The menstrual cycle can influence a range of physiological and psychological processes that may affect physical performance. However, existing evidence is inconsistent and often based on isolated testing timepoints rather than typical training conditions. Monitoring kinematic outputs during resistance training allows quantification of day-to-day performance changes.

This study evaluated whether kinematic outputs during resistance training vary across menstrual cycle phases over two mesocycles and explored associations with symptoms, and perceived motivation and readiness.

This study was conducted at Australian Catholic University (Brisbane, Australia) between February 2023 and June 2025 and was registered with the trial number ACTRN12626000365369. Twenty-eight resistance trained females (mean ± SD; age: 27.1 ± 5.2 years) completed two mesocycles of supervised resistance training. Across the intervention, menstrual cycles were monitored using calendar-based counting, urinary ovulation tests, and retrospective serum 17β-estradiol and progesterone concentrations. Three-repetition maximum (3RM) and load–velocity profiles (LVPs) for the bench press and trap bar deadlift were assessed at baseline, mid training (~4 weeks), and post training (~8 weeks). During each training session, kinematic outputs were recorded for all repetitions, with the fastest repetition from each set used to assess training performance across menstrual cycle phases and the observed velocity compared to the expected velocity from the LVP. Symptoms, perceived motivation, and readiness were reported at the start of each resistance training session.

Significant differences in observed versus expected average peak mean velocity were found in the bench press during phases 1 and 5, and in the deadlift during phases 1 and 6. For both exercises, observed versus expected average peak mean velocity differed by ~ 0.01–0.02 m·s⁻¹ across menstrual cycle phases. After multivariate modeling, motivation to train was a strong predictor of training performance (β = 0.0004, p = 0.021), whereas readiness to perform was not. The symptom domain pain was positively associated with bench press performance (0.00065 m∙s⁻¹ per unit change; p = 0.018), whereas pain was negatively associated with deadlift performance (− 0.001 per unit change; p < 0.001). Additionally, no significant main effect was found for the symptom domain control, but a between-exercise difference was found (p < 0.03). No other symptom domains showed significant relationships with training performance.

Menstrual cycle phase appears to have minimal effect on resistance training performance, with kinematic outputs demonstrating modest differences compared to what would be expected. Consequently, these findings support consistent resistance training across the menstrual cycle, without the need for phase-based adjustments to maintain performance. However, motivation and symptom profiles may influence resistance training across the menstrual cycle.

Understanding the acute demands of short-bout high-intensity interval training can enhance training outcomes.

We aimed to examine the acute physiological and perceptual demands of short-bout high-intensity interval training in athletes and identify how they are moderated by programming variables, fitness level and competitive level.

We searched the databases PubMed, SPORTDiscus and CINAHL on 2 December, 2025 for original research articles investigating running-based, short-bout high-intensity interval training in healthy athletes, aged 16–40 years, of any sex, who were recreationally active or above. Outcomes were analysed using a multi-level mixed-effects meta-analysis. The analysed outcomes were: average heart rate (HR_avg), peak heart rate (HR_peak), peak and average oxygen consumption (VO₂), time > 90% of maximal oxygen consumption (T > 90% VO_2max), time > 95% of VO_2max (T > 95% VO_2max), T > 90% VO_2max/exercise time ratio (T₉₀/ET), T > 95% VO_2max/exercise time ratio (T₉₅/ET), blood lactate concentration (B[La]) and session ratings of perceived exertion (sRPE). To examine the influence of programming variables, fitness level, and competitive level, a meta-regression was performed on moderators with ten or more samples. Effects were evaluated based on coverage of their confidence limits against elected thresholds of practical importance.

From 139 data samples within 46 studies, the pooled demands (± 90% confidence limit) of short-bout high-intensity interval training were: HR_avg, 169 ± 4 b·min⁻¹ and 88 ± 2% of maximum heart rate; HR_peak, 184 ± 4 b·min⁻¹ and 94 ± 2% of maximum heart rate; average VO₂, 46 ± 3 mL·kg⁻¹·min⁻¹ and 78 ± 4% of velocity at VO_2max; peak VO₂, 55 ± 5 mL·kg⁻¹·min⁻¹ and 93 ± 7% of VO_2max; T > 90% velocity at VO_2max, 259 ± 57 s; time > 95% VO_2max, 125 ± 48 s; T₉₀/ET, 0.34 ± 0.9; T₉₅/ET, 0.15 ± 0.07; B[La], 8.3 ± 0.5 mmol·L⁻¹; and sRPE, 7.1 ± 0.5 au. When compared to an athlete VO_2max of 50–55 mL·kg⁻¹·min⁻¹, a VO_2max of 55–60 mL·kg⁻¹·min⁻¹ and > 60 mL·kg⁻¹·min⁻¹ were associated with a substantial decrease in sRPE (− 1.7 ± 1.3 au and –1.6 ± 1.1 au, respectively). Compared to a reference protocol of 1 set of 12 straight-line repetitions, performed at 120% of maximal aerobic speed for a 15-s work duration with 15 s of passive rest: shuttle runs were associated with a substantial increase in B[La] (1.9 ± 1.0 mmol·L⁻¹) and sRPE (1.7 ± 0.4 au); active rest was associated with a substantial increase in T₉₀/ET (0.21 ± 0.11); performing a 15-s longer repetition was associated with a substantial increase in T > 90% velocity at VO_2max (160 ± 113 s); completing one more set was associated with a substantial increase in B[La] (1.2 ± 0.1 mmol·L⁻¹); and a 5% increase in maximal aerobic speed was associated with a substantial increase in B[La] (1.0 ± 0.3 mmol·L⁻¹), HR_avg (3.2 ± 1.4 b·min⁻¹), and T₉₀/ET (0.05 ± 0.04), but a substantial decrease in T > 95% VO_2max (− 44 ± 28 s). All other moderators had compatibility with trivial effects or were inconclusive.

Short-bout high-intensity interval training elicits a substantial physiological stimulus, which is influenced by programming variables, athlete fitness level and competitive level. Implementing an active rest period, longer repetition duration and a higher running intensity are effective strategies to maximise the aerobic stimulus, while shuttle runs increase the anaerobic demand.

In endurance athletes, cardiovascular oxygen delivery is the primary limitation to performance. While the focus of athletes and regulatory bodies has been on hemoglobin and red blood cells, the increased oxygen-delivering capacity resulting from training is also a consequence of the expanded blood volume, which requires vascular adaptation. Angiogenesis—the formation of new blood vessels from pre-existing ones—is an understudied area in exercise physiology due to the need for invasive procedures. Among the vascular endothelial growth factors, VEGF-A and VEGF-D are the most potent angiogenic inducers and thus candidates for doping purposes. VEGF expression can be stimulated by several external factors, of which oxygen deprivation and its mimics are the most significant in the context of doping. A controlled overexpression of VEGF-A or VEGF-D, and the resulting blood vessel formation, could directly increase vascular space and indirectly increase blood volume and athletic ability. A master regulatory gene such as HIF-1α would be a preferred target over any single growth factor, as it would affect red blood cell production and vascular expansion synchronously. Currently available compounds may already be misused, with potential unintended consequences, including the aggravation of inflammatory diseases or tumor progression. Due to the ease of implementation and difficulty of detection, angiogenic doping and possible detection strategies deserve to be studied further.

Current physical activity guidelines for pregnancy recommend avoiding climbing owing to the increased risk of falling, which are based on opinion owing to limited empirical data. This cross-sectional study examined climbers’ perceptions of climbing during pregnancy, safety, falls, exposure of climbing during the pregnancy and postpartum period, and the impact of participation in climbing during pregnancy has on maternal and fetal health outcomes.

Climbers aged ≥ 18 years completed an online questionnaire between May and October 2024 based on the pregnancy where they had the highest engagement in climbing. Questions related to maternal demographics, training and competition patterns, health outcomes during and following pregnancy, and returning to climbing postpartum. Hard falls were subjectively defined as falls or catches that were hard enough to remember/cause concern.

Overall, 692 participants (34.7 ± 3.8 years) completed the survey. Respondents were primarily located in the USA (34.2%), Germany (14.1%), and the UK (13.3%). The cumulative total of falls between participants was 155 across 63,972 h of climbing. Rates of adverse events was 0.03 per 1000 h of exposure. While most participants had concerns about climbing during their pregnancy, 96% felt “happy” or “very happy” that they continued to climb. Mental and emotional health outcomes were improved or unchanged by those who continued to participate. There was no significant difference in pregnancy health outcomes between groups who stopped climbing ≤ 27 weeks gestation and those who continued to climb. Participants returned to climbing at 2.7 months postpartum.

Continued participation in climbing into the third trimester was not associated with increased odds of self-reported pregnancy complications.

Despite undertaking large volumes of structured exercise training, evidence suggests that masters athletes (MAs) remain susceptible to coronary artery disease (CAD). This review evaluated the prevalence and nature of CAD in MAs.

PubMed, Medline, EMBASE, Web of Science and Cochrane Library were searched on 23 November 2024, from 1 January 2000. MAs were defined as apparently healthy individuals aged ≥ 35 years with an exercise training history indicative of regular engagement in sporting activity. The Appraisal tool for Cross-Sectional Studies (AXIS) was used to assess study quality.

A total of 17 studies reporting various measures of CAD in 2749 MAs (2127 male, 622 female) were included. Coronary artery calcium (CAC) was present in a significant proportion, with 565 MAs scoring > 0, and 179 and 43 MAs exceeding thresholds of > 100 and > 400, respectively. Evidence of plaque was detected in at least 458 MAs. This was predominantly calcified in the majority of cases. Obstructive disease (> 50% stenosis) was also identified in at least 51 MAs. Conventional cardiovascular (CV) risk factors such as smoking, dyslipidaemia, hypertension and diabetes were prevalent in this population.

Clinical and methodological heterogeneity made it challenging to perform accurate quantitative analyses. However, our data reiterate that MAs are not invulnerable to CAD. Long-term and high-intensity endurance training may be associated with changes that predispose to atherosclerotic disease. Female MAs, and those from low- and middle-income countries, are markedly underrepresented in literature.

A more individualised approach to CV risk assessment may be warranted in the future to guide early CAD detection and subsequent management.

PROSPERO 2024 CRD42024607539.

Anterior cruciate ligament (ACL) rupture is a serious sporting injury associated with impaired performance, high recurrence rates, early-onset knee osteoarthritis and substantial health and economic burden. In Australia, ACL injury incidence has increased over the past two decades, with particularly high rates observed among female and adolescent athletes participating in cutting and landing sports. Neuromuscular and structured warm-up programs can reduce ACL injury risk; however, implementation and adherence remain inconsistent, and evidence for effectiveness in males, elite athletes and several high-risk sports is unclear. Practitioners, therefore, require clear, evidence-based guidance to prescribe effective prevention strategies across diverse populations. This position statement provides contemporary, evidence-informed recommendations to guide exercise prescription for ACL injury prevention by (1) critically evaluating the effect of existing exercise interventions on ACL injury incidence, and (2) synthesising evidence on intrinsic risk factors and mechanistic pathways for non-contact ACL injury to inform targeted training strategies. Two systematic literature searches were conducted in Scopus, Embase and PubMed. The first identified randomised and non-randomised controlled trials and cohort studies evaluating the effect of exercise-based interventions on ACL injury incidence. The second identified prospective studies examining intrinsic risk factors for non-contact ACL injury. Evidence on ACL injury aetiology was synthesised by integrating injury risk factors, video analyses of injury events, in vivo and in vitro laboratory studies and in silico biomechanical modelling. We propose a tiered framework for exercise prescription. Tier 1 strategies emphasise population-level neuromuscular and structured warm-up programs, which meta-analyses indicate can reduce ACL injury risk by approximately 60% in adolescent female soccer, basketball and handball players. Effective programs typically combine plyometric, strength, balance/proprioception, mobility and agility exercises performed for 10–30 min, 2–3 times per week. Tier 2 strategies target specific neuromuscular deficits or high-risk movement patterns, including low knee flexion, dynamic knee valgus, lateral trunk flexion and excessive step width. Interventions may include plyometric and resistance exercises, motor control drills and neurocognitive challenges to increase transfer to game scenarios; however, direct evidence linking Tier 2 strategies to reduced injury incidence remains limited. This position statement provides an evidence-based framework to support the design and practical implementation of effective ACL injury prevention strategies in sport. 

Exposure to environmental stressors such as hypoxia or heat has emerged as an effective strategy to stimulate physiological adaptations, enhance sport/physical performance and promote health. Both environmental stressors activate shared molecular pathways, notably through the stabilisation of hypoxia-inducible factor-1 alpha and the induction of heat shock proteins, which mediate cellular protection and systemic molecular adaptation. However, hypoxia and heat differ in several aspects, including induction modalities, monitoring methods, metrics used to assess physiological strain and substantial intra- and inter-individual variability. Together, these differences challenge direct comparison and/or combination. Therefore, this current opinion highlights research gaps by critically presenting the common and distinct physiological responses and adaptations to hypoxia and heat exposure. It also emphasises the importance of monitoring internal physiological strain rather than external environmental stress to better account for individual variability. Finally, we propose future research perspectives to address current methodological challenges.

Running biomechanics has long questioned whether a universally optimal running pattern exists. Current evidence indicates that no single technique is optimal for all individuals. Instead, runners self-optimize their movement according to anatomical structure, neuromuscular capacity, experience, and environmental constraints. This narrative review first examines the diversity of running patterns and the concept of self-organization, emphasizing that multiple biomechanical configurations can yield comparable running economy when aligned with individual characteristics. We then analyze how biomechanical models represent human locomotion. The spring–mass model explains key features of high-speed, elastic-driven running but becomes progressively limited as speed decreases. Actuator-based models incorporating active work and dissipation provide a more comprehensive account of endurance locomotion. From this modeling perspective, running mechanics are interpreted as a speed-dependent continuum from elastic-driven strategies at sprinting speeds to more muscle-driven strategies at slower speeds. Running speed is identified as the primary independent variable structuring these trends, while individual responses introduce variability around group-level norms. Translating this framework into practice requires individualized assessment rather than prescriptive technique modification. We present the PIMP method (Preferred running form assessment, Identification of inefficiencies in vertical load management, and Movement Plan individualization) as a structured approach to intervention. Central to this framework is the “Mind to Move” principle, in which outcome-focused imagery promotes biomechanical coherence between intrinsic capacities and external demands. The bouncy spring metaphor reinforces short elastic actions, whereas the rolling wheel metaphor supports prolonged, muscle-driven efforts. Performance optimization thus depends on context-sensitive, individualized strategies rather than replication of idealized forms.

The purpose of this statement is to guide the design and conduct of high-quality sport and exercise science studies investigating the effects of varied ovarian hormone profiles on the health and athletic performance of elite female athletes. Beyond the menstrual cycle, these athletes present with a wide range of ovarian hormone profiles, including those associated with puberty and menarche, menstrual dysfunction, hormonal contraceptive use, pregnancy and postpartum, perimenopause, menopause and post-menopause. To effectively integrate knowledge of ovarian hormone profiles into high-performance sport and address the diverse needs of female athletes, future research and educational initiatives must encompass this broader spectrum of ovarian hormone profiles. However, to produce this knowledge, improvements in research design and conduct are necessary and can be facilitated by adopting reporting checklists as a structured approach to enhance transparency and reproducibility. We recommend that such quality assurance measures be integrated at the study design phase, along with clear research questions, appropriate study designs, and valid analysis methods. Consequently, the proposed guidelines aim to support researchers working in applied settings with elite female athletes in generating more robust and impactful evidence.

This study aimed to identify the Greatest of All Time (GOAT) athlete in running events held at the Olympic Games and World Athletics championships.

The achievements of 1294 men and 824 women who won at least one medal in any sprint, hurdles, or distance event at major global championships since 1896, or set a World Record (WR) since 1912, were collated. A scoring system was used to award points, with Olympic gold medals and WRs ranked joint highest. Fewer points were awarded for Olympic silver and bronze medals and for medals in World Championships (outdoor, indoor, and cross-country). Bonus points were awarded for WR longevity and the setting of WRs during Olympic finals. Athletes were also ranked by event and within historical eras.

As of March 2026, Usain Bolt (Jamaica) was ranked as the male GOAT, and the highest-scoring woman was Faith Kipyegon (Kenya). Both athletes notably won “doubles” during their careers (over 100/200 m and 1500 m/5000 m, respectively) and set WRs over both distances. Marathon, steeplechase, and hurdle specialists usually competed in one event only. In an earlier era, Paavo Nurmi (Finland) had the highest combined Olympic Games/WR score across a range of distances.

Athletes who successfully competed over physiologically and tactically similar events (“doubles”), such as Bolt and Kipyegon, had a greater opportunity to become the GOAT. An increase in global competition since 1972 meant greater opportunities for winning medals, especially for women. This study provides a foundation on which future performances could be evaluated.

Athletic injury has previously been defined as tissue damage or other derangement of normal physical function due to participation in sports, resulting from rapid or repetitive transfer of kinetic energy. Alternatively, athletic injury has also been described as occurring when the stresses and strains experienced by a tissue result in damage severe enough to be considered an athletic injury. In mechanical models quantifying damage and the accumulation of damage over time, damage is commonly represented using a damage variable (D) ranging between 0 and 1, where D = 0 corresponds to an undamaged state and D = 1 corresponds to complete mechanical failure. Adopting this approach, a mathematically deterministic definition for athletic injury can be established, allowing precise predictions of athletic injury occurrence in mathematical models. Specifically, an athletic injury can be mathematically defined as occurring when the damage (D) experienced by a tissue exceeds a critical damage threshold (D_c), that is, D > D_c, with complete tissue failure occurring at a damage variable of 1. Alternatively, athletic injury can also be mathematically defined as an applied mechanical load (L) exceeding a critical tissue strength threshold (S_c), that is, L > S_c, with complete tissue failure occurring when L > failure strength (S_f). While determinism is valuable for establishing a precise definition of athletic injury for mathematical models, in practice, probabilistic models are needed to account for the inherent variability and uncertainty in estimating the primary variables determining athletic injury outcomes. By examining the overlap of probability density functions of tissue load and strength estimations, or the probability that D > D_c, the probability of an athletic injury occurring can be appropriately quantified. However, to offer practical utility for the prevention of athletic injuries in real-world settings, athletic injury predictions must provide sufficient windows for intervention. For injuries involving sudden unanticipated loads that exceed the possible physiological ranges of tissue strength, this method of athletic injury risk assessment may be of little value, as there is no window of opportunity for intervention. In scenarios where future loads experienced by an athlete can be estimated, tissue damage accumulates over time, or tissue load and strength values converge over time, actualising this approach by obtaining accurate estimations of these variables is likely crucial for achieving high-accuracy athletic injury predictions that offer specific data-driven windows for intervention.

The proportion of studies with results supporting their hypotheses has been implausibly high in sports science, suggesting the widespread presence of questionable research practices (QRPs). Preregistration is recommended to mitigate QRPs.

The aim of this study was to evaluate the uptake of preregistration in sports science journals, and its association with the proportion of supported hypotheses. The influence of journal quartile on these factors was also examined. Differences in hypothesis reporting between published manuscripts and original preregistrations were also explored.

A total of 2006 original research articles published from 19 journals in 2024 were included, of which 201 (10.0%) were preregistered, and 1205 provided a hypothesis (60.0%). Logistic regression analyses assessed whether preregistration frequency and the proportion of supported hypotheses varied across journal quartiles (i.e., quartile 1, 2, 3, and 4, as ranked by SCImago).

The proportion of preregistered studies that had results supporting their hypotheses (45%) were significantly lower than non-preregistered studies (56%) (X² (1) 5. 5978; P = 0.018), although the effect size was negligible (V = 0.07, 95% confidence interval [CI] = 0.01, 0.13). Quartile 3 and 4 journals had less preregistrations (odds ratio [OR] = 0.27, 95% CI = 0.17, 0.41) and supported hypotheses (OR = 0.73, 95% CI = 0.55, 0.97) than quartile 1 journals. Of 134 preregistered papers with a hypothesis, 93 (69.4%) either did not have a hypothesis in their original preregistration or presented a different hypothesis from what was reported in the preregistration.

The uptake of preregistration in sports science is low, and its effectiveness is limited, possibly owing to researchers not adhering to preregistered research plans and adopting QRPs.

This study was prospectively preregistered on the Open Science Framework https://osf.io/c8jfm/files/osfstorage).

Endurance performance is predicted by maximal oxygen uptake, its fractional utilisation at lactate threshold (FU_LT) and exercise economy. These variables are used to estimate speed or power at lactate threshold (LT) and lactate turnpoint (LTP), which serve as performance proxies.

This study examined the relationships between these variables in a large cohort of runners and cyclists and quantified their relative contributions to performance prediction.

495 runners (105 females) and 393 cyclists (42 females) completed incremental exercise tests to determine maximal oxygen uptake (running [R]: 56 mL/kg/min, 3.94 L/min; cycling [C]: 52 mL/kg/min, 3.99 L/min), economy (R: 220 mL/kg/km; C: 14.7 mL/min/W), FU_LT (R: 78%; C: 70%), FU_LTP (R: 88%; C: 84%), and speed or power at LT (R: 12.0 km/h; C: 190 W) and LTP (R: 13.9 km/h; C: 240 W). Single and multiple linear regression models were used to examine the relationship and relative contribution of physiological determinants to performance proxies.

Speed or power at LT and LTP correlated strongly and positively with maximal oxygen uptake (R² = 0.65–0.77; P < 0.001), and inversely with economy (R² = 0.24–0.26; P < 0.001). In contrast, trivial relationships were observed with FU_LT (R² ≤ 0.04; P = 0.01–0.05) or FU_LTP (R² ≤ 0.01; P = 0.01–0.09). Regression models estimating LT and LTP from physiological determinants showed very strong agreement with measured performance proxies (R² = 0.94–0.99; P < 0.001), indicating consistency in their relative contribution to performance proxies. Maximal oxygen uptake contributed most to performance proxies (65–76%) followed by running economy (20–24%), with marginal contributions from FU_LT or FU_LTP (4–11%).

These results indicate that maximal oxygen uptake and economy collectively predict ~ 95% of speed or power at LT and LTP, and by extension performance, whilst the contribution of FU_LT or FU_LTP is limited in populations with heterogeneous characteristics.

Athletic injury remains inadequately conceptualised and poorly defined. Existing definitions lack the conceptual clarity and logical coherence required to support its maturation into a scientifically meaningful and reliably investigable concept. Related constructs that are often integrated into various operational definitions, such as pain and athlete availability, are frequently conflated as fundamental criteria, producing conceptual instability through semantic vagueness, category conflation, and logical contradiction. These deficiencies in conceptual understanding have hindered the development of precise theoretical and operational frameworks capable of supporting formalisation and have, more broadly, undermined the critical scientific principles of predictability, testability, falsifiability, and reproducibility. To address this, this article employs a systematic process of metaphysical analysis and Carnapian explication, grounded in Aristotelian essentialism and classical logic, to develop a new, scientifically robust theoretical definition of athletic injury. This approach utilises well-established logico-philosophical tools such as thought experiments, boundary tests, and deductive reasoning to evaluate the conceptual coherence of existing definitions, and to establish a set of necessary and sufficient conditions for an athletic injury to exist. Through this process, commonly conflated concepts (Symbebekós, ‘accidental properties’) are examined for logical independence and disentangled from essential properties (To ti ēn einai, ‘what it is to be’), revealing the logical structure that anchors this construct in observation and enables its expression within a coherent, logico-mathematical predictive framework. The outcome is an integrative framework that aligns the theoretical, observational, and mathematical dimensions of athletic injury and associated constructs, such as injury severity, recovery, and rate of recovery, into a unified, formalised system of mathematically defined and interrelated entities for consistent application in mathematical modelling, including prediction, simulation, and causal inference. This paves the way for advancements in the assessment and modelling of athletic injury and related phenomena.

Given the widespread use of caffeine among athletes, this meta-analysis quantifies the incidence of acute side effects associated with caffeine supplementation. Despite its well-established performance benefits, evidence on caffeine’s side effects remains fragmented, as these outcomes are often reported only as secondary findings.

To address this gap, we systematically reviewed and meta-analyzed evidence from randomized controlled trials on acute caffeine-related side effects in athletes.

Following PRISMA guidelines, we searched five databases (MEDLINE, Scopus, Web of Science, Embase, Google Scholar) up to July 2025. Eligible studies were randomized controlled trials in athletes aged ≥ 15 years examining acute caffeine ingestion versus placebo with reported side effects. Risk of bias was assessed using PEDro and Cochrane criteria. Data on frequency and magnitude of side effects were pooled using random-effects meta-analyses, with subgroup and dose–response analyses.

A total of 48 studies (940 athletes; 63% male, 37% female) were included in the systematic review, of which 38 were eligible for meta-analysis. The mean caffeine dose was 4.9 ± 2.4 mg/kg (range 1.3–12 mg/kg), commonly ingested as capsules or beverages. Compared with placebo, athletes who ingested caffeine self-reported significantly higher odds of headache (Log OR = 0.74, p < 0.001), abdominal discomfort (Log OR = 1.12, p < 0.001), increased feelings of vigor/activeness (classified in this review as a side effect for methodological consistency, although it may also reflect an ergogenic benefit; Log OR = 1.14, p < 0.001), tachycardia (Log OR = 1.47, p < 0.001; > fourfold higher odds compared with placebo), insomnia (Log OR = 1.20, p < 0.001), increased urine output (Log OR = 1.04, p < 0.001), anxiety (Log OR = 1.29, p < 0.001), and nervousness (Log OR = 0.82, p < 0.001). Meta-regression of dose–response effects showed a significant association between caffeine dose and tachycardia (slope = 0.31, p < 0.001), headache (slope = 0.23, p < 0.001), abdominal discomfort (slope = 0.29, p < 0.001), vigor/activeness (slope = 0.18, p < 0.001), increased urine output (slope = 0.28, p < 0.001), and anxiety (slope = 0.37, p < 0.001).

Caffeine intake in athletes increases the likelihood of side effects in a dose-dependent manner, with tachycardia, insomnia, abdominal discomfort, and anxiety being the most consistent. Evidence suggests that, compared with high doses (> 6 mg/kg), low to moderate doses (≤ 6 mg/kg) of caffeine may reduce the risk of side effects.

Research on fluid-electrolyte balance in athletes has largely emphasized acute hydration strategies to preserve performance, particularly under conditions of prolonged exercise and heat stress. While this focus has yielded valuable practical guidance, it has overshadowed the potential long-term health implications of habitual low water intake (LWI). Emerging evidence from non-athletic populations indicates that chronic LWI, often characterized by persistently elevated arginine vasopressin (AVP) and concentrated urine, may increase renal, endocrine, and metabolic strain, showing associations with insulin resistance, low-grade inflammation, and chronic disease risk. Notably, evidence suggests that up to 40% of the non-athletic population fail to meet the fluid intake recommendations. Furthermore, a considerable proportion of athletes are habitually classified as low drinkers (i.e., ~ 58% consuming < 35 mL·kg⁻¹·day⁻¹), despite being exposed to recurrent and substantial fluid and electrolyte losses during training and competition. Although total body water may remain within normal ranges in these individuals, markers of renal concentrating stress suggest sustained activation of fluid-regulatory systems. Whether this physiological state poses long-term health risks for athletes remains unknown. This short communication argues that habitual LWI represents an underappreciated and potentially modifiable health risk in athletic populations. We highlight critical gaps in longitudinal and mechanistic research, calling for a paradigm shift in sports nutrition that recognizes total daily water intake as both a performance variable and a determinant of long-term health.

In the last decade, Sport for Development (SFD) and Sport for Development and Peace (SDP) reviews have seen an increase in published review research to explore the potential of sport as a vehicle for development to attain Sustainable Development Goals among others. Some reviews have been conducted on several related themes, but to date, no attempt has been made to evaluate and scrutinize review contributions in this field.

The aim of this study is to conduct a systematic review of SFD/SDP reviews to provide a complete and updated picture of the field of research.

A scoping systematic review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines was used to identify reviews published on SFD/SDP since 2000. After applying strict inclusion criteria in eight languages, including gray literature, 21 reviews were identified through database searches in Scopus, SPORTDiscus, ScieLO, SocINDEX, ProQuest, PsycINFO, and Google Scholar. Experts from the field were consulted, mapping of authors and overlapping of studies were conducted and the quality of reviews was assessed.

Findings highlighted diverse thematic focuses, including those aligned with Sustainable Development Goals such as health promotion, gender equality, and educational outcomes, alongside novel areas such as managerial implications and critical pedagogy. Despite the wealth of research, consensus on sport’s developmental potential remains elusive, hindered by methodological limitations and a dearth of quality assessments. Moreover, the dominance of English publications underscores a need for linguistic inclusivity, while re-evaluating terminology and expanding disciplinary engagement can enrich and globalize the discourse. Critical reflection is warranted on the historical context of SFD/SDP, moving beyond colonial narratives to embrace diverse development paradigms, including intra-European perspectives.

The field of SFD/SDP seems to need initiatives that focus on bottom-up approaches, with long-term monitoring, evaluation of changes over time, attention to cultural contexts, and local participation. It also necessitates a rigorous revision of methodologies to better elucidate the multi-level impact of sport-based initiatives on achieving developmental objectives, and to bring in the viewpoints of other disciplines to gain a more complex understanding of the SFD/SDP field.