BACKGROUND:Accurate quantification of mechanical power output is fundamental for performance analysis in road cycling. However, access to power meter data is often limited in research and applied contexts. The aim of the present study was to develop and validate a physics-based framework to estimate power outputs in professional cycling with publicly available data. METHODS:Performance data from professional cyclists who completed the uphill individual time trial to Peyragudes in the 2025 Tour de France were obtained from publicly available sources. Mean power output was estimated using a mechanical model that accounts for gravitational, aerodynamic, and rolling resistance forces, incorporating rider mass, course characteristics, velocity, and altitude-derived air density. Estimated values were compared with power meter data available from riders' publicly shared activity files. RESULTS:The comparison across 28 professional cyclists showed a good level of agreement between estimated and measured power outputs (mean absolute error = 14.07 W; Mean absolute percentage error = 3.65%). The model exhibited a small mean bias of -5.43 W where the model slightly underestimated the reported power. Bland-Altman analysis yielded 95% limits of agreement from -36.27 to 25.41 W with 26 of 28 observations within these limits. CONCLUSIONS:These results demonstrate that cycling power during sustained climbing efforts could be approximated using simple externally observable variables. This approach may represent a useful tool for reconstructing performance when direct power meter data are unavailable in professional cycling.
BACKGROUND:Sleep hygiene strategies (SHS) are practical, evidence-informed recommendations to enhance both the quantity and quality of sleep in athletes. However, little is known about how these strategies could be communicated and implemented in practice. The primary objective of this study is to investigate how different methods of delivering SHS (written vs. verbal) affect sleep hygiene and sleep parameters in athletes. METHODS:The study was a three-arms randomized controlled trial (ClinicalTrials.gov Identifier: NCT07083544) involving track and field athletes competing at the regional or national level (N.=66). Athletes were randomized to either a control group (CON=22), a written SHS group (W-SHS=22), or a verbal SHS group (V-SHS=22). Sleep characteristics were assessed by actigraphy and sleep diary during a ten-day baseline period (T0) and a ten-day intervention period (T1). Six objective sleep parameters and the Sleep Regularity Index were assessed. Participants also completed a training diary and the Sleep Hygiene Index (SHI). RESULTS:No statistical differences were found between and within groups in training and sleep parameters, but SHI scores improved significantly in the intervention groups between T0 and T1, with differences compared to the control group. A non-significant improvement in total sleep time was observed in the intervention groups, primarily due to earlier bedtimes. CONCLUSIONS:While significant differences in objective sleep measures were not observed, the trends suggest that both written and verbal SHS interventions can modestly improve sleep-related behaviors, particularly by encouraging earlier bedtimes and slightly extending total sleep duration.
BACKGROUND:Childhood is a critical period for physical and respiratory development. Although Taekwondo training is known to improve physical fitness, limited evidence exists regarding the effects of training duration on respiratory muscle function and its association with physical fitness in children. METHODS:Sixty-four male Taekwondo practitioners aged 8-10 years were categorized into three groups based on training experience (Gup, N.=20; 1st Poom, N.=29; 2nd Poom, N.=15). Body composition, basic physical fitness, isometric muscle strength, and inspiratory muscle function were assessed. Differences among groups were analyzed using one-way ANOVA. Pearson's correlation coefficients were used to investigate the relationships between respiratory function, basic physical fitness, muscular strength, and total training duration. RESULTS:The 2nd Poom group demonstrated significantly superior performance in basic fitness (grip strength, standing long jump, side-step, and shuttle run) compared to the Gup and/or 1st Poom groups. Regarding respiratory function, only the 2nd Poom group showed significantly higher S-index, peak inspiratory flow (PIF), and energy values compared to the Gup group. Furthermore, significant positive correlations between respiratory function and physical fitness variables were observed exclusively in the 2nd Poom group. Total training duration was positively correlated with S-index, PIF, and energy across all participants. CONCLUSIONS:Longer duration of Taekwondo training in childhood is associated with enhanced basic physical fitness, greater muscle strength, and better respiratory muscle function. These findings suggest that sustained Taekwondo practice may provide sufficient stimulus to promote the co-adaptation of the respiratory and neuromuscular systems.
BACKGROUND:The negative impact of excess adipose tissue on aerobic capacity in endurance athletes is now considered well-established. However, there is a lack of research examining this relationship in team sport athletes. METHODS:Thirty-eight soccer players (mean age 23.60±4.22 years) from a leading Russian Premier League team participated in the study. On the first day of the pre-season training camp, participants underwent skinfold measurements according to the International Society for the Advancement of Kinanthropometry standards and a treadmill test with gas analysis. RESULTS:Correlation analysis showed moderate inverse associations between adiposity markers and VO2-derived outcomes. Higher body fat percentage was associated with lower relative VO2max and vVO2max, while the sum of eight skinfolds showed a similar direction of association. However, after FDR correction, these associations should be interpreted cautiously. In prespecified HC3-robust regression models, each 1 percentage point higher body fat was associated with -1.93 mL·kg-1·min-1 lower relative VO2max and -0.49 km·h-1 lower vVO2max. Each 10 mm higher sum of eight skinfolds was associated with -1.77 mL·kg-1·min-1 lower relative VO2max and -0.38 km·h-1 lower vVO2max. Model performance under leave-one-out cross-validation was limited, indicating weak individual-level predictive accuracy. CONCLUSIONS:Higher adiposity markers were directionally associated with lower relative VO2max and vVO2max in elite adult male soccer players. However, the cross-sectional design, modest sample size, high FDR-adjusted q-values, and limited cross-validated performance indicate that the findings should be interpreted as exploratory group-level associations rather than robust individual-level prediction.
BACKGROUND:Parkour is a discipline centered on adaptive whole-body movement through complex environments, yet scientific evidence on its physical performance demands remains limited. METHODS:This cross-sectional observational study aimed to profile the athletic capacities of experienced traceurs, determine whether chronological age or accumulated parkour-specific experience better predicts performance, and explore associations between a parkour-specific task and general physical tests. Thirty-six male traceurs (24.1±5.2 years old; 9.6±4.4 years of experience) completed a test battery including countermovement jump with arm swing (CMJ+), standing long jump (SLJ), triple horizontal plyometric jump (3HPJ), 40 m sprint (Sp40), change-of-direction t-test, and five climb-ups for time (5CUFT). Participants were stratified by age (≤23 vs. >23 years) and experience (≤10 vs. >10 years). RESULTS:Age was not significantly associated with performance, whereas years of experience correlated positively with SLJ (ρ=0.49, P=0.002), and 3HPJ (ρ=0.45, P=0.006), and negatively with 5CUFT time (ρ=-0.56, P<0.001). The more experienced group outperformed less experienced peers in 5CUFT (P=0.008, PS=0.21). Additionally, 5CUFT performance correlated negatively with CMJ+ (ρ=-0.43, p=0.01), SLJ (ρ=-0.64, P<0.001) and 3HPJ (ρ=-0.65, P<0.001), and positively with t-test (ρ=0.38, P=0.021). Sp40 showed a non-significant positive trend (ρ=0.32, P=0.054). CONCLUSIONS:These findings suggest that accumulated parkour practice is more strongly associated with physical performance than chronological age. The level of significance was set at P≤0.05.
BACKGROUND:World Lacrosse Sixes (Sixes) is a new variant of the sport of lacrosse and lower limb injuries are highly prevalent. Currently, no studies have been conducted that identify the modifiable injury risk factors associated with this variant. The aim of this study was to observe the acute effects of Sixes lacrosse gameplay on lower limb injury risk factors in male international Sixes lacrosse players. METHODS:Ten international male outfield Sixes lacrosse players (24.8±2.6 years, 180.2±8.8 cm, 90.1±7.6 kg) performed isometric plantar flexion strength, ankle dorsiflexion range of motion, and countermovement jump pre- and postcompetitive match play. RESULTS:No significant changes were observed in plantar flexion strength in either the dominant or non-dominant limb. A small, yet statistically significant increase in dorsiflexion range of motion was found in the non-dominant limb (P≤0.001, g=0.31), while changes in the dominant limb were trivial and non-significant. Countermovement jump performance showed no significant differences in jump height, time to take-off, or reactive strength index-modified (P>0.05). A small increase in countermovement depth (P=0.052, g=-0.26) and body mass (P=0.006, g=0.09) was observed postmatch. CONCLUSIONS:Participation in a single Sixes lacrosse match resulted in a small increase in ankle dorsiflexion and altered countermovement jump strategy. Further research is needed to assess the cumulative effects of repeated match-play in tournament settings.
BACKGROUND:CrossFit® has experienced rapid global growth, yet scientific research often fails to reflect the realities of training and competition in this sport. Studies frequently rely on inconsistent terminology, non-specific testing protocols, and heterogeneous samples, limiting the ecological validity and practical application of findings. This critical commentary aims to evaluate the methodological challenges in CrossFit® research and to highlight the importance of contextualizing scientific inquiry through the perspectives of coaches actively working within the sport. METHODS:A targeted review of the CrossFit® literature was conducted, with a focus on sampling descriptions, testing protocols, and training monitoring approaches. In addition, semi-structured interviews were conducted with five national and international-level CrossFit® coaches. Analysis of coach responses was used to contextualize gaps in the literature. RESULTS:Coaches reported relying primarily on competition results, training observations, and subjective feedback to guide programming, rather than standardized physical testing or technology-based monitoring. The remote nature of many coach-athlete relationships further complicates data collection and training analysis. CONCLUSIONS:CrossFit® research must improve its methodological rigor by adopting sport-specific assessments, clearly defining participant characteristics, and embracing the realities of coaching practice. Integrating qualitative insights and prioritizing ecological validity will help bridge the gap between science and the sport's unique demands.
BACKGROUND:Stop-ball small-sided games (SSGs-SB) have been proposed as an effective scoring method to influence physical and physiological responses in young soccer player. The aim of present study is to examine the differences in external and internal load variables across U-13, U-14 and U-15 players during SSGs-SB. METHODS:Ninety-six male soccer players (32 players in each group) from teams competing in Italian regional championship were involved. The experimental design consisted of a 4 vs. 4 played on a 25×20 m pitch, including 4x3' of work separated by 2 min of passive recovery. During SSG-SB, players were monitored using 18.18 Hz global positioning system devices (GPEXE® SYSTEM, EXELIO srl, Udine, Italy). Total distance, peak velocity, distance covered at high-speed running 13-18 km∙h-1, sprint running >18 km∙h-1, number of sprint, acceleration >2.5 m∙s-2, deceleration <-2.5 m∙s-2, maximal acceleration and deceleration, high metabolic load distance and rating of perceived exertion were measured. RESULTS:U-15 team exhibited greater physical demands compared with U-13 team (P<0.001 for all comparisons), whereas younger counterparts significantly (P<0.001) reported higher RPE scores than U-15 players. CONCLUSIONS:The present study suggests that SSGs-SB designs should be tailored according to chronological age to support an appropriate long-term development process in youth soccer players.
BACKGROUND:Dehydration is common in tennis, yet the relationship between fluid loss and muscle strength during actual match play remains unclear. This study examined the association between body water loss and changes in muscle strength in competitive university tennis players. METHODS:A cross-sectional study was conducted with 20 male university tennis players (age: 20.6±1.6 years) during the regional qualifying round of the All Japan Student Indoor Tennis Championships. Body mass, grip, back, and toe strength were measured before and immediately after matches. Body water loss was calculated from body mass changes, and associations between fluid loss and changes in muscle strength were examined using Pearson's correlation coefficients. RESULTS:Mean body water loss was 0.7±0.8%. Although overall pre-post differences in muscle strength were not significant, body water loss was negatively correlated with changes in right-hand grip strength (r=-0.54, P<0.05) and toe strength in both feet (right: r=-0.45, P<0.05; left: r=-0.58, P<0.01). After adjusting for total games played, the associations remained significant for right-hand grip strength (partial r=-0.60, P=0.007) and left toe strength (partial r=-0.58, P=0.009). Subjective fatigue increased significantly but was not associated with strength changes. CONCLUSIONS:Mild body water loss during competitive tennis matches was associated with reductions in muscle strength in some frequently used limbs. However, given the modest level of dehydration and the correlational design of the study, these findings should be interpreted cautiously, as match workload may have influenced both fluid loss and neuromuscular responses.
BACKGROUND:The aim of this study is to examine relative five-repetition maximum (RM) box squat, rear-foot elevated split squat (RFESS), leg extension strength and vertical jump scores in amateur athletes who have returned to sport following anterior cruciate ligament (ACL) reconstruction. METHODS:Overall, 53 amateur athletes completed a strength and vertical jump assessment including 5RM box squat, RFESS, Leg Extension, countermovement jump (CMJ), single leg (SL) CMJ and SL drop jump (DJ). RESULTS:Relative 5RM values of 1.16, 0.6 and 0.65 were found for box squat, RFESS and leg extension respectively. Significant main effects of limb were observed across most outcomes, with the ACL-reconstructed limb showing lower strength and jump performance. Males outperformed females on all strength and jump metrics. A main effect of graft type was found for leg extension strength, but post-hoc comparisons were not significant. Time from surgery did not moderate the effects of limb, gender, or graft type, except for one interaction with eccentric deceleration impulse. CONCLUSIONS:Single joint strength and vertical jump scores were lower in the ACL reconstructed limb in comparison to the uninvolved limb, whereas no differences were found in RFESS. Females showed lower relative scores in all tests, whereas no difference was found according to graft type. Time from surgery did not moderate the effects of limb, gender and graft type on strength and vertical jump scores, except for SLCMJ eccentric deceleration impulse.
The pursuit of pharmacological enhancement in sport has evolved from the widespread use of anabolic-androgenic steroids (AAS) to novel agents such as peptides and peptide analogues. Marketed as more selective and ostensibly safer alternatives, peptides-including growth hormone secretagogues (e.g., Ipamorelin), growth hormone-releasing hormone analogues (e.g., CJC-1295, Sermorelin), and synthetic fragments (e.g., Frag 176-191, KPV)-are promoted for muscle growth, fat metabolism, recovery, and anti-inflammatory effects. Their pharmacological profiles, including enhanced stability and receptor selectivity, have made them attractive in both medical research and bodybuilding communities. Despite their growing popularity, the clinical evidence supporting peptide use in sport is limited. Most published studies examine therapeutic applications under controlled dosing regimens, not the supraphysiological or combined protocols common in bodybuilding. Emerging data highlight potential risks: cardiovascular strain, insulin resistance, dyslipidemia, and psychiatric instability. The largely unregulated supply chain exacerbates these dangers, as products are often mislabeled or contaminated. Regulatory bodies such as the World Anti-Doping Agency (WADA) have responded by expanding detection technologies, yet analytical challenges remain due to peptides' structural similarity to endogenous hormones and short half-lives. Beyond elite sport, the extent of peptide use in the general population is unknown. Anecdotal reports and widespread promotion on social media suggest growing uptake among recreational gym-goers, including younger individuals, but prevalence studies are lacking. This represents a critical gap in current knowledge. In conclusion, peptides represent a new phase in performance enhancement but remain experimental substances with poorly defined long-term risks. Until longitudinal data clarify their safety and prevalence, peptide use in both competitive and recreational settings should be considered high-risk and ethically problematic.
BACKGROUND:Radial shockwave therapy (rSWT) is widely used for musculoskeletal conditions, but its use and efficacy in athletic recovery are relatively unexplored. Multi-day basketball tournaments result in repeated physical stress on players, leading to muscle soreness that can impair recovery. The aim of this study was to investigate the feasibility and possible efficacy of rSWT in applied sports. Specifically, to examine the feasible effectiveness of post-match rSWT in reducing muscle soreness and improving perceived recovery, fatigue, and sleep quality in master's basketball players during a tournament. METHODS:Using a parallel group design, 61 male and female basketball players allocated to intervention or control, either a rSWT treatment group (N.=30) or a control condition (N.=31) during an international tournament. The participants in the rSWT group received treatment within four hours after each game to quadriceps, hamstrings, and calves of both legs. Participants in the control group received no treatment. Daily self-report questionnaires before the tournament (baseline) and on each day of competition for muscle soreness (Likert Scale), perceived recovery (PRS), fatigue (VAS-F), and quality of sleep (Consensus Sleep Diary) were completed. RESULTS:Fifty-six participants completed the study. The rSWT group showed lower muscle soreness than controls (P<0.001), with a 35% reduction compared to control by Day 4. Perceived recovery was improved in the rSWT group compared to the control (P<0.004). No differences were found between groups for fatigue or sleep quality. CONCLUSIONS:Post-game rSWT is a feasible and effective approach to reduce muscle soreness and improve perceived recovery during fixture congestion experienced during international competition. Although fatigue and sleep were not affected and the underlying mechanisms remain to be elucidated, these observations support the potential for rSWT in a new application as a tool to facilitate exercise recovery.
