Search Results (80)

The men’s mile world record stood for 27 years before Josh Kerr recorded a provisional world-record time of 3:42.66 in London in 2026, improving Hicham El Guerrouj’s 3:43.13 by only 0.47 s (0.21%). This Perspective examines what changed sufficiently across nearly three decades to advance the observed performance frontier. It argues that the record progression is unlikely to reflect a newly identified physiological determinant or revolutionary training method. The principal requirements of elite mile running, including aerobic power, running economy, oxygen uptake kinetics, anaerobic energy provision, speed reserve, and neuromuscular capacity, were already recognized in the era of the previous record. One plausible interpretation is that contemporary performance systems provide greater opportunities for precision, individualization, and integration in the preparation and expression of established performance determinants. Publicly available accounts of Kerr’s Project 222 illustrate this transition: athlete-specific footwear, race-specific pacing, wearable-derived monitoring, controlled hypoxic exposure, structured recovery, individualized nutrition, and multidisciplinary support were reportedly coordinated around one predefined objective. Available public evidence cannot quantify the contribution of any component or identify a single cause. Kerr’s provisional world-record performance may therefore be interpreted not as evidence of a newly identified physiological determinant, but as an example of how established performance determinants and small refinements in performance support, when systematically aligned, may become meaningful at the extreme end of observed elite performance. Full article

Copper sulfate (CuSO₄) is widely used in industrial and aquatic applications, yet its acute effects on membrane potential and synaptic transmission have not been fully addressed. This study investigated the effects of CuSO₄ on glutamatergic neuromuscular junctions using larval Drosophila melanogaster and Red Swamp Crayfish (Procambarus clarkii) as experimental models. Intracellular electrophysiological recordings were used to measure resting membrane potential, evoked excitatory junction potentials (EJPs), and spontaneous miniature EJPs before and during acute CuSO₄ exposure at multiple concentrations. In larval Drosophila, CuSO₄ produced a rapid, concentration-dependent reduction in both evoked and spontaneous synaptic responses, with higher concentrations nearly abolishing neurotransmission. The co-application of glutamate and CuSO₄ reduced the sustained depolarization produced by glutamate alone, suggesting antagonistic effects on glutamate receptors. CuSO₄ also altered the resting membrane potential, producing significant hyperpolarization at lower concentrations. In contrast, crayfish preparations exhibited enhanced synaptic transmission, with increased EJP amplitudes at higher CuSO₄ concentrations accompanied by membrane hyperpolarization. These findings demonstrate that acute CuSO₄ exposure differentially affects synaptic transmission and membrane potential across model systems, indicating distinct underlying cellular mechanisms. The results suggest that CuSO₄ may influence both glutamate receptor function and ion channel activity, providing insight into the neurophysiological effects of copper toxicity and establishing a foundation for future mechanistic investigations. Full article

Background/Objectives: Hitting the wall (HTW) is a common and performance-limiting phenomenon in marathon running, traditionally attributed to glycogen depletion and reduced carbohydrate availability. However, the persistence of late-race performance collapse despite advances in fueling strategies suggests that HTW may not be explained by a single metabolic mechanism. Instead, HTW may represent a psychophysiological performance-collapse phenomenon arising from the interaction between physiological strain, perceived exertion, pacing regulation, and the athlete’s capacity to preserve function under prolonged stress. Methods: This narrative review aimed to synthesize the physiological and psychophysiological mechanisms contributing to HTW and to propose an integrative durability-based framework for understanding late-race performance deterioration during marathon running. Results: Current evidence indicates that HTW may emerge from the cumulative interaction of metabolic stress, thermoregulatory strain, dehydration, gastrointestinal dysfunction, neuromuscular fatigue, biomechanical deterioration, perceptual responses, and pacing errors. These stressors may progressively increase perceived effort, impair pace regulation, and reduce the athlete’s capacity to preserve physiological function and sustain the intended race pace. Within this framework, durability represents the ability to resist deterioration in physiological characteristics and performance capacity during prolonged exercise and may help explain why runners with similar fitness levels experience different late-race outcomes. Conclusions: HTW should therefore not be viewed simply as running out of fuel. Rather, it may represent the manifestation of reduced durability and psychophysiological dysregulation arising from multiple interacting stressors during marathon running. Strategies aimed at improving durability through marathon-specific training, optimized fueling, gastrointestinal tolerance, thermoregulatory preparation, neuromuscular resilience, pacing regulation, perceptual awareness, and individualized monitoring may reduce susceptibility to HTW. Full article

Muscular fatigue, encompassing both short-term and long-term fatigue, presents a critical challenge in sports like Australian Football (AF) due to its impact on athlete performance and preparation readiness. Within the elite training environment, the intricacies of prolonged neuromuscular fatigue underscore the necessity for practical monitoring methods, like the countermovement jump (CMJ), to comprehend athlete readiness, performance, and the dynamic aspects of player load and positional changes. This research investigates how CMJ performance changes in professional AF athletes during the pre-season and in-season phases, taking into consideration the possible impact of training load and athlete positions. Forty-two elite AF athletes from a professional AF club underwent standardized CMJ testing throughout the pre-season and the first eight matches of the 2023 competitive season. Significant time effects were observed, with a 4% increase in mean jump height among Midfielders from the early to late pre-season, accompanied by a 7% reduction in countermovement depth. Changes in CMJ height performance following the first eight matches were negligible and non-significant; however, variables describing how athletes maintained this performance did substantially change. The study outcomes highlight the need to interpret changes in how any given performance was achieved more closely than an outcome variable alone. Doing so offers insights for targeted training interventions and informed coaching decisions that could assist with optimizing performance throughout the competitive season. Full article

Post-error slowing (PES) is commonly considered a behavioral marker of post-error adaptation. However, adaptive processes may also emerge through subtle modifications of motor preparation, particularly in combat sports such as taekwondo (TKD), where maintaining rapid motor execution is essential. This study examined post-error neuromuscular adjustments during a TKD-specific kicking task by comparing standard Go and post-error Go trials for changes in muscle onset latency, peak electromyographic amplitude, and co-contraction indices. Twenty-eight TKD athletes (14 novice and 14 advanced) performed a sport-specific Go/No-Go task while wearable wireless surface electromyography sensors recorded lower-limb neuromuscular activity from eight lower-limb muscles. Muscle onset latency, peak electromyographic amplitude, co-contraction indices, and reaction time were analyzed using linear mixed-effects models. Post-error Go trials showed significant alterations in muscle onset latency in posterior lower-limb muscles involved in propulsion and movement preparation (semitendinosus, biceps femoris, lateral gastrocnemius, and soleus), with muscle activation occurring closer to the foot take-off. No significant differences were observed in reaction time, peak electromyographic amplitude, or co-contraction indices, and expertise and age did not modulate these effects. These findings suggest that error-related motor adjustments may be expressed through changes in muscle activation timing rather than overt behavioral slowing. Full article

This case report documents the multi-season development of a 38-year-old elite F12 shot putter with macular degeneration (<10% functional vision) who improved from 13.00 m to a personal best of 14.41 m between 2021 and 2023. Athletes classified as F11–F13 compete with significant visual impairment that limits spatial feedback during rotational tasks, yet longitudinal evidence describing integrated training frameworks remains scarce. A 12-month macrocycle integrated phase-dependent velocity-based resistance training using mean concentric velocity targets (0.70–1.00 m·s⁻¹) monitored via linear position transducers with a 10% velocity loss threshold, combined with structured auditory and tactile cueing, including metronome pacing and environmental anchors. High-volume warm-ups and prehabilitation addressed a prior L4–L5 disk herniation. The athlete achieved 14.41 m at the 2023 U.S. Para Athletics Trials, with TrackMan^®-verified release velocity of 11.3 m·s⁻¹. Bench throw velocity improved by 35.4% (0.65 to 0.88 m·s⁻¹) and squat jump velocity improved by 22.9% (1.18 to 1.45 m·s⁻¹), while post-session RPE remained manageable, indicating improved neuromuscular readiness and training tolerance. No lumbar symptom recurrence occurred. This case illustrates that integrating velocity autoregulation, multisensory stabilization, and injury-informed preparation can support meaningful performance gains in visually impaired throwers and offers an applied framework for coaches working with F11–F13 athletes. Full article

The purpose of this narrative review was to describe the maximal strength, muscle power, rate of force development, and muscle morphology of athletes across different ski disciplines. Specifically, this review synthesizes evidence on upper- and lower-body maximal strength both dynamically and isometrically, muscle power through jumping performance and rate of force development, and muscle morphology in competitive skiers. Furthermore, it examines how these neuromuscular parameters adapt when resistance-training interventions are incorporated into athletes’ routine training programs. Following a literature search, 30 studies met the inclusion criteria, 18 describing the ski athletes’ characteristics mentioned above and 12 evaluating the effects of resistance-training interventions. Altogether, these studies involved 561 participants, with ages ranging between 14.6 ± 1.1 years and 35 years. Overall, the above characteristics of ski athletes appear to align with sport-specific demands, which vary across ski disciplines. The resistance-training protocols applied in this population are predominantly high-load resistance training and it appears that resistance training may benefit from increased emphasis in ski-specific preparation. However, training programs tailored to the specific demands of each discipline are recommended. Full article

Flexor hallucis longus (FHL) tendon injuries, although rare, severely affect foot stability and mobility, particularly in individuals engaging in repetitive push-off actions. This case study examines a 27-year-old male who underwent surgical repair for FHL tendon rupture, followed by a structured, multi-modal rehabilitation program integrating advanced therapeutic techniques. The 12-week program was divided into three distinct phases to ensure a structured and progressive recovery process. The Early Phase (Weeks 1–4) focused on pain and edema control through interventions such as massage, electrotherapy, kinesiotaping, and the use of peritendinous ultrasonography to monitor recovery progress. The Intermediate Phase (Weeks 5–8) aimed to enhance strength and flexibility by incorporating Proprioceptive Neuromuscular Facilitation (PNF), weight-bearing exercises, dynamic stretching, and the progressive integration of Graston massage techniques. Finally, the Advanced Phase (Weeks 9–12) prioritized functional recovery, utilizing balance training, load transfer exercises, agility drills, and Theragun applications to prepare the individual for a return to optimal physical performance. Significant improvements were observed, including pain reduction (VAS score reduced by X%), increased dorsiflexion flexibility (from X° to X°), and enhanced muscle strength (e.g., tibialis anterior strength increased by X%). Functional assessments, such as the Y Balance Test, revealed improved endurance and mobility. This case study highlights the benefits of integrating innovative techniques like Graston massage and Theragun within a structured, evidence-based rehabilitation program to optimize recovery post-FHL tendon surgery. Full article

Optimizing neuromuscular strength and balance is essential for performance and injury prevention in elite Paralympic sport. However, limited evidence describes how these parameters change over time during specific phases of the training season in athletes with lower limb deficiencies. This retrospective case series aimed to describe longitudinal changes in neuromuscular and balance performance during the fundamental preparation period in elite athletes using prosthetic devices. Routinely collected performance data from five international-level Paralympic athletes (Para-swimming and Para-athletics) were retrospectively analyzed across two preparatory observation windows conducted in consecutive competitive seasons. Neuromuscular performance was assessed using countermovement jump variables, while static balance was evaluated through Inertial Measurement Unit-derived sway metrics. Within-athlete changes were examined using descriptive and exploratory analyses. At the group level, changes were observed in selected neuromuscular and balance outcomes over time, including jump height and path length. Individual analyses revealed substantial inter-athlete variability in the magnitude and direction of changes across all outcomes. Overall, the findings indicate that neuromuscular and postural performance may fluctuate meaningfully during preparatory phases in elite athletes with lower limb deficiencies. This study provides exploratory insights derived from real-world training settings and highlights the value of longitudinal monitoring to support individualized performance management in Paralympic sport. Full article

(1) Background: Military personnel are required to perform high-intensity actions and tactical tasks under external load, which increases system weight and alters movement mechanics. Understanding how these loaded conditions influence neuromuscular performance is essential for informing physical preparation and readiness monitoring. This study quantified the effects of tactical equipment on countermovement jump (CMJ) and countermovement rebound jump (CMRJ) force–time characteristics in active military personnel and evaluated the within-session reliability of these metrics under loaded and unloaded conditions; (2) Methods: Eighteen male soldiers performed CMJ and CMRJ assessments on dual force plates (1000 Hz) under unloaded and loaded conditions (standardized tactical equipment: 10.6 ± 1.18 kg). Force–time variables were categorized as strategy (phase durations, countermovement depth), driver (mean braking and propulsive force), and outcome (jump height, jump momentum, and modified reactive strength index; mRSI) metrics; (3) Results: CMJ outcome and driver metrics demonstrated good to excellent reliability under load (ICC ≥ 0.87; CV ≤ 8.4%), whereas CMRJ outcome variables showed reduced reliability and greater variability. Loaded conditions reduced jump height and mRSI in both CMJ and CMRJ (p < 0.05), while jump momentum and absolute mean force production increased, whereas force production relative to body mass decreased. During the CMJ (slow-SSC), participants exhibited longer braking and propulsive phase durations, indicating a temporal change in movement strategy under load, whereas CMRJ (fast-SSC) force–time characteristics showed increased contact time and reduced rebound metrics; (4) Conclusions: Overall, fast stretch–shortening cycle tasks appear more sensitive to loading conditions, whereas the CMJ provides a more robust and reliable assessment for monitoring neuromuscular performance in military personnel, particularly when considering both absolute and relative force responses. Full article

Background/Objectives: The front kick is among the most commonly used techniques in martial arts. This study aimed to analyze the range of motion during the mae-geri kick in advanced-level Kyokushin karate practitioners compared to an intermediate-level control group under three conditions: before warm-up, after warm-up, and after a shadow fight. Methods: The study group [N = 28, M: 27.6 years, body mass 81.9 kg, height 1.8 m] consisted of advanced-level Kyokushin karate practitioners (3rd kyu and higher), and the control group consisted of intermediate-level practitioners (6th to 4th kyu). A wireless surface electromyography (EMG) system was used to record muscle activity and an inertial measurement unit (IMU) was used to measure joint angles. Before the study began, the maximum voluntary contraction was determined for each muscle tested. Each participant performed three consecutive kicks in three conditions: before warm-up, after warm-up, and after a shadow fight. Results: The intermediate-level practitioners used the soleus muscle more than advanced practitioners during the front kick (48.92% vs. 35.94% before the warm-up kick, p = 0.042, η²_p = 0.27). After the warm-up, both groups began to use the soleus muscle more intensively (intermediate: 48.92% vs. 61.72% MVC, p = 0.046; advanced: 35.94% vs. 48.69% MVC, p = 0.045), and the advanced group’s activity in the medial gastrocnemius muscle increased compared to before the warm-up (58.23% vs. 39.20% MVC, p = 0.016). Conclusions: Advanced vs. intermediate Kyokushin karate practitioners display distinct neuro-muscular activation strategies in the mae-geri kick, particularly in soleus and gastrocnemius recruitment. Combined EMG and IMU systems can identify trends and in-form training feedback in Kyokushin karate training and effectively prepare the musculoskeletal system for rapid activity, which is important during sports competitions. Full article

Background/Objectives: Knee osteoarthritis (KOA) is associated with pain, functional decline, and altered biomechanics. The Step-Up and Down-Forwards (StUD-F) task provides an ecologically relevant assessment of challenging movements. This study investigated neuromuscular activation and lower-limb kinematics of leading and trailing-limbs during the StUD-F in individuals with KOA. Methods: Forty participants with KOA (65.3 ± 7.68 years; 21M/19F; BMI 28.9 ± 4.52 kg/m²) completed a 25 cm box StUD-F task. Surface electromyograph recorded bilateral activation of the vastus medialis (VM), vastus lateralis (VL), bicep femoris (BF), and semitendinosus (ST). Triplanar hip, knee, and ankle joint angles were estimated using inertial measurement units. StUD-F events (initial stance; step contact; ascent completion; descent preparation; step-down touchdown; and descent completion) were identified using custom algorithms. Pain was assessed using visual analogue scales and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Limb differences were analysed for leading or trailing roles using paired samples t-tests or non-parametric equivalents; waveforms were visually inspected. Results: Distinct neuromuscular and kinematic asymmetries were observed when affected and contralateral limbs were compared within each role (leading/trailing). During step-up, the affected leading limb demonstrated higher quadriceps activation at initial stance (VM: p = 0.035; VL: p = 0.027) and reduced trailing-limb activation at step contact (VM: p = 0.015; VL: p = 0.018), with sagittal-plane ankle differences (p = 0.004). During step-down, when the affected limb initiated ascent, trailing limb activation was higher at descent completion (VL: p < 0.001; VM: p = 0.003; BF: p = 0.009), with coronal-plane hip deviations (p < 0.001). When the contralateral limb-initiated ascent, trailing-limb muscles activation differences (VM: p < 0.001; VL: p = 0.015; BF: p = 0.007) and ankle/coronal-plane asymmetries (p ≤ 0.049) persisted. Conclusions: The StUD-F task elicits altered strategies in KOA, including elevated quadriceps–hamstring co-activation and altered sagittal/coronal alignment, and habitual limb choice across ascent and descent. These adaptations may enhance stability and joint protection but could increase medial compartment loading. The findings support rehabilitation focused on dynamic control, alignment, and shock absorption. Full article

Hand rehabilitation in neurologic conditions such as stroke and cerebral palsy traditionally emphasizes repetitive task practice with visually observable feedback, despite motor impairment arising largely from abnormal neuromuscular activation. We present a platform that leverages noninvasive measurements of brain and muscle activity for neurofeedback-guided movement training. Trainees first learn to control EEG during movement preparation, followed by reciprocal control of finger muscle EMG during exoskeleton-assisted movement. We describe the platform design and two feasibility studies. Five neurotypical individuals learned to use EEG and EMG to drive an exoskeleton to grasp and release a virtual ball in a single session. They achieved a mean success rate of 65%, demonstrating improved movement latency (9%) and task completion time (6%) across the session. One individual post-stroke trained with the platform across eight sessions and exhibited improvements on the Box and Blocks Test, the Action Research Arm Test, and the Wolf Motor Function Test. These results demonstrate the feasibility of multi-level, neurofeedback training that targets neural activation throughout movement, rather than movement outcome alone. By explicitly engaging both cortical and muscular control signals, this paradigm offers a promising new direction for hand rehabilitation following neurologic injury. Full article

Foodborne botulism is a potentially fatal disease caused by Clostridium botulinum neurotoxins (BoNTs). These spore-forming bacteria are ubiquitous in the environment and can contaminate various food products, especially raw vegetables. During the preparation of home-made preserves, favorable conditions of anaerobiosis, temperature, salinity, and pH can lead to spore germination and toxin production. BoNTs can reach neuromuscular junctions where they block the release of acetylcholine. In this study, we present a case of foodborne botulism associated with the consumption of chili peppers preserve containing BoNT/B. The isolated strains were characterized through Whole Genome Sequencing, confirming the strains involved in the outbreak. This work increases the understanding of the epidemiology and the ecology of C. botulinum, highlighting the importance of raising medical awareness and making timely clinical diagnoses for the effective management of botulism outbreaks. Full article

Risdiplam is the first approved small-molecule therapy for spinal muscular atrophy (SMA), a severe, progressive neuromuscular disorder. In addition to its clinical significance, risdiplam is of a great interest for organic and medicinal chemistry due to its complex molecular architecture. Its structure incorporates three highly substituted heterocyclic fragments—imidazo[1,2-b]pyridazine, pyrido[1,2-a]pyrimidin-4-one, and 4,7-diazaspiro[2.5]octane—that serve as both versatile synthetic building blocks and critical pharmacophoric elements for drug design and discovery. The increasing scientific interest in risdiplam has led to numerous publications and patent applications that describe alternative synthetic methodologies. Recently, our group has also developed and introduced efficient, scalable manufacturing routes for the preparation of the target substance and the key intermediates of its synthesis. This mini-review systematically analyzes a plethora of risdiplam assembly strategies and synthetic approaches, covering developments from 2013 to the present. Full article