatory efficiency (VE/VCO2 slope) was evaluated. Following AVR due to AS, 12 patients were randomized to either a group receiving 12 weeks of supervised aerobic exercise training (EX) or a control group (CON). Exercise capacity was assessed by a maximal cardiopulmonary exercise test (CPET). There was a significant increase in peak load (+28%, P = 0·031) and in peakVO2 (+23%, P = 0·031) in EX, corresponding to an increase in achieved percentage of predicted peakVO2 from 88 to 104% (P = 0·031). For submaximal variables, there were only non‐statistically significant trends in improvement between CPETs in EX. In CON, there were no significant differences in any maximal or submaximal variable between CPETs. We conclude that 12 weeks of supervised aerobic exercise training induces significant adaptations in cardiopulmonary function following AVR, especially in regard to maximal variables including peakVO2. In addition, we provide novel data on the effect on several submaximal variables following exercise training in this group of patients. [ABSTRACT FROM AUTHOR]

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Background and objective: Low levels of cardiorespiratory fitness are associated with a high risk of cardiovascular disease (CVD) and all-cause mortality in women. The aim of this study was to determine the validity of a 500-m moderate treadmill-walking test for estimating peak oxygen uptake (VO2peak) in older women with CVD.Methods: Fifty-three women with stable CVD (age 70.4 ± 8.2 years) underwent exercise testing during an outpatient cardiac rehabilitation/secondary prevention program. Each patient completed a maximal cardiopulmonary exercise test, and a moderate and self-paced (11-13/20 on the Borg scale) 500-m treadmill-walking test. Treadmill walk time, age, weight, height, and heart rate during the test were entered into prediction equations previously validated for VO2peak estimation in male patients.Results: Measured and estimated VO2peak values were not different (20.8 ± 4.3 vs 21.3 ± 4.6 mL/kg/min, P = 0.12). The comparison between measured and estimated VO2peak values yielded a correlation of R = 0.92 (SEE = 1.3 mL/kg/min, P < 0.0001), with the slope and the intercept that coincided with the line of identity (Passing and Bablok analysis, P = 0.65). Residuals were normally distributed with a mean value of − 0.5 mL/kg/min. Examination of the Bland-Altman analysis does not show systematic or proportional error.Conclusion: A moderate and self-regulated 500-m treadmill-walking test is a valid tool for VO2peak estimation in older women with CVD. These findings may have practical implications in the context of transitioning from clinically based programs to fitness facilities or self-guided exercise programs in older women with stable cardiovascular disease. [ABSTRACT FROM AUTHOR]

PurposeThe growth effects of exercise appear to be mediated in part by central neuroendocrine control reflected in circulating levels of growth hormone (GH), insulin-like growth factor-I (IGF-I), and their binding proteins (BP). In previous studies positive correlations between peak VO2 and circulating IGF-I have been demonstrated. The relationship between peak oxygen uptake and these potential regulating factors has not been examined in adolescent males where patterns of GH pulsatility and levels of IGF-I are rapidly changing.MethodsForty-three healthy adolescent males (age 16 +/- 0.7 yr, 70% at Tanner V) performed cycle ergometry to determine p oxygen uptake (peak VO2), and magnetic resonance images to determine the thigh muscle volume. Baseline blood samples were collected for GHBP, the extracellular portion of the GH tissue receptor (by ligand mediated immunofunctional assay), IGF-I (by RIA), and IGFBPs 1-5 (by RIA). Mean GH was determined from samples obtained every 20 min overnight.ResultsPeak VO2/kg was positively correlated with mean overnight GH levels (r = 0.41, P < 0.005). Both peak VO2/kg and thigh muscle volume/kg were negatively correlated with GHBP (r = -0.33, P < 0.02) and IGFBP-4 (r = -0.52, P < 0.005). There were no correlations between peak VO2/kg and IGF-I or IGFBPs 1-3, and 5.ConclusionsGH pulsatility is increased adolescent males who have higher peak VO2, but this did not translate into increases in IGF-I. We speculate that in the fitter males, lower GHBP levels may reduce hepatic sensitivity to GH. Thus, circulating IGF-I was unchanged despite higher mean GH in subjects with higher peak VO2. IGFBP-4 which is known to inhibit IGF-I was negatively correlated with peak VO2 leading, possibly, to increased IGF-I bioactivity. Fitness (as assessed by muscle mass and peak VO2) does modulate the GH-IGF-I axis, but not solely through circulating IGF-I; both GHBP and IGFBPs play important roles.

PurposeThe growth effects of exercise appear to be mediated in part by central neuroendocrine control reflected in circulating levels of growth hormone (GH), insulin-like growth factor-I (IGF-I), and their binding proteins (BP). In previous studies positive correlations between peak VO2 and circulating IGF-I have been demonstrated. The relationship between peak oxygen uptake and these potential regulating factors has not been examined in adolescent males where patterns of GH pulsatility and levels of IGF-I are rapidly changing.MethodsForty-three healthy adolescent males (age 16 +/- 0.7 yr, 70% at Tanner V) performed cycle ergometry to determine p oxygen uptake (peak VO2), and magnetic resonance images to determine the thigh muscle volume. Baseline blood samples were collected for GHBP, the extracellular portion of the GH tissue receptor (by ligand mediated immunofunctional assay), IGF-I (by RIA), and IGFBPs 1-5 (by RIA). Mean GH was determined from samples obtained every 20 min overnight.ResultsPeak VO2/kg was positively correlated with mean overnight GH levels (r = 0.41, P < 0.005). Both peak VO2/kg and thigh muscle volume/kg were negatively correlated with GHBP (r = -0.33, P < 0.02) and IGFBP-4 (r = -0.52, P < 0.005). There were no correlations between peak VO2/kg and IGF-I or IGFBPs 1-3, and 5.ConclusionsGH pulsatility is increased adolescent males who have higher peak VO2, but this did not translate into increases in IGF-I. We speculate that in the fitter males, lower GHBP levels may reduce hepatic sensitivity to GH. Thus, circulating IGF-I was unchanged despite higher mean GH in subjects with higher peak VO2. IGFBP-4 which is known to inhibit IGF-I was negatively correlated with peak VO2 leading, possibly, to increased IGF-I bioactivity. Fitness (as assessed by muscle mass and peak VO2) does modulate the GH-IGF-I axis, but not solely through circulating IGF-I; both GHBP and IGFBPs play important roles.

Abstract Aims: To describe the relationship between variables related to body composition and peak oxygen uptake ( V ˙ O 2peak) and to verify whether fat mass can affect these relationships. Methods: Eighty participants underwent cardiopulmonary exercise testing to measure V ˙ O 2peak and a body composition assessment to measure fat mass, fat free mass (FFM), and total body mass (BM). Results: There were significant relationships between V ˙ O 2peak relative to FFM (fat free mass) (mL/kgFFM/min) and absolute fat mass (kg) (r=-0.50, p

Background: High-intensity interval training (HIIT) is as a time-efficient alternative to moderate- or low-intensity continuous exercise for improving variables related to endurance and anaerobic performance in young and adolescent athletes.Objectives: To assess original research about enhancement of endurance and anaerobic exercise performance in young and adolescent athletes performing HIIT.Method: Relevant articles published in peer-reviewed journals were retrieved from the electronic databases PubMed and SPORTDiscus in December 2017. Inclusion criteria were: (i) controlled trials (HIIT vs. alternative training protocol) with pre-post design; (ii) healthy young athletes (≤18 years); (iii) assessing variables related to endurance and exercise performance. Hedges' g effect size (ES), and associated 95% confidence intervals were calculated for comparison of any outcome between experimental (HIIT) and alternative training protocol.Results: Twenty four studies, involving 577 athletes (mean age: 15.5 ± 2.2 years), were included in this review. HIIT exerted no or small positive mean ES on peak oxygen uptake (VO2peak), running performance, repeated sprint ability, jumping performance and submaximal heart rate. Although the mean ES for changes in VO2peak with HIIT is small (mean g = 0.10±0.28), the average increase in VO2peak from pre to post HIIT-interventions were 7.2 ± 6.9% vs. 4.3 ± 6.9% with any other alternative intervention. HIIT largely and positively affected running speed and oxygen consumption at various lactate- or ventilatory-based thresholds, as well as for sprint running performance. Calculations showed negative mean ES for change-of-direction ability (large), and peak blood lactate concentrations (small). Mean duration per training session for HIIT was shorter than for control interventions (28 ± 15 min vs. 38 ± 24 min).Conclusion: The present findings suggest that young athletes performing HIIT may improve certain important variables related to aerobic, as well as anaerobic, performance. With HIIT, most variables related to endurance improved to a higher extent, compared to alternative training protocols. However, based on ES, HIIT did not show clear superiority to the alternative training protocols. Nevertheless, young athletes may benefit from HIIT as it requires less time per training session leaving more time for training sport specific skills.

In mountain climbing, short pre-exposure to hypoxia at the midway point of a high mountain is often carried out before heading to a higher altitude. However, the effects of such exposure have not been examined experimentally. This study aimed at investigating the effects of short pre-exposure to hypoxia on physiological responses to subsequent hypoxic exercise. Thirteen male sea-level residents participated in 2 tests. Both tests consisted of 60-min normobaric exposure followed by 15-min stepwise incremental ergocycle exercise (five workloads) under hypoxic conditions (fractional inspired oxygen concentration [FiO2] = 0.167). Conditions during normobaric exposure were hypoxic (FiO2 = 0.167) or normoxic (FiO2 = 0.209). Results of the two-way analysis of variance (oxygen concentration × exercise intensity) showed significant oxygen concentration effects on heart rate (HR), carbon dioxide production (VCO2), and rating of perceived exertion during hypoxic exercise. Significant interaction effects were found in minute ventilation and VCO2. Post hoc tests compared these parameters after hypoxic exposure with those after normoxic exposure at each workload, and only showed a significant difference in HR at workload 2. A significant negative correlation was observed between peak oxygen uptake (VO2) measured in normoxia and ratio of arterial oxygen saturation (SpO2) after hypoxic exposure to that after normoxic exposure at workload 5. The present study could not clearly show through post hoc tests the significant effects of short hypoxic pre-exposure on physiological responses to subsequent hypoxic exercise, while it indicated that those with relatively higher peak VO2 showed a greater decrease in SpO2 during hypoxic exercise after hypoxic exposure than after normoxic exposure.

Purpose: To investigate performance-determining variables of an on-snow sprint cross-country skiing competition and the evolvement in their relationship with performance as the competition progresses from the individual time trial (TT) to the final., Methods: Sixteen national-level male junior skiers (mean [SD] age, 18.6 [0.8] y; peak oxygen uptake [VO2peak], 67.6 [5.5] mL·min-1·kg-1) performed a simulated sprint competition (1.3 km) in the skating style, comprising a TT followed by 3 finals (quarterfinals, semifinals, and final) completed by all skiers. In addition, submaximal and incremental roller-ski treadmill tests, on-snow maximal speed tests, and strength/power tests were performed., Results: VO2peak and peak treadmill speed during incremental testing and relative heart rate, rating of perceived exertion, blood lactate concentrations, and gross efficiency during submaximal testing were all significantly correlated with performance in the TT and subsequent finals (mean [range] r values: .67 [.53-.86], all P < .05). Relative VO2peak and submaximal relative heart rate and blood lactate concentration were more strongly correlated with performance in the semifinals and final compared with the TT (r values: .74 [.60-.83] vs 0.55 [.51-.60], all P < .05). Maximal speed in uphill and flat terrain was significantly correlated with performance in the TT and subsequent finals (r values: .63 [.38-.70], all P < .05), while strength/power tests did not correlate significantly with sprint performance., Conclusions: VO2peak and high-speed abilities were the most important determinants of sprint cross-country skiing performance, with an increased importance of VO2peak as the competition format progressed toward the final.

Reduced exercise capacity has been suggested as a cardinal sequela of COVID-19. However, only cross-sectional approaches that either do not consider individuals with concomitant cardiorespiratory disease or account for exercise capacity before infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) support this assumption. Is reduced exercise capacity a sequela of SARS-CoV-2 infection in patients with concomitant cardiorespiratory disease? We retrospectively reviewed cardiopulmonary exercise testing (CPET) data collected across three hospitals between October 2018 and March 2022. Forty-two patients who completed a CPET before and after COVID-19 and 25 patients who performed two separate CPETs but did not contract COVID-19 (CTL) were included. Within each patient, the same test protocol was performed at the first and second CPETs. The time between CPETs was similar between the groups (COVID-19 489 ± 534 vs. CTL 534 ± 257 days, P = 0.662). The COVID-19 group performed the CPETs 312 ± 232 days before and 176 ± 110 days after infection. Exercise time, peak heart rate, peak systolic pressure, oxygen uptake (V̇o 2 ) at anaerobic threshold, peak ventilation, and ventilatory efficiency were not different between the CPETs in both groups. Peak V̇o 2 was reduced from before to after SARS-CoV-2 infection. However, the change in V̇o 2peak from the first to the second CPET was not different between COVID-19 vs. CTL. Accounting for V̇o 2peak before COVID-19 and including a group of control patients, we find limited evidence for reduced exercise capacity as a sequela of SARS-CoV-2 infection in patients with concomitant cardiorespiratory disease. NEW & NOTEWORTHY There is accumulating evidence that reduced exercise capacity is, or can be, an outcome following COVID-19. However, evidence to date relies upon cross-sectional approaches that either do not consider patients with concomitant cardiorespiratory disease or account for pre-infection exercise capacity data. Accounting for V̇o 2peak before COVID-19 and including a group of control patients, we find limited evidence for reduced exercise capacity as a sequela of SARS-CoV-2 infection in patients with concomitant cardiorespiratory disease.

Introduction: Exercise training is an established intervention method for improving exercise capacity and survival rates in patients with heart failure with preserved ejection fraction (HFpEF). However, most reports have focused on European and American patients, with limited data regarding the effects of exercise training on cardiac function, hemodynamics, and exercise capacity in East Asian patients. This study investigated the effects of exercise training on cardiac function, hemodynamics, and exercise capacity in Japanese patients aged 65-80 years with HFpEF., Methods: This single-center, open-label, non-randomized, controlled trial prospectively enrolled 99 outpatients. Eligibility criteria for HFpEF patients were an HFA score ≥5 in addition to clinical symptoms of heart failure and left ventricular diastolic dysfunction. Exercise training in the intervention group consisted of aerobic exercise and strength training thrice weekly for 5 months. Patients in the control group continued the usual treatment for 5 months. Resting cardiac function was evaluated using echocardiography. Peak oxygen uptake (peakVO 2 ), ventilatory equivalent (VE) vs. carbon dioxide output (VCO 2 ) slope, peak cardiac output index, and arteriovenous oxygen difference were calculated using cardiopulmonary exercise testing combined with impedance cardiography., Results: After 5 months of exercise training, remarkable interactions were observed, with peakVO 2 as the primary outcome. Additionally, significant interactions were observed between hemodynamic indices and some echocardiographic parameters. The mean percentage change in peakVO 2 from baseline was 8.3% in the intervention group. Fifteen study participants (30.1%) in the intervention group achieved a clinically meaningful change of 3.0 ml/min/kg (10% improvement) in peakVO 2 from baseline. The group with 3.0 ml/min/kg or 10% improvement in peakVO 2 from baseline had a considerably lower prevalence of diabetes mellitus and VE vs. VCO 2 slope and considerably higher left atrial-global longitudinal strain values than the group without any notable improvements., Conclusions: Although exercise training can help improve exercise intolerance in Japanese patients aged 65-80 years with HFpEF, its benefits are limited. Our results suggest that HFpEF, complicated by diabetes mellitus and decreased ventilatory efficiency during exercise, may require reconsideration of intervention strategies. This trial was registered with the University Hospital Medical Information Network, a trial registry in Japan (registration number: UMIN000045474)., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Sugita, Ito, Yoshioka, Kudo, Arakawa and Sakai.)

Background: Poor functional capacity has been identified as an important modifiable risk factor for postoperative complications. Cardiopulmonary exercise testing (CPET) provides objective parameters of functional capacity (e.g., oxygen consumption at peak exercise, peak VO 2 ), with significant prognostication for postoperative complications. However, sex-specific thresholds for functional capacity to predict surgical risk are yet to be established. Therefore, we performed a post hoc analysis of the international, multicentre, prospective observational METS (Measurement of Exercise Tolerance before Surgery) study to evaluate if sex-specific thresholds of peak VO 2 improve risk prediction of postoperative complications., Methods: We undertook a post hoc analysis (HREC/71824/PMCC) of the METS study, which was performed between March 2013 and March 2016. We investigated whether sex-specific differences exist for CPET-derived parameters and associated thresholds for predicting postoperative complications in this large cohort of patients that had major non-cardiac surgery (n = 1266). Logistic regression models were analyzed for the association of low peak VO 2 with moderate-to-severe in-hospital postoperative complications. Optimal sex-specific peak VO 2 thresholds were obtained by maximizing the Youden index of receiver operating characteristic (ROC) curves. Finally, multivariable logistic regression models tested the resulting sex-specific thresholds against the established non-sex-specific peak VO 2 threshold (14 mL kg -1 min -1 ) adjusted for clinically relevant features such as comorbidities and surgical complexity. Models were evaluated by bootstrapping optimism-corrected area under the ROC curve and the net reclassification improvement index (NRI)., Findings: Female patients (n = 480) had a lower mean (SD) peak VO 2 than males (16.7 (4.9) mL kg -1 min -1 versus 21.2 (6.5) mL kg -1 min -1 , p < 0.001) and a lower postoperative complication rate (10.4% versus 15.3%; p = 0.018) than males (n = 786). The optimal peak VO 2 threshold for predicting postoperative complications was 12.4 mL kg -1 min -1 for females and 22.3 mL kg -1 min -1 for males, respectively. In the multivariable regression model, low non-sex-specific peak VO 2 did not independently predict postoperative complications. In contrast, low sex-specific peak VO 2 was an independent predictor of postoperative complications (OR 2.29; 95% CI: 1.60, 3.30; p < 0.001). The optimism-corrected AUC-ROC of the sex-specific model was higher compared with the non-sex-specific model (0.73 versus 0.7; DeLong's test: p = 0.021). The sex-specific model classified 39% of the patients more correctly than the baseline model (NRI = 0.39; 95% CI: 0.24, 0.55). In contrast, the non-sex-specific model only classified 9% of the patients more correctly when compared against the baseline model (NRI = 0.09; 95% CI: -0.04, 0.22)., Interpretation: Our data report sex-specific differences in preoperative CPET-derived functional capacity parameters. Sex-specific peak VO 2 thresholds identify patients at increased risk for postoperative complications with a higher discriminatory ability than a sex-unspecific threshold. As such, sex-specific threshold values should be considered in preoperative CPET to potentially improve risk stratification and to guide surgical decision-making, including eligibility for surgery, preoperative optimization strategies (prehabilitation) or seeking non-surgical options., Funding: There was no funding for the present study. The original METS study was funded by Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research, Innovation and Science, UK National Institute of Academic Anaesthesia, UK Clinical Research Collaboration, Australian and New Zealand College of Anaesthetists, and Monash University., Competing Interests: All authors declare no competing interests., (© 2023 The Authors.)

Objective: To evaluate the exercise capacity in patients following Fontan-Kreutzer, Fontan-Björk, and total cavopulmonary connection (TCPC)., Methods: Patients who performed exercise capacity tests at least once after the Fontan procedure between 1979 and 2007 were included. Patients after Fontan-Björk procedure were divided into 2 groups according to the pulmonary blood flow (PBF) pattern: patients with pulsatile PBF and those without. Peak oxygen uptake (VO 2 ) was measured and percent-predicted VO 2 was calculated., Results: A total of 227 patients were nominated. The types of Fontan procedure included Fontan-Kreutzer in 48 (21.1%) patients, Fontan-Björk in 38 (16.7%); 11 (4.8%) with pulsatile PBF and 27 (11.9%) without pulsatile PBF; and TCPC in 141 (62.1%). Median age at the Fontan procedure was 4.5 years (interquartile range, 2.1-8.2 years). A total of 978 cardiopulmonary exercise tests were performed at median follow-up of 17.7 years (interquartile range, 11.3-23.4 years) postoperatively. Analysis using linear mixed-effects models demonstrated that percent-predicted VO 2 was greater in patients with pulsatile PBF after Fontan-Björk compared with patients after other types of Fontan procedure ( P  < .001). The same results were obtained when the longitudinal percent predicted VO 2 was performed using only patients with tricuspid atresia and double inlet left ventricle ( P  < .001)., Conclusions: Among long-term survivors after various types of Fontan procedures, patients with pulsatile PBF after the Fontan-Björk procedure demonstrated better exercise performance compared to those after TCPC, those after the Fontan-Kreutzer procedure, and those after the Fontan-Björk procedure with non-pulsatile PBF. The results implicate the importance of pulsatile PBF to maintain the Fontan circulation., Competing Interests: The authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (© 2023 The Author(s).)

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Abstract: Neuromuscular electrical stimulation (NMES) of large muscle groups in patients with stable chronic heart failure (CHF) increases physical work capacity and muscle strength. The safety and efficacy of short courses of NMES in patients with decompensated CHF has not been studied. The aim of the study was to compare the impact of leg NMES, interval bicycle training, and conventional treatment on the functional capacity and quality of life in patients hospitalized with decompensation of CHF. A total of 51 patients (84.3% of men; mean age, 62.5 ± 3.3 years) hospitalized with decompensated CHF were divided into three groups: optimal pharmacological therapy (OPT) + three weeks of NMES of thigh and shin muscles starting within the first three days after admission (n = 10), OPT + three weeks of bicycle exercise training (BET) starting on the fifth to seventh day (n = 20), and the control group of OPT only (n = 21). At baseline and after the three-week symptom-limited cardiopulmonary exercise test, 6-min walk test, Duke Activity Status Index (DASI) and quality of life assessment by the Minnesota Living with Heart Failure Questionnaire (MLHFQ) were performed. Patients in the NMES and BET groups presented with similar increases in the 6-min walk distance, plus 65.0 (50.0; 112.5) and 53.0 (51.0; 78; 0) m; DASI, plus 8.6 (5.5; 11.8) and 8.0 (4.5; 9.0) points; and VO2peak, plus 1.9 (0.3; 3.2) and 2.2 (0.7; 3.2) mL/(min kg), respectively. In the control group, only the 6-min walk distance increased significantly (+21 m). The improvement in the MLHFQ score was observed in all the three groups: maximal in the BET group and minimal in the NMES group. Three weeks of leg muscle electrical stimulation and bicycle training provide similar improvement in physical capacity, daily activity, and the quality of life in patients hospitalized for severe CHF. The efficacy of NMES is comparable with low to moderate intensity interval bicycle training and well tolerated by patients. [ABSTRACT FROM AUTHOR]

Aim: We assessed whether baseline measurements of physical activity, aerobic fitness, body fat and abdominal fat were predictors of changes in body fat measurements over a two-year period.Methods: The study comprised of 204 children aged 9.8 ± 0.6 years with a normal body mass distribution, who recruited from four schools in middle-class areas of Malmö, Sweden, from 2001 to 2004. Peak oxygen uptake and physical activity were measured at baseline. Body fat was measured by dual-energy X-ray absorptiometry at baseline and two years later.Results: Physical activity, aerobic fitness and total body fat or abdominal fat were predictors of change in total body fat or abdominal fat over a period of two years. Changes in the percentage of body fat were not related to any of the baseline measurements.Conclusion: Our two-year follow-up of children with a mean age of 9.8 years at baseline showed that physical activity, aerobic fitness and body fat or abdominal fat predicted changes in total body fat or abdominal fat, but not the percentage of body fat. [ABSTRACT FROM AUTHOR]

The validity and safety of using supramaximal verification (Smax) to confirm a maximal effort during cardiopulmonary exercise testing (CPET) in people with cystic fibrosis (CF) and/or those with severe disease has been questioned. Therefore, this study aimed to investigate these concerns in children, adolescents, and adults with mild-to-severe CF lung disease. Retrospective analysis of 17 pediatric and 28 adult participants with CF [age range: 9.2-62.9 y; forced expiratory volume in 1 s: 66.7% (range: 29.9%-102.3%); 30 men] who completed a routine ramp-incremental cycling test to determine peak oxygen uptake (V̇o2peak) was studied. Maximal oxygen uptake (V̇o2max) was subsequently confirmed by Smax at 110% of peak power output. All participants satisfied the criteria to verify a maximal effort during CPET. However, Smax-V̇o2peak exceeded ramp-V̇o2peak in 3/14 (21.4%) of pediatric and 6/28 (21.4%) adult exercise tests. A valid measurement of V̇o2max was attained in 85.7% of pediatric and 96.4% of adult exercise tests, as Smax-V̇o2peak did not exceed ramp-V̇o2peak by >9%. Adults ( n = 9) experienced a ≥5% reduction in arterial O2 saturation during CPET, 4 during both the ramp and Smax, 3 during only the ramp, and 2 during only Smax. Smax did not significantly worsen perceived breathing effort, chest tightness, throat narrowing, or exertion compared with ramp-incremental testing. Given the clinical importance of aerobic fitness in people with CF, incorporating Smax is recommended to provide a safe and valid measure of V̇o2max in children, adolescents, and adults who span the spectrum of CF disease severity. NEW & NOTEWORTHY Incorporating supramaximal verification into cardiopulmonary exercise testing protocols did not increase the frequency of adverse events or perceived discomfort versus a single-phase incremental exercise test in people with mild-to-severe cystic fibrosis. Furthermore, a valid measure of maximal oxygen uptake (V̇o2max) was obtained from 85.7% of pediatric and 96.4% of adult exercise tests, whereas peak oxygen uptake underestimated aerobic fitness in comparison with V̇o2max in 21.4% of cases (by up to 24.4%). [ABSTRACT FROM AUTHOR]

Copyright of Salud Uninorte is the property of Fundacion Universidad del Norte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Exercise stress testing has been widely undertaken for the diagnosis of heart diseases. The accurate assessment of clinical conditions can be conducted by comparing the findings obtained from the results of stress echocardiography with the changes in the blood/heart rate and electrocardiograms. Numerous overseas studies have reported the utility of stress echocardiography in diagnosing myocardial ischemia; in Japan, the use of this modality for this purpose was included in the national health insurance reimbursable list in 2012. Nevertheless, stress echocardiography is far from being a widespread practice in Japan. This might be due to insufficient equipment (e.g., ergometers, space for test implementation) at each medical institution, shortage of technicians and sonographers who are well experienced and who are responsible for obtaining images during stress testing. The other possible reasons include the limited evidence available in Japan and the lack of a standardized testing protocol. Further dissemination of the practice of exercise stress echocardiography in this country is deemed necessary to establish satisfactory evidence for the use of stress echocardiography in the Japanese population. To this end, efforts are underway to develop a standardized protocol and report format to be adopted throughout Japan. We here present a guideline created by the Guideline Development Committee of the Japanese Society of Echocardiography that describes safe and effective stress echocardiography protocols and report formats. The readers are encouraged to perform exercise stress echocardiography using the proposed template for consensus document and report attached to this guideline. [ABSTRACT FROM AUTHOR]

We hypothesize that the reduced peak aerobic power (peak V˙O2) after heart transplantation is due to impaired cardiovascular and skeletal muscle function, and its improvement with short-term (≤1 yr) exercise training is primarily due to favorable skeletal muscle adaptations. Furthermore, the increased peak V˙O2 with long-term (>2 yr) training is primarily mediated by cardiac (sympathetic) reinnervation. [ABSTRACT FROM AUTHOR]

Peak oxygen uptake (VO2peak) is commonly indexed by total body weight (TBW) to determine cardiopulmonary fitness (CPF). This approach may lead to misinterpretation, particularly in obese subjects. We investigated the normalization of VO2peak by different body composition markers. We analyzed combined data of 3848 subjects (1914 women; 49.7%), aged 20-90, from two independent cohorts of the population-based Study of Health in Pomerania (SHIP-2 and SHIP-TREND). VO2peak was assessed by cardiopulmonary exercise testing. Body cell mass (BCM), fat-free mass (FFM), and fat mass (FM) were determined by bioelectrical impedance analysis. The suitability of the different markers as a normalization variable was evaluated by taking into account correlation coefficients (r) and intercept (α-coefficient) values from linear regression models. A combination of high r and low α values was considered as preferable for normalization purposes. BCM was the best normalization variable for VO2peak (r = .72; P ≤ .001; α-coefficient = 63.3 mL/min; 95% confidence interval [CI]: 3.48-123) followed by FFM (r = .63; P ≤ .001; α-coefficient = 19.6 mL/min; 95% CI: -57.9-97.0). On the other hand, a much weaker correlation and a markedly higher intercept were found for TBW (r = .42; P ≤ .001; α-coefficient = 579 mL/min; 95% CI: 483 to 675). Likewise, FM was also identified as a poor normalization variable (r = .10; P ≤ .001; α-coefficient = 2133; 95% CI: 2074-2191). Sex-stratified analyses confirmed the above order for the different normalization variables. Our results suggest that BCM, followed by FFM, might be the most appropriate marker for the normalization of VO2peak when comparing CPF between subjects with different body shape. [ABSTRACT FROM AUTHOR]

Copyright of German Journal of Sports Medicine / Deutsche Zeitschrift fur Sportmedizin is the property of Verein zur Forderung der Sportmedizin Hannover e.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Little is known regarding a correlation of hemodynamics at rest or exercise capacity with echocardiographic parameters in patients with pulmonary hypertension (PH). To clarify these potential correlations, we performed transthoracic echocardiography, right heart catheterization, and cardiopulmonary exercise testing in 53 patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). Left ventricular end-diastolic dimension (LVDd), early diastolic velocity of the septal mitral annulus (septal e′), tricuspid regurgitation peak gradient (TRPG), and tricuspid annular plane systolic excursion (TAPSE) were significantly correlated with cardiac index (LVDd; r = 0.477, P < 0.001, septal e′; r = 0.463, P = 0.001, TRPG; r = − 0.455, P = 0.001 and TAPSE; r = 0.406, P = 0.003, respectively). Multiple regression analysis revealed that LVDd and septal e′ were significantly associated with cardiac index (CI) and stroke volume index at rest. Among the exercise capacity markers evaluated, TAPSE, TRPG, and LVDd were significantly correlated with peak oxygen uptake (TAPSE; r = 0.534, P < 0.001, TRPG; r = − 0.466, P = 0.001 and LVDd; r = 0.411, P = 0.002, respectively). Multiple regression analysis showed that TAPSE was significantly associated with peak oxygen uptake (VO2). In PAH and CTEPH patients, LVDd and septal e′ were significantly associated with CI at rest, whereas TAPSE was significantly associated with peak VO2. Echocardiographic parameters may predict the prognostic factors of PAH and CTEPH patients. [ABSTRACT FROM AUTHOR]

Rationale: Cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in human skeletal muscle cells. Variations of CFTR dysfunction among patients with cystic fibrosis may be an important determinant of maximal exercise capacity in cystic fibrosis. Previous studies on the relationship between CFTR genotype and maximal exercise capacity are scarce and contradictory.Objectives: This study was designed to explore factors influencing maximal exercise capacity, expressed as peak oxygen uptake (V.O2peak), with a specific focus on CFTR genotype in children and adults with cystic fibrosis.Methods: In an international, multicenter, cross-sectional study, we collected data on CFTR genotype and cardiopulmonary exercise tests in patients with cystic fibrosis who were ages 8 years and older. CFTR mutations were classified into functional classes I–V.Results: The final analysis included 726 patients (45% females; age range, 8–61 yr; forced expiratory volume in 1 s, 16 to 123% predicted) from 17 cystic fibrosis centers in North America, Europe, Australia, and Asia, all of whom had both valid maximal cardiopulmonary exercise tests and complete CFTR genotype data. Overall, patients exhibited exercise intolerance (V.O2peak, 77.3 ± 19.1% predicted), but values were comparable among different CFTR classes. We did not detect an association between CFTR genotype functional classes I–III and either V.O2peak (percent predicted) (adjusted β = −0.95; 95% CI, −4.18 to 2.29; P = 0.57) or maximum work rate (Wattmax) (adjusted β = −1.38; 95% CI, −5.04 to 2.27; P = 0.46) compared with classes IV–V. Those with at least one copy of a F508del-CFTR mutation and one copy of a class V mutation had a significantly lower V.O2peak (β = −8.24%; 95% CI, −14.53 to −2.99; P = 0.003) and lower Wattmax (adjusted β = −7.59%; 95% CI, −14.21 to −0.95; P = 0.025) than those with two copies of a class II mutation. On the basis of linear regression analysis adjusted for relevant confounders, lung function and body mass index were associated with V.O2peak.Conclusions: CFTR functional genotype class was not associated with maximal exercise capacity in patients with cystic fibrosis overall, but those with at least one copy of a F508del-CFTR mutation and a single class V mutation had lower maximal exercise capacity. [ABSTRACT FROM AUTHOR]

Cardiopulmonary exercise testing ( CPET) is the gold standard among clinical exercise tests. It combines a conventional stress test with measurement of oxygen uptake ( VO2) and CO2 production. No validated Swedish reference values exist, and reference values in women are generally understudied. Moreover, the importance of achieved respiratory exchange ratio ( RER) and the significance of breathing reserve ( BR) at peak exercise in healthy individuals are poorly understood. We compared VO2 at maximal load (peak VO2) and anaerobic threshold ( VO2@ AT) in healthy Swedish individuals with commonly used reference values, taking gender into account. Further, we analysed maximal workload and peak VO2 with regard to peak RER and BR. In all, 181 healthy, 50-year-old individuals (91 women) performed CPET. Peak VO2 was best predicted using Jones et al. (100·5%), while SHIP reference values underestimated peak VO2 most: 112·5%. Furthermore, underestimation of peak VO2 in women was found for all studied reference values ( P<0·001) and was largest for SHIP: women had 128% of predicted peak VO2, while men had 104%. Peak VO2 was similar in subjects with peak RER of 1-1·1 and RER > 1·1 (2 328·7 versus 2 176·7 ml min−1, P = 0·11). Lower BR (≤30%) related to significantly higher peak VO2 ( P<0·001). In conclusion, peak VO2 was best predicted by Jones. All studied reference values underestimated oxygen uptake in women. No evidence for demanding RER > 1·1 in healthy individuals was found. A lowered BR is probably a normal response to higher workloads in healthy individuals. [ABSTRACT FROM AUTHOR]

Increased plasma pro-inflammatory and decreased anti-inflammatory cytokines have been implicated in physiological and behavioural aspects of mood- and pain-related disorders, including migraine. In this case-control study, we assessed mood scores, cardiorespiratory fitness (VO 2Peak ), and plasma concentrations of TNF-α, IL-1β, IL-6, IL-8, IL-10, and IL-12p70 interictally in women with episodic migraine with/without aura (ICHD-II), taking no preventive medicine, and in healthy women recruited from São Paulo Hospital and local community, respectively. Thirty-seven participants (mean ± SD age = 34 ± 10 and BMI = 26.5 ± 4.9) were assessed. Groups (Control, n = 17; Migraine, n = 20) showed no differences in age, BMI, and VO 2Peak . Migraine patients showed higher tension ( p = 0.019) and anxiety scores ( p = 0.046), TNF-α ( p < 0.01), and IL-12p70 (p = 0.01), while IL-6 (p < 0.01), IL-8 (p < 0.01), and IL-10 (p < 0.01) were decreased compared to control group. Multiple linear regression models showed that migraine was positively associated with TNF-α and IL-12p70, and negatively associated with IL-6, IL-8, and IL-10. Anxiety scores were positively associated with IL-12p70, and VO 2Peak was negatively associated with TNF-α. In conclusion, an exaggeratedly skewed cytokine profile, in particular the TNF-α and 12p70/IL-10 balance may be related to migraine pathomechanisms, and its psychiatric comorbidities and functional capacity. Additional studies are needed to confirm these results. [ABSTRACT FROM AUTHOR]

This study sought to determine the time course of training adaptations to two different sprint interval training programmes with the same sprint: rest ratio (1:8) but different sprint duration. Nine participants (M: 7; F: 2) were assigned to 15-second training group (15 TG) consisting of 4-6 × 15-second sprints interspersed with 2-minute recovery, whereas eight participants (M: 5; F: 3) were assigned to 30-second training group (30 TG) consisting of 4-6 × 30 second sprints interspersed with 4-minute recovery. Both groups performed their respective training twice per week over 9 weeks and changes in peak oxygen uptake () and time to exhaustion ( TTE) were assessed every 3 weeks. Additional eight healthy active adults (M: 6; F: 2) completed the performance assessments 9 weeks apart without performing training (control group, CON). Following 9 weeks of training, both groups improved (15 TG: 12.1%; 30 TG: 12.8%, P<.05) and TTE (15 TG: 16.2%; 30 TG: 12.8%, P<.01) to a similar extent. However, while both groups showed the greatest gains in at 3 weeks (15 TG: 16.6%; 30 TG: 17.0%, P<.001), those in TTE were greatest at 9 weeks. CON did not change any of performance variables following 9 weeks. This study demonstrated that while the changes in cardiorespiratory function plateau within several weeks with sprint interval training, endurance capacity ( TTE) is more sensitive to such training over a longer time frame in moderately-trained individuals. Furthermore, a 50% reduction in sprint duration does not diminish overall training adaptations over 9 weeks. [ABSTRACT FROM AUTHOR]

Background: Patients suffering from exercise-induced laryngeal obstruction (EILO) are subjected to several exhausting tests. We aimed to assess the feasibility of using a single test to obtain diagnostic measurements for maximum oxygen uptake (VO2max) and exercise-induced laryngeal obstruction (EILO). Methods: Patients referred to the outpatient respiratory clinic at the University Hospital of Bispebjerg, Copenhagen with exercise-induced dyspnoea were evaluated for inclusion over 13 months. Eligible patients were aged 18–43 years, had a known EILO diagnosis (moderate or severe) and were inactive (self-reported activity) with less than 3 hours activity per week. In randomised order, all participants (n = 11) underwent three tests: a VO2max test with and without concurrent laryngoscopy. VO2max and EILO values from the two testing methods were compared. Findings: There was no difference in VO2max measured by ergospirometry with and without simultaneous continuous laryngoscopy during exercise (CLE) testing (mean difference −22 ml O2･min−1; 95% CI −125 to 81 ml O2･min−1; P = 0.647). EILO scores obtained during the CLE testing on the treadmill versus CLE testing on the ergometer bike revealed identical supraglottic scores in nine of the 11 participants (82%) with substantial agreement between the two types of test (x = 0.71). Glottic scores were identical in six of the 11 (55%), showing moderate agreement between test types (x = 0.38). Conclusions: Based on our findings in inactive individuals, ergospirometry with laryngoscopy is feasible and well tolerated, yielding measurements for maximal oxygen uptake comparable to those of standard bike ergospirometry. Likewise, measurements of supraglottic EILO are comparable to those of the standard treadmill CLE test.

Purpose: To investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry (DEXA) in Japanese subjects. Methods: A total of 93 men (42.2 ± 12.3 years old) and 106 women (43.5 ± 12.3 years old) were enrolled in this cross-sectional investigation study. Peak oxygen uptake was measured by the breath-by-breath method. Regional body composition i.e., body fat mass, lean body mass, and body fat percentage was evaluated using DEXA. In addition, metabolic risk parameters were also evaluated. Results: Peak oxygen uptake was 37.6 ± 8.7 mL/kg/min in men and 31.1 ± 6.4 mL/kg/min in women, and decreased with age in both genders. Peak oxygen uptake was significantly correlated with total body fat percentage (men: r = −0.684, p