Physical Performance Variables Research Articles

The relationship between ambient temperature and match running performance of elite soccer players.

The influence of environmental factors on key physical parameters of soccer players during competitive match-play have been widely investigated in the literature, although little is known on the effects of sub-zero ambient temperatures on the performance of adult elite soccer players during competitive matches. The aim of this study was to assess how the teams' match running performance indicators are related to low ambient temperature during competitive matches in the Russian Premier League. A total of 1142 matches played during the 2016/2017 to 2020/2021 seasons were examined. Linear mixed models were used to assess the relationships between changes in ambient temperature at the start of the match and changes in selected team physical performance variables, including total, running (4.0 to 5.5 m/s), high-speed running (5.5 to 7.0 m/s) and sprint (> 7.0 m/s) distances covered. The total, running and high-speed running distances showed no significant differences across temperatures up to 10°C, while these showed small to large decreases at 11 to 20°C and especially in the >20°C ranges. On the contrary, sprint distance was significantly lower at temperature of -5°C or less compared to higher temperature ranges. At sub-zero temperatures, every 1°C lower reduced team sprint distance by 19.2 m (about 1.6%). The present findings show that a low ambient temperature is negatively related to physical match performance behavior of elite soccer players, notably associated with a reduced total sprint distance.

Physical-Performance Changes Over the Season: Are They Related to Game-Performance Indicators in Elite Men Volleyball Players?

The development and influence of physical capabilities and game action performance over the course of the season are a big challenge for coaches and players. The aims of the present study were to examine (1)the seasonal changes in the physical capabilities (mechanical and kinematic) and game-performance indicators in top-level men volleyball players and (2)the relationship between these physical capabilities and game-performance indicators in official matches. Eleven top-level players participated. Players were physically tested 3 times during the season. Before each test, players' match performance (11 sets) was analyzed according to the level of opposition and match location. The percentage of change, statistical differences over the season (Friedman and Wilcoxon tests), and associations between variables (Spearman r) were calculated (P < .05) among mechanical (force-velocity profile during vertical jump and bench press), kinematic (jump height and spike ball speed), and game action performance features (coefficient, efficacy, and percentage of errors in serve, attack, and block). The theoretical maximal force and velocity during vertical jump and bench press, respectively; the peak spike ball speed; and the serve efficacy significantly increased over the season. Moreover, there was a significant reduction in serve errors as the jump height increased (r = -.44; P = .026), as well as a significant increase in serve errors as the peak spike ball speed increased (r = -.62; P = .001). These findings reveal how the physical and game action performance variables evolve and interact during the season. This may help coaches and trainers to monitor and analyze the most relevant volleyball performance factors.

Mortality, falls and slow walking speed are predicted by different muscle strength and physical performance measures in women and men

BackgroundDifferent measures of muscle strength, physical performance and body size/composition are used in various sarcopenia definitions. This study investigated which baseline measures best predict incident mortality and falls, and prevalent slow walking speed in older women and men. Materials and methodsData for 899 women (mean age±standard deviation, 68.7 ± 4.3 years) and 497 men (69.4 ± 3.9 years) from the Dubbo Osteoporosis Epidemiology Study 2, comprising sixty variables for muscle strength (quadriceps strength), physical performance (walking speed, timed up and go (TUG) test, sit to stand (STS) test), body size (weight, height, body mass index) and body composition (lean mass, body fat) were included. Sex-stratified Classification and Regression Tree (CART) analyses calculated baseline variable accuracy for predicting incident mortality and falls, and prevalent slow walking speed (<0.8 m/s). ResultsOver 14.5 years, 103/899 (11.5%) women and 96/497 (19.3%) men died, 345/899 (38.4%) women and 172/497 (34.6%) men had ≥1 fall, and 304/860 (35.3%) women and 172/461 (31.7%) had baseline slow walking speed (<0.8 m/s). CART models identified age and walking speed adjusted for height as the most important predictors for mortality in women, and quadriceps strength (with adjustments) as the most important predictor for mortality in men. In both sexes, STS (with adjustments) was the most important predictor for incident falls, and TUG test was the most important predictor for prevalent slow walking speed. Body composition measures were not important predictors for any outcome. ConclusionsMuscle strength and physical performance variables and cut points predict falls and mortality differently in women and men, suggesting targeted sex-specific application of selected measures may improve outcome prediction in older adults.

Changes in Sprint Force–Velocity Profile in International Para Footballers

Force production is crucial in football, and it is the main limitation of people with cerebral palsy (CP). This study aimed to describe the changes in sprint force-velocity (Fv) profile after a period of 25weeks of regular training in international football players with CP. The sprint Fv profile and other physical performance variables (ie,linear sprint, vertical jump, change of direction, and intermittent endurance) of 14 international players from the Spanish national team were assessed during 2 consecutive training camps. Pretesting and posttesting sessions were carried out 1week before and after the 25-week intervention period. The intervention consisted of 2 strength sessions per week added to the usual football training. The repeated-measures analysis of variance showed changes in players' physical performance (linear sprint: F = 18.05, P < .01; change of direction: F = 16.71, P < .01; and endurance: F = 31.45, P < .01) and in some variables of the sprint Fv profile (maximal horizontal force, maximal power, slope, maximal ratio of force, and decrease of ratio of force; F = 14.28-37.81; P < .01), whereas players' maximal velocity (theoretical and actual) did not change (F = 0.13 and 0.01; P = .72 and .98, respectively). This study showed that the implementation of 2 strength-training sessions per week, for 25weeks, is effective to improve CP football players' physical performance. The main finding of this study is the improvement of force application in the acceleration phase (sprint Fv profile), which is the main attribute in many physical performance tests and is the main limitation of the CP population.

Physiological and physical performance changes during a 20-day winter military training course and its subsequent 10-day recovery period

ABSTRACT The present study investigated physiological, mental and physical performance changes during a 20-day winter military training course and the following 10-day recovery period. Fifty-eight (age 19 ± 1 years, height 182 ± 6 cm, body mass 78.5 ± 7.2 kg) male soldiers volunteered. Body composition, serum biomarker levels and performance tests were measured four times during the study. In addition, questionnaires were collected daily for subjective stress and rate of perceived exertion. The course induced significant declines in body (−3.9%, p < 0.05) and fat mass (−31.6%, p < 0.05) as well as in all assessed physical performance variables (−9.2 - −20.2%, p < 0.05), testosterone (−73.7%, p < 0.001) and IGF-1 concentrations (−43.6%, p < 0.001). At the same time, the sex hormone-binding globulin, creatine kinase, and C-reactive protein values increased significantly (46.3–1952.7%, p < 0.05). After the 10-day recovery period, the body composition and hormonal values returned to the baseline (p < 0.05), as did some physical performance variables, such as 2 min sit-ups and the evacuation test (p < 0.05). However, explosive force production in the upper and lower bodies remained unrecovered. The 20-day winter military training caused significant physiological and mental stress, as well as a drastic decline in physical performance even for highly physically fit soldiers, and the 10-day recovery period did not establish full recovery.

Effects of Neuromuscular Training on Physical Performance in Older People: A Systematic Review.

This systematic review aimed to assess the available evidence on the effects of neuromuscular training on physical performance in older adults. A literature search was conducted across four databases (Psychology and Behavioral (EBSCO), Scopus, Web of Science and PubMed). The PRISMA guidelines were followed. The PEDro scale and Cochrane risk of bias tool were used to assess the quality of and risk of bias in the studies, respectively. The protocol was registered in PROSPERO (code: CRD42022319239). The outcomes were muscle strength, cardiorespiratory fitness, postural balance and gait speed. From 610 records initially found, 10 were finally included in the systematic review, involving 354 older people with a mean age of 67.3 years. Nine of them reported significant changes in at least one variable related to physical performance in the intervention compared to the control groups. The neuromuscular training caused significant improvements in postural balance, flexibility, cardiorespiratory fitness, strength power of the upper and lower limbs and autonomy. The available evidence indicates that neuromuscular training has a positive effect on some variables of physical performance, especially in postural balance; however, the methodological quality and certainty of the evidence in the available literature are limited. Therefore, a greater number of high-quality studies are required to draw definitive conclusions.

Energy Balance, Hormonal Status, and Military Performance in Strenuous Winter Training

Severe energy deficit may impair hormonal regulation and physical performance in military trainings. The aim of this study was to examine the associations between energy intake, expenditure, and balance, hormones and military performance during a winter survival training. Two groups were studied: the FEX group (n = 46) had 8-day garrison and field training, whereas the RECO group (n = 26) had a 36-h recovery period after the 6-day garrison and field training phase. Energy intake was assessed by food diaries, expenditure via heart rate variability, body composition by bioimpedance, and hormones by blood samples. Strength, endurance and shooting tests were done for evaluating military performance. PRE 0 d, MID 6 d, POST 8 d measurements were carried out. Energy balance was negative in PRE and MID (FEX -1070 ± 866, -4323 ± 1515; RECO -1427 ± 1200, -4635 ± 1742 kcal·d-1). In POST, energy balance differed between the groups (FEX -4222 ± 1815; RECO -608 ± 1107 kcal·d-1 (p < 0.001)), as well as leptin, testosterone/cortisol ratio, and endurance performance (p = 0.003, p < 0.001, p = 0.003, respectively). Changes in energy intake and expenditure were partially associated with changes in leptin and the testosterone/cortisol ratio, but not with physical performance variables. The 36-h recovery restored energy balance and hormonal status after strenuous military training, but these outcomes were not associated with strength or shooting performance.

When and How Do Soccer Players From a Semi-Professional Club Sprint in Match Play?

The aims of this study were to investigate the periods in which sprints occurred during official matches and analyze these sprints considering the effect of the playing position and different contextual variables. Electronic performance and tracking systems were used for the analysis of all sprints performed by players. Matches were recorded by video and synchronized with performance tracking data. A total of 252 sprints were analyzed. The greatest frequency of sprints was observed in the period 1 (0'-15'), followed by period 2 (15'-30') and period 6 (75'-90'), regardless of the playing position (χ2 = 31.35; p = 0.051). Most sprints were non-linear (non-linear sprints: 97.6%; linear sprints: 2.4%) and without ball possession (without ball possession: 95.2%; with ball possession: 4.8%) for all playing positions, but the role of the sprint and the field area in which the sprint occurred were dependent on the position (p < 0.001). Specifically, players covered ~17.55 m per sprint, starting at ~10.34 km/h, reaching ~26.74 km/h, maximally accelerating at ~2.73 m/s2, and decelerating at ~3.61 m/s2. Overall, the playing position and contextual variables had no significant effect on physical performance variables analyzed during these sprints. Therefore, this study allows performance practitioners to have a better understanding of when and how soccer players sprint in match-play. In this regard, this study presents some training and testing strategies that may be considered to improve performance and decrease injury risk.

Effect of Increasing the Number of Substitutions on Physical Performance during Periods of Congested Fixtures in Football

(I) This study aimed to evaluate the impact on physical demands induced by FIFA's new rule implemented based on the number of substitutions caused by COVID-19. (II) Sixty-six matches were analysed in peak periods (microcycles of three matches in a week) in the competition period before and after the pandemic. The variables collected were organised by team (22 from LaLigaTM SmartBank 2019-2020) for a total of 132 team records and 1077 player performance reports using a multi-camera tracking system and Mediacoach® software. Physical performance variables were analysed in the first half, second half and whole match, thus determining the individual and collective performances of the team. (III) This study shows how, despite the increase in substitutions allowed with the new rule, physical performance increased in some variables in the congested periods (e.g., total distance run and distance run in the first and second halves). Additionally, the players' physical performance involved in a substitution was greater than it was for players who completed the game. (IV) The new substitution rule helps to maintain and even improve physical performance. This measure could improve intensity levels in both individual and team performance. It could even safeguard the physical integrity of the players by reducing the risk of injury, as fewer players have to play the full match.

Association between PhA and Physical Performance Variables in Cancer Patients.

Maintaining the physical performance of cancer patients is increasingly considered due to the growing number of cancer patients and the aggressiveness of the treatments. For this reason, bioimpedance is now being used to record patients' body composition by obtaining the phase angle (PhA). Although there is a direct relationship between PhA, age, sex and disease prognosis, it has not been measured as an analysis of physical performance in oncology patients and is a valid tool in the follow-up of cancer patients. For this purpose, 311 patients were evaluated, and both bioelectrical impedance analysis (BIA) and physical performance measurements were performed. The modification of the results concerning PhA was found to be highly relational, as a variation in one of the variables affected the other. It was concluded that each degree increase in PhA modified -22.57 s [-27.58; -17.53] in 400-m walking test (400 mWT); 13.25 kg [10.13; 16.35] in upper-body strength (UBS); 6.3 [4.95; 7.65] in lower-body strength (LBS); 1.55 mL/kg/min [0.98; 2.12] in VO2peak; 6.53 Watts [3.83; 9.20] in ventilatory threshold 1 (VT1); 10.36 Watts [7.02; 13.64] in ventilatory threshold 2 (VT2). It was also noted that age was a factor that affected the relationship between PhA and 400 mWT; the older the age, the higher the relationship. PhA data has been shown to be highly correlated with physical performance. This is of great importance in clinical practice because a cancer patient's physical performance levels can be assessed during treatment.

Systemic Inflammation but not Oxidative Stress Is Associated with Physical Performance in Moderate Chronic Obstructive Pulmonary Disease.

Chronic obstructive pulmonary disease (COPD) patients manifest muscle dysfunction and impaired muscle oxidative capacity, which result in reduced exercise capacity and poor health status. The aim of this study was to compare the physical performance, systemic inflammation, and oxidative stress of patients with moderate COPD, and to associate physical performance with inflammatory and oxidative stress plasma markers. Twenty CONTROL (n=10) and moderate COPD (n=10) patients participated in this study. Systematic inflammation and oxidative stress plasma markers, maximal aerobic capacity (VO2peak), and maximal isometric strength (MVIC) of the knee extensor (KE) muscles were measured. VO2peak was 31.3% greater in CONTROL compared to COPD (P=0.006). The MVIC strength of the KE was 43.9% greater in CONTROL compared to COPD (P=0.002). Tumor necrosis factor-alpha (TNF-α) was 79.6% greater in COPD compared to CONTROL (P<0.001). Glutathione peroxidase activity (GPx) activity was 27.5% lesser in COPD compared to CONTROL (P=0.05). TNF-α concentration was correlated with KE MVC strength (R=-0.48; P=0.045) and VO2peak (R=-0.58; P=0.01). Meanwhile, malondialdehyde (MDA) and GPx activity were not associated with KE strength or VO2peak (P=0.74 and P=0.14, respectively). COPD patients showed lesser muscle strength and aerobic capacity than healthy control individuals. Furthermore, patients with COPD showed greater systemic inflammation and lesser antioxidant capacity than healthy counterparts. A moderate association was evident between levels of systemic inflammation and physical performance variables.

Comparisons and correlations between the anthropometric profile and physical performance of professional female and male soccer players: Individualities that should be considered in training

For male soccer players, the anthropometric profile and physical performance is already known but in women it is not well documented, the knowledge of these differences can qualify the training. Therefore, the aim of this study was two-fold: (i) to compare the anthropometric profile and physical fitness of Brazilian professional female and male soccer players; and (ii) analyze the relationships between anthropometric and physical fitness measures per sex. A cross-sectional study including 92 professional soccer players 44 women and 48 men was conducted. After one week of the end of the pre-season, the players from four different teams were assessed to anthropometric profile assessments and physical performance tests (e.g., jumping, linear sprint, change-of-direction and aerobic based test). Comparisons, correlation, and effect size analysis were performed between groups. Apart from the age and change-of-direction test, all other anthropometric and physical performance variables were significant different between women and men. Men were significantly faster than women in the 20 m linear sprint test (8.87%; p &lt; .001; d = 2.382). The sum of skinfolds was correlated with some physical performance variables; however, body mass and body height were corrected with physical performance only for female soccer players. Thus, men performed better than women for most physical tests and presents differences in the anthropometric profile. Finally, coaches should consider that the anthropometric and performance profile are correlated differently between female and male soccer players. Thus, coaches should consider gender-specific parameters to create goals about the anthropometric and physical performance profile of players.

The Physical Demands of Match-Play in Academy and Senior Soccer Players from the Scottish Premiership.

The present study aimed to assess the physical match performance among senior and youth soccer players from an elite Scottish Premiership club during the 2021/2022 season. Twenty-two first team (25.9 ± 4.5 years, 78.3 ± 8.2 kg, 1.82 ± 0.07 cm) and 16 youth players (16.8 ± 0.9 years, 70.1 ± 6.8 kg, 177 ± 5.8 cm) were examined. A selection of physical match performance variables were measured using a global positioning system. Linear mixed-effect regressions revealed for all examined variables no significant differences between first team and U-18 players and no significant differences between playing level by position interaction. Across both teams, Centre Backs compared to Wing Backs, showed a 295 m (p < 0.01) lower high-intensity distance, and performed on average 36 fewer very-high intensity decelerations (p = 0.03). Comparing to Wide Midfielders, Centre Backs showed lower total (1297 m, p = 0.01), high-intensity (350 m, p = 0.01), and sprint (167 m, p < 0.01) distances. Sprint distance was also lower in Centre Backs vs. Strikers (118 m, p = 0.03), and in Central Midfielders vs. both Strikers (104 m, p = 0.03) and Wide Midfielders (154 m, p = 0.01). The present findings highlight the physical match performance of elite Scottish players and provide useful information within the context of understanding how methods of physical development of youth soccer are implemented in different countries.

Predictive models for musculoskeletal injury risk: why statistical approach makes all the difference

ObjectiveCompare performance between an injury prediction model categorising predictors and one that did not and compare a selection of predictors based on univariate significance versus assessing non-linear relationships.MethodsValidation and replication...

Self-Organizing Maps to Multidimensionally Characterize Physical Profiles in Older Adults.

The aim of this study is to automatically analyze, characterize and classify physical performance and body composition data of a cohort of Mexican community-dwelling older adults. Self-organizing maps (SOM) were used to identify similar profiles in 562 older adults living in Mexico City that participated in this study. Data regarding demographics, geriatric syndromes, comorbidities, physical performance, and body composition were obtained. The sample was divided by sex, and the multidimensional analysis included age, gait speed over height, grip strength over body mass index, one-legged stance, lean appendicular mass percentage, and fat percentage. Using the SOM neural network, seven profile types for older men and women were identified. This analysis provided maps depicting a set of clusters qualitatively characterizing groups of older adults that share similar profiles of body composition and physical performance. The SOM neural network proved to be a useful tool for analyzing multidimensional health care data and facilitating its interpretability. It provided a visual representation of the non-linear relationship between physical performance and body composition variables, as well as the identification of seven characteristic profiles in this cohort.

Elite Rugby Players have Unique Morphological Characteristics of the Hamstrings and Quadriceps Femoris Muscles According to their Playing Positions.

Rugby is a popular sport requiring high-intensity and maximal speed actions. Numerous studies have demonstrated that physical performance variables, such as strength, sprinting, and jumping, are different between the forwards and backs. However, there is little information about muscle morphological characteristics specific for each rugby playing position. This study aimed to clarify the morphological characteristics of the thigh muscles in forwards and backs. Ultrasound images were obtained from the proximal, middle, and distal regions of the thigh. Then, the anatomical cross-sectional areas of particular muscles in the hamstrings and quadriceps femoris were calculated for seven forwards, seven backs, and ten non-athletes. The anatomical cross-sectional areas were normalised by the two-third power of lean body mass, and the normalised values of the three regions were averaged as that of the individual muscle. In the hamstrings, the normalised anatomical cross-sectional areas of the biceps femoris long head were significantly greater in forwards than in non-athletes, whereas those of the semitendinosus were significantly greater in backs than in non-athletes. Furthermore, in the quadriceps femoris, the normalised anatomical cross-sectional areas of the rectus femoris and vastus intermedius were significantly greater in forwards than in backs and non-athletes. These results suggest that forwards have great muscularity of the biceps femoris long head and vastus intermedius which can generate large force, whereas backs possess great muscularity of the semitendinosus which can generate high contraction velocity. These findings allow coaches to design more effective training programs according to particular rugby playing positions.

Effects of Carbohydrate and Sodium Chloride Mouth Rinses on Repeated Sprint Performance

Aim: The purpose of this research is to examine the effects of oral rinsing of CHO and NaCl on repeated sprint performance in trained athletes.&#x0D; Methods: Fifteen trained athletes (5 women; 10 men) voluntarily participated in the repeated, single-blind, placebo-controlled and crossover design study. Athletes came to the laboratory with a night fasting four times with an interval of at least 48 hours and participated in the repeated sprint test (10 sec × 6, 40 sec intervals) after 30 minutes of endurance exercise (70% maxVO2). At the 0th, 10th, 20th and 30th minutes of the endurance exercise, it was requested to MR with CHO (6.4% maltodextrin), sodium chloride (6.4%) solution and water (placebo) or no rinsing (control).&#x0D; Results: As a result of the analyzes performed with 3 × 4 ANOVA, the power output variables obtained by repeated sprint performance [peak power, average power, minimum power (W, W/kg) and fatigue index (%)] and fatigue variables (heart rate, blood lactate level and rate of perceived exertion) between sessions were not found to be significantly different.&#x0D; Conclusion From the obtained results, it may be concluded that the method and stimuli used in this study seem insufficient to affect the outcome variables of physical performance.

Effects of Different Levels of Weightlifting Training on Bone Mineral Density in a Group of Adolescents

The aim of the current study was to evaluate the effects of different levels of weightlifting training on bone mineral density (BMD) at different body sites (whole body (WB), lumbar spine (LS), femoral neck (FN), upper limbs (UL) and lower limbs (LL)) in a group of adolescents. Three groups of pubertal boys aged 13-15 years were recruited, including a control group (which included 13 untrained adolescents), a moderately trained group (which included 13 non-elite weightlifters, with four sessions of 2 hours per week) and a highly trained group (which included 13 elite weightlifters, with eight sessions of 2 hours per week). The three groups were paired for age and maturation index (using Tanner stages). Body composition, bone mineral content (BMC) and BMD were evaluated by dual-energy X ray absorptiometry (DXA). Physical performance variables (including weightlifting specific exercises, counter movement jump and squat jump) were measured using validated methods. Results showed that the values of BMD and physical performance variables were greater in the group of elite weightlifters compared to the group of non-elite weightlifters and the control group. In addition, the values of BMD and physical performance variables were higher in the group of the non-elite weightlifters compared to those of the control group. After adjusting for lean mass and squat jump, lumbar spine BMD, FN BMD, UL BMD and LL BMD remained significantly higher in the elite weightlifters’ group compared to the two other groups. In conclusion, the current study suggests that elite adolescent weightlifters have greater bone health parameters compared to moderately-trained adolescent weightlifters and untrained adolescents.

Impact of technical and physical performance on match outcome over five elite European soccer seasons.

The technical and physical performance, a key part of overall soccer performance, tend to evolve due to changes in game rules, playing styles, and training methodology. Nevertheless, little has been reported in the literature on how match performance has changed over time in elite championships and leagues. Thus, this study aimed to assess the impact of selected technical and physical team performance indicators on match outcome over five seasons in the Russian Premier League. Twenty-two technical and physical team performance variables, recorded with an optical tracking system, were examined in 1186 matches played in the Russian Premier League during the 2016-2017 to 2020-2021 seasons. For pooled data in all examined seasons, shots on target were higher in won vs. drawn and lost matches. Percentage of challenges won was higher in won vs. drawn and lost matches. Sprint distance, counterattacks, shots, interceptions, recoveries, crosses, and the percentage of successful tackles all showed small though significant differences between match outcomes. Slightly greater odds of a more favorable match outcome were involved by increases in all selected variables, except crosses, showing an opposite effect. In the 2020-2021 season, ball possession time reported a slightly higher impact on match outcome than in previous seasons. The present results show that some technical performance variables have a great effect on match outcome, while other technical indicators and physical metrics have a smaller though still potentially relevant impact. These effects do not substantially differ across the five examined seasons.

Effects of Sodium Bicarbonate Supplementation in Martial Arts

Abstract The aim of this systematic review was to evaluate the effects of consuming sodium bicarbonate (NaHCO3) and to gain insight into the nature of any changes in performance following NaHCO3 supplementation among combat sport athletes. The analysis of the results provides compelling evidence in favor of acute or chronic NaHCO3 supplementation as an ergogenic substance which could have an impact on several aspects of performance in judo [23, 31, 32], taekwondo [17, 20], karate [17, 33] [28, 29], wrestling [18, 19], jiu-jitsu [32] and boxing [16]. Acute or chronic NaHCO3 supplementation is effective in the improvement of several variables of physical performance in combat sports during testing and simulated matches. Enhanced performance resulted in the increased capacity of the glycolytic system. However, the positive effects of its use are most often visible following the onset of fatigue. In addition, the use of NaHCO3 is associated with an increased concentration of lactate in the blood. This systematic review provides data relevant for sports professionals and athletes alike regarding the use of NaHCO3 as a supplement, prior or during training and matches.