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Background: The pre-season preparatory period is considered key for optimizing the physical fitness levels needed to withstand congested match periods and preventing injuries during the regular soccer season. This study contrasted the effects s of neuromuscular training (NMT) versus an endurance-dominated training (ET) program conducted during the preseason on measures of physical fitness and injury occurrence in female soccer players. Methods: Twenty-four female soccer players aged 17.0 ± 1.3 years from a professional soccer club participated in this study. Players were randomly assigned to NMT (n = 12) or ET (n = 12) groups according to their playing position. The preseason intervention program lasted six weeks, with three weekly sessions with a duration of 45–60 min per session. Exercises in the NMT group included muscle strengthening exercises, plyometrics, agility and dynamic stability exercises, while the ET group practiced a traditional pre-season training program consisting of running and sprinting exercises, fartlek, and high-intensity interval training. The training volumes were similar in the two study groups. Anthropometric measurements, physical fitness tests (i.e., linear and change-of-direction speed, muscle strength and power tests) and the overall injury rate per 1000 h of exposure (training, match) were recorded throughout the season. Results: No between group differences were found at pre (T1). Significant group-by-time interactions were observed for the 5, 10, and 30-m linear sprint speed tests (p < 0.001, 2.16 < d < 2.58), the T-test (p = 0.024, d = 1.03), the squat (p < 0.001, d = 4.04), and the countermovement jump test (p < 0.001, d = 2.21), the Loughborough soccer passing test (LSPT) (p = 0.019, d = 1.08), and the 1-RM back squat test (p < 0.001, d = 2.53). Post-hoc tests indicated that NMT provided larger improvements for SJ, CMJ, 1-RM back squat, the 5-m sprint, 10-m sprint, 30-m sprint, T-test and LSPT compared to ET (1.07 > d > 2.77). The injury rate across the season was significantly lower in the NMT (5.1/1000 h exposure) compared to ET (11.8/1000 h exposure) (p = 0.014). Conclusions: The findings support that six-weeks of preseason NMT versus ET induced larger performance improvements, and significantly reduced injury occurrence in elite female soccer players. Key points: • Our results indicate that the integration of 45 to 60 min of preseason neuromuscular training, three times per week, for 6 weeks, can improve physical fitness and prevent injuries in young female soccer players. • The present study demonstrated that the neuromuscular training program can reduce the incidence injury rate by more than 50% and the burden by more than 65% compared to the endurance-dominated training. • Neuromuscular training is an effective approach during the preseason period to improve diverse measures of physical fitness and to reduce injury occurrence. • Preseason neuromuscular training appears to improve the fitness level of female soccer players and as such could allow them to compete at the high level. [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]

Purpose: Animal and human studies have shown that repeated heating may induce skeletal muscle adaptations, increasing muscle strength. The aim of this study is to investigate the effect of 6 weeks of localized heating on skeletal muscle strength, volume and contractile properties in healthy humans.Methods: Fifteen active participants (8 males/7 females, 35 ± 6 years, 70 ± 14 kg, 173 ± 7 cm, average training of 87 min per week) were subjected to 6 weeks of single-leg heat therapy. Heat pads were applied for 8 h/day, 5 days/week, on one randomly selected calf of each participant, while the contralateral leg acted as control. The heat pads increased muscle temperature by 4.6 ± 1.2 °C (p < 0.001). Every 2 weeks, participants were tested for morphological (MRI), architectural (ultrasound), contractile (electrically evoked twitch), and force (isometric and isokinetic) adaptations.Results: Repeated localized heating did not affect the cross-sectional area (p = 0.873) or pennation angle (p = 0.345) of the gastrocnemius muscles; did not change the evoked peak twitch amplitude (p = 0.574) or rate of torque development (p = 0.770) of the plantar flexors; and did not change maximal voluntary isometric (p = 0.214) or isokinetic (p = 0.973) plantar flexor torque.Conclusion: Whereas previous studies have observed improved skeletal muscle function following whole-body and localized heating in active and immobilized humans, respectively, the current data suggested that localized heating may not be a potent stimulus for muscle adaptations in active humans. [ABSTRACT FROM AUTHOR]

Background: Recently, several authors have proposed the use of a submaximal 'perceptually regulated exercise test' (PRET) to predict maximal oxygen uptake ( $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ ). The PRET involves asking the individual to self-regulate a series of short bouts of exercise corresponding to pre-set ratings of perceived exertion (RPE). The individual linear relationship between RPE and oxygen uptake (RPE: $$ \dot{V}{\text{O}}_{2} $$ ) is then extrapolated to the $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ , which corresponds to the theoretical maximal RPE (RPE). Studies suggest that prediction accuracy from this method may be better improved during a second PRET. Similarly, some authors have recommended an extrapolation to RPE rather than RPE. Objectives: The purpose of the meta-analysis was to examine the validity of the method of predicting $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ from the RPE: $$ \dot{V}{\text{O}}_{2} $$ during a PRET, and to determine the level of agreement and accuracy of predicting $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ from an initial PRET and retest using RPE and RPE. Data Sources: From a systematic search of the literature, 512 research articles were identified. Study Eligibility Criteria: The eligible manuscripts were those which used the relationship between the RPE and $$ \dot{V}{\text{O}}_{2} $$ , and used only the Borg's RPE scale. Participants and Interventions: Ten studies ( n = 274 individuals) were included. Study Appraisal and Synthesis Methods: For each study, actual and predicted $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ from four subgroup outcomes (RPE in the initial test, RPE in the retest, RPE in the initial test, RPE in the retest) were identified, and then compared. The magnitude of the difference regardless of subgroup outcomes was examined to determine if it is better to predict $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ from extrapolation to RPE or RPE. The magnitude of differences was examined for the best PRET (test vs retest). Results: The results revealed that $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ may be predicted from RPE: $$ \dot{V}{\text{O}}_{2} $$ during PRET in different populations and in various PRET modalities, regardless of the subgroup outcomes. To obtain greater accuracy of predictions, extrapolation to RPE during a retest may be recommended. Limitations: The included studies reported poor selection bias and data collection methods. Conclusions and Implications of Key Findings: The $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ may be predicted from RPE: $$ \dot{V}{\text{O}}_{2} $$ during PRET, especially when $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ is extrapolated to RPE during a second PRET. [ABSTRACT FROM AUTHOR]

Purpose: We assessed the validity of predicting peak oxygen uptake ( $$ {\dot{V}} $$ O peak) from the relationship between oxygen uptake ( $$ {\dot{V}} $$ O) and overall ratings of perceived exertion (RPE) obtained during the initial stages of a cardiopulmonary exercise test (CPET). Method: Fifteen healthy participants and 18 patients with chronic obstructive pulmonary disease (COPD) performed a maximal CPET, during which $$ {\dot{V}} $$ O and RPE were measured until RPE. Results: Individual regressions between $$ {\dot{V}} $$ O and RPE were extrapolated to RPE to predict $$ {\dot{V}} $$ O peak. Mean actual and predicted $$ {\dot{V}} $$ O peak were not significantly different in healthy women (18.9 ± 4.1 vs. 20.4 ± 4.5 mL kg min, respectively) and men (28.9 ± 7.8 vs. 29.7 ± 8.5 mL kg min, respectively), or in women (15.2 ± 4.7 vs. 15.8 ± 5.0 mL kg min, respectively) and men (16.2 ± 4.4 vs. 17.4 ± 5.4 mL kg min, respectively) with COPD ( P = 0.067). Moreover, actual and predicted $$ {\dot{V}} $$ O peak were highly correlated in healthy participants and COPD patients ( r ≥ 0.89; P < 0.001). The bias and 95 % limits of agreement were −1.0 ± 4.0 and −1.0 ± 4.6 mL kg min for healthy and COPD participants, respectively. Conclusion: $$ {\dot{V}} $$ O peak can be predicted with acceptable accuracy in healthy participants and patients with COPD from the individual relationship between $$ {\dot{V}} $$ O and RPE. [ABSTRACT FROM AUTHOR]

Purpose: Voluntary breath-holding (BH) elicits several hemodynamic changes, but little is known about maximal static immersed-body BH. We hypothesized that the diving reflex would be strengthened with body immersion and would spare more oxygen than maximal dry static BH, resulting in a longer BH duration. Methods: Eleven trained breath-hold divers (BHDs) performed a maximal dry-body BH and a maximal immersed-body BH. Cardiac output (CO), stroke volume (SV), heart rate (HR), left ventricular end-diastolic volume (LVEDV), contractility index (CTI), and ventricular ejection time (VET) were continuously recorded by bio-impedancemetry (PhysioFlow PF-05). Arterial oxygen saturation (SaO) was assessed with a finger probe oximeter. Results: In both conditions, BHDs presented a bi-phasic kinetic for CO and a tri-phasic kinetic for SV and HR. In the first phase of immersed-body BH and dry-body BH, results (mean ± SD) expressed as percentage changes from starting values showed decreased CO (55.9 ± 10.4 vs. 39.3 ± 16.8 %, respectively; p < 0.01 between conditions), due to drops in both SV (24.9 ± 16.2 vs. 9.0 ± 8.5 %, respectively; p < 0.05 between conditions) and HR (39.7 ± 16.7 vs. 33.6 ± 17.0 %, respectively; p < 0.01 between conditions). The second phase was marked by an overall stabilization of hemodynamic variables. In the third one, CO kept stabilizing due to increased SV (17.0 ± 20.2 vs. 10.9 ± 13.8 %, respectively; p < 0.05 between conditions) associated with a second HR drop (14.0 ± 10.0 vs. 12.7 ± 8.9 %, respectively; p < 0.01 between conditions). Conclusion: This study highlights similar time-course patterns for cardiodynamic variables during dry-body and immersed-body BH, although the phenomenon was more pronounced in the latter condition. [ABSTRACT FROM AUTHOR]

The nutritional status of elderly sportsmen has not been reported on, neither has the nutritional balance nor the precise relationship between nutritional status and physical fitness been detailed for this population. Thus, group of 18 sportsmen [age 63 (SD 4.5) years] was monitored by weighing their food during a 6-day period. Macro nutrient, mineral and vitamin content was derived from tables. Daily energy expenditure (DEE) and sport activity (DSA) were quantified over a 7-day period using a questionnaire. Physical fitness was assessed by maximal oxygen uptake ( V˙O2max) measurements. The DEE was 11 429 (SD 1890) kJ · day−1. The DSA corresponded to 38% of DEE and V˙O2max to 35.9 (SD 6.1) ml · min−1 · kg−1. When compared with French recommended dietary allowances (RDA) intakes were higher for energy (+24%), macro nutrients, and most minerals and vitamins. Despite high energy intakes, some subjects had mineral and vitamin deficits. Energy intakes were significantly related to intakes of magnesium, phosphorus, iron, vitamins B2, B6, C and to V˙O2max, but not to age. Stepwise regressions indicated that vitamin C intake was the only determinant to have a relationship with V˙O2max. Thus, most elderly sportsmen had higher nutritional status than RDA, although some had mineral and vitamin deficits. It is therefore suggested that elderly sportsmen should be encouraged to consume food with higher mineral and vitamin contents. [ABSTRACT FROM AUTHOR]

A response from the authors of the article "Submaximal, Perceptually Regulated Exercise Testing Predicts Maximal Oxygen Uptake: A Meta-Analysis Study" in the 2016 issue is presented.