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Arthroscopic lateral ankle ligament reconstruction with hamstring graft (ALALR) generally yields good clinical outcomes and enables an early return to sports. However, no studies have specifically evaluated persistent functional deficits, particularly regarding jumping ability, following ALALR with hamstring autograft. To evaluate post-operative ankle stability via jumping ability in patients six months after ALALR with hamstring autograft compared to healthy patients. Retrospective comparative study; METHODS: Forty-nine patients who underwent ALALR with hamstring graft and forty-nine healthy controls performed bipodal drop jump (DJ), single hop (SNH), side hop (SDH), and single-leg vertical jump (SVJ) tests. Measurements included jump height (m), jump distance (m), lateral jump time (s), and reactive strength index for bipodal drop jump (DJ-RSI). These metrics were compared between groups. Additionally, single hop, side hop, and SVJ results were compared between healthy participants and both the injured and contralateral legs of ALALR patients. At an average of 5.8 ± 0.9 months postoperatively, ALALR patients showed no significant differences in DJ-RSI, Single hop, Side Hop tests or SVJ compared to the control group (p > 0.05). Vertical, lateral, and anteroposterior jumping performances were similar for both the injured and contralateral legs (p > 0.05). No statistically significant difference in jumping ability was detected between patients six months after ALALR with hamstring autograft and healthy controls. As a non-significant result does not establish equivalence, these findings should be interpreted as descriptive and suggest that jumping ability is not markedly impaired, which may support return to sport after the ALALR procedure. III.
Uphill running is widely used in athletic training to improve lower-limb strength, jumping performance, running ability, and aerobic capacity. However, randomized controlled trials (RCTs) have reported inconsistent findings, and no prior review has focused exclusively on uphill running across these domains. This systematic review and meta-analysis aimed to evaluate the effects of structured uphill running on muscle strength, jumping performance, running time, and aerobic capacity in athletes and recreationally active adults. Six databases (CINAHL, Embase, PubMed, Scopus, SPORTDiscus, Web of Science) were searched up to June 2025 for RCTs comparing uphill running with downhill, level ground, or usual training. Methodological quality was assessed using the Physiotherapy Evidence Database scale and Cochrane risk-of-bias tool. A random-effects meta-analysis was performed, with effect sizes expressed as standardized mean differences (SMDs) and 95% confidence intervals (CIs). Thirteen RCTs (2006-2023; n = 308; mean Physiotherapy Evidence Database score = 5.4) were included, with 7 contributing to quantitative synthesis. Only trials reporting isokinetic muscle strength, jumping performance, and aerobic capacity outcomes provided sufficient data for meta-analysis. Protocols commonly involved 10 to 14 uphill sprints of 30 seconds at a ~10% gradient, performed 2 to 3 times weekly over 2 to 8 weeks. Narrative synthesis showed improvements in running economy, repeated sprint ability, and aerobic outcomes such as ventilatory threshold and lactate clearance. However, meta-analysis revealed no significant effects on isokinetic knee strength (SMD = 0.09, 95% CI = -0.41 to 0.59, P = .73; I2 = 0%), jumping performance (SMD = 0.15, 95% CI = -0.39 to 0.70, P = .59; I2 = 0%), or aerobic capacity (SMD = 0.31, 95% CI = -0.11 to 0.74, P = .15; I2 = 0%). Although statistical heterogeneity was low, the overall certainty of the evidence remained low because of the limited number of trials contributing to each meta-analysis, small sample sizes, and variability in intervention protocols and comparator conditions. Uphill running may induce favorable neuromuscular and aerobic adaptations, but meta-analysis findings did not confirm significant pooled effects on knee strength, jump performance, or aerobic outcomes. Future high-quality RCTs with standardized gradients, sufficient sample sizes, and longer durations are needed.
Dynamic bipedal jumping is highly sensitive to takeoff momentum and landing configuration, making the direct execution of purely offline-optimized trajectories unreliable on full-sized humanoid robots in the presence of modeling inaccuracies and execution uncertainties. A key challenge is the gap between dynamic feasibility predicted offline using simplified models and executability on physical hardware, because such models cannot fully capture full-body dynamics, actuator behavior, contact transitions, and execution uncertainty. This paper proposes an offline-to-online planning and whole-body control framework for robust in-place jumping of full-sized humanoid robots. The framework integrates phase-consistent offline trajectory optimization, lightweight online reference reshaping, constraint-aware whole-body control, and actuator-level command mapping to improve execution robustness without online re-optimization. In the offline stage, centroidal-dynamics-based trajectory optimization generates jumping references subject to kinematic-consistency and contact-feasibility constraints. During execution, these references are adapted online using real-time state estimates to compensate for takeoff deviations and regulate the landing state; a weighted quadratic-programming whole-body controller then tracks the adapted references. Hardware experiments on a 79.5 kg humanoid robot demonstrate repeatable in-place vertical jumps with a height of approximately 30 cm and stable landings. The results show that robust jumping on a full-sized humanoid robot can be achieved by combining offline nominal trajectory generation with online execution adaptation rather than relying on exact reproduction of the offline trajectories.
Athletes are advised to take an individualized approach when adjusting training and recovery to their menstrual cycle (MC), due to potential variation in the effect of the MC on training, recovery, and performance. To investigate the effect of MC phase, defined based on literature and symptom occurrence/severity, on recovery measures and performance in an elite female ski jumper. A world-class female ski jumper collected data on her MC, MC-related symptoms, recovery measures (resting heart rate and heart rate variability), and performance. The MC was divided into menstrual bleeding (MB), days 1 to 5; premenstruation (PM), 1 to 4 days before the start of the next MC; and mid-phase (MP), the remaining days. Ski jumping results were recalculated to adjust for wind points and take-off speed to get a physical performance score (Spp). Data are reported as median (interquartile range). MC length was 24 days (20-26), and symptom severity of depressive and physical symptoms was highest during the last 2 days of the cycle. Resting heart rate was 45 (43-47) beats/min in MB, 47 (45-48) beats/min in MP, and 48 (45-49) beats/min in PM. Heart rate variability was 78 (67-82) ms in MB, 70 (65-76) ms in MP, and 74 (67-85) ms in PM. Performance data in normal hill and large hill followed somewhat opposite patterns, with a potentially better performance in normal hill and worse in large hill during PM. Recovery measures and performance in individual athletes can be influenced by MC phase, with these seemingly being most influenced by cycle-related symptoms.
Homologous replacement of genomic sequences with large DNA fragments (> 100 bp) holds great potential for crop breeding, yet an efficient method to achieve such edits is lacking in plants. Here, in rice, we developed template-jumping prime editing (TJ-PE), a recently reported PE strategy for large targeted insertion, as an efficient tool for homologous replacement with DNA fragments ranging from dozens to hundreds of base pairs, and using TJ-PE, we replaced genomic fragments of up to 340 bp with homologous fragments of the same length. In addition, our TJ-PE tool also enabled precise deletion of 944- to 2024-bp fragments in rice, with efficiencies of up to 34.6% for c. 2000-bp precise deletions. Collectively, this study expands the editing scope of PE in rice and establishes TJ-PE as a generalist tool for precise deletion and replacement of large DNA fragments.
Inter-limb asymmetry is frequently evaluated during bilateral tasks such as the countermovement jump (CMJ), typically using discrete peak-based metrics. However, these approaches may inadequately capture the complex, time-varying nature of inter-limb coordination. This study examined inter-limb asymmetry during CMJ in youth football players using both discrete and continuous assessments, with consideration of limb dominance. Forty-three male youth academy football players (14 ± 1.1 years) performed three maximal bilateral CMJs with data collected using dual force platforms and three-dimensional motion capture. Inter-limb asymmetry was quantified using discrete symmetry indices for peak vertical ground reaction force (GRFvert), joint displacements, and joint moments, alongside time-series approaches including statistical parametric mapping (SPM1D) and the normalized symmetry index (SInorm). Asymmetry threshold breaches (±10% and ±20%) and their duration across the movement cycle were assessed, with comparisons between dominant and non-dominant limbs. Discrete metrics indicated low levels of inter-limb asymmetry at the group level, with mean values typically within ±10% thresholds. In contrast, time-series analyses revealed frequent, phase-specific asymmetry within individual trials, particularly for joint moments, despite no significant group-level differences identified using SPM1D. A ±10% GRFvert asymmetry breach occurred in every trial. Limb dominance had minimal influence, except for longer GRFvert breach durations on the non-dominant limb. Inter-limb asymmetry during bilateral CMJ is observed frequently when assessed using time-series methods, despite apparently symmetrical discrete outcomes. These findings demonstrate that reliance on peak-based symmetry metrics may overlook substantial phase-specific asymmetry, with implications for the interpretation of bilateral loading during athlete monitoring and rehabilitation contexts.
(1) the acute effects of RWU on physical performance, body temperature (BT), and rating of perceived exertion (RPE) in basketball players; and (2) individual-level performance improvements across different RWU methods. Three databases were searched for RWU studies in basketball players. An individual participant data meta-analysis was conducted using a two-stage approach with multilevel models, including adjustments for small sample sizes. Effect sizes were expressed as standardized mean changes (SMC) for within-group comparisons and standardized mean differences (SMD) for between-group comparisons. Seven studies (n = 82; 35 females, 47 males) were included, with individual raw data obtained from three. Compared with the control condition, the RWU resulted in better preservation of jumping (SMD = 0.64) and change-of-direction (COD) performance (SMD = -0.83), while showing no significant differences in isometric mid-thigh pull (IMTP) peak force (SMD = 0.34), BT (SMD = 0.72), or RPE (SMD = 0.61). These effects were largely driven by greater declines in the control than in the RWU for jumping (SMC = -1.24 vs. -0.53), COD (SMC = 1.00 vs. 0.44), and IMTP peak force (SMC = -0.68 vs. -0.28). Across five interventions from three studies with individual data, the plyometric protocol showed the highest proportion of improvements (CMJ: 100%; COD: 93.3%) compared with the control condition. Preliminary evidence suggests that RWU may be an effective strategy to maintain physical performance and BT in basketball players. However, given the limited number of studies and the high degree of individual variability, further research is required.
Neuromuscular performance is influenced by diurnal variation, but it remains unclear whether sex moderates these patterns in team sport athletes. This study examined whether sex moderates the effect of time of day on neuromuscular performance in volleyball players. One hundred and two volleyball players (46 males and 56 females) completed a randomized battery of tests in the morning (08:00-10:00) and evening (18:00-20:00) on separate days. The battery included vertical jumps (squat, countermovement, and spike jumps), spike performance (standing and jumping spike), agility (modified T test), isometric handgrip strength, and dynamic balance (modified star excursion balance test). A significant sex-by-time interaction was observed in squat jump (P  =  .002, ηp2=.09), with males showing higher evening values, whereas females showed no significant change. A sex-by-time interaction was also found in jumping spike (P = .045, ηp2=.04), agility (P = .027, ηp2=.05), and dynamic balance (ie, posterolateral) on the dominant leg (P = .005, d = 0.26), reflecting different response patterns between sexes. No significant changes were observed in other dynamic balance directions (P > .05). A significant time-of-day effect was observed, indicating higher evening performance in all jump tests (P = .005, ηp2=.08-.19), ball velocity in spike velocity (P = .002, ηp2=.09), and isometric handgrip strength (P = .001, ηp2≈.10). Sex-specific differences were limited to a few tasks and were generally small in magnitude, whereas a consistent enhancement in neuromuscular performance in the evening compared with the morning emerged as the primary finding, regardless of sex.
Many fishes can propel themselves out of water, but few species exhibit the intentional, repeated jumping behavior as seen in freshwater hatchetfishes (Ostariophysi: Characiformes: Gasteropelecidae). Freshwater hatchetfishes have a unique body plan characterized by a deep keel and enlarged pectoral fins, which are specialized for ballistic jumping behavior to avoid predation. Rapid underwater and aerial escape behaviors are likely mediated by multiple sensory modalities, including visual and mechanosensory systems. We used fluorescent staining to visualize the neuromasts of the lateral line system and high-speed videography to quantify aerial escape responses induced by a custom vibrational apparatus in two species, Gasteropelecus maculatus and Thoracocharax stellatus. Behavioral experiments were conducted using fish pairs (one species per pair) across a 2×2 factorial design: light vs. dark (infrared) and intact vs. chemically ablated (neomycin-treated) lateral line systems. Behavioral outcomes were categorized as no response, underwater C-start, or aerial escape, followed by kinematic analyses of the jumps. Morphological analysis revealed an unusual lateral line system characterized by modified cranial and trunk canals alongside a massive proliferation of superficial neuromasts, particularly on the dorsal surface of the head and on the ventral keel. Behavioral results demonstrated that fish with ablated lateral line systems performed significantly fewer escape maneuvers than intact individuals, regardless of light condition. Furthermore, lateral line-ablated fish exhibited significantly shorter jump path lengths, reduced jump durations, and lower maximum vertical displacements. While fish jumped at remarkable speeds (mean: 56 ± 14 BL/s), maximum jump velocity and most body orientations (pitch and yaw) did not vary significantly across experimental conditions. Our findings demonstrate that the mechanosensory lateral line system is an important sensory modality contributing to escape performance in hatchetfishes, particularly in response to vibrational stimuli, while the relative roles of vision and hearing warrant further study. We conclude that both the highly derived body shape and the lateral line system of freshwater hatchetfishes are evolutionarily tuned to enhance survival through rapid detection of mechanosensory stimuli and execution of aerial escapes.
The purpose is to evaluate how blood flow restriction (BFR) and resistance training (RT), influence muscle adaptation and sports performance in team-athletes. Preferred Reporting Program for Systematic Reviews and Meta-analyses (PRISMA) guidelines are adhered to in the conduct of this study. From the beginning to September 11, 2025, a thorough literature search was conducted in PubMed, Web of Science, Cochrane Library, and SPORTDiscus. Subsequently, a random-effects meta-analysis was performed to synthesize data on muscle adaptation and sports performance. The meta-analysis included 12 studies involving 859 team-athletes. Results indicated that, compared to RT alone, the addition of BFR significantly induced muscle hypertrophy (SMD = 0.32, 95% CI: 0.05 to 0.58, P = 0.02, I² = 4%) and improved muscle strength (SMD = 0.42, 95% CI: 0.18 to 0.66, P<0.001, I² = 10%). Jumping or sprint performance did not show any statistically significant differences. BFRT slightly improves the muscle hypertrophy and strength of team-athletes, but has no significant increase in explosive power output such as jumping and sprinting. It can be used as a complementary means of load management, but should be interpreted with caution. The optimal prescription for transforming it into explosive power should be explored in the future.
Plyometric training (PT) is a popular method of improving explosive power, speed, and agility in adolescent athletes. Nevertheless, earlier reviews have been mainly based on individual performance domains, individual sports or general youth groups. It is therefore not clear whether the effects of PT differ based on sex, type of sport, frequency of training or duration of intervention. This meta-analysis and systematic review investigated the impact of PT on jumping, sprinting, and agility performance in adolescents. PubMed, Web of Science, and Embase were searched from database inception to 1 January 2025, with an updated search on 30 January 2026. Randomized controlled trials that included healthy adolescents aged 10-19 years were included. Conventional random-effects models were used to pool the effects of PT on jumping, sprinting, and agility performance as standardized mean differences (SMDs) with 95% confidence intervals (CIs). To account for multiple effect sizes contributed by the same study, dependency-adjusted analyses were additionally conducted using three-level random-effects models with CR2 cluster-robust variance estimation. A total of 63 studies were included. Conventional random-effects analyses showed that PT significantly improved jump performance (SMD = 0.648, 95% CI [0.523-0.772]; P < 0.001), sprint performance (SMD = -0.496, 95% CI [-0.609 to -0.383]; P < 0.001), and agility performance (SMD = -0.659, 95% CI [-0.851 to -0.467]; P < 0.001). Dependency-adjusted analyses confirmed the robustness of these findings for jump performance (SMD = 0.613, 95% CI [0.447-0.779]; P < 0.001), sprint performance (SMD = -0.414, 95% CI [-0.583 to -0.245]; P < 0.001), and agility performance (SMD = -0.595, 95% CI [-0.796 to -0.394]; P < 0.001). Benefits were more consistent with longer intervention durations, whereas sex- and sport-specific subgroup findings remained exploratory because of small subgroup sizes and heterogeneity. PT seems to be effective in enhancing jumping, sprinting, and agility performance among adolescents, especially when the interventions are continued at least 10 weeks. However, between-study heterogeneity, testing protocol variability, and small sample sizes in some sex- and sport-specific studies limit the generalizability of subgroup results. Future randomized controlled trials should use standardized outcome measures, report training dose and adherence in detail, and have a higher proportion of female participants. PROSPERO registration: CRD42024627316.
Show jumping performance depends on the rider's ability to regulate the horse-rider system while maintaining postural stability under dynamic constraints. Although rider biomechanics has been investigated in various equestrian contexts, integrated analyses combining 3D kinematics with rein and stirrup kinetics during jump-approach remain limited. This study aimed to analyse how approaching an obstacle changes a rider's control strategies by comparing sitting canter, two-point canter in straight line without obstacle and jump-approach canter (defined here as the five strides before obstacle) in 16 intermediate show jumpers performing over a vertical obstacle (110 cm) on both left and right canter leads. Full body kinematics and bilateral rein tensions and stirrup forces were recorded simultaneously. Compared with sitting canter, jump-approach canter was associated with significantly reduced head and lumbar sagittal range of motion, with riders adopting a more erect trunk position, supporting the hypothesis that riders enhance postural stabilization when preparing for obstacles. Stirrup forces were highest in two-point seat canter and exhibited significant lead-dependent asymmetry, with greater outside stirrup loading during straight-line conditions that diminished during approach. Rein tension increased during approach but remained bilaterally symmetrical across all conditions. These findings reveal a functional dissociation between upper-limb communication (symmetrical rein control) and lower-limb stabilization (asymmetrical stirrup loading), suggesting that riders decouple balance regulation from guiding aids to optimize horse-rider coordination during show jumping approach phases.
Mental health among young people and suicidality are major ongoing public health issues. This study aims to provide updated epidemiological information on youth suicides in Austria. Suicide and population data for 10-19-year-olds were obtained from Statistics Austria. We examined the distribution of suicide methods, age, sex and regional differences, as well as monthly distribution of suicides for the period 2015-2024. In addition, we calculated trends in youth suicides using annual suicide rates for boys and girls between 2005 and 2024 and assessed if the pandemic year (2020) resulted in changes in suicide rates. A total of 302 youth suicides (29.5% girls) were registered between 2015 and 2024, corresponding to an overall suicide rate of 3.4 per 100,000 individuals (boys 4.7/100,000, girls 2.1/100,000; male-female ratio 2.2:1). Total suicide rate of 10-14-year-olds was 0.6/100,000 children, and total suicide rate of 15-19-year-olds was 6.1/100,000 adolescents. Hanging was the most frequent method in both sexes, followed by jumping or lying before a moving object and jumping from a high place. Significant regional differences regarding suicide rate were found. Furthermore, downward time trends were observed between 2005 and 2024 for overall suicide rates and suicide rates among boys but there was a trend towards an increase at the onset of the pandemic in 2020. Youth suicide rates in Austria continued to decline in the time period 2005-2024, but COVID-19 marked a trend towards an increase in suicide rates. The present findings are relevant to provide information on ongoing discussions on youth suicide.
The aim of this study was to analyze the impact of an Anterior Cruciate Ligament (ACL) injury on movement variability (MV) and biomechanical variables in female basketball players during a drop vertical jump (DVJ) task, both with and without a ball. Female basketball players (n = 15) participated in this study. The participants performed two jump in each of six conditions (total = 12 jumps) in randomizer order: (i) Bilateral No Ball (2NB)-two-leg jump without a ball; (ii) Bilateral Ball (2B)-two-leg jump with a ball; (iii) ACL No Ball (ACLNB)-injured-leg jump without a ball; (iv) ACL Ball (ACLB)-injured-leg jump with a ball; (v) No ACL No Ball (NOACLNB) -uninjured-leg jump without a ball; (vi) No ACL Ball (NOACLB)-uninjured-leg jump with a ball. DVJ performance parameters were assessed using an accelerometer placed on the lower back and a force platform. MV was quantified using the multiscale entropy (MSE) derived from the acceleration data. The Complexity Index (CI) was also calculated. The ACLB condition exhibited the highest sample entropy (SampEn) value across all scales, followed by the 2B and NOACLB conditions, whereas ACLNB showed the lowest values. The CI also indicated significant variability across conditions. For linear biomechanical variables, significant differences were only observed in contact time (CT) between NOACLB and NOACLNB. The inclusion of a task constraint did not result in differences between ACL and NOACL groups in linear jumping performance metrics. However, nonlinear MV analyses, using MSE and CI, revealed condition differences.
Anterior knee pain (AKP) is highly prevalent in jumping sports and represents a frequent cause of functional limitation among basketball players, with patellar tendinopathy considered the most common underlying cause. While AKP has been extensively studied in elite and collegiate athletes, limited evidence is available for semi-professional players, who represent the majority of competitive basketball participants and often face high training demands with limited medical support. This study aimed to investigate the epidemiology of AKP and identify associated risk factors in semi-professional male basketball players. A cross-sectional, web-based survey was conducted among players competing in Serie B-D in two regions of Italy. AKP was defined using a combined screening question and anatomical pain localization. Prespecified demographic, anthropometric, training-related, competitive, occupational, and lifestyle predictors were collected via a self-administered questionnaire. Knee-related functional impairment was assessed using the Oslo Sports Trauma Research Centre Overuse Injury Questionnaire (OSTRC-O2-IT). Associations between predictors and AKP were examined using Bayesian multivariable logistic regression. Model-based predicted probabilities were also estimated across weekly training load. A total of 371 valid responses were included in the final analysis from 549 survey responses, corresponding to approximately 36.6% of the estimated target population. The prevalence of self-reported AKP was 23.5% (95% CrI 19.4-28.0). Players with AKP reported substantially greater functional impairment than AKP-negative players (mean OSTRC Severity Index Score 32.9 ± 20.9 vs. 3.7 ± 13.0). Higher weekly training volume was associated with increased odds of AKP (OR 1.18 per 60-minute increase in weekly training volume; 95% CrI 1.04-1.35), while a greater playing experience was associated with lower odds of AKP (OR 0.89; 95% CrI 0.80-0.98). Smoking was associated with higher odds of AKP (OR 2.38; 95% CrI 1.20-4.77). Model-based predicted probabilities demonstrated a progressive increase in AKP risk with higher weekly training load. AKP affected nearly one in four semi-professional male basketball players and was associated with significant functional impairment. Higher training load and smoking were associated with increased probability of AKP, whereas greater playing experience showed an inverse association. These findings highlight the importance of early screening and load monitoring to identify players at risk and support preventive strategies aimed at reducing progression toward chronic patellar tendinopathy in semi-professional basketball.
The skeletal pattern of a Class II malocclusion can increase the probability of problems with oronasal function. This study aimed to analyze the relationship between the clinical effects of dentofacial orthopedics and oral function in deficient mandibles with proclined maxillary incisors during puberty. Of 120 randomized participants, 63 with complete records were included in the final analysis (median age: 12 years; 38% females). Subjects were treated with the Sander bite jumping appliance (BJA; n = 34) or the twin block appliance (TB; n = 29) with a maxillary expansion jackscrew. The growth effect was monitored by comparisons with the findings in 63 historical untreated Class II cases. Palatal scans and cephalograms were analyzed before and at one-year intervals after treatment. Both the children and their parents reported oral symptoms and functional limitations (FLs). Palatal volume increased in both appliance groups (BJA: 860.3 mm3 [95% confidence interval (CI): 481.6-1,150.1] and TB: 958.9 mm3 [95% CI: 555.1-1,446.3]) in comparison with the untreated group (287.0 mm3 [95% CI: 193.4-426.5]; P < 0.001). However, the treatment did not affect airways. In comparison with the untreated group, the treated groups showed greater mandibular length and reduced overjet (P ≤ 0.002). No linear correlations were found between changes in dentofacial, palatal, or airway characteristics and changes in oral function. However, the palatal volume of the treated children who experienced improvement in FLs increased more than that of those who showed no FL improvement (1,220.6 mm3 [95% CI: 772.6-1,616.4] and 760.5 mm3 [95% CI: 491.6-1,002.1]; P = 0.035). Both appliances promoted mandibular growth and increased oral space, but did not significantly influence the measured upper airway widths.
High-impact physical activity delivers musculoskeletal and systemic health benefits yet remains controversial for people with hip or knee arthroplasties. This study investigates the three-dimensional kinematics and kinetics of high-impact tasks in high-functioning adults with total hip arthroplasty (THA, n = 11), total knee arthroplasty (TKA, n = 4), or unicompartmental knee arthroplasty (UKA, n = 3), compared with healthy controls (n = 57) from prior studies. They completed running, 45° change of direction (COD), countermovement jumps (CMJs), and unilateral/bilateral hopping. An 8-segment biomechanical model was used to quantify 3D joint angles and internal moments. These were time-normalised and modelled using Generalized Additive Models with covariates for group, age, and task intensity. Post-hoc contrast with controls was undertaken and reported. THA participants ran with lower hip abduction angle (peak Δ6.22°), lower external rotation angle (peak Δ7.38°), and greater hip extensor moment (peak Δ1.19 Nm/kg). During jumping and hopping tasks, THA participants also showed greater hip extensor moments (peak Δ0.41-0.67 Nm/kg), compared to controls. People with TKA and UKA consistently exhibited reduced knee extensor moments across high-impact tasks. Altered transverse-plane knee mechanics were observed in TKA and UKA, characterised by lower knee external rotation angle (peak Δ8.58°-12.54°), together with reduced internal rotation moments (peak Δ0.3 Nm/kg). High-functioning individuals with hip and knee arthroplasties can perform high-impact activities, but with altered movement strategies. The long-term implications of these biomechanical adaptations for implant loading and durability remain unclear and warrant further investigation.
Haischer, MH, Ahn, N, and Kipp, K. Lower-extremity joint function during a drop jump: relationships to performance and maximal strength. J Strength Cond Res XX(X): 000-000, 2026-Humans modulate joint stiffness during movement based on stretch-shortening cycle (SSC) loading demands. In performance tasks such as jumping, the SSC helps maximize vertical impulse through potentiation of concentric force after eccentric loading. However, joints can serve different locomotor functions (i.e., strut, spring, motor, or damper) while coordinating to achieve an overarching goal. Furthermore, while strength may benefit the ability to regulate joint stiffness under load, what joint functions facilitate optimal SSC task performance and their relationship to maximal strength is not well-understood. The purpose of this study was to describe lower-extremity joint function during a drop jump and characterize the associations to performance outcomes (jump height, ground contact time [GCT], and reactive strength index [RSI]) and relationships to maximal strength. Forty-five collegiate or club level athletes performed drop jumps off a 12-inch box while motion capture and ground reaction force data were recorded. Stance phase kinematics and kinetics were used to calculate joint functional indices (JFI) for the ankle, knee, and hip, reported as relative percentages of strut-, spring-, damper-, and motor-like mechanical behavior. Peak force from an isometric midthigh pull was also recorded as a proxy for strength, and correlations and elastic net regression analyses were performed (p ≤ 0.05). Strut, spring, motor, and damper was the rank order of JFI at all joints. Stronger athletes exhibited greater knee motor function, which was associated with a shorter GCT, greater jump height, and better RSI. Greater relative strength positively influences jump performance by enhancing the ability to generate mechanical energy.
Rugby is a collision-based team sport requiring repeated high-intensity sprinting, technical execution, and physical contact under fatigue. Although caffeine is used as an ergogenic supplement, evidence from mixed team-sport populations may not be applicable to rugby. This systematic review evaluated the effects of acute caffeine supplementation on physical and sport-specific performance, perceptual responses, and physiological markers in rugby players. PubMed, Web of Science, Cochrane Library, Scopus, and Embase were searched from inception to May 1, 2026. Randomized placebo-controlled studies examining acute caffeine supplementation in rugby players were included in the quantitative synthesis, whereas observational studies related to sleep and recovery were narratively summarized. Standardized mean differences were calculated as Hedges' g with 95% confidence intervals. Three-level random-effects models accounted for dependent effect sizes. Methodological quality and risk of bias in randomized trials were assessed using the PEDro scale and RoB 2, respectively. Observational studies were assessed using the JBI checklist, and certainty of evidence was evaluated using GRADE. Fifteen studies were included, and 13 randomized placebo-controlled trials contributed data to the meta-analysis. Acute caffeine supplementation was associated with small improvements in sprint performance (k = 11, Hedges' g = -0.41, 95% CI: -0.73 to -0.08, p = 0.02) and lower rating of perceived exertion (RPE) measured during or immediately after rugby-specific or resistance-exercise protocols (k = 9, Hedges' g = -0.40, 95% CI: -0.73 to -0.06, p = 0.02). A large positive effect was observed for passing accuracy (k = 9, Hedges' g = 1.65, 95% CI: 0.69 to 2.61, p = 0.004), but this finding showed high heterogeneity and potential small-study effects. No significant effects were found for jumping performance, strength performance, metabolic markers, or hormonal markers. Subgroup analyses did not identify moderating effects of rugby code, dose, form of administration, or competitive level. Observational evidence suggested possible sleep and recovery concerns following caffeine exposure. In rugby players, acute caffeine may improve sprint performance and passing accuracy while reducing RPE measured during or immediately after rugby-specific or resistance-exercise protocols. However, certainty of evidence ranged from low to very low, and findings should be interpreted cautiously. https://www.crd.york.ac.uk/prospero/, PROSPERO: CRD420261371265.
Borderline intellectual functioning (BIF), defined by intelligence quotient (IQ) scores between 71 and 84, is associated with increased psychiatric vulnerability but remains poorly characterized in terms of clinical severity and treatment complexity. This study aimed to compare psychopathological burden, adaptive functioning, suicidality, and psychopharmacological treatment patterns among hospitalized adolescents with BIF, average intellectual functioning, and intellectual disability. A retrospective chart review was conducted on adolescents aged 12-18 years admitted to a tertiary child and adolescent neuropsychiatry inpatient unit. Participants were classified into three groups based on full-scale IQ. Standardized assessments of cognitive functioning, psychiatric diagnoses, symptom severity, adaptive behavior, global functioning, and suicidality were integrated with clinical indicators derived from medical records, including emergency service utilization and psychotropic medication at discharge. Group differences were examined using nonparametric statistical analyses. The sample included 194 adolescents. Adolescents with BIF showed significantly poorer adaptive functioning across conceptual and practical domains compared with peers with average intellectual functioning, despite comparable global functioning. Overall psychiatric symptom severity at admission and discharge did not differ across groups; however, the BIF group displayed a mixed clinical profile with both internalizing and externalizing symptoms and persistent behavioral dysregulation. Compared with adolescents with average intellectual functioning, those with BIF demonstrated more frequent emergency psychiatric admissions and a higher likelihood of antipsychotic prescription at discharge. Suicidality differed qualitatively across cognitive groups: adolescents with cognitive impairment showed lower rates of suicide attempts, characterized by precipitation (i.e., falling from height) or defenestration (i.e., jumping from a window) as the only suicidal modality observed in this group. BIF in adolescence is associated with a distinct pattern of functional impairment and clinical complexity, characterized by adaptive difficulties and increased reliance on psychopharmacological treatment. These findings highlight the importance of considering cognitive functioning when planning treatment strategies in inpatient child and adolescent psychiatry.