Search Results (26,416)

Background/Objectives: Global population aging is associated with a rising prevalence of malnutrition among adults aged ≥80 years. Gut dysbiosis is linked to immune decline and impaired nutrient absorption, and aerobic exercise may enhance microbial diversity. This study investigated gut microbiota changes after a 12-week aerobic exercise intervention in octogenarians stratified by nutritional status. Methods: A total of 129 nursing home residents (≥80 years) were classified via the Mini Nutritional Assessment Short-Form (MNA-SF) into a healthy group (HG, MNA-SF ≥ 11) and a malnourished group (MG, MNA-SF < 11). Both groups underwent a 12-week brisk walking intervention (three sessions/week, 1 h/session, 40–60% heart rate reserve). Fecal samples were collected at baseline and post-intervention and were analyzed via shotgun metagenomic sequencing. Results: A total of 36 participants completed the intervention (HG = 17, MG = 19). Within-group baseline-to-post-intervention analysis showed no significant changes in alpha or beta diversity in the MG. However, post-intervention between-group comparison revealed higher microbial richness and diversity in the MG vs. the HG, with enrichment of taxa including Faecalibacterium prausnitzii and Streptococcus salivarius. Functional analysis revealed significant enhancements in metabolic pathways related to amino acid biosynthesis, protein synthesis, and quorum sensing in the MG. In contrast, the HG showed limited shifts in microbial diversity but an increase in species involved in carbohydrate metabolism. Conclusions: After 12 weeks, the malnourished group showed higher post-intervention microbial richness and diversity than the healthy group, with differences in taxonomic and predicted functional profiles. Without a non-intervention control group, the microbiota differences observed during the 12-week aerobic exercise period can only be considered observational associations, not causal. Additionally, the high dropout rate (72.1%) limits the generalizability of the findings. Clinical trial registration: The Chinese Clinical Trial Registry on 19 October 2022 (ChiCTR2200064801). Full article

Monitoring eccentric hamstring strength is critical for reducing injury risk in soccer players, yet laboratory-based technologies such as isokinetic dynamometry remain costly and impractical for field use. The purpose of this study was to examine the association and exploratory predictive relationship between variables derived from a smartphone application (My Jump Lab) and eccentric hamstring strength outputs obtained with an instrumented field device (NordBord, Vald Performance, Australia), while also quantifying their absolute agreement during the Nordic hamstring exercise (NHE). Thirty-one professional soccer players from a second-division United Arab Emirates team performed the NHE on the NordBord, while a simultaneous two-dimensional (2D) kinematic analysis was conducted using the My Jump Lab app (version 5.0 for iOS; My Jump Lab, Madrid, Spain). Pearson correlations, linear regression models, and Bland–Altman analyses were used to distinguish linear association/prediction from agreement/interchangeability. Results revealed a very large association between My Jump Lab-derived torque estimates and NordBord peak torque (r = 0.77, p < 0.001), with moderate associations for breakpoint angle (r = 0.42–0.43). A combined regression model using My Jump Lab torque and breakpoint angle explained 69.2% of the variance in NordBord torque (SEE = 15.30 N·m), although this predictive result should be interpreted as exploratory because the variables are task-specific and partly share anthropometric and mechanical determinants. Bland–Altman analysis revealed poor agreement, with a large systematic difference and proportional bias, indicating that My Jump Lab overestimated torque values at higher strength levels (mean bias = +511.9 N·m). Therefore, torque values derived from the app should be interpreted as relative indicators rather than absolute equivalents to instrumented measurements. From a practical perspective, My Jump Lab may offer a low-cost option for broad screening or relative group profiling when instrumented devices are unavailable, but it should not be used as a substitute for instrumented devices or for individual longitudinal monitoring based on absolute torque values. Full article

Team handball is an intermittent sport characterized by variable kinematic and neuromuscular demands, which require precise monitoring to optimize training design. The aim of the present study was to establish data-driven intensity thresholds for external load variables and to examine their distribution across training tasks in elite women’s handball. External load was monitored in 17 professional female handball players during five training sessions within a competitive microcycle using inertial measurement units. Kinematic variables (speed, acceleration, and deceleration) and a neuromuscular variable (jump impulse) were analyzed. A k-means clustering approach was applied to classify each variable into five intensity zones. Subsequently, the distribution of these zones across different training tasks was evaluated. The results showed a predominance of low-to-moderate intensity actions across all the variables, with a progressive reduction in the frequency of higher-intensity efforts. Acceleration values were consistently higher than deceleration across all the zones. Jump impulse also followed a similar distribution, reflecting the neuromuscular demands of training. A task-based analysis revealed clear differences in intensity profiles, with tasks involving opposition eliciting higher proportions of moderate-to-high-intensity actions, while tasks without opposition showed an absence of high-intensity zones. These findings provide objective reference values for external load in elite women’s handball and highlight the importance of task design in modulating physical and neuromuscular demands. The use of data-driven thresholds and ecologically valid training tasks may contribute to more effective and individualized load prescription. Full article

Background/Objectives: Traumatic brain injury (TBI) is increasingly understood as a chronic condition, but the role of early post-injury lifestyle behaviors in later cardiometabolic risk remains unclear. We examined whether lifestyle behaviors reported 1 year after injury were associated with the accumulation of common cardiometabolic risk factors by 5 years in the Traumatic Brain Injury Model Systems (TBIMS) National Database. Methods: This retrospective cohort secondary analysis included adults with followed 1-year and 5-year interviews, complete 1-year data on four behaviors, and the complete ascertainment of hypertension, diabetes or high blood sugar, and high cholesterol at both waves. The exposure was a favorable lifestyle count based on not smoking, non-heavy alcohol use, non-obese body mass index, and sports or exercise at least 10 times per month. The primary endpoint was the incident accumulation of at least two new common cardiometabolic conditions between years 1 and 5. The analytic cohort was an observed-data subset defined by follow-up retention, complete behavior data, paired outcome ascertainment, and baseline at-risk status rather than a random sample of all TBIMS participants. Results: Among 10,057 linked participants with followed interviews at both waves, 9593 were adults, 3182 had complete four-behavior exposure data, 689 had complete cardiometabolic ascertainment, and 581 formed the primary at-risk observed-data cohort. The primary endpoint occurred in 39 participants (6.7%). Each additional favorable behavior was associated with lower odds of the primary endpoint in the adjusted model (odds ratio [OR], 0.63; 95% confidence interval [CI], 0.41–0.98; p = 0.040). The results were similar after adjustment for the 1-year Functional Independence Measure cognitive score and in Firth logistic regression. Because the final cohort was selected and the number of primary events was small, the estimates should be interpreted as exploratory and may not generalize to the broader TBI population. Conclusions: More favorable 1-year lifestyle profiles were associated with lower 5-year cardiometabolic risk factor accumulation after TBI. These findings support prevention-oriented follow-up but do not establish causality or validate a prognostic score. Full article

This study evaluated the validity of the leg stiffness metric provided by the Stryd running power meter against the Morin (2005) sine-wave spring–mass model. Twenty-three highly trained trail runners (11 women) completed a 12 min uphill time trial at +12% grade and one hour of submaximal level running. Leg stiffness was calculated from contact time, flight time, running speed, and leg length using Morin’s method, and compared with Stryd values. Agreement was assessed following the Dhahbi and Chamari Level-1 analytical framework, including intraclass correlation coefficient (ICC_2,1), Bland–Altman analysis, mean absolute percentage error (MAPE), and paired t-tests. Stryd and Morin estimates showed excellent agreement in both conditions: uphill running: ICC_2,1 = 0.96 (95%CI: 0.91–0.98), bias = −0.02 kN·m⁻¹, limits of agreement (LoAs) = [−0.61, 0.58] kN·m⁻¹, MAPE = 2.5% (p = 0.803); and level running: ICC_2,1 = 0.97 (95%CI: 0.93–0.99), bias = −0.04 kN·m⁻¹, LoAs = [−0.62, 0.54] kN·m⁻¹, MAPE = 2.6% (p = 0.505). The Stryd sensor provides valid leg stiffness estimates in highly trained trail runners on both level and inclined terrain. The negligible systematic bias and narrow limits of agreement support the use of Stryd for leg stiffness monitoring in field and laboratory settings. Full article

The association between return-to-sport test batteries (RTS-TBs) and clinical outcomes remains unclear. Previous systematic reviews of RTS-TBs have reported low pass rates; however, these reviews have been limited by substantial heterogeneity. This systematic review aimed to quantify RTS-TB pass rates and examine their association with timing (post-op). Five electronic databases (AMED, CINAHL, MEDLINE, SPORTDiscus, PubMed) were searched on 22 December 2024. Observational studies reporting RTS-TB outcomes as a single pass or fail were included. A random-effects proportion meta-analysis was used to estimate the pooled prevalence of pass rates. A meta-regression was performed to assess the association between test timing and pass rate. Twelve studies (n = 1977) met the eligibility criteria, but five were excluded from the meta-analysis and meta-regression due to overlapping cohorts. From the remaining eight studies (n = 1449), the pooled prevalence of pass rates was 33% overall (95% CI 19 to 47%), 26% (95% CI 18 to 33%) for non-professional athletes, and 73% (95% CI 66 to 80%) for professional athletes, although only a single study focused on professional athletes. No association was observed between the post-operative timing of the test and passing RTS-TB (p = 0.73). The observed RTS-TB pass rates are low, and this may be influenced by the extreme heterogeneity. Although no association was observed between the RTS-TB timing and pass rates, this finding alone cannot confirm causality. Full article

Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental condition characterized by inattention, impulsivity, and executive dysfunction, which may influence both the risk and clinical course of sport-related concussion (SRC). This narrative review aimed to synthesize current evidence on the relationship between ADHD and SRC in athletic populations, with a focus on injury risk, symptom presentation, assessment challenges, and recovery trajectories. A targeted narrative review of the literature was conducted to synthesize current evidence on ADHD and sport-related concussion, with emphasis on literature published within the past 10 to 15 years. Studies were selected based on relevance to concussion risk, neurocognitive and symptom assessment, and recovery outcomes in athletes with ADHD, with priority given to methodologically rigorous research involving athletic populations. Available evidence suggests that athletes with ADHD are at an increased risk of SRC, with some studies reporting an approximately twofold increase, potentially due to impairments in inhibitory control and attention regulation. ADHD is also associated with elevated baseline symptom reporting, lower neurocognitive performance, and higher rates of invalid baseline testing, complicating post-injury assessment. Findings regarding recovery are mixed; however, emerging evidence indicates that ADHD may be associated with prolonged return-to-learn and return-to-sport timelines in some populations. Stimulant medication may influence risk and recovery, though results remain inconsistent. Overall, ADHD presents unique challenges in the clinical management of SRC, necessitating individualized, multidisciplinary approaches. Integrating neurocognitive and behavioral considerations into concussion protocols may improve diagnostic accuracy and optimize recovery in this population. Full article

The transition phase often causes athletes to lose the benefits of warm-up, so this study aimed to assess the effects of two re-warm-up protocols and a control condition without re-warm-up on 100 m freestyle performance and the kinematic variables (stroke length (SL), stroke rate (SR), and stroke index (SI)), subjective perception of effort (RPE), and physiological variables (heart rate (HR), temperature (T), and blood lactate concentration (La⁻)). Twenty competitive-level swimmers completed a dryland and water warm-up, followed by a 30 min transition phase and a 100 m freestyle simulation. Over 30 min, each swimmer randomly performed one of three re-warm-up protocols: control (remaining seated), dryland (explosive exercises), and water (race-pace series). The three experimental re-warm-up protocols affected 100 m freestyle performance (p = 0.019; η²p = 0.189). Post hoc comparisons showed that dryland was faster than control (−0.68%, p = 0.009), whereas no significant difference was observed between water and control (−0.52%, p = 0.234). No significant differences were observed between conditions for SR, SL, RPE, or La⁻, whereas peak HR was lower in the control. Although water did not significantly improve performance, swimmers reported more favourable sensations during the trial. In conclusion, the dryland protocol significantly improved 100 m freestyle performance, whereas the water protocol did not produce significant performance benefits under the present conditions. Full article

Understanding the interaction forces between climbers and climbing holds is important for motion analysis and performance evaluation in sport climbing. In particular, force measurement during speed climbing can provide valuable insights into explosive movements and athlete performance. However, many existing measurement systems require modifications to the climbing wall structure or sensors installed behind the wall, which limits their applicability to existing speed climbing facilities. This study proposes a wireless instrumented climbing hold for speed climbing that enables force-related measurement without modifying the wall structure. The proposed system integrates a six-axis force sensor, a microcomputer, a wireless communication module, and a battery inside the climbing hold. This self-contained configuration allows the hold to wirelessly transmit force and moment data during climbing while maintaining compatibility with standard speed climbing walls and competition environments. In addition, the system enables an estimation of the point of force application on the hold surface by combining measured force and moment data with the three-dimensional hold geometry. Experimental evaluations were conducted to verify the feasibility and performance of the system. External load tests using a digital force gauge confirmed that the embedded sensor can measure static loads and respond to rapidly changing loads with sufficient temporal responsiveness, and the estimated point of force application corresponded closely to the actual loading point. Furthermore, measurements on an actual speed climbing wall demonstrated that the proposed system can successfully capture interaction forces during climbing movements. These results indicate that the proposed system is a practical tool for force-based motion analysis in speed climbing. Full article

Background/Objectives: In the school setting, high-intensity interval training (HIIT) has emerged as a time-efficient strategy to improve children’s physical fitness; however, different implementation modalities have not been compared. The aim of this study was to compare the effects of an individual versus paired HIIT protocol based on functional bodyweight exercises on physical fitness-related and anthropometric outcomes in primary school children. Methods: Sixty-one children (11.6 ± 0.3 years) participated in a 10-week experimental study with three parallel groups: individual HIIT (EG1, n = 21), paired HIIT (EG2, n = 20), and a control group (CG, n = 20). Although both HIIT groups performed the same bodyweight functional exercises, in EG2 the exercises required coordinated movement between the partners. The HIIT protocol was integrated into the warm-up of Physical Education (PE) classes twice per week (Tabata-type protocol; 8 × 20 s/10 s/≤8 min per session). Body composition, muscular strength, and cardiorespiratory fitness (estimated VO₂max) were assessed at pre- and post-test, along with a rating of perceived exertion (1–10 scale) and enjoyment/motivation (1–5 scale) across several sessions (1, 7 and 14). Data were analyzed using pre-post comparisons, ANOVA, and ANCOVA models adjusted for baseline values. Results: Body fat percentage decreased in all groups. The individual HIIT group showed within-group improvements in VO₂max (+5.3%, p < 0.001), handgrip strength (+10.1%, p = 0.003), and standing long jump (+4.1%, p = 0.033), with moderate-to-large effect sizes, whereas the paired HIIT group showed smaller and statistically non-significant changes. Between-group comparisons suggested a tendency toward greater improvements in VO₂max and handgrip strength in the individual HIIT group compared with the paired group, although the overall ANOVA for VO₂max was not statistically significant. Perceived exertion declined over time in the paired group but remained relatively stable in the individual group. Conclusions: A low-volume HIIT program performed individually was associated with improvements in several physical fitness outcomes in schoolchildren. In contrast, paired execution showed smaller and mostly non-significant changes, together with a progressive reduction in perceived intensity. Full article

Elite women’s rugby has often been analysed using the male performance model as a reference, despite evidence that women’s rugby presents distinct game demands and potentially different risk profiles. This study aimed to compare the frequency of key contact-related events between elite men’s and women’s rugby. An observational, retrospective, comparative cohort study was conducted using official performance data from 135 international matches from the men’s and women’s Six Nations Championships. Variables were grouped into three categories: Open-Play, Static Phases, and Discipline. Independent samples t-tests, Mann–Whitney U tests, and Linear Discriminant Analysis were used to identify sex-based differences. The results showed that men presented a higher frequency of rucks lasting more than 6 s (p < 0.001), whereas no significant differences were found in total tackles (p = 0.378) or total rucks (p = 0.634). In Static Phases, women’s teams recorded significantly more scrums (p < 0.001). In Discipline, women conceded fewer free kicks (p = 0.003) but received more red cards (p = 0.020). In conclusion, elite women’s rugby shares some open-play characteristics with the men’s game but differs in scrum frequency and disciplinary profile, supporting the existence of a distinct contact and risk exposure profile that should be considered when designing training and prevention strategies. Full article

Objective: This study assessed the blood-pressure effects of various exercise regimens in middle-aged and older adults with type 2 diabetes, considering baseline levels, to clarify dose–response relationships for personalized exercise guidance. Methods: We conducted a dose–response network meta-analysis. Systematic searches were performed in Web of Science, EMBASE, PubMed and Cochrane Library. Baseline blood pressure was modelled as an explanatory variable via meta-regression. Thirty-six eligible RCTs of physical-activity interventions in older adults with type 2 diabetes reporting blood-pressure outcomes were included. Results: In stage 1–2 hypertension, mind–body activities were associated with the greatest systolic blood-pressure reduction and appear to be the most effective intervention based on available evidence. For diastolic blood pressure, combined aerobic-resistance training was effective in stage 1 hypertension. Dose–response analysis indicated that clinically meaningful reductions occur at modest volumes (668 and 657 MET-min/week for systolic and diastolic pressures, respectively), aligning with the lower end of international activity guidelines. Conclusions: Individualized exercise prescription based on baseline blood pressure may offer a useful non-pharmacological strategy for hypertension management in older adults with type 2 diabetes. By quantifying the required activity dose, this work provides an evidence base for integrating structured exercise into precision care for this high-risk population. Full article

Artificial intelligence (AI) is increasingly used in scientific research, including psychiatry. Exercise addiction (EA) research relies on self-report instruments, most of which lack a functional impairment criterion and cannot account for obsessive passion, potentially contributing to inflated prevalence estimates and limited clinical specificity. This study examined whether Claude AI (Sonnet 4.6) could assist in synthesizing a brief, theoretically grounded screening tool for EA by integrating validated constructs from the Passion Scale (PS), the Exercise Dependence Scale (EDS), and the Exercise Addiction Inventory (EAI). Using structured prompting and instrument upload, Claude AI created a 10-item scale by systematically mapping source-scale content onto established EA frameworks, including the components model and DSM-5 criteria. The instrument included nine Likert-type items and one binary gate for functional impairment to enhance clinical specificity. Although no empirical validation data were collected, a Monte Carlo simulation (N = 500) was used solely to verify that the prespecified unidimensional simulation model produced internally coherent response patterns. Because the simulated data were generated from and analyzed under the same unidimensional model, these results constitute a computational plausibility check rather than empirical structural validation. AI-assisted theoretical synthesis may offer a novel methodological approach to instrument development, though this remains a working hypothesis requiring empirical corroboration. The proposed Exercise Addiction Screening Scale (EASS-10) is presented as a proof-of-concept tool that now requires empirical validation in clinical and exercise populations. Full article