Ethical Standards in Sport and Exercise Science Research: 2022 Update

Subjective and Objective Monitoring Markers: Are They Related to Game Performance Indicators in Elite Female Volleyball Players?

PURPOSE

This cohort study aimed to investigate the relationship between subjective (wellness and internal training load [ITL]) and objective (neuromuscular fatigue) monitoring markers and performance aspects (reception quality [RQ] and attack efficiency [AE]) in professional female volleyball players.

METHODS

The study was conducted over an 8-week period during the final mesocycle of the competitive phase. A total of 24 training sessions and 10 matches were included in the analysis. Subjective measures of wellness and ITL were assessed, and neuromuscular fatigue was evaluated using countermovement-jump (CMJ) height. RQ and AE were determined based on game statistics.

RESULTS

The study found a positive relationship between wellness and RQ, particularly affecting outside hitters and liberos. ITL showed a positive association with AE, primarily impacting outside hitters, opposite hitters, and middle blockers. Additionally, ITL demonstrated a negative correlation with RQ, mainly affecting outside hitters and liberos. CMJ performance was associated with AE, where a decrease in CMJ height was linked to reduced AE.

CONCLUSIONS

The findings highlight the importance of considering players' wellness scores in training and match strategies for different positions. Careful management of training loads, considering both physical and technical demands, is crucial for optimizing performance outcomes. Monitoring neuromuscular fatigue, as indicated by CMJ performance, is particularly relevant for outside hitters, opposite hitters, and middle blockers involved in attack actions. Coaches, trainers, and sports practitioners can use these insights to develop position-specific training protocols and implement effective strategies for maintaining or improving performance metrics under various stressors.

Influence of the Number of Players on the Load of Soccer Players During Transition Games

The aims of this study were to determine the effect of different compositions in transition games (TGs) on the load of soccer players and to evaluate their performance in physical tests. Using a GPS system, 18 players were monitored during: 3vs2, 2vs1 and 1vs1. Distance covered (DC), DC 18-20.9 km·h-1, 21-23.9 km·h-1,>24 km·h-1, peak speed, accelerations (Acc) and decelerations (Dec)>1.0 m·s-2 and>2.5 m·s-2 and rate of perceived exertion (RPE) were recorded. Before and after each TG, countermovement-jump (CMJ), 15- (S15) and 30 m (S30) speed tests were assessed. TG3vs2 showed greater DC and Dec>1.0 m·s-2 than TG2vs1, and DC, DC 18.0-23.9 km·h-1, Acc>1.0 m·s-2 and Dec>2.5 m·s-2 than TG1vs1 (p<0.01). TG2vs1 achieved higher DC, DC 18.0-23.9 km·h-1, and Acc>2.5 m·s-2 (p<0.01) but lower peak speed (p=0.02) and RPE (p=0.02) than TG1vs1. Post-intervention, TG1vs1 showed lower CMJ and higher S15 (p=0.02), while TG3vs2, showed improvements in CMJ (p<0.01). The three tasks showed large variations for DC>24 km·h-1, Acc>1.0 m·s-2, Dec>1.0 m·s-2 and Dec>2.5 m·s-2. The load of TGs is sensitive to their player composition.

Tirzepatide and exercise training in obesity

OBJECTIVES

The purpose of this study was to investigate the effects of 6 weeks of resistance training (RT) combined with aerobic training (AT) and Tirzepatide supplementation on lipid profiles, insulin resistance, anthropometric characteristics and physical fitness in prediabetic obese soldiers.

METHODS

61 obese men were randomly divided into six groups: Placebo; Tirzepatide 5 mg (T5); Tirzepatide 2.5 mg (T2.5); Hypertrophy, Strength, Power-Circuit Training+Placebo (Ex+P); Hypertrophy, Strength, Power-Circuit Training+Tirzepatide 5 mg (Ex+T5); Hypertrophy, Strength, Power-Circuit Training+Tirzepatide 2.5 mg (Ex+T2.5). All training groups performed aerobic training (AT) after resistance training. Subjects trained for six weeks, three sessions per week. Before and after the intervention period, the participants were evaluated for anthropometric measures, body composition [body weight, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and fat mass (FM)], cardiorespiratory fitness (VO2max), and muscle strength (chest press 1RM and leg press 1RM). Blood biochemistry evaluations included triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), insulin level and insulin resistance (HOMA-IR). To evaluate the differences between the groups, ANCOVA statistical method was used along with Bonferroni's post hoc test, and the significance level was P <  0.05.

RESULTS

Body weight, BMI, WC, FM, FBG, LDL-C, TC, TG and HOMA-IR were significantly decreased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo, T5 and T2.5 groups. WHR significantly decreased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo group. HDL-C, chest press and leg press significantly increased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo, T5 and T2.5 groups. VO2max significantly increased and insulin significantly decreased in Ex+P group compared to Placebo, T5 and T2.5 groups. FM, FBG and TG were significantly decreased in both the T2.5 and T5 groups compared to Placebo group. HOMA-IR, LDL-C and TC significantly decreased in the T5 group compared to Placebo group. Also, leg press significantly increased in Ex+P group compared to all other groups.

CONCLUSIONS

Performing six weeks of combined resistance and aerobic training in the form of RT+AT alone is more effective than the simultaneous use of Tirzepatide on cardiorespiratory fitness, strength, and modulating insulin levels. Taking Tirzepatide in doses of 5 mg and 2.5 mg in combination with exercise training did not have a significant advantage over exercise training alone. Finally, taking Tirzepatide in doses of 5 mg or 2.5 mg in combination with exercise training is not significantly superior to each other.

Athletic retirement: factors contributing to sleep and mental health problems

Introduction

The aim of this investigation was to determine which factors were associated with symptoms of sleep and mental health disorders in former athletes.

Methods

Former athletes (N = 173, 50% women) who retired from any competition level within the last 20 years participated in an online survey. The survey consisted of the Athlete Sleep Screening Questionnaire (ASSQ), Personal Wellbeing Index-Adult (PWI-A), Center for Epidemiologic Studies Depression Scale-Revised (CESD-R), and Generalised Anxiety Disorder Assessment (GAD-7).

Results

Binary logistic regressions revealed that both age (OR = 0.95 [95% CI:0.92, 0.99], p = 0.007) and gender (OR = 2.28 [95% CI:1.09, 4.79], p = 0.029) were associated with anxiety, with women and younger ex-athletes presenting greater risk of anxiety symptoms. Higher body mass was associated with an increased risk for sleep difficulty (OR = 1.13 [95% CI:1.03, 1.23], p = 0.008), sleep disordered breathing (OR = 1.20 [95% CI:1.10, 1.30], p < 0.001), and compromised wellbeing (OR = 0.89 [95% CI:0.83, 0.96], p = 0.001). Athletes who subjectively placed a lower priority on sport while competing presented greater risk of sleep disordered breathing (OR = 2.00[95% CI:1.05, 3.80], p = 0.035). No associations between recency retirement and any outcome measures were observed.

Discussion

Findings suggest potential predictive factors for difficulty transitioning out of sport. Future longitudinal research should consider the interplay between sport re-engagement and the incidence and chronicity of sleep and mental health disorders.

Impact of Strength Training Intensity on Brain-derived Neurotrophic Factor

The present study employed a randomized crossover design to investigate the effect of strength-training exercise at varying intensities on acute changes in plasma brain-derived neurotrophic factor (BDNF) levels. Fourteen trained male subjects (41.0±5.8 years old) were enrolled in the current study. The strength-training protocol included bench press, leg press, and lat pull-down exercises. Participants performed four sets with repetition failure at 60% or 80% of their one-repetition maximum (1RM), with a two-minute rest period. The order of intensity was randomized among volunteers. Blood samples were collected before, immediately after, and one hour after each exercise protocol. A time-point comparison revealed that a single session of strength training at 60% of 1RM increased lactate plasma concentrations from 1.2 to 16 mmol/L (p<0.0001). However, no significant changes were observed in the plasma BDNF concentration. Conversely, the training session at 80% of 1RM increased lactate concentrations from 1.3 to 14 mmol/L (p<0.0001) and BDNF concentrations from 461 to 1730 pg/ml (p=0.035) one hour after the session's conclusion. These findings support the hypothesis that a single strength-training session at 80% 1RM can significantly enhance circulating levels of BDNF.

Effects of acute aerobic exercise on arterial stiffness in transgender men

Testosterone replacement therapy (TRT) in transgender men (TM) results in side effects such as elevated triglycerides and increased arterial stiffness. Exercise may be useful to ameliorate such effects, but no studies have examined the effects of acute aerobic exercise in TM. This study aimed to investigate the effects of acute aerobic exercise on arterial stiffness in TM. Thirty-six participants were included, comprising 12 TM (duration of TRT: 57.4 ± 30.3 months), 12 males and 12 females. All participants performed acute aerobic exercise on a treadmill at 50% heart rate reserve for 30 min. Arterial stiffness as measured by brachial-ankle pulse wave velocity (baPWV) was measured before exercise (Pre), 30 min after exercise (Post30), and 60 min after exercise (Post60). Serum sex hormone levels, and serum lipid profile were determined only before exercise. Serum low-density lipoprotein cholesterol (LDL-C) levels before exercise were significantly higher in TM than in males or females (males: p < 0.01; females: p < 0.05). At all points, baPWV in TM was significantly higher than in females (p < 0.05) and significantly lower than in males (p < 0.05). However, when comparing changes in baPWV over time in each group, significant decreases in Post30 and Post60 were seen in males compared to Pre (both p < 0.05), but no significant change after aerobic exercise was seen in TM or females. These results suggest that acute aerobic exercise yield different effects in TM than in males, but is unlikely to reduce arterial stiffness in TM receiving TRT.

Positional Differences in Muscle-to-bone Ratio in National Football League Players

The purpose of the present study was to examine the muscle-to-bone ratio (MBR) in National Football League (NFL) players. Three hundred and forty-six NFL players had their total body lean, fat and bone masses determined using dual X-ray absorptiometry and were compared to 228 age-matched, healthy male controls. Compared to the control group, NFL players had a significantly lower percent total body fat (17.90±6.92 vs. 22.93±8.96%, p=0.053), but significantly greater total fat mass (19.76±11.29 vs. 17.84±12.11 kg, p<0.0001), lean mass (84.55±8.75 vs. 55.3±11.79 kg, p<0.0001), bone mineral content (4.58±0.45 vs. 2.91±0.67 kg, p<0.0001), and bone mineral density (1.61±0.11 vs. 1.26±0.21 g/cm2, p<0.0001). NFL players had greater arm MBR (17.70±1.47 vs. 16.48±1.88, p<0.0001) than controls; however, both trunk (26.62±2.55 vs. 31.56±4.19, p<0.0001) and total (18.50±1.31 vs. 19.12±1.88, p<0.001) MBR were lower in NFL players. Leg MBR was not significantly different between NFL players and controls (16.72±1.53 vs. 16.85±1.87, p=0.34). When NFL players were categorized by their offensive or defensive position for comparison, no differences in total MBR were observed. However, leg MBR varied greatly among NFL players by position. It is possible that regional differences in MBR in the NFL players may be related to the demands of that position.

Determinants of Dual-task Gait Speed in Older Adults with and without Parkinson's Disease

Mobility difficulties for people with Parkinson's disease (PwPD) are more pronounced when they perform a simultaneous cognitive task while walking. Although it is known that neurodegeneration results in widespread motor and brain impairments, few studies have comprehensively examined possible physical and mental determinants of dual task walking in PwPD. In this cross-sectional study, we aimed to investigate if and how muscle strength (sit-to-stand 30-sec test), cognition (mini-mental state examination) and functionality (timed up and go test) affect walking performance (10-meter walking test) with and without arithmetic dual task from older adults with and without Parkinson's disease. Walking speed was reduced by 16% and 11% with arithmetic dual task for PwPD (from 1.07±0.28 to 0.91±0.29 m.s-1, p<0.001) and older adults (from 1.32±0.28 to 1.16±0.26 m.s-1, p=0.002) compared to essential walking. The cognitive state was similar among the groups, but it was only associated with the dual-task walking speed in PwPD. In PwPD, lower limb strength was the better predictor of speed, whereas mobility was more related to it in older adults. Therefore, future exercise interventions aiming to improve walking in PwPD should consider these findings to maximize their effectiveness.

Effects of Exercise Intensity on Cardiometabolic Parameters of Ovariectomized Obese Mice

The aim of this study was to compare the effects of continuous-moderate vs. high-intensity interval aerobic training on cardiovascular and metabolic parameters in ovariectomized high-fat-fed mice. C57BL/6 female ovariectomized were divided into four groups (n=8): low-fat-fed sedentary (SLF); high-fat-fed sedentary (SHF); high-fat-fed moderate-intensity continuous trained (MICT-HF); and high-fat-fed high-intensity interval aerobic trained (HIIT-HF). The high-fat diet lasted 10 weeks. Ovariectomy was performed in the fourth week. The exercise training was carried out in the last four weeks of protocol. Fasting glycemia, oral glucose tolerance, arterial pressure, baroreflex sensitivity, and cardiovascular autonomic modulation were evaluated. Moderate-intensity continuous training prevented the increase in arterial pressure and promoted a reduction in HR at rest, associated with an improvement in the sympathovagal balance in MICT-HF vs. SHF. The high-intensity interval training reduced blood glucose and glucose intolerance in HIIT-HF vs. SHF and MICT-HF. In addition, it improved sympathovagal balance in HIIT-HF vs. SHF. Moderate-intensity continuous training was more effective in promoting cardiovascular benefits, while high-intensity interval training was more effective in promoting metabolic benefits.

Total and Regional Body Composition of NCAA Collegiate Female Rowing Athletes

This study explored body composition in female NCAA Division I rowers compared to controls; and the effect of season, boat category, and oar side on body composition. This retrospective analysis of 91 rowers, and 173 age, sex, and BMI-matched controls examined total and regional fat mass (FM), lean mass (LM), bone mineral content (BMC), bone mineral density (BMD), percent body fat (%BF), and visceral adipose tissue (VAT) measured using dual X-ray absorptiometry. Two-sample t-testing was used to assess differences between rowers and controls. Repeated measures ANOVA analyzed differences across seasons. ANOVA analyzed differences between boat categories. Paired t-testing analyzed oar side versus non-oar side. Rowers had greater height (174.2; 164.1 cm), weight (75.2; 62.6 kg), LM (51.97; 41.12 kg), FM (20.74; 19.34 kg), BMC (2.82; 2.37 kg), and BMD (1.24; 1.14 g/cm²); but lower %BF (30.5%; 27.1%), and VAT (168.1; 105.0 g) than controls (p<0.05). Total, arm, and trunk muscle-to-bone ratio were greater in rowers (p<0.001). Rowers demonstrated greater arm LM (5.8 kg; 5.6 kg) and BMC (0.37 kg; 0.36 kg) in Spring compared to Fall (p<0.05). 1V8 rowers had a lower %BF than non-scoring rowers (25.7%; 29.0%; p=0.025). No differences observed between oar sides. These findings will help rowing personnel better understand body composition of female collegiate rowers.

Effects of Training and Taper on Neuromuscular Fatigue Profile on 100-m Swimming Performance

This study aimed to investigate the effects of 6-week specific preparatory period and 2-week taper period on neuromuscular fatigue profile in 100-m front crawl swimming performance. Seventeen competitive-level young-adult swimmers performed a 100-m swimming performance at baseline and after 6-week specific preparatory followed by 2-week taper periods. Neuromuscular fatigue profile was assessed through percutaneous electrical stimuli on the femoral nerve during a maximal voluntary contraction performed before and immediately after each 100-m maximal effort. Performance improved (p=0.001) 2.24 and 3.06% after specific and taper, respectively. Potentiated peak force at post-effort condition decreased (p<0.001) 16.26% at baseline, 11.70% at specific, and 12.86% at taper period. Maximal voluntary contraction force also decreased (p<0.001) at post-effort condition by about 6.77 and 9.33% at baseline and specific period, respectively. Both variables did not present significant differences between times. No condition or time effects were observed to superimposed peak force and voluntary activation, both related to central fatigue. In conclusion, neuromuscular fatigue during 100-m swimming performance was exclusively developed by peripheral mechanisms regardless of the training period, and 2-week taper was able to prevent decreases in maximal voluntary contraction induced by 100-m maximal effort.

Prediction of Marathon Performance using Artificial Intelligence

Although studies used machine learning algorithms to predict performances in sports activities, none, to the best of our knowledge, have used and validated two artificial intelligence techniques: artificial neural network (ANN) and k-nearest neighbor (KNN) in the running discipline of marathon and compared the accuracy or precision of the predicted performances. Official French rankings for the 10-km road and marathon events in 2019 were scrutinized over a dataset of 820 athletes (aged 21, having run 10 km and a marathon in the same year that was run slower, etc.). For the KNN and ANN the same inputs (10-km race time, body mass index, age and sex) were used to solve a linear regression problem to estimate the marathon race time. No difference was found between the actual and predicted marathon performances for either method (p>0,05). All predicted performances were significantly correlated with the actual ones, with very high correlation coefficients (r>0,90; p<0,001). KNN outperformed ANN with a mean absolute error of 2,4 vs 5,6%. The study confirms the validity of both algorithms, with better accuracy for KNN in predicting marathon performance. Consequently, the predictions from these artificial intelligence methods may be used in training programs and competitions.

Stakeholders' Consensus to Guide the Minimum Impairment Criteria in Wheelchair Basketball

The International Paralympic Committee athlete classification code mandates sports to have defined minimum impairment criteria, describing the minimum level of an eligible impairment an athlete must possess, to be able to participate in that sport. The aim of this study was to establish stakeholders' consensus for the minimum impairment criteria in wheelchair basketball. From a pool of 48 expert stakeholders (identified via an international medical and scientific working group), 39 completed a 4-round Delphi survey. Questions were answered on the method of assessing each eligible impairment, and the level of impairment that should constitute the minimum impairment criteria. This study indicated where stakeholder consensus existed and noted that consensus was developed for impaired muscle power, impaired passive range of motion, leg length difference, hypertonia and ataxia. No consensus was found for limb deficiency and athetosis. Participants raised concerns with using subjective measurement scales for assessing certain impairments, whilst also calling for more quantitative research to be conducted into the level of impairment that should constitute the minimum impairment criteria. For these research findings to form practical minimum impairment criteria that are part of a wheelchair basketball classification system, it is required to examine their feasibility by conducting further research.

Peak Height Velocity Affects Injury Burden in Circa-PHV Soccer Players

Growth and maturation are potential risk factors for soccer injuries. This research sought to describe how peak height velocity (PHV) affects overall and specific injury burden in circa- and post-PHV elite academy soccer players. Injuries and growth data collected from 2000 to 2020 were studied retrospectively. Longitudinal height records for 124 players were fitted with the Super-Imposition by Translation and Rotation model to calculate PHV (cm/year) and age at PHV. Players were classified according to PHV percentile (fast:≥75th; average: 25-75th; slow:≤25th) and maturity status (circa- or post-PHV). Overall and specific injury burden (days lost/player-season) and rate ratios for comparisons between groups were calculated based on zero-inflated negative binomial models. Confidence intervals were calculated at the 95% confidence level (CI) and the significance level was set at<0.05. In circa-PHV, players with fast PHV had 2.6 (CI: 1.4-4.8)- and 3.3 (CI:1.3-6.7)-times higher overall burden and 2.9 (CI:1.1-7.1)- and 4.1 (CI: 1.4-15.2)-times higher for growth-related injury burden compared to players with average and slow PHV, respectively. Regular monitoring of growth seems important to detect players at higher risk for being disrupted by growth-related injuries.