Endurance sports are characterized mainly by prolonged exercise demands. Although endurance performance is primarily supported by aerobic metabolism, anaerobic energy pathways, buffering capacity, neuromuscular resilience, and the ability to tolerate fatigue during decisive moments of a race are also relevant to competitive success. In this context, creatine and beta‐alanine supplementation are two ergogenic strategies purported to enhance endurance performance. This review critically examines the physiological rationale and current evidence regarding creatine supplementation, beta‐alanine supplementation, and their cosupplementation in endurance sports. The available literature suggests that beta‐alanine may improve performance in exercise tasks performed in the aerobic–anaerobic transition zone, through increased skeletal muscle carnosine content and enhanced intracellular buffering capacity. Creatine supplementation may support endurance performance by increasing phosphocreatine availability, improving glycogen resynthesis and buffering capacity, attenuating exercise‐induced inflammation and muscle damage, preserving fast‐twitch muscle characteristics, and enhancing repeated sprint ability or late‐race power output. However, evidence supporting improvements in classical markers of aerobic performance, such as VO 2 max, lactate threshold, and time‐to‐exhaustion, remains inconsistent, and the available evidence has been derived from untrained or recreationally active individuals, limiting direct translation to highly trained endurance athletes. Therefore, the practical relevance of these supplements appears to depend on the athlete’s training phase, event characteristics (e.g., weight‐bearing or not), competitive goal, and performance level. Creatine and beta‐alanine should not be viewed as universal ergogenic aids for endurance athletes, but rather as targeted nutritional strategies that may be particularly useful in race contexts where repeated high‐intensity efforts, fatigue resistance, and decisive finishing actions influence performance.
During exercise, rising metabolic heat production creates competition for blood flow between skeletal muscle and the cutaneous vasculature. The resulting redistribution elevates cardiovascular (CV) strain and accelerates fatigue, particularly during environmental heat stress or in individuals with impaired thermoregulatory capacity. Strategies that enhance heat dissipation without further burdening CV function may therefore improve exercise tolerance. Palmar cooling (PC) is an intervention that targets the glabrous skin of the hands, where dense arteriovenous anastomoses facilitate high‐flow, low‐resistance blood flow and efficient convective heat exchange, thereby augmenting systemic heat dissipation through the peripheral circulation. Evidence in healthy and athletic populations suggests that PC can decrease thermal strain while improving endurance capacity, resistance training volume, and perceptual responses when applied under meaningful heat stress, although current findings remain heterogeneous. Given age‐ and disease‐related reductions in thermoregulatory and CV reserve, PC may have translational relevance for enhancing exercise tolerance during rehabilitation, reducing heat‐related illness risk, and supporting individuals with cardiopulmonary disease. Improved within‐session tolerability may, in turn, facilitate greater cumulative training stimulus and adherence, with potential downstream benefits for overall exercise capacity. This narrative review discusses the thermoregulatory, CV, and exercise physiology underlying PC, evaluates the current evidence, and outlines future directions to support clinical translation.
Background Youth football players experience a high incidence of injuries, particularly apophyseal injuries in the lower extremities. However, the prevalence and characteristics of these injuries in male adolescent academy players remain inadequately documented. Objective To investigate the prevalence, incidence, and characteristics of apophyseal injuries in the lower extremities among male adolescent academy football players over one season. Design One‐season prospective cohort study. Participants Fifty‐eight Norwegian male adolescent academy football players (aged 12–19 years) were investigated during the 2022 football season. Methods Weekly self‐reports of health problems were collected using the Oslo Sports Trauma Research Center Questionnaire on Health Problems (OSTRC‐H2). Clinical examinations were performed to diagnose apophyseal injuries. Results The average weekly prevalence of self‐reported health problems was 37%, while the average weekly prevalence of clinically diagnosed apophyseal injuries in the lower extremities was 12%. The incidence rate for these injuries was 4.6 per 1.000 h of exposure. Pubic apophysitis was the most common injury (32% of diagnosed cases). Most injuries (77%) had a gradual onset, with 81% occurring during or directly after training sessions. Conclusions Apophyseal injuries represent a significant health problem in male youth football players, with pubic apophysitis being the most prevalent condition. These findings highlight the need for improved awareness, early detection, and targeted injury prevention strategies in youth football.
Purpose The aim of this study was to investigate the acute effect of different active resisted sprint loads upon joint kinematics and leg electromyography (EMG) activity in experienced sprinters. Methods Thirteen experienced male sprinters (age: 20.5 ± 1.3 years, body mass: 66.8 ± 4.5 kg and body height: 1.74 ± 0.06 m) with best 100‐m times of 11.24 ± 0.34 s performed a 50‐m sprint with maximal effort from three‐point start. Afterwards, they performed different resisted sprints with maximal effort provided by a robotic pulley system that resulted in 65%, 50%, 25% and 10% reduction of peak velocity for, respectively, 10, 20 and 30 m in randomised order while spatiotemporal parameters, joint kinematics and EMG of nine leg muscles were measured from the point which sprint velocity plateaued. Results The main findings were that increasing velocity‐decrement conditions resulted in reduced sprint velocity, shorter step length, lower step frequency and prolonged ground contact time together with joint kinematics changing to a more flexed posture and forward leaning at touch down and less extension at toe off, with lower, maximal angular velocities during contact times. These adaptations resulted in more quadriceps dominant activity with increased stabilizing activity of gluteus medius, while hamstring activity decreased due to the lower angular knee extension during flight times with increasing resisted loads. Conclusion This study suggests that while resisted sprinting is an effective tool for increasing force production demands, higher resisted loads (> 50% velocity decrement) are associated with progressively different kinematic and neuromuscular patterns, likely reflecting the combined effects of increased force demands and thereby reduced running velocity.
Expertise in high‐stakes occupations is typically evaluated through performance outcomes, potentially neglecting physiological efficiency—a dimension critical for career longevity in physically demanding work. In this pilot study, we investigated whether expert firefighters achieve comparable task performance with lower cardiovascular activation and faster autonomic recovery than novices during realistic search‐and‐rescue operations. Twenty‐two male firefighters completed navigation tasks in a high‐fidelity training facility under operational conditions (complete darkness, full protective equipment). Using a 2 × 2 quasi‐experimental design, we manipulated navigation strategies (route‐based vs. survey‐based) and continuously recorded heart rate variability across baseline, execution, and recovery periods. Our preliminary data suggest that behavioral outcomes and physiological responses may be largely decoupled in this context. Experts and novices demonstrated equivalent task completion times and accuracy. However, experts exhibited substantially lower heart rate elevation during tasks and 46% greater parasympathetic recovery post‐task. Critically, an expertise‐by‐strategy interaction suggested that experts’ efficiency advantages were magnified when employing route‐based strategies aligned with training protocols, whereas novices showed no strategy‐dependent differences. These findings provide preliminary evidence that physiological efficiency represents a distinct expertise component, suggesting that identical overt performance can mask vastly different internal costs. Heart rate variability monitoring may therefore serve as a useful exploratory tool to help identify individuals requiring additional skill consolidation or recovery support before overt performance degrades.
