Sports & Performance Nutrition

Citation model. Claims grounded in AllNutrition's trust-scored library carry an inline bracketed reference [n] linking to the References section, which lists each source's evidence level and AllNutrition trust score (0–1). Where an AllNutrition query returned an overall evidence_strength and consensus_level, those labels are surfaced in the Evidence Review. Only sources actually returned by the tool are cited; no trust scores are invented.

---

1. Introduction

Sports nutrition sits at an unusual intersection in medicine: it is one of the few nutrition domains with a genuine tradition of controlled, mechanistically grounded human experimentation, because performance outcomes are measurable in minutes and seconds rather than decades of disease incidence. That rigor has produced some of the best-supported nutrition interventions in existence — carbohydrate fueling, creatine, caffeine — sitting alongside a supplement marketplace saturated with confident claims resting on little more than a plausible-sounding mechanism. Physicians increasingly encounter athletic and recreationally active patients asking about protein targets, "fat-burning" diets, and pre-workout stacks, and student-athletes and masters athletes alike are vulnerable to both under-fueling (with serious endocrine and skeletal consequences) and predatory supplement marketing.

This module builds the physiological foundation — how the body partitions energy across the phosphagen, glycolytic, and oxidative systems, and how substrate use shifts with intensity — and then applies it to the two nutrients that matter most for performance and body composition (carbohydrate and protein), the handful of ergogenic aids with genuinely strong evidence, and the clinical syndrome that clinicians must not miss: Relative Energy Deficiency in Sport (RED-S). The goal is to equip the physician to distinguish an evidence-backed ergogenic aid from a marketing claim, and to recognize when apparently healthy exercise behavior is masking energy deficiency with systemic consequences.

2. Learning Objectives

By the end of this module, the learner will be able to:

1. Explain the phosphagen, glycolytic, and oxidative energy systems and the crossover concept governing substrate utilization across exercise intensities.
2. Apply evidence-based carbohydrate strategies — loading, intra-exercise intake, and "train-low" periodization — to endurance performance goals.
3. Recommend an evidence-based protein dose, per-meal distribution, and timing strategy for hypertrophy and recovery, and critically reappraise the "anabolic window."
4. Distinguish ergogenic aids with strong evidence (creatine, caffeine, nitrate, beta-alanine, sodium bicarbonate) from weakly supported or unproven supplements.
5. Recognize the clinical presentation, screening, and physiological consequences of RED-S / low energy availability, including bone and endocrine effects.
6. Counsel athletes on hydration/electrolyte strategy, iron screening, recovery nutrition, and safe body-composition/weight-making practices.

3. Scientific Foundations

3.1 Bioenergetics and the crossover concept

Skeletal muscle regenerates ATP through three integrated systems. The phosphagen (phosphocreatine) system provides immediate ATP for the first seconds of maximal effort — sprints, jumps, late-race breakaways — and is the system creatine loading directly augments [23]. The glycolytic system breaks down glucose and glycogen, dominating efforts lasting roughly 1–10 minutes and accounting for 95–98% of cellular glucose utilization at high intensities; its end product, H⁺ accumulation, is the physiological target of buffering agents such as beta-alanine and sodium bicarbonate [4][9]. The oxidative system — mitochondrial β-oxidation and oxidative phosphorylation — dominates rest and low-to-moderate intensity exercise and has a nearly unlimited capacity, at the cost of slower ATP delivery [2].

The crossover concept describes how the relative contribution of fat versus carbohydrate shifts with intensity. At roughly 25% VO2max, about 90% of energy derives from circulating fatty acids; at the crossover point (~65% VO2max), fat and carbohydrate contribute roughly equally; above ~85% VO2max, carbohydrate supplies 70% or more of energy, with muscle glycogen dominant [2][17]. Training status shifts this crossover point rightward — endurance-trained athletes oxidize more fat at a given workload, sparing glycogen — while exogenous carbohydrate intake during exercise can itself prevent or delay the shift toward carbohydrate dominance: in trained cyclists, ingesting 120 g/h of carbohydrate during exercise at 95% of lactate threshold prevented the crossover shift entirely, whereas lower doses only delayed it [1][17].

3.2 Carbohydrate for endurance: loading, during-exercise intake, and train-low periodization

Muscle and liver glycogen are finite, and their depletion is a proximate cause of endurance fatigue. Dose-response data show that 10 g/kg/day of carbohydrate for 48 hours before competition produces significantly higher muscle glycogen than 6 or 8 g/kg/day, without excess GI distress or body-mass gain [5]. During exercise lasting beyond 2–3 hours, 90–120 g/h using multiple transportable carbohydrates (glucose-fructose combinations, which bypass single-transporter saturation above ~60 g/h) is the current guideline-supported range, though benefits plateau or diminish above ~78 g/h in recreationally trained athletes [1][17]. Notably, the ergogenic benefit of carbohydrate supplementation is far less consistent in hot environments (>23°C), where some trials show 3–19% improvements and others show none — heat-driven glycogenolysis may proceed regardless of exogenous intake — so heat-exercising athletes may derive more benefit from hydration and gut-training focus than from maximizing carbohydrate dose alone [6].

"Train-low, compete-high" and "sleep-low" periodization intentionally restrict carbohydrate availability around selected training sessions to amplify molecular signaling (e.g., AMPK, PGC-1α) toward fat-oxidative adaptation, while ensuring high carbohydrate availability for competition. The evidence is genuinely mixed: low-carbohydrate training sessions increase maximal fat oxidation (~200% increase in some protocols) but reduce training speed and increase perceived exertion, and in elite race-walkers, four weeks of periodic carbohydrate restriction showed no superior effect on performance or muscle adaptation compared to consistently high-carbohydrate training [7][3][8]. The practical takeaway — "fueling for the work required," matching carbohydrate intake to the specific demand of each session rather than a uniformly high- or low-carbohydrate diet — is now the more defensible default than either extreme [3][7].

3.3 Protein for hypertrophy and recovery: dose, distribution, leucine, and the "anabolic window"

For resistance-trained individuals, muscle protein synthesis (MPS) and strength gains are maximized in the range of 1.6–2.2 g/kg/day, with intake above 1.6 g/kg/day required to maximize strength gains specifically and ISSN-aligned reviews describing 1.4–2.0 g/kg/day as the minimum anabolic threshold [12][20]. Endurance athletes benefit from slightly less (~1.85 g/kg/day) for recovery and glycogen-sparing purposes [12].

Per-meal distribution matters independently of total intake. While 20 g per meal was once thought to be the ceiling for stimulating MPS, current evidence supports 30–60 g per meal as effectively utilized, with a leucine threshold of roughly 2–3 g per meal in younger adults and 3–4 g in older adults (who exhibit anabolic resistance) required to trigger the mTORC1 signaling cascade [13][15]. Whey protein's rapid digestion kinetics and high leucine content make it the reference standard; soy is the most evidence-supported plant-based alternative, and blending sources or fortifying with leucine narrows the gap with animal protein [16][18].

The "anabolic window" — the belief that protein must be consumed within ~30 minutes post-exercise or gains are lost — is a reappraised concept. Resistance exercise sensitizes muscle to amino acids for a substantially longer period, up to 24 hours, and for younger, healthy adults total daily protein intake is a more important predictor of adaptation than acute peri-workout timing [16]. A crossover study did find evenly distributed intake (30 g × 3 meals) produced higher 24-hour MPS than a heavily skewed distribution (11/16/63 g) [15], and pre-sleep casein (40 g) increases overnight myofibrillar synthesis by roughly 33% versus lower or no pre-sleep protein [20] — so timing and distribution retain value, but the rigid "window" framing is not well supported as a hard constraint.

4. Clinical Relevance

Physicians see this material in three recurring contexts: (1) recreational and competitive athletes asking about legal, evidence-based performance supplements versus expensive or risky proprietary blends; (2) aging and clinical populations (older adults, those in energy restriction, post-surgical patients) for whom the same protein-dose and resistance-training principles apply to prevent sarcopenia; and (3) at-risk athletes — particularly endurance runners, aesthetic-sport athletes, and weight-class competitors — in whom energy restriction, whether intentional or inadvertent, produces RED-S, a condition with under-recognized bone, cardiovascular, endocrine, and psychiatric consequences that primary care and sports medicine physicians are positioned to screen for and that a naive "eat less, train more" framework can dangerously worsen.

5. Evidence Review

Established (high confidence):

• Endurance performance is dose-dependently improved by carbohydrate loading (10 g/kg/day × 48h) and intra-exercise carbohydrate intake (90–120 g/h with multiple transportable carbohydrates). evidence_strength: strong, consensus_level: moderate [1][5][17].
• Creatine monohydrate (loading ~20 g/day × 5–7 days, then 3–5 g/day maintenance) increases strength, power, and lean mass, and is supported by an extensive safety record including adolescent and postmenopausal populations. evidence_strength: strong, consensus_level: moderate [3][22][23][24].
• Caffeine (3–6 mg/kg, up to 9 mg/kg in some protocols) reliably improves endurance and high-intensity performance via adenosine antagonism and reduced perceived exertion. evidence_strength: strong, consensus_level: mixed (mixed chiefly on magnitude and individual variability) [4][28][30].
• Total daily protein intake (1.6–2.2 g/kg/day) is the dominant driver of hypertrophy; the rigid "30-minute anabolic window" is not well supported. evidence_strength: strong, consensus_level: moderate [12][15][16].

Probable:

• Dietary nitrate/beetroot juice (300–600 mg nitrate, 2–3h pre-exercise) improves efficiency and time-to-exhaustion in efforts of 2–30 minutes, with a ceiling effect in highly trained athletes and no benefit for short sprints. evidence_strength: strong, consensus_level: mixed [1][34][35].
• Sodium bicarbonate (0.3 g/kg) and beta-alanine (3–6 g/day, chronic loading) buffer H⁺ accumulation and benefit 1–10 minute high-intensity efforts, though GI distress and low certainty of evidence (particularly in women) temper confidence. evidence_strength: strong (bicarbonate)/moderate (beta-alanine), consensus_level: moderate [37][38][40].
• Protein and resistance training combined counter sarcopenia and anabolic resistance in older adults more effectively than either alone. evidence_strength: strong, consensus_level: moderate [13][14].

Emerging:

• "Train-low/sleep-low" carbohydrate periodization for metabolic adaptation, with unclear translation to elite-level performance gains. evidence_strength: strong (for adaptation), consensus_level: moderate [7][8].
• Individualized sweat-sodium testing (single 20-minute sample) to guide personalized electrolyte replacement rather than uniform fluid targets. evidence_strength: strong, consensus_level: mixed [45][46].

Controversial:

• Ketogenic/low-carbohydrate-high-fat diets for endurance performance: consistently increase fat oxidation and may aid body composition, but the majority of evidence — including elite race-walker RCTs — shows impaired high-intensity training capacity and performance versus high-carbohydrate fueling. evidence_strength: strong, consensus_level: mixed [3][8][9][10].
• BCAAs, glutamine, HMB, and citrulline malate: mechanistically plausible but inconsistent trial evidence, with benefits often disappearing once total energy/protein intake is matched between groups. evidence_strength: moderate, consensus_level: mixed [55][56][57].

Unsupported / overstated:

• The strict "anabolic window" (protein must be consumed within ~30 minutes post-exercise or gains are forfeited) as a rigid rule, given evidence of a much longer (up to 24-hour) window of enhanced muscle sensitivity [16].
• Oral contraceptive pills as a treatment for low-bone-density athletes with RED-S; they do not address the underlying energy deficiency and do not reliably restore bone mineral density [61].

6. Practical Clinical Applications

By goal — endurance performance: Carbohydrate-load (10 g/kg/day) for 48h pre-event; consume 1–4 g/kg in the 1–4h pre-exercise meal; target 90–120 g/h during exercise >2–3h using glucose-fructose blends, with "gut training" during preparation [1][5][17]. Consider caffeine 3–6 mg/kg ~60 minutes pre-event [4]. Nitrate-rich beetroot juice (300–600 mg nitrate, 2–3h pre-event) may help sub-elite athletes in efforts of 2–30 minutes; expect little benefit if already elite-trained or for short sprints [1][35].

By goal — hypertrophy/strength: Target 1.6–2.2 g/kg/day protein distributed across 3–4 meals of 30–40 g each with a leucine-rich source; do not over-prioritize a narrow post-workout window over total daily intake and consistency [12][13][15]. Add creatine monohydrate (loading 20 g/day × 5–7 days or steady 3–5 g/day) for most resistance-training goals; effects on continuous aerobic endurance are minimal, but high-intensity bursts within endurance events can benefit [1][23].

By goal — repeated high-intensity/anaerobic sport (combat sports, team sports, sprinting): Beta-alanine 3–6 g/day chronic loading and/or sodium bicarbonate 0.3 g/kg acutely (2–3h pre-event, individually piloted for GI tolerance) for efforts of 1–10 minutes [9][37][40].

When not to use ergogenics: Avoid recommending BCAAs, glutamine, or HMB as primary strategies when total protein and energy intake are already adequate — evidence suggests much of their apparent benefit reflects unmatched calorie intake rather than a specific effect [12][55]. Avoid ketogenic/very-low-carbohydrate approaches for athletes whose sport demands repeated high-intensity efforts, rapid accelerations, or frequent competition, given consistent evidence of impaired training capacity [3][8][10].

Screening for RED-S/low energy availability: Screen amenorrheic/oligomenorrheic female athletes, athletes with unexplained performance decline or recurrent bone stress injury, and any athlete with a pattern of intentional or unintentional caloric restriction. Prioritize energy availability restoration (adequate intake relative to training load) over pharmacologic bone-protective strategies alone; oral contraceptives are not a substitute for energy repletion [43][60][61][62].

Iron: Screen ferritin routinely (target ≥30 µg/L; consider supplementation with confirmed deficiency <30 µg/L or anemia Hb <120 g/L in females), particularly in female endurance athletes, given a 5–7-fold higher prevalence than in males; dose 60–120 mg elemental iron, morning, away from meals/coffee, with vitamin C to enhance absorption [2][42][43].

Hydration: Individualize rather than apply uniform fluid targets; over-drinking (not under-replacing sodium per se) is the dominant driver of exercise-associated hyponatremia, so pairing personalized sweat-sodium testing with thirst-guided intake is preferable to fixed volume prescriptions, especially in ultra-endurance events [45][46][47].

7. Clinical Pearls

• The crossover point shifts rightward with training — a well-trained endurance athlete burns proportionally more fat at a given absolute workload than an untrained person, sparing glycogen for late-race efforts [2][17].
• "More carbohydrate during exercise" has a ceiling: above roughly 120 g/h (using multi-transportable sugars) and above ~78 g/h in recreational athletes, additional intake yields diminishing performance return and more GI risk [1][17].
• Total daily protein and consistent per-meal thresholds (30–40 g) beat obsessing over the post-workout "window" [15][16].
• The four ergogenic aids with the most consistent, replicated evidence are creatine, caffeine, nitrate/beetroot (context-dependent), and beta-alanine/bicarbonate for buffering — nearly everything else in the sports-supplement aisle has weaker or inconsistent support [1][3][4][9][55].
• Exercise-associated hyponatremia is usually caused by drinking too much, not too little sodium — don't reflexively push electrolyte tablets without assessing fluid balance [45][47].
• A regularly menstruating, well-fueled athlete with a stress fracture still needs an energy-availability work-up; RED-S is not exclusively a "thin female athlete" diagnosis and occurs in males too [43][60].

8. Common Misconceptions

• "You must eat protein within 30 minutes of training or you waste the workout." The anabolic window is measured in hours, not minutes; total daily intake and consistent distribution matter more [16].
• "Low-carb/keto is the best diet for endurance athletes because it 'unlocks' fat-burning." Fat oxidation does increase substantially, but the majority of controlled evidence, including elite-level RCTs, shows impaired high-intensity capacity relative to carbohydrate-supported fueling [3][8][9].
• "Natural" or "proprietary blend" pre-workout and recovery supplements (BCAAs, glutamine, most "fat burners") are next-tier ergogenics comparable to creatine or caffeine. Evidence for most of these is inconsistent or driven by confounded total energy/protein intake, unlike the well-replicated big four (creatine, caffeine, nitrate in context, beta-alanine/bicarbonate) [55][56][57].
• "RED-S only affects extremely lean, visibly underweight athletes." Energy deficiency can occur at normal or even elevated body weight/composition and is frequently missed because visible thinness is absent [60].
• "Oral contraceptives are the standard fix for an athlete with amenorrhea and low bone density." They do not treat the underlying energy deficiency and do not reliably restore bone mineral density; energy availability restoration is primary [61].

9. Summary

Sports and performance nutrition rests on a genuinely strong evidence base for a limited set of interventions: matching carbohydrate availability (loading, intra-exercise dose, and periodized "train-low" approaches) to the metabolic demand of training and competition; hitting a total daily protein target of roughly 1.6–2.2 g/kg/day distributed across leucine-rich 30–40 g meals rather than fixating on peri-workout timing; and selectively using the handful of ergogenic aids — creatine, caffeine, nitrate/beetroot, beta-alanine, and sodium bicarbonate — with consistent, replicated performance benefit and favorable safety profiles. Equally important is what the evidence does not support: ketogenic diets for high-intensity performance, a rigid anabolic window, and most boutique supplements once total energy and protein intake are accounted for. Clinically, the physician's most important contribution is recognizing energy deficiency — RED-S and low energy availability — which can present with bone stress injury, menstrual dysfunction, or unexplained performance decline in athletes who may not appear underweight, and steering management toward energy repletion rather than symptomatic pharmacologic fixes alone.

10. References

Ordered by evidence strength / relevance. Evidence level and AllNutrition trust score (0–1) as returned by the tool.

1. International Society of Sports Nutrition position stand: effects of dietary antioxidants on exercise and sports performance. JISSN (2026). Guideline — trust 0.907.
2. The Effect of Diet and Dietary Supplements on Iron Status of Active Females: A Systematic Review and Meta-analysis of Interventional Trials. Sports Medicine (2026). Systematic review — trust 0.912.
3. Creatine monohydrate for lean mass, strength, and bone density in postmenopausal women: a systematic review and meta-analysis. JISSN (2026). Systematic review — trust 0.857.
4. Effects of Combined Versus Isolated Beta-Alanine and Sodium Bicarbonate Supplementation on Physical Capacity in Highly Trained Female Basketball Players: A Randomized Controlled Trial. IJSPP (2026). RCT — trust 0.938.
5. Nutrition in CrossFit® – scientific evidence and practical perspectives: a systematic scoping review. JISSN (2025). Systematic review — trust 0.885.
6. Carbohydrate supplementation for endurance exercise in the heat: a systematic review with practical recommendations. JISSN (2026). Systematic review — trust 0.827.
7. The effectiveness of protein supplements on athletic performance and post-exercise recovery — a Bayesian multilevel meta-analysis of randomized controlled trials. JISSN (2026). Systematic review — trust 0.827.
8. Making Weight Makes Sense: Relative Performance Gains After Rapid Weight Loss in Powerlifting: A Randomized Controlled Trial. JISSN (2025). RCT — trust 0.835.
9. Effects of β-alanine supplementation on kickboxing-specific anaerobic performance, neuromuscular power, and strength endurance. PLOS ONE (2026). RCT — trust 0.835.
10. Metabolic Changes and Predictors of Menstrual Recovery Following a Diet Intervention in Exercising Females with Oligo/Amenorrhea: The REFUEL Study. Clinical & Translational Metabolism (2026). RCT — trust 0.835.
11. Muscle and Bone Health in Postmenopausal Women: Role of Protein and Vitamin D Supplementation Combined with Exercise Training. Nutrients (2018). Review — trust 0.838.
12. Seasonal changes in energy intake and emerging indicators of energy availability in young elite Nordic skiers. JISSN (2026). RCT — trust 0.853.
13. Nutrition in the prevention and treatment of skeletal muscle ageing and sarcopenia. Proceedings of the Nutrition Society (2025). Review — trust 0.69.
14. Targeted Supplementation and Nutritional Strategies for Healthy Aging: A Review of Physiological and Molecular Benefits. Current Nutrition Reports (2026). Review — trust 0.833.
15. An Update on Protein, Leucine, Omega-3 Fatty Acids, and Vitamin D in the Prevention and Treatment of Sarcopenia and Functional Decline. Nutrients (2018). Review — trust 0.812.
16. Sustaining Muscle, Cardiovascular Health, and the Environment: Is Plant-Based Protein the Key? Nutrients (2026). Review — trust 0.715.
17. From Metabolism to Medals: Contemporary Perspectives and Revisiting Carbohydrate Guidelines for Fueling Endurance Athletes during Exercise. The Journal of Nutrition (2026). Review — trust 0.70.
18. Are plant-based and omnivorous diets the same for muscle hypertrophy? A narrative review. Nutrition (2025). Review — trust 0.72.
19. Does a low-carbohydrate diet impede endurance sports performance? Yes. AJCN (2026). Review — trust 0.75.
20. A Novel Chronotype-Based Mediterranean Diet Pyramid. Current Nutrition Reports (2026). Review — trust 0.695.
21. Evaluating the Safety of Creatine Monohydrate in Adolescents: A Systematic Review of Renal, Hepatic, and Cardiometabolic Outcomes. Cureus (2026). Systematic review — trust 0.65.
22. The emerging and evolving evidence supporting creatine as an ergogenic aid: history and applications. JISSN (2026). Review — trust 0.778.
23. Role of creatine supplementation in intestinal health: a narrative review. Nutrition (2026). Review — trust 0.625.
24. Caffeine makes a splash: a systematic review and multilevel meta-analysis exploring the effects of caffeine intake on swimming performance. JISSN (2026). Systematic review — trust 0.725.
25. Revisiting the evidence on caffeine mouth rinse: effects on exercise and cognitive performance. JISSN (2026). Review — trust 0.787.
26. The chemistry of the nitrate–nitrite–nitric oxide pathway: regulating muscle oxygenation and exercise performance. RSC Advances (2026). Review — trust 0.73.
27. Acute beetroot juice ingestion fails to improve sprint performance and neuromuscular function in trained male sprinters. JISSN (2026). RCT — trust 0.772.
28. Effects of beta-alanine supplementation on exercise performance and related physiological outcomes in women: a systematic review and meta-analysis. Frontiers in Nutrition (2026). Systematic review — trust 0.688.
29. Effects of carnosine supplementation on physical endurance: a placebo-controlled randomized clinical trial. JISSN (2026). RCT — trust 0.713.
30. Intra-individual reliability of blood bicarbonate responses and gastrointestinal symptoms following sodium citrate supplementation. JISSN (2026). Observational — trust 0.752.
31. Menstrual Cycle and Hormonal Contraceptives in Female Athletes: Should Symptoms and Nutrition Matter More than Cycle Phase? Nutrients (2026). Review — trust 0.715.
32. Optimizing Performance Nutrition for Adolescent Athletes: A Review of Dietary Needs, Risks, and Practical Strategies. Nutrients (2025). Review — trust 0.73.
33. Athlete Hydration: Beyond Performance Toward Long-Term Health. Sports Medicine (2026). Review — trust 0.675.
34. Temporal Stability, Reproducibility and Predictability of Whole-Body Sweat Sodium Concentration During Prolonged Cycling in the Heat. Nutrients (2026). Observational — trust 0.743.
35. Associations Between Hydration, Sodium Intake, and Body Mass in Ultra-Endurance Trail Runners Under Ecological Race Conditions. Physiologia (2026). Observational — trust 0.688.
36. Potential role of L-citrulline in regulating exercise performance and muscle protein metabolism. npj Science of Food (2026). Review — trust 0.75.
37. Enhancing effects of diphenyl diselenide and β-hydroxy β-methylbutyrate combined with exercise on neuroprotection, memory, mitochondrial function, muscle function, and inflammation regulation in older adults. Frontiers in Nutrition (2026). Review — trust 0.637.
38. Effects of acute HMB-FA supplementation on antioxidant status and muscle damage in Elite Judoka: a randomized pilot trial. JISSN (2026). RCT — trust 0.588.
39. CRITICAL IMPLICATIONS OF FEMALE BONE METABOLISM IN ORTHOPEDICS: STATE OF THE ART. Journal of ISAKOS (2026). Review — trust 0.73.
40. CRITICAL IMPLICATIONS OF FEMALE BONE METABOLISM IN ORTHOPEDICS (oral contraceptive/bone density finding). Journal of ISAKOS (2026). Review — trust 0.73.
41. Association between energetic status and estrogen variability in recreationally active women. JISSN (2025). Observational — trust 0.74.

Supporting sources also surfaced: Dose–Response of Dietary Carbohydrate Intake on Skeletal Muscle Glycogen (Scand J Med Sci Sports 2026, RCT, trust 0.65); Consensus Document of the Spanish Nutrition Society (SEÑ) on Nutritional Strategies in Sports (Nutrients 2025, review, trust 0.745); Ketogenic diet benefits body composition and well-being but not performance (JISSN 2017, observational, trust 0.62); Carnivore and Animal-Based Diets in Sport (Nutrients 2026, review, trust 0.685); The ketogenic diet is not for everyone (Annals of Medicine 2026, review, trust 0.698); Caffeine enhances performance regardless of fueling strategy (BJN 2025, RCT, trust 0.817); Dietary interventions interact with the perception of effort (JISSN 2026, review, trust 0.787); A Comprehensive Review of the Physiology and Evidence Base to Guide the Use of Ergogenic and Medical Supplements for Enhanced Cycling Performance (JISSN 2026, review, trust 0.73); Do coaches and athletes share the same weight-loss practices? (Frontiers in Nutrition 2026, observational, trust 0.77); Cutting weight, gaining stress (Frontiers in Psychology 2026, observational, trust 0.752); Post-competition recovery in natural physique athletes (JISSN 2026, observational, trust 0.70); The frequency of weigh-ins, weight intentionality and management (Eating Behaviors 2016, observational, trust 0.665).