Medicine & Science in Sports & Exercise

This cross-sectional derivation and internal validation study aimed to develop and internally validate a clinical triage scoring system (CTSS) for field-based identification of collegiate athletes requiring priority intervention for lumbopelvic-hip (LPH) dysfunction. A total of 864 collegiate athletes (mean age 21.3 {+/-} 2.4 years; 80.8% male) were recruited from 10 universities. Participants underwent standardized assessments including demographic characteristics, clinical history, and LPH functional testing. Using an expert-adjudicated binary reference standard (priority intervention vs self-management), a multivariable logistic regression model was developed to derive the weighted CTSS. Model performance was evaluated using discrimination, calibration, and decision curve analysis (DCA), and internal validation was performed using 1,000 bootstrap resamples. Of the 864 participants, 463 athletes (53.6%) were classified as requiring priority intervention. The final 14-factor CTSS comprised 12 positive-weight predictors, such as localized LPH pain, muscle weakness, and higher body mass index, and 2 negative-weight predictors, positive Lasegues sign and hamstring weakness, which functioned served as safety-related modifiers. The model demonstrated acceptable discrimination (AUROC = 0.851, 95% CI: 0.824-0.876), with minimal optimism (optimism-corrected AUROC = 0.842) and excellent calibration (calibration slope = 1.000; calibration intercept = 0.000). A total score of [≥]9 was identified as the optimal threshold, yielding a sensitivity of 84.4% and specificity of 71.8%. DCA showed greater net benefit than treat-all and treat-none strategies across clinically relevant threshold probabilities (20%-50%), with a net benefit of 0.319 at a 50% threshold probability. The CTSS may provide a pragmatic field-based triage tool to support early identification of athletes who may require priority intervention, although external validation is needed before broader implementation in sports medicine settings.

The association between higher levels of physical activity and lower cancer risk and mortality is well established. However, a causal link is yet to be proven. Recent studies showed a decrease in the proliferation rates of cultured human cancer cells when the human serum employed to stimulate them was conditioned by acute exercise. Here, we tested the hypothesis that serum mediates some of the putative benefits of exercise on cancer through alterations to the growth pattern and susceptibility to chemotherapy agents of cancer cells. To this end, human non-small cell lung cancer (NSCLC) cells were exposed to serum from two cohorts that differed significantly on their levels of physical activity and, accordingly, cardiorespiratory fitness, but were otherwise identical (master athletes and non-exercisers), collected before and after an acute exercise intervention. Serum levels of glucose, lipids, albumin, C-reactive protein and cytokines were determined and the impact of the serum responses to acute and lifelong exercise on the above-mentioned parameters were analyzed. We found that acute exercise decreased the cells proliferation rate, yet shortened the cells lag phase after detachment, whereas lifelong exercise had the opposite effects. Significantly, we showed, for the first time, that lifelong exercise increased susceptibility to a chemotherapy agent (cisplatin), which may contribute to the decreased cancer mortality rates found among those who exercise regularly. Similar to the cellular effects, changes to serum cytokine levels - several of them linked to the senescence-associated secretory phenotype - depended on whether serum was conditioned by acute or by chronic exercise. Key pointsChronic exercise increased the in vitro susceptibility of lung cancer cells to cisplatin. Acute and chronic exercise modulated the in vitro tumorigenic potential of lung cancer cells. Effects were mediated by serological changes produced by exercise. Acute and chronic exercise had distinct impacts on serological cytokine levels.

ObjectiveTo investigate the effects of breaking up prolonged sedentary behavior (SB) on daily movement behavior and energy balance in adults with overweight/obesity. MethodsThirty participants (16F/14M; 34.2{+/-}7.3y; 29.5{+/-}3.2kg/m2) were randomized to either BREAK (nine hourly 5-min brisk walking bouts) or a duration-matched intervention, ONE (45-min brisk walking), both performed 5 days/week for 6 weeks. Pre- and post-intervention, daily SB and physical activity (PA; accelerometry), body composition (doubly labeled water [DLW]), total daily energy expenditure (TDEE; DLW), appetite, and fasting leptin were measured. Linear-mixed effects models tested time effects and time-by-group interactions. ResultsOnly BREAK reduced prolonged SB (-8%; interaction: p=0.043). Both groups shifted SB-PA composition toward greater moderate-to-vigorous PA with proportional reductions in SB and light PA (time: all p[≤]0.011), which were associated with increases in TDEE (+0.67 MJ/d; time: p=0.040). Body and fat mass increased in ONE only (interaction: p=0.061 and p=0.055). No differences were noted in energy intake, appetite, or leptin levels. ConclusionsSpreading short PA bouts throughout the day increases MVPA and TDEE to the same extent as a traditional continuous PA bout. Future studies should investigate whether minor differences in body composition are driven by distinct behavioral/physiological compensations influenced by the daily pattern of PA/SB. STUDY IMPORTANCE QUESTIONSO_LIWhat is already known about this subject? O_LIAcutely, breaking up prolonged sedentary behavior (SB) with short bouts of physical activity (PA) increases energy expenditure and reduces food cravings compared to a single continuous PA bout. C_LIO_LISingle continuous PA bouts have been associated with compensatory reductions in non-exercise activities (daily living activities) in some studies, which may attenuate increases in total daily energy expenditure (TDEE) and limit effects on body mass and adiposity. C_LI C_LIO_LIWhat are the new findings in your manuscript? O_LIPerforming brisk walking either through frequent, short bouts spread across the day or as a single continuous bout over 6 weeks increases moderate-to-vigorous PA (MVPA) at the expense of SB and light PA and increases TDEE to a similar extent in adults with overweight or obesity. C_LIO_LIHowever, only the frequent, short active breaks reduced time spent in prolonged SB (>60 min), an independent cardiometabolic health risk factor. C_LIO_LIDespite no differences in energy intake, appetite, or plasma leptin concentration, the single continuous bouts were associated with a small, non-robust increase in body and fat mass, whereas these remained stable in the active breaks group, suggesting differential compensatory adaptations. C_LI C_LIO_LIHow might your results change the direction of research or the focus of clinical practice? O_LIPromoting frequent, short bouts of PA throughout the day can improve daily movement and help meet current PA/SB guidelines to a similar extent as traditional PA strategies, while also reducing prolonged sedentary time. C_LIO_LIThis strategy may help limit compensatory responses sometimes observed in response to continuous MVPA bouts, offering a new tool to manage body weight. C_LIO_LIHowever, differences in body composition outcomes were small and not robust, and future studies are needed to determine whether these patterns translate into meaningful long-term effects on energy balance and weight regulation. C_LI C_LI

ObjectivesTo determine whether early functional severity at presentation explains variability in return to sport (RTS) after ankle sprain in young athletes, compared with sprain subtype and injury mechanism. DesignRetrospective cohort study. MethodsAthletes aged [&le;]22 years with acute ankle sprains were identified from a prospectively maintained institutional database. Surgically treated cases were excluded. Functional severity at presentation was classified into three grades based on the ability to continue sports participation and ambulate immediately after injury. Injury mechanisms were categorized as high-energy deceleration (HED) or non-HED. RTS was analyzed as time to return and as prolonged RTS ([&ge;]4 weeks). Multivariable logistic regression was performed to identify factors independently associated with prolonged RTS. ResultsA total of 437 cases were included. Median RTS was 2.0 weeks (interquartile range, 0.0-4.0), and prolonged RTS occurred in 33.0% of cases. RTS duration increased stepwise with greater functional severity (p < 0.001). In multivariable analysis, functional severity was strongly associated with prolonged RTS (Grade 2: adjusted odds ratio [OR], 3.58; 95% confidence interval [CI], 2.07-6.19; Grade 3: adjusted OR, 24.53; 95% CI, 10.67-56.43; p < 0.001), and age was also independently associated (adjusted OR, 1.19 per year; 95% CI, 1.11-1.27; p < 0.001). Sprain subtype and injury mechanism were not independently associated with RTS after adjustment. ConclusionsEarly functional severity at presentation is the primary determinant of RTS after ankle sprain in young athletes. Apparent differences related to sprain subtype and injury mechanism are largely explained by initial functional impairment.

ObjectiveTo develop and internally validate a field-side triage model to support early specialist referral decisions in young athletes with acute lower extremity sports injuries, where diagnostic resources are often limited. DesignRetrospective cohort study. SettingSingle-center sports medicine clinic. ParticipantsAthletes aged [&le;]22 years presenting with acute lower extremity sports injuries between January 2017 and November 2025. Independent VariablesAge, sex, functional severity, injury site, and injury mechanism assessed at initial presentation. ResultsA total of 2,129 athletes were included, with 276 (13.0%) undergoing surgery. Independent predictors were older age, female sex, greater functional severity, knee involvement, and high-energy deceleration mechanisms. The full model showed good performance (AUC 0.890; Brier score 0.073; calibration slope 1.00), and the simplified model also demonstrated high discrimination (AUC 0.883). Risk stratification showed increasing surgical rates across low-, intermediate-, and high-risk groups. Decision curve analysis demonstrated greater net benefit than treat-all and treat-none strategies across clinically relevant thresholds. ConclusionsA field-side prediction model based on readily obtainable clinical variables demonstrated good performance for identifying young athletes at risk of requiring surgical intervention and may support early specialist referral decisions in resource-limited settings. Clinical RelevanceThis model provides a practical tool for early risk stratification using simple clinical information, supporting timely and appropriate referral decisions in field-side and initial clinical settings.

This study examined the utility of HRV detrended fluctuation analysis alpha-1 (DFA1) to assess readiness-to-train and exercise durability under varying acute training loads. Nineteen trained cyclists completed two 20-minute time-trials (TT) under rested and fatigued conditions. DFA1 was measured during a standardized warm-up (WU), 20-min TT, and standardized cool-down (CD). Power output (PO) and DFA1 responses were compared across conditions, and associations with performance and fitness (W/kg) were examined. DFA1 values declined with increasing WU and CD exercise intensity (p<0.001) and were significantly attenuated following the 20-min TT (p<0.001). While DFA1 profiles did not differ significantly between rested and fatigued conditions, lower pre-TT DFA1 was associated with reduced TT performance (p=0.022; r=0.55), suggesting relevance to training readiness. Additionally, an 18% decline in DFA1 between 10- and 20-min during the TT (p=0.031), and lower post-TT values at matched intensities were observed (p<0.001), indicating physiological perturbation from the 20-min TT. Fitter participants exhibited lower DFA1 values during the 20-min TT (p<0.001; r=-0.77), suggesting a greater capacity to sustain physiological stress. While DFA1 is responsive to exercise intensity and stress, offering potential to assess training readiness and durability, more robust fatigue protocols are needed to validate DFA1 as training load monitoring tool.

New FindingsWhat is the central question of this study? Are adaptations elicited by combined flywheel resistance and aerobic exercise influenced by habitual physical activity levels in patients with chronic kidney disease? What is the main finding and its importance? Combined flywheel resistance and aerobic exercise promote clinically meaningful improvements in muscle size, power output, and physical function in patients with chronic kidney disease. Those not meeting the weekly moderate intensity physical activity recommendations experienced greater increases in power output compared to those who were physically active whereas no differences in the magnitude of improvements in physical function were observed between physical activity levels. Physical inactivity is common in chronic kidney disease (CKD) and is associated with poor neuromuscular and functional outcomes. Whether habitual physical activity (PA) influences adaptations to structured exercise in CKD remains unclear. This study examined if adaptations to combined flywheel resistance and aerobic exercise (FRE+AE) differed based on self-reported PA in Veterans with CKD stages 3-4. Twenty older male Veterans with CKD stages 3-4 (mean eGFR 37.9 {+/-} 10.2 mL/min/1.73 m{superscript 2}) were randomized to six weeks of FRE+AE (n=11) or health education (EDU; n=9). Participants were classified as meeting (Meets PA) or below (Low PA) weekly moderate intensity PA recommendations using the 7-day Physical Activity Recall. Outcomes included vastus lateralis muscle thickness (VL MT), knee extensor power output (60{degrees}{middle dot}s-1 and 180{degrees}{middle dot}s-1), gait speed (GS), and five-repetition sit-to-stand (STS). FRE+AE increased VL MT (p=0.030), power output at 180{degrees}/s (p=0.021), GS (p=0.001), and reduced STS time (p=0.012), with significant between-group differences versus EDU for VL MT (p=0.009) and GS (p=0.028). Low PA experienced greater increases in power output at 60{degrees}{middle dot}s-1 (Hedges g; Low PA=0.44, Meets PA=0.25) and 180{degrees}{middle dot}s-1 (Hedges g; Low PA=1.38, Meets PA=0.38) compared to Meets PA after FRE+AE. Conversely, Meets PA had greater improvements in GS (Hedges g; Low PA=0.93, Meets PA=1.29) and STS (Hedges g; Low PA=-0.72, Meets PA=-2.20) compared to Low PA. Six weeks of FRE+AE produced clinically meaningful neuromuscular and functional improvements in Veterans with CKD stages 3-4 irrespective of PA level, supporting FRE+AE as a feasible intervention in this population.

Objective: To examine the joint associations of cardiorespiratory fitness (CRF) and polygenic risk with incident breast cancer and whether higher CRF attenuates excess breast cancer risk associated with high polygenic risk in postmenopausal women. Methods: This prospective cohort study included postmenopausal women from the UK Biobank. CRF was estimated using a submaximal cycle ergometer test, and genetic susceptibility was assessed using a breast cancer polygenic risk score (PRS). Associations of CRF and PRS with incident breast cancer were examined using Cox proportional hazards models with age as the underlying time scale. Analyses were conducted overall and stratified by age (40-59 and [&ge;]60 years) and body mass index (BMI) (<25 and [&ge;]25 kg/m2). Multiplicative and additive interactions were evaluated, with additive interaction assessed using the relative excess risk due to interaction (RERI). Results: During a median follow-up of 10.7 years, 500 incident breast cancer cases were identified among 13,907 postmenopausal women. Higher CRF was associated with a lower breast cancer risk in a dose-response manner. Although multiplicative interaction was not significant, higher CRF attenuated excess risk associated with high polygenic risk on the additive scale (RERI -0.84, 95% CI -1.56 to -0.12). This attenuation was particularly evident among women aged [&ge;]60 years and those with BMI [&ge;]25 kg/m2. Conclusion: Higher CRF was associated with a lower breast cancer risk and attenuated excess breast cancer risk associated with high polygenic risk, particularly among postmenopausal women at elevated baseline risk, supporting a potential role for improving CRF in genetically informed breast cancer prevention.

Background: Individuals with coronary artery disease (CAD) are at higher risk of cognitive decline and dementia, in which gray matter cerebral blood flow (CBF) plays a critical role. This study investigated the effects of High Intensity Interval Training (HIIT) and HIIT plus resistance training (RT) on CBF and other health outcomes in individuals with CAD. Methods: This trial included 105 participants with CAD (age 62.1 (SD 6.6) years, 21% women) randomly assigned to HIIT+RT (n=37), HIIT (n=35) or usual care (n=33). The primary outcome was the change in global CBF from baseline to 12-week follow-up. Secondary outcomes included: region-specific CBF (hippocampus, precuneus, and anterior/posterior cingulate cortex), cognitive function (general cognition, episodic memory, processing speed, working memory and executive function/attentional control), peak oxygen uptake (VO2peak), muscular fitness (30s sit-to-stand) and body composition [weight, body mass index (BMI), and fat and muscle mass). Data were analyzed using available-case intention-to-treat constrained (baseline-adjusted) linear mixed models. Predefined subgroup analyses were conducted for age, sex, education, and baseline level of the outcome studied. Results: No significant between-group differences were observed in CBF changes in the whole sample. However, participants with lower CBF at baseline showed greater CBF increases in the HIIT group compared to both usual care (+7.1 ml/100g/min, P=0.02) and HIIT+RT (+5.53 ml/100g/min, P=0.04). No effects were observed on regional CBF or cognition. Both exercise groups improved VO2peak compared to usual care (HIIT+RT: +2.6; HIIT: +2.5 mL/kg/min, both P<0.001). Only HIIT+RT increased muscular fitness (vs usual care: +3.3; vs HIIT: +3.1 repetitions, both P<0.001), and only HIIT decreased BMI (vs usual care: -0.47; vs HIIT+RT: -0.44 kg/m2, both P<0.03). No life-threatening events or deaths occurred during 1995 training sessions in the exercise groups, nor in the usual care group. Conclusion: Twelve weeks of HIIT+RT or HIIT did not increase CBF in the whole sample with CAD, but HIIT effectively increased CBF in those who had poorer CBF at baseline. While no cognitive benefits were observed, we found exercise-specific improvements in other clinically relevant outcomes, such as VO2peak, muscular fitness, and BMI.

The transition to higher education is characterized by increased academic demands and psychosocial stress, which may negatively affect cognitive functioning and student well-being. Executive functions (working memory, inhibitory control, and cognitive flexibility) are critical for academic adaptation and can be enhanced through structured interventions. Physical exercise, mind-body practices, and cognitive training have demonstrated potential benefits for executive functioning and stress reduction; however, few randomized controlled trials have directly compared interventions with different physical and cognitive demands in university students, particularly in Latin America. In addition, most studies have relied on self-report measures and physiological stress biomarkers such as salivary cortisol. This protocol describes a three-arm, parallel-group randomized controlled trial designed to evaluate the effects of a 12-week intervention on executive functions and stress in first-year university students. The study will recruit 120 first-year health-science students aged 18-25 years. Participants will be randomly assigned (1:1:1), using block randomization stratified by sex, to one of three interventions delivered twice weekly (24 sessions of 60 minutes): (1) moderate-to-vigorous motor-cognitive dual-task exercise (DT); (2) low-to-moderate intensity Tai Chi (TC); or (3) supervised digital cognitive stimulation (CS) using structured graphomotor tasks. Primary outcomes include executive functions assessed through standardized neuropsychological measures. Secondary outcomes include stress will be evaluated using the Academic Stress Inventory, Depression Anxiety Stress Scales and salivary cortisol collected in the morning using passive drool and analyzed by competitive ELISA.Other outcomes include physical activity levels, anthropometric and body composition measures, and handgrip strength. Data will be analyzed following an intention-to-treat approach using repeated-measures models, with multiple imputation for missing data. The study has received institutional ethics and biosafety approval. Trial registration: ClinicalTrials.gov Identifier: NCT07443904.

ObjectivesThis study aimed to compare exercise-induced changes in serum and salivary concentrations of cardiac troponin-I (cTnI) in athletes during and after a marathon. MethodsThirty-six male runners were recruited. Eighteen participants in group 1 completed a marathon (42.195 km), while eighteen participants in group 2 did not undergo this exercise. Blood and saliva samples were collected at twelve different time points and then analyzed for cTnI using an immunoassay. ResultsBiphasic cTnI release into the circulation was observed during and after the marathon. Moreover, a similar pattern of biphasic cTnI elevation was found in saliva. In group 1, salivary and serum concentrations of cTnI first peaked after 60 min of exercise (0.67{+/-}0.08 ng/mL and 0.76{+/-}0.07 ng/mL), decreased slightly towards the end of the marathon (0.40{+/-}0.06 ng/mL and 0.46{+/-}0.06 ng/mL), and then reached a second, higher peak 4 h post-exercise (0.72{+/-}0.09 ng/mL and 0.82{+/-}0.09 ng/mL), returning to baseline by 48 h after marathon completion (0.16{+/-}0.04 ng/mL and 0.18{+/-}0.04 ng/mL). In group 2, there were no time-dependent changes in cTnI concentrations in both saliva and serum. Deming regression and Passing-Bablok regression demonstrated that there was proportional agreement between salivary and serum levels of cTnI in both groups at all twelve time points. The Bland-Altman method revealed that there was a negative differential bias but no proportional bias in the data. ConclusionsDocumenting a similar, biphasic pattern of cTnI elevations in saliva and serum during and after the marathon provides a reliable non-invasive alternative without requiring a blood draw.

ObjectivesTo investigate the epidemiology of acute sports-related upper-extremity injuries in young athletes, with a particular focus on the frequency, anatomical distribution, injury types, and mechanisms of digit injuries. MethodsThis single-center retrospective observational study included athletes aged [&le;]22 years who sustained acute sports-related upper-extremity injuries between January 2017 and November 2025. Digit injuries were defined as injuries involving the thumb and fingers at or distal to the metacarpophalangeal joint. Injury characteristics, mechanisms, and sports categories were analyzed using descriptive statistics. ResultsA total of 1,219 acute sports-related upper-extremity injuries were analyzed. Digit injuries were the most common injury location, accounting for 412 cases (33.8%), followed by shoulder (30.7%), elbow (17.5%), wrist (14.4%), and palm injuries (3.6%). Jammed finger was the most frequent injury type, comprising 64.8% of digit injuries, followed by fractures (20.1%) and dislocations (5.3%). Most injuries were caused by contact mechanisms (90.3%), with ball contact being the predominant cause (49.5%). Ball sports accounted for 85.4% of all digit injuries. ConclusionsDigit injuries represent the most frequent acute sports-related upper-extremity injuries in athletes aged [&le;]22 years, with jammed finger accounting for the majority of cases. Most injuries were associated with ball contact, highlighting the need for preventive strategies and appropriate initial management for digit injuries in young athletes.

Background: Exercise-based cardiac rehabilitation (CR) improves peak oxygen uptake ([V]O2peak) in patients with coronary heart disease (CHD); however, whether women and men exhibit similar adaptations across the steps of O2 transport remains unknown. We aimed to compare the ventilatory and circulatory determinants of [V]O2peak changes between women and men with CHD following a structured exercise training program. Methods: A total of 28 women (27%) and 75 men (73%) with CHD, matched for age, body mass index, and [V]O2peak (% predicted), underwent maximal cardiopulmonary exercise testing (CPET) before and after 12 weeks of CR. [V]O2peak and minute ventilation ([V]E) were measured breath by breath. Heart rate and cardiac output ([Q]c)were assessed non-invasively using impedance cardiography. Exercise efficiency ({Delta}[V]O2/{Delta}W), alveolar ventilation ([V]A), ventilatory efficiency (OUES), O2 pulse, arteriovenous oxygen content difference (C(a-[v])O2) and gross muscular efficiency (W) were calculated using standard equations. Mixed model analyses (sex x time) were used to compare training-induced changes between sexes. Results: At baseline, values of [V]O2peak (absolute and normalized by fat free mass), [V]E, [V]A, O2 pulse, C(a-[v])O2, {Delta}[V]O2/{Delta}W, W were significantly lower in women than in men with CHD (group effect, p<0.01). [V]O2peak normalized by fat-free mass improved similarly in both sexes after CR (p<0.0001, no significant sex x time interaction). Pulmonary convection ([V]E, [V]A), ventilatory efficiency (OUES), circulatory convection ([Q]c, cardiac index, O2 pulse), and peripheral gross muscular efficiency (W) all improved similarly after CR in women and men (effect sizeXtime effect, p<0.05, no significant group x time interaction). The prevalence of responder categories did not differ between sexes (p=0.826). Conclusion: Women and men with CHD demonstrated equivalent O2 transport phenotype adaptations after CR, with comparable improvements across the O2 transport chain (pulmonary, circulatory, and peripheral determinants of [V]O2peak).

BackgroundCardiovascular disease (CVD) prevention is limited by the major challenge of low long-term adherence to effective lifestyle regimens. Arterial stiffness (measured by carotid-femoral pulse wave velocity, cfPWV) and maximal cardiorespiratory fitness (measured by VO2max), are modifiable risk factors for CVD but require sustained lifestyle change. Wearable technology provides continuous measurement and offers a scalable platform to deliver health interventions. A combination of continuous monitoring with a wearable device and an artificial intelligence (AI) -based coach personalized for individual data and preferences could be a powerful, low-barrier tool for achieving sustainable cardiovascular health benefits by directly addressing the adherence challenge. ObjectiveWe will study the comparative effectiveness of a wearable and an interactive app-based AI coaching intervention promoting moderate exercise on improving gold-standard cfPWV and VO2max. This will be compared to a supervised high-intensity interval training (HIIT) group (benchmark with known benefits for VO2max) and a control group using only Oura Ring (passive monitoring). We will also conduct a detailed Process Evaluation (structured interviews) to study the feasibility and experience of interacting with the AI coach. MethodsThis randomized controlled trial recruited 165 eligible sedentary participants aged 30-65 years. Co-primary outcomes cfPWV and VO2max were measured at baseline and will be repeated after 12 weeks. Participants were equally randomized into three groups: an AI-based coaching group (steady-state exercise), a HIIT group (supervised exercise) and a control group (usual low activity). The AI-based coaching group receives personalized guidance using large language model (LLM) technology. All participants wear Oura Ring and are blinded to cardiovascular health metrics provided by the ring. ResultsThe recruitment for the study began in October 2024 and will end when 165 men and women have been recruited. Data collection for the study is scheduled to conclude early 2026. Data collection is ongoing. ConclusionsThis study will evaluate if a highly scalable, AI-based coaching intervention can achieve comparable gains in CV structural health (cfPWV) and functional capacity VO2max relative to a resource-intensive supervised HIIT benchmark. The findings will provide essential evidence on the use of digital health tools to promote sustainable exercise adherence. ClinicalTrials.gov registration identifierNCT06644014 (Registered: 2024-10-15)

Background: Quadriceps strength and landing mechanics are two modifiable factors associated with anterior cruciate ligament (ACL) injury risk. Collecting detailed biomechanical data is an arduous task. Identifying a relationship using more easily measured variables, such as quadriceps strength, would offer value for athlete counseling and injury prevention programs. Although quadriceps weakness has been associated with altered landing strategies in ACL-reconstructed (ACLR) individuals, this relationship is less clear in healthy athletes. Purpose: To investigate the association between isokinetic quadriceps strength and peak knee flexion angle during a vertical drop jump in healthy adolescent athletes. Study Design: Secondary analysis of previously collected data. Methods: Healthy adolescent athletes had their dominant leg quadriceps strength measured using an isokinetic dynamometer at 60{degrees}/s from 0-90{degrees} of knee flexion. Landing mechanics were assessed during a vertical drop jump using three-dimensional motion capture synchronized with force plates. Pearson correlation was used to evaluate the association between quadriceps strength and peak knee flexion angle during landing, with statistical significance defined as p < .05. Results: There was a weak negative correlation between quadriceps strength and peak knee flexion angle (p = .017, R = -.22 [-.04, -.38]), suggesting that stronger athletes achieved greater knee flexion angles. Discussion: Greater quadriceps strength was associated with increased peak knee flexion angles during landing; however, the weak correlation suggests that strength explains only a small portion of the variability in landing mechanics. These findings deviate slightly from prior literature in healthy populations but are consistent with studies demonstrating that greater quadriceps strength is associated with achieving greater peak knee flexion in ACLR patients. Accordingly, quadriceps strengthening should remain a key component of multifactorial ACL injury prevention programs.

Background: This prospective cohort analysis investigated how age, sex, and body morphology modify associations of physical activity (PA) intensity, duration, and volume with cardiovascular disease (CVD) mortality. Methods: We analysed wrist-worn accelerometer data from 8,661 adults (51.9% women) in the National Health and Nutrition Examination Survey. The outcome was CVD mortality. PA intensity and volume were quantified using the intensity gradient and average acceleration, respectively. Survey-weighted Cox proportional hazards models were used to estimate associations, including interaction terms with age, sex, or body morphology (waist-to-height ratio as indicator of adiposity). Results: Median (interquartile range) follow-up was 81 (69, 94) months. All hazard ratios (HR) compare 50th with 25th percentile. Beneficial associations between CVD mortality and PA were stronger in younger than older adults for intensity (e.g., 45-year-olds: HR=0.47, 95%CI:0.29-0.75 vs 75-year-olds: HR=0.75, 95%CI:0.54-1.06), and volume (e.g., HR=0.18, 95%CI:0.07-0.71 vs 0.29, 95%CI:0.16-0.51). In women, intensity-related association were stronger than in men (HR=0.45, 95%CI:0.31-0.65 vs HR=0.79, 95%CI:0.50-1.24). Volume-related associations were stronger in men (HR=0.37, 95%CI:0.22-0.60 vs HR=0.24, 95%CI:0.11-0.51), though with earlier plateauing and greater uncertainty. Associations were observed across waist-to-height ratio levels but attenuated at higher values (intensity: waist-to-height ratio 0.5, HR=0.45, 95%CI:0.29-0.69 vs 0.6, HR=0.69, 95%CI:0.49-0.97; volume: 0.5, HR=0.07, 95%CI:0.03-0.17 vs 0.6, HR=0.28, 95%CI:0.17-0.45). Conclusion: Older adults and men may benefit more from increasing PA volume than intensity, whereas younger adults and women may benefit more from higher-intensity PA. Although benefits were observed across adiposity levels, associations were attenuated as adiposity increased, suggesting stronger benefits in individuals with low-to-moderate adiposity.

Background. Obesity is a modifiable risk factor for osteoarthritis and may contribute to pain, functional impairment, inflammation, and cartilage degradation. Resveratrol has potential anti-inflammatory and chondroprotective effects, but its efficacy as an adjunct to dietary intervention remains unclear. Objective. This study evaluated whether resveratrol supplementation provides additional benefits when combined with a low-calorie diet in postmenopausal women with obesity and knee osteoarthritis. Methods. A total of 97 postmenopausal women with obesity and knee osteoarthritis were included in this randomized controlled clinical study. Participants received either a 10-day low-calorie diet alone or the same diet combined with 150 mg/day trans-resveratrol. Anthropometric parameters, body composition, biochemical markers, pain intensity, functional status, and urinary CTX-II were assessed at baseline and follow-up. Results. Both interventions were associated with reductions in body weight, BMI, waist and hip circumferences, fat mass, glucose, HOMA-IR, lipid parameters, hsCRP, VAS, WOMAC, LAI, and urinary CTX-II. Compared with diet alone, resveratrol supplementation did not provide additional benefits for anthropometric parameters, glucose metabolism, lipid profile, or WOMAC score. However, the resveratrol group showed a greater reduction in hsCRP and urinary CTX-II. The obesity class did not modify the treatment effect. Conclusion. A short-term low-calorie diet improved metabolic, inflammatory, and osteoarthritis-related parameters in postmenopausal women with obesity and knee osteoarthritis. The addition of resveratrol did not enhance weight loss or improve most metabolic outcomes but was associated with greater reductions in hsCRP and urinary CTX-II. These findings suggest a potential anti-inflammatory and cartilage-related effect of resveratrol, which requires confirmation in longer randomized trials.

Objectives To examine the acute effects of a single bout of high-intensity interval training (HIIT) on fetal blood flow distribution during the third trimester of pregnancy. Methods Thirty-four healthy pregnant participants (mean age 31.6 years, standard deviation (SD) 4.1; gestational week 33.8 (SD 0.4) completed eight 30-second high-intensity cycling work-bouts interspersed with 2-minute rest periods. Fetal heart rate (FHR), maternal blood pressure, and Doppler-derived blood flow indices in the middle cerebral artery, umbilical artery and vein, and ductus venosus were assessed before and after exercise. We estimated fetal liver blood flow and the ratio of umbilical vein flow to ductus venosus. Maternal heart rate (HR) and FHR were recorded throughout exercise. Paired t-tests compared pre- and post-exercise values. Results No significant changes were observed in fetal blood flow indices or distribution following exercise. Average maternal HR and FHR during the work-bouts were 158 bpm (SD 16) and 152 bpm (SD 12), respectively. Following HIIT, maternal systolic blood pressure increased by 5 mmHg (95% CI 1 to 8, p=.014), maternal HR by 22 bpm (95% CI 15 to 28, p<.001), and FHR by 13 bpm (95% CI 10 to 17, p<.001). We recorded 16 instances of FHR above normal range during HIIT. Conclusion A single HIIT session in late pregnancy increased maternal blood pressure and HR and transiently elevated FHR but did not affect fetal blood flow indices or distribution. Brief episodes of fetal tachycardia were observed but appeared to be clinically insignificant. Future research should investigate the effects of repeated HIIT exposure during pregnancy.

BackgroundPatients who have undergone Anterior Cruciate Ligament Reconstruction (ACLR) have a 6-24% chance of either re-tearing or having subsequent knee surgery. To date there have been no practical validated risk prediction models that can be easily implemented into clinical workflow for re-injury risk. Micro-Doppler radar (MDR) provides a promising solution. ObjectiveThe purpose of this study was to investigate the predictive ability of MDR to identify persons with a previous ACLR relative to an age and sex matched healthy control. MethodsACLR patients (n=81) and controls (n=100) performed drop box jump, sit to stand (STS), and walking trials as MDR signatures were collected. A 1D Convolutional Neural Network was developed to evaluate each activity individually followed by the development of a fusion model validation using all three activities. ResultsThe STS model individually achieved the highest overall accuracy of 82.3%, with a sensitivity of 71.6% and specificity of 91.0%. The fusion model using all activities achieved a peak overall accuracy to detect ACLR of 86.2%, 80.3% sensitivity, and 91% specificity. ConclusionsCurrently, there is no clinically validated, efficient approach to objectively evaluate human motion at the point of care. When coupled with machine learning, MDR accurately differentiates ACLR from control groups by identifying complex biomechanical asymmetries, with classification performance comparable to or exceeding that of motion capture. Future research is needed to determine if MDR can be used in conjunction with risk prediction modeling. Key pointsMicro-Doppler radar provides a promising new solution to identify important human motion asymmetries in clinical settings. Here we evaluated a group of patients who have a history of Anterior Cruciate Ligament reconstruction versus a control group. Simple movements performed in the presence of the micro-Doppler radar system were used to identify the 2 groups with accuracy comparable or superior to motion capture systems.

BACKGROUND: Dual task walking requires simultaneous management of cognitive and motor demands and is associated with changes in gait and cortical activation. However, the relationship between task related cortical recruitment and dual task related gait adjustments in healthy young adults remains unclear. This study aimed to investigate the effects of dual tasking on gait performance and cortical activation, and to examine the association between changes in cortical activity and dual-task costs. METHODS: This cross sectional study included 33 healthy young adults. Participants performed three conditions: single task walking, cognitive single task (verbal fluency), and dual task walking. Each condition was repeated 10 times using a repeated short block design with randomized trial presentation. Gait performance was assessed using an instrumented walkway, and cortical activation was measured using functional near infrared spectroscopy. Dual task costs were calculated for gait and cognitive outcomes. Statistical analysis included repeated measures analysis of variance (ANOVA) and Wilcoxon signed rank tests, with false discovery rate correction for multiple comparisons. Associations between changes in cortical activation and dual task costs were examined using correlation analyses. RESULTS: Dual task walking resulted in significant changes in gait, including reduced speed, step and stride length, and increased base of support, stance, and double support (all p < 0.05), while cognitive performance remained unchanged. Dual tasking was associated with increased cortical activation in left prefrontal and motor related regions. Greater increases in cortical activation were associated with lower dual task costs across most gait parameters, with significant correlations observed in the left dorsolateral prefrontal cortex (r {approx} 0.42 to 0.47 for speed and stride length; p < 0.05). Double support showed a distinct pattern, suggesting a specific temporal adjustment within the gait cycle. CONCLUSIONS: Dual task walking in young adults is associated with coordinated behavioral and cortical adaptations. Increased cortical recruitment is linked to reduced motor interference, suggesting that broader engagement of cortical networks may contribute to performance under cognitive motor load.