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PubMed2026

Using the OPTIMAL Theory to Optimize Aerodynamics in Respiratory Training for Healthy Adults and Individuals With Parkinson's Disease.

BACKGROUND: The OPTIMAL (Optimizing Performance Through Intrinsic Motivation and Attention for Learning) theory is a motor learning framework proposing that optimizing intrinsic motivation enhances motor performance and learning. The theory identifies three key components-Enhanced Expectancies (EE), Autonomy Support (AS) and External Focus of Attention (EF)-which facilitate more efficient, goal-directed movement. These components have been shown to improve motor outcomes in limb-based tasks; however, their application to respiratory training, particularly in clinical contexts such as voice and swallowing therapy in patients with Parkinson's disease (pwPD), has not yet been systematically explored. AIMS: This study aimed to investigate whether implementing OPTIMAL theory strategies during a respiratory muscle strength training (RMST) task improves immediate respiratory motor performance in healthy adults and pwPD. Additionally, we aimed to examine the effects of these strategies on motivation and cognitive engagement. METHODS: This quasi-randomized, single-session trial included 47 participants: Healthy CONTROL (n = 17), Healthy OPTIMAL (n = 16) and PD OPTIMAL (n = 14). Healthy participants were quasi-randomly assigned to either intervention or control conditions, whereas pwPD completed the intervention only. All participants completed a single respiratory session that included baseline, practice and retention phases. Outcome measures included peak expiratory flow, cough peak expiratory flow, cognitive engagement (EEG-based Cognitive Engagement Index) and self-administered motivation questionnaire. OUTCOMES AND RESULTS: Exhalation force improved from baseline to retention in the Healthy OPTIMAL group (baseline: M = 296 L/min; retention: M = 338 L/min; p < 0.001) and the PD OPTIMAL group (baseline: M = 315 L/min; retention: M = 370 L/min; p < 0.0001), but not in the Healthy CONTROL group (p > 0.05). No significant changes in cough strength were observed in any group. No correlations were found between cognitive engagement and exhalation force or motivation scores. However, motivation increased more in the Healthy OPTIMAL group (Questionnaire 1: M = 57.2; Questionnaire 2: M = 60.7) and the PD OPTIMAL group (Questionnaire 1: M = 60.1; Questionnaire 2: M = 62.8) than in the Healthy CONTROL group (Questionnaire 1: M = 61.1; Questionnaire 2: M = 62.5). CONCLUSIONS AND IMPLICATIONS: Implementing the OPTIMAL theory enhances immediate respiratory motor performance in both healthy participants and pwPD. OPTIMAL theory has clinical value in voice and swallowing therapy, although further research is needed to establish long-term efficacy and clinical impact. WHAT THIS PAPER ADDS: What is already known on the subject Motivation is a critical factor in rehabilitation. The OPTIMAL theory has been shown to improve both motivation and motor performance in limb-based tasks. Its impact on respiratory training, however, has not been previously examined. What this paper adds to the existing knowledge This study shows that applying OPTIMAL strategies during a respiratory muscle strength training task significantly improved peak expiratory flow in both healthy adults and people with Parkinson's disease. What are the potential or clinical implications of this work? Integrating the OPTIMAL theory principles into respiratory therapy may enhance motor outcomes, supporting voice, swallowing and cough rehabilitation.

Humans↗

PubMed2026

Influence of Repeated-Sprint Bout Duration in Sprint Interval Training Intervention on Physical Performance Adaptations of Young Volleyball Players.

The objective of this study was to examine the effects of repeated-sprint training (RST) with varying bout durations on the physical fitness adaptations of young male volleyball players. Forty athletes were randomly allocated to one of three intervention groups performing RST with varying bout durations and similar repetition volumes, all executed at maximal effort. The 3-sec group (n = 10) completed two sets of 30 bouts, the 6-sec group (n = 10) performed two sets of 15 bouts, and the 9-sec group (n = 10) carried out two sets of 10 bouts, each adhering to a 1:3 work to rest ratio. An active control group (n = 10) engaged solely in regular volleyball training without the RST intervention. Physical fitness measures-including countermovement vertical jump (CMVJ), 10-m and 20-m linear sprints, T-test change-of-direction speed (T-CODS), reactive strength index (RSI), and the Wingate anaerobic power test-were assessed pre- and post-a 6-week training intervention (i.e., 18 sessions). All RST groups showed significant post-intervention improvements in physical fitness (main effect of time, p = 0.001), with greater adaptations compared with the control group and effect sizes ranging from small to very large. The 3-sec bout group demonstrated greater gains in CMVJ, 10-m and 20-m sprint performance, RSI, and peak power output compared with the 9-sec group (all, p < 0.05). Conversely, the 9-sec group exhibited superior adaptations in T-CODS and mean power output relative to the 3-sec group (all, p < 0.05). In conclusion, the 3-sec group experienced greater enhancements in explosive and sprint performances, while the 9-sec group showed superior gains in change of direction and mean power output. These findings indicate that manipulation of sprint-bout duration in RST can be used to optimize distinct performance adaptations in young volleyball players.

Humans↗

PubMed2026

Exercise prehabilitation in head and neck cancer patients proposed for definitive chemoradiotherapy: The FIT4TREAT randomized controlled trial.

BACKGROUND: Patients with head and neck cancer (HNC) initially scheduled for definitive chemoradiotherapy (CRT) often experience early functional decline and deterioration in health-related quality of life (HRQoL) even before treatment initiation. Evidence for prehabilitation in this non-surgical setting remains limited. This study evaluated whether exercise prehabilitation (EP) initiated before CRT improves functional capacity compared with usual care (UC). METHODS: FIT4TREAT (ClinicalTrials.gov: NCT05418842) was a prospective, single-center, randomized clinical trial. Adults with HNC proposed for definitive CRT were randomly assigned (1:1) to EP or UC. EP consisted of supervised combined aerobic and resistance exercise performed three times per week from baseline until radiotherapy initiation. The primary outcome was the six-minute walk distance (6MWD) at the end of the pre-treatment period. Secondary outcomes included muscle strength, lower-limb functionality, body composition, and HRQoL assessed using the EORTC QLQ-C30 and QLQ-HN43. RESULTS: Between May 2021 and February 2025, 47 patients were enrolled; 40 were included in the primary analysis. After adjustment for baseline 6MWD and the randomization stratification variables, EP resulted in a significantly greater pre-treatment 6MWD than UC (adjusted between-group difference, 28.6 m; 95 % CI, 4.1-53.1; P = 0.023). EP also improved lower-limb functionality (P < 0.001) and was associated with better preservation in the QLQ-C30 summary score (P = 0.008), social functioning (P = 0.038) and body image (P = 0.011). CONCLUSION: EP before definitive CRT improves functional capacity and may help preserve HRQoL in patients with HNC, supporting its potential integration into routine oncology care.

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PubMed2026

Deciphering S-nitrosylation-regulated metabolic networks in postmortem beef based on label-free modificomics: Identification of ferroptosis as a novel quality-related pathway.

This study elucidated the molecular mechanisms of S-nitrosylation on postmortem beef metabolism and quality based on the label-free modificomics. Varying degrees of S-nitrosylation were exogenously induced in beef semimembranosus (SM) muscle. Results indicated that a high S-nitrosylation level significantly increased beef pH and Warner-Bratzler shear force (WBSF) while reducing centrifugal loss (P < 0.05). A total of 828 S-nitrosylated proteins and 1458 modification sites were identified, of which 114 sites on 81 proteins (DSNPs) exhibited differential modification abundance, representing an increase of 125% compared with previous proteomics studies. DSNPs were mainly involved in glycolysis, the tricarboxylic acid cycle, oxidative phosphorylation, calcium signaling, cell structure, and ferroptosis. Notably, this study provides the first evidence in postmortem muscle that S-nitrosylation regulates key ferroptosis-related proteins, including ACSL, CP, and TF, offering new insights into the link between S-nitrosylation and the ferroptosis pathway in meat. Correlation analysis demonstrated that TF was significantly negatively correlated with pH and WBSF, but positively correlated with centrifugal loss (P < 0.05). Collectively, protein S-nitrosylation critically modulates postmortem beef quality through the coordinated regulation of multiple metabolic processes. More importantly, the identification of ferroptosis as a S-nitrosylation-sensitive pathway provides a new perspective for regulating meat quality through protein post-translational modifications.

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PubMed2026

Effects of digital health-based exercise interventions on older adults with sarcopenia: Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Sarcopenia, the progressive loss of muscle mass and function, impairs independence in older adults. Digital health exercise interventions are scalable solutions for older adults with sarcopenia. This systematic review and meta-analysis aimed to synthesize the evidence on their efficacy in populations with clinically diagnosed sarcopenia and identify influential intervention characteristics associated with treatment outcomes. METHODS: We systematically searched PubMed, EMBASE, Web of Science, Cochrane Library, CINAHL, CNKI, and Wanfang on May 20, 2026, with no date restrictions. We included randomized controlled trials involving adults aged ≥60 with sarcopenia receiving digital exercise interventions. Two reviewers independently screened studies, extracted data, and assessed risk of bias; analyses were performed using R and Review Manager. RESULTS: Fourteen trials (n = 927) were included. Digital interventions showed potential improvements in muscle mass (MD = 0.25, 95%CI:0.03-0.46, 95% PI:-0.36 to 0.85), muscle strength (MD = 2.14, 95% CI:1.18-3.11, P < 0.001), balance ability (SMD = 0.31, 95% CI:0.12-0.51, P = 0.001), walking performance (SMD = 0.55, 95% CI:0.21-0.89, 95% PI:-0.70 to 1.79), and physical function (SMD = 0.89, 95% CI:0.08-1.71, 95% PI:-2.33 to 4.12), but not quality of life (SMD = 0.08, 95% CI:-0.19 to 0.35, P = 0.53). Exploratory subgroup analyses suggested that factors such as supervision, program duration, and measurement tools may influence outcomes; however, formal tests for subgroup differences were generally non-significant, and consistent patterns across all metrics were not observed. CONCLUSION: Digital exercise interventions show potential for managing sarcopenia in older adults, though the very low to moderate certainty of evidence indicates that true effects may differ substantially from observed estimates. This review explores potential roles of intervention design, supervision, and multimodal delivery. Future research should adopt rigorous designs and longer follow-up to validate results and enhance clinical application. TRIAL REGISTRATION: PROSPERO CRD420251135174.

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PubMed2026

Exercise Snacks Are Feasible to Perform in the Real World and Improve Physical Capacity for Adults Living With Non-Insulin Treated Type 2 Diabetes: A Randomised Trial.

AIMS: To investigate the feasibility and preliminary efficacy of a 12-week remotely-delivered exercise snacks (ES) intervention in adults with type 2 diabetes. MATERIAL AND METHODS: Insufficiently active adults with type 2 diabetes (N = 69; 46 females; mean age ± SD: 58 ± 11 years) were randomised to an ES or mobility/stretching comparator group (CON), which involved 4 × 1-min bouts of either vigorous or low intensity exercise, respectively, on ≥ 5 days/week. The primary outcome was feasibility based on adherence. Secondary outcomes included exercise enjoyment (1-7 scale), rating of perceived exertion (RPE; 0-10 scale), heart rate (HR), haemoglobin A1c (HbA1c), blood biomarkers of cardiometabolic health, 30-s sit-to-stand capacity, grip strength, estimated maximal oxygen uptake, and anthropometrics. RESULTS: Weekly adherence (estimated marginal mean [95% confidence interval]: 18 bouts [16-21] for both groups; p = 0.99) and total enjoyment (ES: 4.5 [4.1-4.8] vs. CON: 4.3 [4.0-4.7]; p = 0.64) were high and not different between groups. Despite higher RPE (5.7 [5.4-6.1]) and peak HR (73 [70-77] % of age-predicted HR maximum) in ES versus CON (2.0 [1.7-2.4] and 61 [58-64] % of age-predicted HR maximum, respectively) (all p < 0.001), there were no between-group differences in the change in any secondary outcome (all p > 0.05) except for greater sit-to-stand capacity in ES after training (between-group effect estimate [95% confidence interval]: 1.9 repetitions [0.3-3.4]; p = 0.02). CONCLUSIONS: Exercise snacks were feasible to perform in the real world and improved sit-to-stand capacity to a greater extent than CON in adults living with type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT06407245.

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PubMed2026

Resistance versus concurrent training with three assigned protein targets in middle-aged and older women: a randomized 2 × 3 factorial trial.

BACKGROUND: Evidence is limited regarding whether assigned protein targets modify responses to resistance training (RT) alone or to the same RT program plus cycling (concurrent training [CT]) in middle-aged and older women. This randomized 2 × 3 factorial trial examined bioelectrical impedance analysis (BIA)-derived skeletal muscle mass (SMM; primary outcome), other body composition outcomes, muscular and functional performance, and cycle-derived estimated VO₂max. METHODS: In this randomized 2 × 3 factorial trial, 108 women aged 40-77 years were assigned to 12 weeks of supervised RT or CT (identical RT followed by cycling) and protein targets of 0.8, 1.6, or 2.2 g·kg-1·d-1. Baseline-adjusted ANCOVA tested training × protein interactions and marginal training and protein effects. Complete-case analyses included 83 participants. RESULTS: For SMM, no training-condition × protein-target interaction (p = 0.856), marginal protein-target effect (p = 0.726), or marginal training-condition effect (p = 0.273) was detected. CT had a lower baseline-adjusted week-12 BFP than RT (adjusted difference, -2.04 percentage points; 95% CI, -2.94 to -1.14; p < 0.001). RT had a higher baseline-adjusted week-12 leg-press estimated 1-RM than CT (CT - RT: -6.68 kg; 95% CI, -8.32 to -5.04; p < 0.001), whereas CT had a higher baseline-adjusted week-12 cycle-derived estimated VO₂max (adjusted difference, 4.53 mL·kg-1·min-1; 95% CI, 3.80 to 5.25; p < 0.001). No detectable marginal protein-target effects or training-condition × protein-target interactions were observed for the key secondary outcomes. CONCLUSIONS: No detectable differences in SMM or key secondary outcomes were attributable to assigned protein target. Compared with RT, CT favored estimated aerobic fitness and BFP, whereas RT favored leg-press strength. Because CT included additional cycling and greater exercise exposure, these differences cannot be attributed solely to training modality. Null protein findings do not establish equivalence among doses.

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PubMed2025

Enhanced fracture detection on radiographs with AI assistance for clinicians: a systematic review and meta-analysis.

BACKGROUND: Emergency radiographic interpretation for fractures is prone to missed or misdiagnoses. Artificial intelligence (AI) is expected to become a powerful tool to assist clinicians in fracture detection. PURPOSE: A systematic review and meta-analysis was performed to assess whether AI improves clinicians' ability to detect fractures on radiographs. MATERIALS AND METHODS: A literature search was conducted in PubMed, Web of Science, and Cochrane Library for studies published between January 1, 2010, and October 10, 2025. A meta-analysis of diagnostic accuracy studies was performed using a Summary Receiver Operating Characteristic (SROC) curve. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Subgroup analysis and meta-regression were conducted to explore potential sources of heterogeneity. RESULTS: A total of 26 studies were included . The pooled sensitivity of clinicians increased from 77% (95% CI: 72-81) to 87% (95% CI: 83-90) with AI assistance, while the pooled specificity improved from 88% (95% CI: 85-90) to 92% (95% CI: 89-94). The corresponding AUC values were 0.90 (95% CI: 0.87-0.92) before and 0.95 (95% CI: 0.93-0.97) after AI assistance. Eight studies were rated as high risk of bias. Subgroup analysis and meta-regression identified potential sources of heterogeneity, including fracture location, AI model type, high risk of bias, and reference standards. CONCLUSION: AI assistance significantly improves clinicians' diagnostic performance in detecting fractures on radiographs for extremity and trunk fractures.

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PubMed2026

Six weeks of isometric resistance training led to evidence of corticospinal but not reticulospinal adaptation in previously untrained adult males.

The latest hypothesis regarding the source of enhanced neural activation from resistance training is the reticulospinal rather than the corticospinal tract, based on invasive animal and emerging human data. The present study employed a six-week isometric resistance training intervention in a randomized controlled design to address this knowledge gap. Thirty-nine healthy, untrained males (age ~23 y, sustained contraction group n = 13, explosive contraction group n = 9, control group n = 17) underwent neuromuscular and electrophysiological testing and completed all study requirements. Maximal isometric torque (MVC) and rate of torque development (RTD) were measured during a familiarization session as well as before and after the six-week period. Transcranial magnetic stimulation was used to assess motor-evoked potential (MEP) area and silent period duration while subjects contracted to 10% of MVC. Loud sound (120 dB) was used to modulate MEP area and reaction time to visual stimuli during the StartReact test. Only the intervention groups demonstrated significant improvements in MVC (27%) and RTD (60%) (both P < 0.01), along with reduced MEP area (- 21%) and silent period duration (- 23%) (both P < 0.01). The sustained contraction group showed reduced modulation of reaction time and increased MEP suppression due to loud sound. Short-term resistance training seemed to reduce cortical inhibition and corticospinal excitability in both training groups. The study showed conflicting changes in measures purported to evaluate reticulospinal functioning. It is recommended to examine different forms of resistance training and longer training exposure in future.

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PubMed2026

Effects of acute resistance exercise on prefrontal oxygenation and task-switching performance: Considerations of loading strategies and blood flow restriction.

Although acute resistance exercise (RE) has been proposed to influence cognitive flexibility and underlying neural mechanisms, it remains unclear whether these effects vary across loading strategies and whether exercise-induced prefrontal hemodynamic responses translate into cognitive outcomes. The present study examined (1) prefrontal cortex (PFC) oxygenated hemoglobin (O2Hb) responses across exercise sets and conditions, (2) the effects of low-load (LL), LL with blood flow restriction (BFR), and high-load (HL) RE on task-switching performance, and (3) whether exercise-related PFC O2Hb responses were associated with pre- to post-exercise changes in task-switching performance. Thirty physically active adults completed three randomized, counterbalanced RE conditions consisting of four sets of barbell squats. LL was performed at 30% one-repetition maximum (1RM) with and without BFR, whereas HL was performed at 70% 1RM. Cognitive flexibility was assessed pre- and post-exercise using a modified Stroop task, indexed by switch-cost reaction time (RT) and accuracy. PFC O2Hb was assessed using functional near-infrared spectroscopy during exercise and expressed as changes from the resting baseline for each set (Sets 1-4). PFC O2Hb increased across sets, rising from Set 1 to Set 3 before plateauing, with no differences observed across conditions. Switch cost RT and accuracy did not improve from pre- to post-exercise, and no differences across conditions were detected. PFC O2Hb during the final set was not associated with changes in switch cost. These findings suggest that although acute RE elicits robust increases in prefrontal hemodynamic activity, such responses may not translate into acute improvements in cognitive flexibility.

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PubMed2026

Comparative effects of 12-week resistance training on unstable and stable surfaces on muscle stiffness, muscle co-activation, and balance in older patients with knee osteoarthritis.

OBJECTIVE: This randomized trial compared the effects of unstable resistance training (URT), involving resistance exercises on unstable surfaces, and stable resistance training (SRT), performed on stable surfaces, on muscle stiffness, co-activation, and balance in older adults with knee osteoarthritis (KOA). We hypothesized that URT would yield greater improvements by enhancing neuromuscular adaptability. METHODS: Fifty patients with KOA were randomly assigned to the URT group (n = 25) or the SRT group (n = 25). After attrition, 46 participants (URT: n = 23; SRT: n = 23) completed the intervention and were included in the final analysis. Both groups completed a 12-week supervised lower-limb resistance training program (3 sessions/week) consisting of 10 exercises performed under either unstable or stable support conditions. RESULTS: After 12 weeks of intervention, both groups showed significant reductions in pain intensity (p < 0.001). However, compared with the SRT group, the URT group demonstrated significantly greater reductions in quadriceps stiffness (p < 0.05), selected hamstring stiffness outcomes (p < 0.05), and quadriceps-hamstring co-activation (p < 0.001), alongside superior improvements in both dynamic balance and static balance (all p < 0.05). CONCLUSION: While both training modalities are effective for pain relief, URT elicited greater improvements in balance-related performance and neuromuscular-mechanical outcomes than SRT in older adults with KOA. These findings suggest that incorporating unstable support conditions into resistance training may provide additional rehabilitation benefits for this population.

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PubMed2026

Muscle mechanical and architectural adaptations in response to different endurance training modalities in older adults.

INTRODUCTION: This study examined the effects of various cycling endurance training modalities, matched for total workload, on muscle mechanical and architectural characteristics in older adults. METHODS: Fifty healthy participants (25 females, 59-79 yrs) were randomly assigned to five age and sex matched groups: one control and four workload-matched training groups (moderate-intensity continuous, heavy-intensity continuous, high-intensity interval, and heavy-intensity continuous in eccentric cycling). Training consisted of three weekly sessions over 8 weeks, with evaluations conducted at the beginning and end of the intervention with maximal voluntary isometric contractions at five different knee angles (90, 75, 60, 45, 30°) and maximal concentric and eccentric isokinetic contractions at five different knee angular velocities (45, 90, 150, 210, 250°/s). Maximum voluntary isometric torque (Tmax) and optimal knee angle (KAopt) were obtained from the isometric contractions; eccentric torque (Tecc) and maximum concentric knee angular velocity (Vmax) were obtained from the isokinetic contractions. The muscle architecture of vastus lateralis (VL) at rest (muscle thickness, pennation angle, and fascicle length) was investigated as well. RESULTS: No statistical differences were detected between groups or time points in VL architecture, in KAopt and in Vmax. A main effect of time was observed for Tmax (p < 0.001, η2p = 0.458) and Tecc (p = 0.002, η2p = 0.191) in all the investigated training groups. The within-group comparisons indicate significant increases in Tmax in the training groups, but not in the control group. CONCLUSIONS: Commonly applied endurance exercises improve muscle mechanical capacity (Tmax and Tecc) in older adults, with no structural (architectural) muscle remodelling, when matched for workload.

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PubMed2025

Efficacy of Janus kinase inhibitor combined with phototherapy in non-segmental vitiligo: systematic review and meta-analysis.

BACKGROUND: Vitiligo is a chronic autoimmune disease causing skin depigmentation and psychosocial issues. Non-segmental vitiligo often shows limited response to standard therapies. The IFN-γ-JAK-STAT pathway plays a key role, and combining JAK inhibitors with NB-UVB may improve repigmentation. AIM: To evaluate the efficacy of JAK inhibitors (baricitinib or tofacitinib) plus NB-UVB versus NB-UVB without JAK inhibitors in adult NSV. METHODS: PubMed, Cochrane, and ClinicalTrials.gov were searched till August 2024 for randomized controlled trials. Four studies, comprising 217 adults (121 in the combination group and 96 in the control group), were analyzed using RevMan 5.4. Bias was assessed via Newcastle-Ottawa, Cochrane ROB-2, and ROBINS-I tools. RESULTS: Combination therapy significantly reduced total VASI compared to controls (MD = -4.96, 95% CI [-9.29, -0.63], p = 0.02), with a greater effect on sensitivity analysis (MD = -6.84, p = 0.0007). Significant reductions were seen in face/neck (MD = -0.17, p = 0.002), trunk (MD = -3.62, p = 0.0001); acral (MD = -0.85, p = 0.0002) and extremity (MD = -4.61, p < 0.00001) regions after sensitivity analysis. Patients were more likely to achieve ≥50% (RR = 6.87, p < 0.00001) and ≥75% (RR = 15.13, p = 0.006) repigmentation. CONCLUSIONS: JAK inhibitor plus NB-UVB markedly improves the repigmentation in adult NSV compared to NB-UVB alone.

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PubMed2026

Acute Performance, Mechanical and Thermal Effects of Isometric Conditioning Versus Standardized Volleyball Pre-Training Activation in Highly Trained Male Players.

This study compared acute performance, neuromuscular, and thermal responses to a maximal isometric conditioning activity (ICA) versus a standardized volleyball pre-training activation (VPA) in highly trained male volleyball players, and to explore putative mechanisms underpinning post-activation performance enhancement (PAPE) considering training load. In a randomized crossover, 14 men (27 ± 3 y) completed two sessions: VPA (mobility/plyometric drills; 9 min), and ICA comprising 3×5×3-s maximal isometric back-squat contractions (knee angle 120°; 3-min inter-set rest). Countermovement jump (CMJ) height (primary), relative peak power (PP), RSImod, and contraction time (CT) were recorded pre and 3, 6, 9, and 12 min post. Rectus femoris muscle viscoelastic properties and skin surface temperature (SST) were assessed at matched time points. Analyses used repeated-measures ANOVA, responder analysis, correlations, and regression. Period×Sequence interactions favored ICA for CMJ and PP when delivered in Period 2 (lower training volume): ∆CMJ was higher under ICA versus VPA (p = 0.005, d = 1.20); PP likewise greater (p = 0.026, ηp2 = 0.35). ICA yielded more beneficial responders than VPA (9/14 vs 1/14; McNemar exact p = 0.021). In Period 2, reductions in rectus femoris muscle stiffness independently predicted CMJ gains (β_std = -0.495, p = 0.005), whereas SST changes did not (p = 0.974). RSImod and CT showed no differences. A brief, high-effort isometric squat protocol was associated with superior acute improvements in jump performance compared with a standard volleyball warm-up, but this advantage emerged specifically when the preceding training volume was reduced (Period 2), suggesting that residual fatigue from training may reduce the effects of PAPE. Gains align with neuro-mechanical rather than thermal mechanisms, supporting ICA as a practical, equipment-minimal priming strategy for elite volleyball.

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PubMed2026

Effects of a situational interest-based rotational fitness training program on positive affect in university students: A randomized controlled trial.

BACKGROUND: To evaluate whether a 12-week situational interest-based rotational fitness program improved positive emotional states in university students, to compare module-specific effects, and to examine whether the intervention moderated the heart rate-emotion association. METHODS: In this 2-arm randomized controlled trial, 560 freshmen from 10 Chinese universities were assigned to an experimental (n = 280) or control group (n = 280). The experimental group completed weekly 90-minute sessions covering strength, endurance, speed, and agility modules; controls received regular physical education. Positive emotional states were assessed using the positive well-being subscale of the Subjective Exercise Experiences Scale through ecological momentary assessment at 3 points per session, yielding over 14,000 observations. Linear mixed-effects models tested group, time, group × time, heart rate, and heart rate × group effects. Assessors and analysts were blinded. Ethical approval for the trial was granted by the Institutional Review Board of Capital University of Physical Education and Sports (2025A055). RESULTS: Improvement was greater in the experimental group than in controls (EMM change: 1.843 vs 0.505; difference = 1.338, 95% confidence interval [CI]: 1.275-1.400, P < .001). At week 12, the raw between-group difference was 1.85 (d = 2.23), and all group × week interactions from weeks 2 to 12 were significant. Heart rate positively predicted emotional states in controls (B = 0.005, 95% CI: 0.003-0.007), but this association was attenuated in the experimental group (interaction B = -0.008, 95% CI: -0.011 to -0.005). Strength and agility showed significant improvements, while endurance produced consistently higher emotional states across assessment points. Heart rate moderation was significant for strength and endurance, but not speed or agility. CONCLUSION: The rotational program improved positive emotional states more than regular physical education, although effects varied by module. Strength showed the most robust benefit. The program also weakened, but did not eliminate, the heart rate-emotion association during more demanding activities.

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PubMed2026

The impact of acute sleep fragmentation on muscle blood flow responses to handgrip exercise.

Sleep fragmentation is reported to impair resting vascular function. The aim of this study was to test the hypothesis that acute sleep fragmentation would impair muscle blood flow during exercise. Twenty adults (10 females and 10 males) participated in a randomized crossover study that included one night of habitual sleep and one night of fragmented sleep. Sleep was assessed at home using wrist actigraphy. Arousals from sleep were increased by an audio alarm sounding every 30 min. The morning following each sleep condition, participants performed single handgrip contractions and rhythmic handgrip exercise at 15%, 30%, and 45% MVC. Forearm blood flow (FBF) was measured using Doppler ultrasound. Nightly awakenings and wake after sleep onset significantly increased by 18% and 43%, respectively, after fragmented sleep, leading to lower sleep duration (P < 0.001). Peak FBF and total hyperemic responses following single contractions were similar between sleep conditions (all P > 0.05). During rhythmic handgrip exercise, brachial artery dilation was reduced after fragmented sleep (main effect: 5.5 ± 4.8 vs. 3.3 ± 3.7%; P = 0.01), leading to a lower FBF response to rhythmic exercise (main effect: 122 ± 58 vs. 110 ± 56 mL/min; P = 0.04). Endothelial sensitivity to shear rate was similar between sleep conditions (habitual vs. fragmented: 0.039 ± 0.024 vs. 0.042 ± 0.031%/s-1; P = 0.77). In summary, acute sleep fragmentation decreases skeletal muscle blood flow during exercise. This finding suggests that blunted oxygen delivery may be a contributing factor for exercise performance deficits after disturbed sleep.NEW & NOTEWORTHY We demonstrate that one night of fragmented sleep decreases steady-state blood flow and vascular conductance during low- to moderate-intensity handgrip exercise. This impairment was not due to an impaired rapid vasodilation to single contractions nor altered endothelial sensitivity to shear rate as these variables were unchanged after acute sleep fragmentation. These results reveal a negative impact of disrupted sleep on the steady-state muscle vasodilatory response to rhythmic contractions.

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PubMed2026

Effects of an actuated ankle exoskeleton on walking stability in healthy adults: a controlled laboratory study.

BACKGROUND: Ankle exoskeletons are widely used to reduce the metabolic cost of walking, yet their effects on walking stability during unperturbed gait remain insufficiently understood. Walking stability can be characterized using complementary measures that capture stride-to-stride variability, global temporal organization, and local dynamic stability. Understanding how walking with an actuated ankle exoskeleton system influences these different aspects of gait stability is essential for the safe design and control of wearable robotic devices. METHODS: Eighteen healthy adults walked on a treadmill at a constant speed (1.1 m/s) with and without an actuated bilateral ankle exoskeleton in a randomized crossover design. Spatiotemporal variability was quantified using coefficients of variation (CoV) of stride length, step width, and stance ratio. Global gait stability was assessed using detrended fluctuation analysis of stride time. Local dynamic stability was evaluated using maximum Lyapunov exponent calculated for the trunk, hip, upper leg, lower leg, and foot. Paired-samples two-sided t-tests were used to compare conditions. RESULTS: Walking with the ankle exoskeleton resulted in increased stride-to-stride spatiotemporal variability, reflected by higher CoV values for stride length (p < 0.001) and stance ratio (p = 0.005), while mean stride length and step width remained unchanged. Mean stance ratio was reduced in the exoskeleton condition (p < 0.001). Global gait stability did not differ between conditions, indicating preserved long-range temporal gait organization. Local dynamic stability increased at the lower leg (p < 0.001) and foot (p = 0.019) when walking with the exoskeleton. CONCLUSIONS: Walking with the actuated ankle exoskeleton alters gait control across multiple levels during steady walking. While stride-to-stride variability in stride length and stance ratio increased, global gait stability remained unchanged. Local dynamic stability was increased at the lower leg and foot, suggesting segment-specific effects of ankle-level assistance close to the assisted joint. However, these findings should be interpreted as the combined effect of wearing the exoskeleton and receiving active assistance, rather than the isolated effect of plantarflexion assistance. These results provide insight for the design and control of ankle exoskeletons with respect to stability-related effects during walking.

Humans↗

PubMed2026

Quantitative assessment of the fingerprint evidential value using machine learning.

Fingerprints as physical evidence have long supported criminal investigation and adjudication. In practice, however, fingerprint identification relies mainly on examiners' experience. Furthermore, expert opinions tend to be categorical, even though the opinions with the same conclusion could differ substantially in evidential strength. To quantitatively assess fingerprint evidential value, this study proposes a machine learning-based framework as an interpretable decision-support tool. A lightweight residual one-dimensional convolutional neural network was constructed, incorporating channel recalibration and a similarity-driven attention mechanism to learn adaptive contribution weights for different matched minutiae (minutiae for short). Controlled experiments revealed that the predicted evidential value increased with the number of minutiae and was significantly influenced by the quality of minutiae. With 10 minutiae, the mean predicted scores were 4.49, 7.00, and 9.09 for blurred, moderately blurred, and clear minutiae, respectively. Multiple regression analysis indicated that replacing a pair of blurred minutiae with a pair of clear minutiae increased the score by 0.492, whereas replacing it with a pair of moderately blurred minutiae increased the score by only 0.216. By mapping predicted scores to graded levels of evidential strength, the framework contributes to a paradigm shift from categorical expert opinions to graded ones, helping courts evaluate fingerprint evidence more scientifically.

Humans↗