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Around 5.5–6.5 months of age, infants first attend to object size and perceive its mass cues in simple collision events. Infants attend to the size of the moving object and expect a greater displacement following a collision with a large object and stationary object, and lesser displacement following a collision with a small object and stationary object. It has been proposed that infants of 6-to-7 months of age can differentiate between sizes of moving objects but do not perceive the size and mass relationships in simple collision events. The present two investigations aimed to investigate whether infants 10-to-11 months of age (N = 16) could perceive this relationship (experiment 1) and the reverse of this relationship (experiment 2) utilising the looking time paradigm. The reverse of this relationship entailed the circumstances in which the moving object size was kept constant, but the stationary object size varied (small or large). Results from these experiments revealed that infants did not differ in their looking times for size congruent and size incongruent distances in both conditions. Infants did not look longer at the incongruent test events that violated expectation. For that reason, we conclude infants of 10-to-11 months of age were unable to perceive size and mass associations in collision events in either direction (moving object or stationary object size). [ABSTRACT FROM AUTHOR]

Background: Controversy over treatment for people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a barrier to appropriate treatment. Energy management or pacing is a prominent coping strategy for people with ME/CFS. Whilst a definitive definition of pacing is not unanimous within the literature or healthcare providers, it typically comprises regulating activity to avoid post exertional malaise (PEM), the worsening of symptoms after an activity. Until now, characteristics of pacing, and the effects on patients' symptoms had not been systematically reviewed. This is problematic as the most common approach to pacing, pacing prescription, and the pooled efficacy of pacing was unknown. Collating evidence may help advise those suffering with similar symptoms, including long COVID, as practitioners would be better informed on methodological approaches to adopt, pacing implementation, and expected outcomes. Objectives: In this scoping review of the literature, we aggregated type of, and outcomes of, pacing in people with ME/CFS. Eligibility criteria: Original investigations concerning pacing were considered in participants with ME/CFS. Sources of evidence: Six electronic databases (PubMed, Scholar, ScienceDirect, Scopus, Web of Science and the Cochrane Central Register of Controlled Trials [CENTRAL]) were searched; and websites MEPedia, Action for ME, and ME Action were also searched for grey literature, to fully capture patient surveys not published in academic journals. Methods: A scoping review was conducted. Review selection and characterisation was performed by two independent reviewers using pretested forms. Results: Authors reviewed 177 titles and abstracts, resulting in 17 included studies: three randomised control trials (RCTs); one uncontrolled trial; one interventional case series; one retrospective observational study; two prospective observational studies; four cross-sectional observational studies; and five cross-sectional analytical studies. Studies included variable designs, durations, and outcome measures. In terms of pacing administration, studies used educational sessions and diaries for activity monitoring. Eleven studies reported benefits of pacing, four studies reported no effect, and two studies reported a detrimental effect in comparison to the control group. Conclusions: Highly variable study designs and outcome measures, allied to poor to fair methodological quality resulted in heterogenous findings and highlights the requirement for more research examining pacing. Looking to the long COVID pandemic, our results suggest future studies should be RCTs utilising objectively quantified digitised pacing, over a longer duration of examination (i.e. longitudinal studies), using the core outcome set for patient reported outcome measures. Until these are completed, the literature base is insufficient to inform treatment practises for people with ME/CFS and long COVID. [ABSTRACT FROM AUTHOR]

Introduction:The aim of this investigation was to examine the impact high-intensity interval training (HIIT) on serum insulin-like growth factor-I (IGF-I) in active compared with sedentary aging men. Methods:22 lifetime sedentary (SED; 62 ± 2 years) and 17 masters’ athletes (LEX; 60 ± 5 years) were recruited to the study. As HIIT requires preconditioning exercise in sedentary cohorts, the study required three assessment phases; enrollment (phase A), following preconditioning exercise (phase B), and post-HIIT (phase C). Serum IGF-I was determined by electrochemiluminescent immunoassay. Results:IGF-I was higher in LEX compared to SED at baseline (p = 0.007, Cohen’sd = 0.91), and phase B (p = 0.083, Cohen’sd = 0.59), with only a small difference at C (p = 0.291, Cohen’sd = 0.35). SED experienced a small increase in IGF-I following preconditioning from 13.1 ± 4.7 to 14.2 ± 6.0 μg·dl−1(p = 0.376, Cohen’sd = 0.22), followed by a larger increase post-HIIT (16.9 ± 4.4 μg·dl−1), which was significantly elevated compared with baseline (p = 0.002, Cohen’sd = 0.85), and post-preconditioning (p = 0.005, Cohen’sd = 0.51). LEX experienced a trivial changes in IGF-I from A to B (18.2 ± 6.4 to 17.2 ± 3.7 μg·dl−1[p = 0.538, Cohen’sd = 0.19]), and a small change post-HIIT (18.4 ± 4.1 μg·dl−1[p = 0.283, Cohen’sd = 0.31]). Small increases were observed in fat-free mass in both groups following HIIT (p < 0.05, Cohen’sd = 0.32–0.45). Conclusions:In conclusion, HIIT with preconditioning exercise abrogates the age associated difference in IGF-I between SED and LEX, and induces small improvements in fat-free mass in both SED and LEX. [ABSTRACT FROM PUBLISHER]

Introduction: Advancing age is associated with a gradual decline in circulating androgens, and the putative role of exercise training on systemic androgens remains to be adequately defined.Methods: The present investigation examined the impact of 6 weeks of supervised exercise training on resting levels of systemic hormones in a cohort of lifelong sedentary men [SED (n = 28), 62.5 ± 5.3 years], compared with a positive control group of age-matched lifelong exercisers [LE (n = 20), 60.4 ± 4.7 years, >30 years training history]. Blood hormones were sampled pre- and post-intervention from an antecubital forearm vein and analysed using electrochemiluminescent immunoassay. Cardiorespiratory fitness ([Formula: see text]) was determined via indirect calorimetry during an incremental cycle test to volitional exhaustion.Results: Analysis of variance (ANOVA) revealed a lack of significant change in any parameter amongst LE, whilst SED experienced a significant exercise-induced improvement in cardiorespiratory fitness and total testosterone (all p < 0.05). Concurrent increases in sex hormone-binding globulin (SHBG; p < 0.05) resulted in a lack of change to either bioavailable or calculated free testosterone (p > 0.05) amongst SED.Conclusions: Although resting levels of systemic total testosterone increased in response to 6 weeks of exercise training, increases in SHBG negated any potential relationship between calculated-free or bioavailable testosterone. These findings indicate that increases in bioavailable testosterone fraction are not required for cardiorespiratory fitness improvements in aging men. [ABSTRACT FROM AUTHOR]

Testosterone (T) is a biologically important androgen that demonstrates a widely-known natural decline with advancing age. The use of salivary T (sal-T), as a determinant of systemic T, has shown promising results in recent years. However, the strength of the salivary-serum T relationship may be affected by measurement method and binding capacity with salivary proteins. The potential influence exercise may impact on this relationship is unstudied in aging men. Therefore, the aim of the present investigation was to examine the relationship of the delta change (Δ) in sal-T with Δserum T following six weeks exercise training. Fifteen sedentary (SED) males (aged 60.4 ± 5.0 years of age) and 20 lifelong exercising (LE) males (60.4 ± 4.7 years of age) were participated. Pearson's correlation coefficient revealed sal-T did not correlate with total testosterone (TT), sex hormone binding globulin (SHBG), bioactive T (bio-T), or free T (free-T) at week 0 or week 6. Δsal-T did not correlate with ΔTT, ΔSHBG, Δbio-T or Δfree-T ( r = 0.271, p = 0.180; r = 0.197, p = 0.335; r = 0.258, p = 0.205; and r = 0.257, p = 0.205, respectively). In conclusion, poor levels of agreement existed between saliva and serum measurements of T in response to exercise amongst aging men. [ABSTRACT FROM AUTHOR]

Introduction: Advancing age in men is associated with a progressive decline in serum testosterone (T) and interactions between exercise, aging and androgen status are poorly understood. The primary aim of this study was to establish the influence of lifelong training history on serum T, cortisol (C) and sex hormone binding globulin (SHBG) in aging men. A secondary aim was to determine the agreement between serum and salivary measurement of steroid hormones in ageing men. Methods: Serum and salivary steroid hormones (serum C, T and SHBG, and salivary measures of C and T) were determined and compared between two distinct groups; lifelong exercising males (LE [ n = 20], 60.4 ± 4.7 year) and age matched lifelong sedentary individuals (SED [ n = 28], 62.5 ± 5.3 years). Results: T-test revealed a lack of significant differences for serum C or SHBG between LE and SED, while Mann-Whitney U revealed a lack of differences in total T (TT), bioavailable T (bio-T) or free testosterone (free-T). Further, salivary T (sal-T) did not correlate with serum markers of T in LE, SED, or when pooled ( r = 0.040; p > 0.05). Conclusions: Findings from this investigation suggested that resting levels of serum T and calculated free-T was unable to distinguish between diverse lifelong training histories in aging men. Further, sal-T was not an appropriate indicator of serum T and calculated free-T values in older males and considerable caution should be exercised when interpreting sal-T measurements in aging males. [ABSTRACT FROM AUTHOR]

Diurnal variation of sports performance usually peaks in the late afternoon, coinciding with increased body temperature. This circadian pattern of performance may be explained by the effect of increased core temperature on peripheral mechanisms, as neural drive does not appear to exhibit nycthemeral variation. This typical diurnal regularity has been reported in a variety of physical activities spanning the energy systems, from Adenosine triphosphate-phosphocreatine (ATP-PC) to anaerobic and aerobic metabolism, and is evident across all muscle contractions (eccentric, isometric, concentric) in a large number of muscle groups. Increased nerve conduction velocity, joint suppleness, increased muscular blood flow, improvements of glycogenolysis and glycolysis, increased environmental temperature, and preferential meteorological conditions may all contribute to diurnal variation in physical performance. However, the diurnal variation in strength performance can be blunted by a repeated-morning resistance training protocol. Optimal adaptations to resistance training (muscle hypertrophy and strength increases) also seem to occur in the late afternoon, which is interesting, since cortisol and, particularly, testosterone (T) concentrations are higher in the morning. T has repeatedly been linked with resistance training adaptation, and higher concentrations appear preferential. This has been determined by suppression of endogenous production and exogenous supplementation. However, the cortisol (C)/T ratio may indicate the catabolic/anabolic environment of an organism due to their roles in protein degradation and protein synthesis, respectively. The morning elevated T level (seen as beneficial to achieve muscle hypertrophy) may be counteracted by the morning elevated C level and, therefore, protein degradation. Although T levels are higher in the morning, an increased resistance exercise–induced T response has been found in the late afternoon, suggesting greater responsiveness of the hypothalamo-pituitary-testicular axis then. Individual responsiveness has also been observed, with some participants experiencing greater hypertrophy and strength increases in response to strength protocols, whereas others respond preferentially to power, hypertrophy, or strength endurance protocols dependent on which protocol elicited the greatest T response. It appears that physical performance is dependent on a number of endogenous time-dependent factors, which may be masked or confounded by exogenous circadian factors. Strength performance without time-of-day–specific training seems to elicit the typical diurnal pattern, as does resistance training adaptations. The implications for this are (a) athletes are advised to coincide training times with performance times, and (b) individuals may experience greater hypertrophy and strength gains when resistance training protocols are designed dependent on individual T response. (Author correspondence: ) [ABSTRACT FROM AUTHOR]

This study examined the effect of exercise- and heat-induced dehydration on strength, jump capacity and neuromuscular function. Twelve recreationally active males completed six resistance exercise bouts (baseline and after each 5 exposure sessions) in an increasing state of hypohydration obtained by repeated heat exposure and exercise sessions (5 periods of 20 min jogging at up to approximately 80% age predicted heart rate maximum at 48.5 +/- 0.48 degrees C, relative humidity 50 +/- 4%). Relative to starting values, body mass decreased 1.0 +/- 0.5, 1.9 +/- 0.7, 2.6 +/- 0.8, 3.3 +/- 0.9 and 3.9 +/- 1.0% after exposure 1, 2, 3, 4 and 5, respectively. However, plasma volume remained constant. No significant differences existed amongst trials in vertical jump height, electromyography data or isokinetic leg extension at a rate of 120 degrees s(-1). Isometric leg extensions were significantly reduced (P < 0.05) after the first (1% body mass loss) and subsequent exposures in comparison to baseline. Isokinetic leg extensions at a rate of 30 degrees s(-1) were significantly reduced after the third (2.6% body mass loss) and subsequent exposures compared with baseline. No dose response was identified in any of the tested variables yet a threshold was observed in isometric and isokinetic strength at 30 degrees s(-1). In conclusion, dehydration caused by jogging in the heat had no effect on vertical jumping or isokinetic leg extensions at a rate of 120 degrees s(-1). Alternatively, exercise-induced dehydration was detrimental to isometric and isokinetic leg extensions at a rate of 30 degrees s(-1), suggesting the force-velocity relationship in hypohydration merits further research. [ABSTRACT FROM AUTHOR]

Long-term implications of acutely increased cardiorespiratory fitness following short-term exercise interventions in older adults are unknown. In this study, we examined peak oxygen uptake (VO 2peak) after 4-years of 'free-living' after a high intensity interval training (HIIT) intervention. Seventeen lifelong exercisers (LEX) and 17 previously sedentary (SED) males (55–74 years of age in 2012) were tested four years (phase D) after our previous experiment which included 6-weeks of aerobic moderate intensity exercise (phase B), followed by 6-weeks of HIIT (phase C). At all stages, a standard incremental exercise protocol on a cycle ergometer was completed to determine VO 2peak. SED (P = 1.000, Cohen's d = 0.01) and LEX (P = 1.000, Cohen's d = 0.11) VO 2peak at phase D was not different from phase A (enrolment). SED experienced a large decrease in VO 2peak from phase C to phase D (32 ± 6 ml·kg·min−1 to 27 ± 6 ml·kg·min−1 [P < 0.001, Cohen's d = 0.81]). LEX experienced a small decrease in VO 2peak from phase C to phase D (42 ± 7 ml·kg·min−1 to 39 ± 9 ml·kg·min−1 [P < 0.001, Cohen's d = 0.46]). At phase D, LEX had greater VO 2peak than SED (P < 0.001, Cohen's d = 1.73). The proportion of subjects who reported discontinuing training, maintaining moderate training, and maintaining HIIT differed between groups (P = 0.023), with LEX self-reporting more HIIT, and SED self-reporting more discontinuation from exercise. Those who continued exercising experienced a reduction in VO 2peak over the four years from 39 ± 7 ml·kg·min−1 to 36 ± 9 ml·kg·min−1 (N = 25, P < 0.001, Cohen's d = 0.37), and those who discontinued exercising also experienced a reduction in VO 2peak from 30 ± 7 ml·kg·min−1 to 25 ± 9 ml·kg·min−1 (N = 9, P = 0.003, Cohen's d = 0.62). Four years after completing a brief period of aerobic exercise and HIIT, older males demonstrated a preservation of VO 2peak , irrespective of training status (LEX or SED). However, LEX exhibited greater VO 2peak than SED after 4-years of unsupervised 'free-living'. Notably, participants who discontinued exercising experienced a greater reduction in VO 2peak. These data suggest that a 6 weeks of supervised HIIT can facilitate the long term. • 12 weeks of aerobic and HIIT preserved VO 2peak over four years. • This combination increased and maintained VO 2peak in the short- and long-term. • Short-term increased VO 2peak appears a catalyst for maintained VO 2peak over years. • VO 2peak was preserved irrespective of initial exercise training status. • Lifelong exercisers had higher VO 2peak throughout compared with sedentary older men. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether 6 weeks' high intensity interval training (HIIT; 6 × 30 s sprints at 40% peak power, once every five days) following 6 weeks' of aerobic preconditioning could favourably affect fasting insulin, glucose, and the homeostatic model assessment of insulin resistance (HOMA1-IR) in sedentary older men compared with masters athletes. A secondary aim was to establish whether lifelong exercisers (LEX) exhibited improved fasting insulin, glucose, and HOMA1-IR, compared to sedentary older males (SED). Twenty-two males (62 ± 2 years) comprised the SED group and 17 males (60 ± 5 years) were enrolled as LEX. Participants were tested at phase A (baseline), B (after preconditioning), and C (post-HIIT). There was no effect of time (P = 0.116) or interaction (P = 0.727) on insulin. However, there was an effect of group (P < 0.001). In terms of magnitude, HIIT induced a small decrease in SED insulin compared to baseline (15.8 ± 8.1 uIU·ml−1 at baseline and 14.0 ± 7.8 uIU·ml−1 post-HIIT; Cohen's d = 0.23) and compared to post-preconditioning (17.5 ± 9.7 uIU·ml−1; Cohen's d = 0.40). LEX insulin was unchanged throughout (all differences were trivial). Insulin was lower in LEX than SED at phase A (P < 0.001, Cohen's d = 1.31), B (P = 0.023, Cohen's d = 0.78), and C (P = 0.004, Cohen's d = 1.01). There was no effect of time (P = 0.290), group (P = 0.166), or interaction (P = 0.153) for glucose. In terms of magnitude, HIIT produced a small reduction in SED glucose compared to baseline (5.7 ± 1.3 mmol·l−1 at baseline and 5.3 ± 0.9 mmol·l−1 post-HIIT; Cohen's d = 0.36), and compared to phase B (5.6 ± 0.8 mmol·l−1, Cohen's d = 0.35). LEX glucose was unchanged throughout (all changes were trivial). SED had moderately higher blood glucose than LEX at phase A (Cohen's d = 0.49), and B (Cohen's d = 0.63), but only a trivial difference existed at phase C (Cohen's d = 0.15). There was no effect of time (P = 0.110), or interaction (P = 0.569) on HOMA1-IR. However, there was an effect of group (P = 0.002). In terms of magnitude, SED HOMA1-IR was unchanged from phase A to B (4.2 ± 3.0 and 4.5 ± 2.9 arbitrary units respectively [Cohen's d = 0.10]). However, at C (3.5 ± 2.6) there was a small decrease compared to B (Cohen's d = 0.36), and A (Cohen's d = 0.25). LEX experienced a small increase in HOMA1-IR from phase A to B (1.6 ± 1.3 and 2.3 ± 2.8 respectively [Cohen's d = 0.32]), followed by a small decrease from B to C (1.7 ± 1.1 at phase C [Cohen's d = 0.28]), and a trivial change from A to C (Cohen's d = 0.08). HOMA1-IR was lower in LEX than SED at baseline (P = 0.002, Cohen's d = 1.12), after preconditioning (P = 0.024, Cohen's d = 0.77), and post-HIIT (P = 0.014, Cohen's d = 0.90). Results of this study provide preliminary evidence that HIIT preceded by preconditioning can induce small improvements in fasting insulin, glucose, and HOMA1-IR in sedentary older men compared with masters athletes. • HIIT induced a small reduction in fasting insulin in sedentary older men. • HIIT produced a small decrease in fasting glucose in sedentary older men. • HIIT caused a small improvement in HOMA-IR in sedentary older men. • Few individuals improved clinical status (diabetic, impaired fasting glucose) with HIIT. • Lifelong exercisers had superior glucoregulatory biomarkers than sedentary males. [ABSTRACT FROM AUTHOR]

This investigation explored relationships between biological maturation, physical and academic performance in young male soccer players. Thirty-eight players (age: 9.79 ± 1.21 years; body mass index (BMI): 20.4 ± 2.39 kg/m2; body fat: 16.8 ± 2.21%) participated. Measures of anthropometry used for body mass, body fat percentage (%BF), and BMI as well. Postural control, 15 m sprint, squat jumps and counter-movement jumps (SJ, CMJ), and T-half test for change-of-direction (CoD) were parameters of physical performance. The grade point average (GPA) of mathematics determined academic attainment. Moore's equations were used to estimate their maturity status (PHV). Biological maturation was highly correlated with most (not 15 m sprint) physical and academic performance parameters, especially CMJ (r = -0.812) and mathematics (r = -0.781). Academic performance showed the largest relations to the jumping performance (CMJ: r = 0.771; SJ: r = 0.723). In contrast, anthropometric and fatness parameters were not relevantly (r ≥ 0.5) correlated with any other parameters. The largest correlations were calculated for sitting height vs. SJ (r = -0.408), sitting height vs. postural control (r = -0.355), leg length vs. postural control (r = -0.339). As a result, it is essential to take biological maturation inconsideration while assessing the physical and academic achievement of young soccer players. In consequence, soccer coaches and physical education (PE) teachers should be cognizant of the impact of biological maturity on physical and academic performance to assist fair and equal opportunities for achievement in young players. [ABSTRACT FROM AUTHOR]

The response Lawrence D. Hayes, Gordon F. Bickerstaff and Julien S. Baker to a letter to the editor about their article "Interactions of Cortisol, Testosterone, and Resistance Training: Influence of Circadian Rhythms," in the 2010 issue is presented.

The current study examine the effects of combined sprint and resistance training on serum total testosterone (TT), sex-hormone-binding globulin (SHBG) and cortisol (C), at rest, and in response to the Wingate Anaerobic-Test (WAnT) in 21 and 41 years old men. Forty moderately-trained men were randomly assigned to a young trained (YT), young control (YC), middle-aged trained (MAT), and middle-aged control (MAC) group. Before (P1), and after (P2) training, blood samples were collected at rest and after exercise. At P1, higher C and lower TT was observed in middle-aged groups compared to younger ones (P < 0.05). At P2, basal TT increased significantly (P < 0.05) in MAT and the age-difference was absent between trained groups (P > 0.05). Basal SHBG decreased significantly in YT at P2 (P < 0.05) but did not change in other groups from before to after training (P > 0.05). Free-testosterone was significantly (P < 0.05) higher in young compared to middle-aged groups at P1, but at P2, this age-related difference disappeared between YT and MAT (P > 0.05). C post-WAnT increased significantly for MAT only (P < 0.05) at P2, whilst no significant changes were observed in the other three groups (P < 0.05) at P2. In contrast, resting levels of C did not change in all groups at P2 (P > 0.05). The current study demonstrates that this training intervention may help increase steroids hormones in middle-aged men and counteract the negative effect of age on TT and free testosterone. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to compare serum growth hormone (GH), insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-binding protein-3 (IGFBP-3) in response to a combined sprint and resistance training (CSRT) program in young and middle-aged men.Thirty-eight healthy, moderately trained men participated in this study. Young and middle-aged men were randomly assigned to, a young training group (YT = 10, 21.4±1.2yrs) ora young control group (YC = 9, 21.6±1.8 yrs), a middle-aged training group (MAT = 10, 40.4±2.1 yrs) or a middle-aged control group (MAC = 9, 40.5±1.8 yrs). Participants performed the Wingate Anaerobic Test (WAnT) before and after a 13-week CSRT program (three sessions per week). Blood samples were collected at rest, after warm-up, immediately post-WAnT, and 10 min post-WAnT. CSRT induced increases in GH at rest and in response to the WAnT in YT and MAT (P<0.05). CSRT-induced increases were observed for IGF-1 and IGFBP-3 at rest in MAT only (P<0.05). Pre-training, GH, IGF-1 and IGFBP-3 were significantly higher at rest and in response to the WAnT in young participants as compared to their middle-aged counterparts (P<0.05). Post-training, YT and MAT had comparable basal GH (P>0.05). In response to the WAnT, amelioration of the age-effect was observed between YT and MAT for IGF-1 and IGF-1/IGFBP-3 ratio following CSRT (P>0.05). These data suggest that CSRT increases the activity of the GH/IGF-1 axis at rest and in response to the WAnT in young and middle-aged men. In addition, CSRT reduces the normal age-related decline of somatotropic hormones in middle-age men. [ABSTRACT FROM AUTHOR]

Older adults exhibit a reduced number and function of CD34 + circulating progenitor cells (CPC), a known risk factor for cardiovascular disease. Exercise promotes the mobilisation of CPCs from bone marrow, so whether ageing per se or physical inactivity in older age reduces CPCs is unknown. Thus, this study examined the effect of age on resting and exercise-induced changes in CPCs in aerobically trained adults and the effect of 8 weeks of sprint interval training (SIT) on resting and exercise-induced CPCs in older adults. Twelve young (22–34 years) and nine older (63–70 years) adults participated in the study. Blood was sampled pre and immediately post a graded exercise test to exhaustion in both groups. Older participants repeated the process after 8 weeks of SIT (3 × 20 s 'all-out' sprints, 2 × a week). Total CPCs (CD34+) and endothelial progenitor cells (EPCs: CD34+KDR+) were determined by flow cytometry. Older adults exhibited lower basal total CD34+ CPCs (828 ± 314 vs. 1186 ± 272 cells·mL−1, p = 0.0149) and CD34+KDR+ EPCs (177 ± 128 vs. 335 ± 92 cells·mL−1, p = 0.007) than younger adults. The maximal exercise test increased CPCs in young (CD34+: p = 0.004; CD34+KDR+: p = 0.017) and older adults (CD34+: p < 0.001; CD34+KDR+: p = 0.008), without difference between groups (p = 0.211). SIT did not alter resting or exercise-induced changes in CPCs in the older cohort (p > 0.232). This study suggests age per se does not impair exercise-induced CPC counts, but does lower resting CPC counts. [ABSTRACT FROM AUTHOR]

Aims: Aerobic exercise is well recognised as an effective treatment for people with type 2 diabetes but the optimal amount of aerobic exercise to improve glycaemic control remains to be determined. Thus, the aim of this meta-analysis and meta-regression was to assess the impact of volume and intensity of aerobic exercise on glycaemic control. Methods: Medline, Cochrane, Embase, and Web of Science databases were searched up until 15 December 2020 for the terms "aerobic exercise AND glycaemic control", "type 2 diabetes AND exercise", and "exercise AND glycaemic control AND Type 2 diabetes AND randomised control trial". We included (i) randomised control trials of ≥ 12 weeks, (ii) trials where participants had type 2 diabetes and were aged 18 or over, and (iii) the trial reported HbA1c concentrations pre- and post-intervention. Two reviewers selected studies and extracted data. Data are reported as standardised mean difference (SMD) and publication bias was assessed using funnel plots. Results: A total of 5364 original titles were identified. Sixteen studies were included in the meta-analysis. Aerobic exercise reduced HbA1c versus control (SMD = 0.56 (95% CI 0.3–0.82), p < 0.001). There were also significant reductions in BMI (SMD = 0.76 (95% CI 0.25–1.27), p < 0.05). There was no dose–response relationship between improvement in HbA1c and the intensity and volume of the intervention (p > 0.05). Conclusions: Twelve-week or longer aerobic exercise programmes improve glycaemic control and BMI in adults with type 2 diabetes. Longer or more intense interventions appear to confer no additional benefit on HbA1c. [ABSTRACT FROM AUTHOR]

Background: Ageing is accompanied by decreases in physical capacity and physiological regulatory mechanisms including altered hormonal regulation compared with age-matched sedentary people. The potential benefits of exercise in restoring such altered hormone production and secretion compared to age-matched physically inactive individuals who are ageing remains unclear. Objectives: The aim of this systematic review was to summarise the findings of exercise training in modulating levels of ostensibly anabolic and catabolic hormones in adults aged > 40 years. Methods: We searched the following electronic databases (to July 2021) without a period limit: Cochrane Library, PubMed, Science Direct, Scopus, SPORTDiscus and Web of Science. Additionally, a manual search for published studies in Google Scholar was conducted for analysis of the 'grey literature' (information produced outside of traditional commercial or academic publishing and distribution channels). The initial search used the terms 'ageing' OR 'advanced age' OR 'old people' OR 'older' OR elderly' AND 'anabolic hormones' OR 'catabolic hormones' OR 'steroid hormones' OR 'sex hormones' OR 'testosterone' OR 'cortisol' OR 'insulin' OR 'insulin-like growth factor-1' OR 'IGF-1' OR 'sex hormone-binding globulin' OR 'SHBG' OR 'growth hormone' OR 'hGH' OR 'dehydroepiandrosterone' OR 'DHEA' OR 'dehydroepiandrosterone sulfate (DHEA-S)' AND 'exercise training' OR 'endurance training' OR 'resistance training' OR ' strength training' OR 'weight-lifting' OR 'high-intensity interval training' OR 'high-intensity interval exercise' OR 'high-intensity intermittent training' OR 'high-intensity intermittent exercise' OR 'interval aerobic training' OR 'interval aerobic exercise' OR 'intermittent aerobic training' OR 'intermittent aerobic exercise' OR 'high-intensity training' OR 'high-intensity exercise' OR 'sprint interval training' OR 'sprint interval exercise' OR 'combined exercise training' OR 'anaerobic training'. Only eligible full texts in English or French were considered for analysis. Results: Our search identified 484 records, which led to 33 studies for inclusion in the analysis. Different exercise training programs were used with nine studies using endurance training programs, ten studies examining the effects of high-intensity interval training, and 14 studies investigating the effects of resistance training. Most training programs lasted ≥ 2 weeks. Studies, regardless of the design, duration or intensity of exercise training, reported increases in testosterone, sex hormone-binding globulin (SHBG), insulin-like growth factor-1 (IGF-1), human growth hormone (hGH) or dehydroepiandrosterone (DHEA) (effect size: 0.19 < d < 3.37, small to very large) in both older males and females. However, there was no consensus on the effects of exercise on changes in cortisol and insulin in older adults. Conclusion: In conclusion, findings from this systematic review suggest that exercise training increases basal levels of testosterone, IGF-1, SHBG, hGH and DHEA in both male and females over 40 years of age. The increases in blood levels of these hormones were independent of the mode, duration and intensity of the training programs. However, the effects of long-term exercise training on cortisol and insulin levels in elderly people are less clear. [ABSTRACT FROM AUTHOR]

This creative-relational inquiry explores the lived experience of people suffering from Long Covid. Responding to calls for a publicly oriented qualitative inquiry, we collaborate across an extended project team to develop and share an accessible and engaging performance text which advocates for and supports those who live precariously as a result of contracting Long Covid. We offer our performance text as a resource to inform and guide personal, professional, public, and policy responses to Long Covid. We propose that creative-relational inquiries such as this beneficially extend understanding beyond what is possible through traditional evidence-based medicine alone. [ABSTRACT FROM AUTHOR]

Purpose: The present study aimed to investigate the effect of age on circulating pro- and anti-inflammatory cytokines and growth factors. A secondary aim was to investigate whether a novel sprint interval training (SIT) intervention (3 × 20 s 'all out' static sprints, twice a week for 8 weeks) would affect inflammatory markers in older men.Methods: Nine older men [68 (1) years] and eleven younger men [28 (2) years] comprised the younger group. Aerobic fitness and inflammatory markers were taken at baseline for both groups and following the SIT intervention for the older group.Results: Interleukin (IL)-8, vascular endothelial growth factor (VEGF), and monocyte chemoattractant protein-1 (MCP-1) were unchanged for the older and younger groups at baseline (IL-8, p = 0.819; MCP-1, p = 0.248; VEGF, p = 0.264). Epidermal growth factor (EGF) was greater in the older group compared to the younger group at baseline [142 (20) pg mL-1 and 60 (12) pg mL-1, respectively, p = 0.001, Cohen's d = 1.64]. Following SIT, older men decreased EGF to 100 (12) pg mL-1 which was similar to that of young men who did not undergo training (p = 0.113, Cohen's d = 1.07).Conclusion: Older aerobically trained men have greater serum EGF than younger aerobically trained men. A novel SIT intervention in older men can shift circulating EGF towards trained younger concentrations. As lower EGF has previously been associated with longevity in C. elegans, the manipulative effect of SIT on EGF in healthy ageing in the human may be of further interest. [ABSTRACT FROM AUTHOR]

Attenuated performance during intense exercise with limited endogenous carbohydrate (CHO) is well documented. Therefore, this study examined whether caffeine (CAF) mouth rinsing would augment performance during repeated sprint cycling in participants with reduced endogenous CHO. Eight recreationally active males (aged 23 ± 2 yr, body mass 84 ± 4 kg, stature 178 ± 7 cm) participated in this randomized, single-blind, repeated-measures crossover investigation. Following familiarization, participants attended two separate evening glycogen depletion sessions. The following morning, participants completed five, 6 s sprints on a cycle ergometer (separated by 24 s active recovery), with mouth rinsing either (1) a placebo solution or (2) a 2% CAF solution. During a fifth visit, participants completed the sprints without prior glycogen depletion. Repeated-measures ANOVA identified significant main effect of condition (CAF, placebo, and control [P < .05; effect size (ES) = 0.850–0.897]), sprint (1–5 [P < .005; ES = 0.871–0.986]), and interaction (condition × sprint [P < .05; ES = 0.831–0.846]), for peak and mean power. The control condition exhibited the highest peak power (overall mean 760 ± 77 W) and mean power (overall mean 699 ± 83W) over the five sprints (P < .001 in both instances). CAF peak power (overall mean 643 ± 79 W) was significantly greater than placebo (mean 573 ± 79 W [P < .05; ES = 0.850]). Additionally, CAF mean power (overall mean 589 ± 80 W) was significantly greater than placebo (519 ± 82 W [P < .05; ES = 0.397]). These data indicate that mouth rinsing a caffeinated solution reduces decrements caused by CHO reduction, which may benefit athletes wishing to train in a low-CHO state. [ABSTRACT FROM PUBLISHER]

Although considerable research concerning the efficacy of analgesics in sport exists, there is a paucity of data concerning effects of acute acetaminophen (ACT) ingestion on sprint interval running exercise. This investigation concerned the effect of acute ACT ingestion on eight 30 s maximal treadmill sprints on a non-motorized treadmill, interspersed with two-minute rests in males (N=8, age 26±3 years, body height 174±7 cm, body mass 71±8 kg) in a placebo-controlled, randomized crossover design. A time x condition repeated measures analysis of variance (ANOVA) determined ACT ingestion did not influence mean power output, peak power output, peak vertical ground reaction force, peak oxygen uptake, or total distance completed (p>.05). Perceived pain was reduced by 8-15% during the final three sprints following ACT ingestion (p<.05). Data presented here suggest ACT may reduce exercise-induced pain during the latter stages of sprint interval treadmill running, without influencing performance. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effect of acute acetaminophen (ACT) ingestion on eight maximal 30-second cycling bouts, interspersed with two-minute rests. Seven recreationally active females (N=7, 22.8±6.7 years of age, with a stature of 163.4±5.8 cm, and body mass of 58.9±5.9 kg) participated in a placebo-controlled, randomized crossover design. Pain perception, heart rate, and power profiles were analyzed using a time x condition repeated measures ANOVA. Blood lactate after the eighth bout and total work done were analyzed using the paired samples t-test. Participants achieved a significantly greater (p=.007, =.725) peak power output during the ACT trials (402.9±73.8 W, 95% CI=334.6–471.1 W) when compared to the placebo (PLA) trials (378.7±64.6 W, 95% CI=319.0–438.4 W). Supplementation of ACT had no effect on mean power output, blood lactate accumulation, pain perception, or total work done after eigth bouts (p>.05). Data presented here suggest females can improve peak power output during repeated Wingate tests with ACT ingestion. It is proposed that the altered afferent feedback may have caused these alterations in power output. [ABSTRACT FROM AUTHOR]