BMC Sports Science Medicine and Rehabilitation最新文献

Background: Exercise-induced fatigue is a physiological state characterized by performance decline. The Visual Analog Scale (VAS) is one of the most commonly used subjective methods for evaluating exercise-induced fatigue. However, there is a limited interpretation of how much a change in this method indicates a fatigue status that matters to the exercise performance due to the lack of a well-established minimal important difference (MID).

Methods: This study is a secondary analysis of data from three trials. We analyzed individual participant data before and after exercise-induced fatigue. Anchor-based methods were used to determine the MID of the VAS for fatigue, using Countermovement Jump (CMJ) height as an anchor. Specifically, the MID was calculated using mean change, receiver operating characteristic (ROC) curve analysis, and linear regression methods.

Results: Data from 71 participants (80.28% male, 22.85 ± 2.51 years), corresponding to 230 person-time measurements, were included in this analysis. The CMJ height fulfilled the requirements to be used as an anchor. MIDs for mean change, ROC curve, and linear regression analysis were 48.51, 44.13, and 43.08, respectively. The Youden's Index indicated that the MID calculated by the mean change method was the most relevant and reliable in distinguishing between fatigued and non-fatigued states.

Conclusions: This study establishes a MID (48.51) for interpreting changes in VAS scores. Future research utilizing VAS to assess exercise-induced fatigue should not only consider statistical differences but also examine whether the changes meet the MID threshold to interpret the actual impact of interventions.

Trial registration: Chinese Clinical Trial Registry (ChiCTR), Registration Number: ChiCTR2500095599 (Retrospectively registered; registration date: 09/01/2025).

Introduction: Endurance-specific activities in diverse terrains, including alpine regions, necessitate the transportation of supplementary equipment, thereby necessitating an adaptation of the load intensity. To ascertain the impact of these loads on acute endurance performance and load intensity, it was essential to conduct tests with additional loads to predict the individual reaction to carrying additional loads on performance. The formulas derived in this study facilitate the prediction of exercise adaptation when carrying additional loads.

Purpose: This study aimed to develop and validate a formula-based prediction of performance adaptation when carrying additional loads to guide load intensities and training instructions.

Methods: The 105 participants, 54 male and 51 female, had a mean age of 23.7 years, a mean height of 174.0 cm, a mean weight of 71.7 kg, and an aerobic capacity of 48.6 mL/kg/min-1. Two treadmill ramp tests were conducted in a laboratory setting, with and without additional loads, to assess the adaptation of cardiopulmonary parameters. Both tests were conducted at 4 km/h and an incline of 1%, with the speed increasing by 1 km/h each minute until the subject reported feeling exhausted. The statistical analysis was conducted via stepwise linear regression. The formulas were validated with an independent t-test on an additional dataset, and the equivalence was determined with a two-sided test (TOST).

Results: Based on these tests, regressions were calculated for speed (p < 0.001) and heart rate (p < 0.001) with additional loads, and formulas were derived to predict the adaptations of heart rate and speed to additional loads. The results revealed that the backpack weight, sex, and individual parameters without load were the most accurate predictors of performance with additional load carriage (p < 0.001). The validation of the formulas, using a sample of N = 64, was statistically equivalent.

Conclusion: The formulas can predict the adaptation of running speeds and heart rates at the ventilatory thresholds with different additional loads. This is useful for controlling optimal load intensities in endurance performance with additional loads, to prevent overstraining. This is particularly relevant in mountain sports or military marches, where optimizing loads and mitigating falls due to overstraining is crucial.

Background and aims: Body fat is a key body composition parameter monitored in soccer. Identifying reliable alternatives to laboratory techniques for assessing body fat during the competitive period is essential. This study aimed to evaluate the cross-sectional and longitudinal validity of anthropometric prediction equations in elite female soccer players.

Methods: Eighteen female soccer players (age: 26.6 [3.8] years; height: 168 [6.3] cm; body mass: 64.1 [7.4] kg; body mass index: 22.7 [1.9] kg/m²) from an Italian Serie A team were assessed at four time points during a competitive season. Fat mass was estimated using anthropometric equations by Evans and Warner and compared to dual-energy X-ray absorptiometry (DXA), which served as the reference method.

Results: Cross-sectional agreement analysis revealed a bias of -4.5% with Warner's equation, while Evans's equation showed no bias compared to DXA, with coefficient of determination (R²) values of 0.69 and 0.70, respectively. Both methods showed a negative association (Evans: r = -0.53, Warner: r = -0.63) when the difference between the values and the mean with DXA were correlated. Longitudinal agreement analysis showed no significant differences in fat mass changes between the anthropometric equations and DXA, with R² values ranging from 0.68 to 0.83. The 95% limits of agreement between the methods for individual changes in fat mass ranged from - 3.3 to 3.2%. Furthermore, no significant changes (p > 0.05) in fat mass were observed over the season with any method.

Conclusions: At the group level, Evans's equation provides valid estimates of fat mass, whereas it may overestimate values in players with low body fat and underestimate them in those with high fat mass. The Warner equation showed the same trend as Evans at the individual level, also resulting in poor accuracy at the group level. Despite this, both anthropometric equations are valid alternatives to DXA for monitoring fat mass changes during the season, with Evans's equation showing superior overall performance.

Background: Previous studies have demonstrated the effects of SAQ training on sprint, change-of-direction, and jump performance in soccer players. However, further research is needed to assess its broader impact on different athletic populations and performance metrics. This study aims to expand the existing evidence by incorporating a wider range of outcomes and providing a more comprehensive analysis of SAQ training effects.

Methods: A thorough search of databases, including Web of Science Core, SPORTDiscus, PubMed, and SCOPUS, was conducted, with data up to July 2024. The PEDro scale assessed study quality and RevMan 5.3 evaluated bias risk. Effect sizes (ES) were calculated from means and standard deviations, with heterogeneity assessed using the I² statistic. Publication bias was evaluated using an extended Egger test.

Results: Eleven RCTs involving 499 healthy athletes from sports such as soccer, basketball, tennis, and handball met the inclusion criteria. The SAQ interventions lasted between 4 and 12 weeks, with a frequency of two to three sessions per week. The analysis revealed significant improvements in 5-meter sprint (ES = 0.63, p < 0.01), 20-meter sprint (ES = 0.49, p < 0.01), 30-meter sprint (ES = 0.55, p = 0.015), change of direction (COD) performance (ES = 0.39, p < 0.01), reaction time (ES = 0.52, p = 0.01), lower limb power (ES = 0.96, p < 0.01), and flexibility (ES = 0.57, p < 0.01), with effect sizes ranging from small to moderate. Subgroup analysis indicated that only session duration had a near-significant effect on COD performance (≤ 60 min: ES = 0.58; >60 min: ES = 0.24; p = 0.059).

Conclusions: SAQ training effectively enhances sprint performance, COD ability, reaction time, lower limb strength, and flexibility, with effect sizes ranging from small to moderate. The findings suggest that shorter training durations (≤ 60 min) may be more beneficial for improving COD performance, although this effect did not reach statistical significance. Further trials are recommended to determine the optimal training dosage, along with high-quality studies covering a broader range of sports, particularly in athletes aged 14 to 18.

Background: The influence of circadian rhythms and menstrual cycle phases on athletic performance and psychological responses is critical for optimizing training and competition strategies for female athletes. This study aimed to investigate the effects of time of day and menstrual cycle phases on the physical performance and psychological responses of elite female Tunisian volleyball players.

Methods: Thirteen elite female volleyball players were assessed during three different phases of their menstrual cycle (menstrual, follicular, and luteal) and at two different times of day (morning and evening). Physical performance was evaluated using the Modified Agility Test (MAT), Reactive Agility Test (RAT), and Repeated Sprint Ability (RSA) Test. Psychological responses were measured using the Profile of Mood States (POMS), Hooper's Questionnaire, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Vis-Morgen Questionnaire, and Spiegel Questionnaire.

Results: Significant effects of menstrual cycle, time of day, and competition on physical performance, cognitive function, mood, and sleep parameters were found. Physical performance, including the Countermovement Jump (CMJ), the Modified Agility T-test (MAT) and the Reactive Agility test (RAT), was higher in the afternoon than in the morning across all menstrual phases (CMJ: p < 0.001, η² = 0.836; MAT: p < 0.001, η² = 0.777; RAT: p < 0.001, η² = 0.859). After the competition, performance decreased significantly, especially in the follicular and luteal phases. As measured by the Stroop test, cognitive function showed significant diurnal effects (p < 0.001, η² = 0.910), with pre-competition performance being better in the afternoon. Mood disturbances (POMS) increased after the competition, especially in the morning and during the luteal phase (p < 0.001, η² = 0.961). Sleep parameters were significantly influenced by time and menstrual cycle, with higher fatigue (Hooper score: p < 0.001, η² = 0.754) and poorer sleep quality (PSQI: p < 0.001, η² = 0.627) in the morning, especially after the competition.

Conclusion: Our results suggest that aligning high-intensity training and competitions with afternoon circadian peaks may enhance physical and cognitive performance in elite female athletes. Recovery strategies and workload adjustments should account for menstrual phases, particularly reducing morning demands during the luteal phase to mitigate fatigue and mood disruptions. Integrating circadian timing with menstrual cycle monitoring offers a practical, evidence-based approach to optimize athlete readiness and resilience.

Background: Video Assistant Referee (VAR) as a high-tech aid was introduced into football in 2018 to enhance the officiating accuracy of referees. At the 2020 UEFA European Championship, VAR was used for the first time. This study aims to investigate the impact of VAR on the UEFA European Championship.

Methods: The sample includes all matches of EURO 2016 (without VAR, n = 51) and EURO 2020 (with VAR, n = 51), in a total of 102 matches. For each game, nine VAR-related variables were recorded: goals, penalties, red cards, yellow cards, fouls, offsides, first-half game time, second-half game time and total game time. The tournaments pre and post the introduction of VAR were compared using a Mann-Whitney U test.

Results: The results of this study revealed that the introduction of VAR led to a significant increase in the first-half match time (Z = 2.52, p = 0.012, ES = 0.13), the second-half match time (Z = 2.80, p = 0.005, ES = 0.16), total game time (Z = 3.74, p < 0.001, ES = 0.28) and the number of goals (Z = 2.25, p = 0.024, ES = 0.10), whereas a significant decrease in yellow cards (Z=-2.55, p = 0.011, ES = 0.13) was observed.

Conclusions: The findings of this study may have practical implications for optimizing VAR-related implementation regulations and the referee's officiating strategies at the UEFA European Championship competitions.

Purpose: To assess the effectiveness and adverse events of postoperative physical exercise on health-related quality of life (HRQL) in patients who have undergone surgery for oesophageal or gastric cancer.

Methods: We conducted a systematic review and meta-analysis and reported it according to the preferred reporting items for systematic reviews and meta-analyses. (PRISMA) guidelines. Randomised controlled trials (RCT) that investigated HRQL factors following physical exercise interventions in patients undergoing oesophageal or gastric cancer surgery were included. Studies including participants who had undergone oesophagectomy or gastrectomy for cancer, of either sex and were 18 years or older were included. Participants with other cancers were excluded. Medline, Embase, CINAHL, Cochrane Library, PEDro, and trial registries were searched for studies from inception until February 2025. Results were synthesised using meta-analyses. Two independent reviewers assessed the risk of bias using the Cochrane risk of bias tool 2.0, and the grading of recommendations assessment, development and evaluation (GRADE) was used to evaluate the overall certainty of the evidence. PROSPERO ID CRD42022358493.

Results: Three studies enrolling 284 patients undergoing oesophagectomy were included, of which two were assessed at high risk of bias and one at some concerns. The global quality of life score from the European Organisation for Research and Rreatment of Cancer (EORTC) quality of life questionnaire Cancer QLQ-C30 was used to assess HRQL in all the included studies. The score ranges from 0 to 100, with higher scores indicating a better HRQL. Physical exercise therapy had no discernible impact on HRQL compared to the control group (mean difference 0.77 [95% CI -4.36, 5.90]. However, the quality of evidence was very low, which should be considered when interpreting the results as they can differ substantially from the true effects.

Conclusion: We found a significant lack of information about the effects of post-surgery physical exercise compared to standard care in patients who have undergone oesophagectomy or gastrectomy for cancer. Based on the current very low certainty evidence, the effectiveness on HRQL and the safety of postoperative physical exercise in patients treated with oesophagectomy for cancer is uncertain. We found no studies investigating gastric cancer and exercise.

Background: We investigated associations of movement behaviors (moderate-vigorous physical activity, light physical activity, and stationary time) with various parameters measured during cardiopulmonary exercise testing. We applied compositional data analysis to account for the relative contributions of different movement behaviors to the overall time budget of the waking day.

Methods: We used data from 1,396 participants of the cross-sectional population-based Study of Health in Pomerania (SHIP-TREND-1), who provided valid accelerometer data worn on the hip for seven days during waking hours and participated in cardiopulmonary exercise testing on a cycle ergometer (n = 1,396 participants with a mean age of 57.1 (SD 13.2, 51% men). Linear regression models applying compositional data analysis were used to examine associations of proportions of movement behaviors (exposure) with parameters derived during cardiopulmonary exercise testing (outcome) normalized for body weight and stratified by sex. Models were adjusted for age, education, smoking, and partnership, except the %predicted VO₂peak model, where age was omitted, as it is part of the calculation of the %predicted VO₂peak. In models examining O₂pulse or HRmax, individuals using beta blockers were excluded.

Results: In males and females, more time spent in moderate-to-vigorous physical activity was associated with greater VO₂VT1, VO₂peak, and VO₂ recovery after 60 s (all p < 0.01). Greater moderate-to-vigorous physical activity was also related to higher %predicted VO₂peak and maximum heart rate in males and to higher VO₂/work in females (all p < 0.01). In both sexes, more time in stationary time was associated with less %predicted VO₂peak (p < 0.01). More light intensity physical activity was associated to higher %predicted VO₂peak in both sexes and with lower VO₂/work in women (all p < 0.01). Greater stationary time was related to less VO₂/work, VO₂VT1, and VO₂peak in males and to less VO₂ recovery after 60 s and O₂pulse in females (p values < 0.05).

Conclusion: Moderate-to-vigorous physical activity (positive) and stationary time (inverse) influence parameters derived during cardiopulmonary exercise testing irrespective of age, smoking, and living in a relationship. The sex specific effects were rather small. Hence, promoting physical activity should be encouraged to increase cardiorespiratory fitness.

Background: Limited lower-extremity flexibility has long been debated as a physical risk factor contributing to low back pain in various populations. However, its impact on younger populations, particularly elementary school-aged softball players, remains unclear. This study aimed to explore the relationship between limited lower-extremity flexibility (iliopsoas, hamstrings, and quadriceps femoris) and low back pain in elementary school-aged softball players.

Methods: This cross-sectional study included 521 elementary school-aged softball players (469 males and 52 females; mean age, 10.7 years) who participated in annual medical evaluations from 2017 to 2019. Lower-extremity flexibility was assessed once during annual medical evaluations using the Thomas test for the iliopsoas, straight-leg-raise test for the hamstrings, and heel-to-buttock-distance test for the quadriceps. Additionally, low back pain during the previous season was evaluated through self-administered questionnaires distributed to participants and collected during medical check-ups. The prevalence of low back pain and its association with lower-extremity flexibility were investigated using univariate and multivariable analyses. In multivariable analysis, age, position, body mass index, and total practice time per week were included as explanatory factors.

Results: Overall, 16.9% (88/521) of the players experienced low back pain that required rest during the previous year. After adjustment for confounding factors (age, position, body mass index, and total practice time per week) with a logistic regression model, low back pain showed a significant association with quadriceps muscle tightness (odds ratio: 3.15, 95% confidence interval: 1.51-6.56, P = .002).

Conclusion: Quadriceps femoris tightness may be a significant risk factor for low back pain in elementary school-aged softball players. These findings underscore the importance of assessing quadriceps femoris tightness to prevent low back pain in elementary school-aged softball players.

Trial registrations: Not applicable.

Introduction: Concussion is a common condition, with sources estimating between 1.2% and 6.6% of all ED presentations are related to head injury, and concussion has significant healthcare costs. In April 2023, the UK Government published guidelines for diagnosis and management of concussions in grassroots sport, recommending anyone that has sustained a suspected concussion has a same day review by an appropriate healthcare professional. It is therefore essential that emergency medicine physicians have the required knowledge and use current clinical practice guidelines in managing suspected concussions presenting to their departments. This scoping review aims to review the current literature regarding concussion knowledge, diagnosis and management amongst emergency physicians.

Materials and methods: This scoping review was conducted using the six-step process laid out by Arksey and O'Malley and included 17 papers from January 2012 to February 2023, identified by searching 5 online databases (MEDLINE, Embase, Web of Science, Scopus and Google Scholar) in February 2023 alongside a hand search of references. Search terms relevant to concussion, emergency medicine and medical education were used.

Results: 14 of the 17 papers originated from North America, all studies utilised either an online survey or chart review methodology. 3 papers included an educational intervention. 12 studies looked at all grades of EMPs. 14 of the studies highlighted knowledge gaps amongst EMPs, the 3 that did not specifically mention this were the 3 interventional studies.

Conclusion: EMPs have large knowledge gaps regarding concussion and limited adherence to current guidelines. Efforts should be made at improving these results amongst EMPs. Further research is needed to find the most beneficial and cost-effective approach to improving concussion knowledge of concussion diagnosis and management in EDs, particularly within the UK.