Best for Athletic Performance

Creatine monohydrate is one of the most thoroughly studied sports supplements with consistent, large-scale evidence proving efficacy for increasing muscle strength and lean mass when combined with resistance training in humans across multiple age groups.

Ashwagandha supplementation (600 mg/day root extract) consistently improves cardiorespiratory endurance (VO2max) and muscle strength in healthy adults and athletes across multiple RCTs, with demonstrated benefits in recovery and stress biomarkers during training.

Rhodiola rosea demonstrates consistent positive effects on endurance performance, anaerobic power, and recovery markers in humans, supported by multiple well-designed RCTs and recent meta-analyses showing moderate effect sizes across diverse athletic populations.

Iron supplementation is proven effective for improving athletic performance in iron-deficient athletes, particularly for endurance capacity and maximal oxygen consumption. Multiple high-quality RCTs and meta-analyses confirm clinically meaningful improvements in performance measures when iron status is corrected.

Whey protein supplementation combined with resistance training produces consistent, clinically meaningful improvements in muscle mass, strength, and physical performance in humans. Effect sizes are moderate to large, particularly in older adults and those with sarcopenia, with results replicated across multiple independent RCTs and meta-analyses.

Beta-alanine is a well-established ergogenic aid with proven efficacy for improving high-intensity exercise performance lasting 60–240 seconds, supported by multiple meta-analyses and human RCTs. Effects are most consistent for anaerobic power, repeated-sprint ability, and time-to-exhaustion; strength and body composition effects are modest or negligible.

SS-31 (elamipretide) shows probable efficacy for athletic performance and exercise tolerance in humans with mitochondrial myopathy, based on 3 human RCTs with modest effect sizes. Animal studies consistently demonstrate improved exercise endurance and mitochondrial function, but human results are mixed and modest in magnitude.

Follistatin 344 shows probable efficacy for athletic performance through resistance training and supplementation interventions, with consistent increases in follistatin levels and improved follistatin/myostatin ratios across multiple human RCTs. However, evidence is limited by small to moderate sample sizes, short study durations (6-12 weeks), and the fact that follistatin changes are biomarkers rather than direct performance measures in most studies.

Omega-3 supplementation shows probable but inconsistent benefits for athletic performance, with clearer effects on recovery and muscle damage markers than on direct performance outcomes. Evidence is moderate-quality with mixed results across multiple small-to-medium human RCTs.

Magnesium supplementation shows modest benefits for athletic performance and recovery, with the strongest evidence for reducing muscle soreness after eccentric exercise and improving anaerobic power. However, results are inconsistent across studies, and several high-quality RCTs found no benefit or even detrimental effects on aerobic performance.

NAC shows moderate evidence for improving athletic performance through reduced muscle soreness and oxidative stress biomarkers, but efficacy on actual performance metrics is inconsistent and modest. Meta-analyses indicate likely benefits for soreness and lactate reduction, but individual RCTs frequently show null or small effects on power output.

Vitamin D3 supplementation shows modest, inconsistent effects on athletic performance and muscle strength in humans. While some RCTs report improvements in specific measures, meta-analyses and larger trials demonstrate mixed or null results for the primary athletic performance outcomes.

Curcumin shows probable efficacy for reducing exercise-induced muscle damage and soreness in humans, with multiple small RCTs demonstrating improvements in muscle damage markers and perceived pain. However, effects on broader athletic performance measures (strength, power, endurance) remain largely unproven, and findings are inconsistent across studies.

Quercetin shows modest improvements in endurance performance and muscle recovery in some human studies, but effects are small, inconsistent across populations, and often not replicated. Evidence suggests potential benefits for untrained individuals and eccentric exercise recovery, but efficacy in trained athletes is unproven.

Resveratrol shows probable efficacy for athletic performance and muscle recovery in humans, but evidence is mixed and limited to small-to-moderate RCTs with inconsistent results. Some studies demonstrate benefits for mitochondrial function and DOMS reduction, while others show no improvement in performance adaptations.

NMN shows plausible benefits for athletic performance in humans, but evidence remains limited to 2 small RCTs with modest sample sizes. Animal studies consistently support improved endurance and mitochondrial function, but human efficacy is not yet conclusively proven.

CoQ10 supplementation shows probable benefits for reducing exercise-induced muscle damage markers and oxidative stress in athletes, with some evidence for improved anaerobic performance and lower-body strength. However, effects on aerobic performance and maximal oxygen uptake remain inconsistent across studies, and clinical meaningfulness for athletic performance is not definitively proven.

Collagen peptides show probable efficacy for athletic performance, primarily through enhancing tendon and connective tissue adaptations to resistance training. However, effects on muscle hypertrophy and strength are inconsistent, with whey protein generally proving superior for muscle growth in direct comparisons.

Probiotic supplementation shows probable benefits for athletic performance, particularly in reducing exercise-induced muscle damage markers, improving body composition, and enhancing recovery—but evidence remains inconsistent with small-to-moderate sample sizes and mixed results across performance metrics.

Melatonin shows probable but not conclusive benefits for athletic performance, with consistent evidence for reducing exercise-induced muscle damage and oxidative stress, but mixed results on direct performance metrics like aerobic capacity and strength.

Tongkat Ali shows probable efficacy for athletic performance when combined with resistance training, with consistent improvements in muscle strength and power across multiple human RCTs. However, evidence is limited by small sample sizes, short intervention periods, and mixed results on isolated supplementation without concurrent exercise.

Maca shows consistent anti-fatigue and endurance-enhancing effects in animal models and some human studies, but human evidence remains limited with mixed results in sport-specific performance. Efficacy is probable but not conclusively demonstrated in athletes.

Black seed oil (Nigella sativa) shows probable efficacy for athletic performance, specifically anaerobic power and recovery markers, based on one human RCT and supporting observational studies. However, evidence is limited to small human trials and animal models; no large-scale RCT replication exists.

Aged garlic extract shows probable benefits for athletic performance in humans, with evidence of improved aerobic fitness and microvascular function in two human studies. However, efficacy is not conclusively proven due to small sample sizes, limited human trials, and inconsistent mechanistic findings across animal studies.

Green tea extract shows mixed but somewhat promising effects on athletic performance in humans, with modest improvements in aerobic capacity and fat metabolism markers, but inconsistent effects on actual performance outcomes. Evidence is limited to small human RCTs with variable methodologies.

Spirulina shows modest benefits for some aspects of athletic performance, particularly endurance-related markers like heart rate reduction and hemoglobin elevation, but evidence is inconsistent and clinically meaningful performance gains remain unproven. Most studies are small, and many report null effects on primary performance outcomes.

Fenugreek demonstrates probable efficacy for enhancing strength and body composition in resistance-trained individuals, with consistent positive effects on leg press 1RM and fat loss across multiple human RCTs. However, evidence is limited by small to moderate sample sizes and inconsistent findings on other performance markers like glycogen resynthesis.

Glucosamine + Chondroitin shows modest efficacy for reducing osteoarthritis pain and improving physical function, but the evidence is inconsistent and effects are generally small. When combined with exercise, the supplement provides no additional benefit beyond exercise alone.

Vitamin C supplementation shows modest, inconsistent benefits for athletic performance. While some studies report improvements in force development and recovery markers, multiple high-quality RCTs demonstrate that vitamin C does not enhance aerobic capacity, endurance performance, or resistance training adaptations, and may actually blunt training-induced mitochondrial adaptations.

Vitamin B Complex shows probable benefit for athletic performance, primarily by reducing blood lactate during recovery and supporting energy metabolism, but evidence comes from mostly small human RCTs with inconsistent effect sizes and limited independent replication.

Vitamin E supplementation shows modest protective effects against exercise-induced muscle damage and oxidative stress markers in trained athletes, but does not reliably enhance athletic performance metrics. Evidence is mixed and inconsistent across studies.

Selenium supplementation shows probable but not conclusive efficacy for athletic performance, with human RCT evidence demonstrating modest improvements in muscle function and antioxidant status during training, though results are mixed and effect sizes are inconsistent.

Urolithin A shows probable benefits for athletic performance and muscle function in humans, with multiple RCTs demonstrating improvements in muscle strength and endurance. However, efficacy is not conclusively proven due to small sample sizes, inconsistent effects on key performance metrics (e.g., peak power output), and limited independent replication across diverse athletic populations.

Astaxanthin shows probable efficacy for athletic performance, particularly in aerobic exercise and endurance capacity, with consistent improvements in time-to-exhaustion and cycling performance across multiple human RCTs. However, evidence is mixed for other athletic metrics (muscle damage recovery, DOMS, anaerobic power), and sample sizes are generally small with some independent replications showing null results.

Boswellia, primarily in combination formulations with curcumin, demonstrates probable efficacy for exercise-related musculoskeletal pain and oxidative stress in athletes based on 2 human RCTs. However, evidence is limited by small sample sizes, short study durations, and lack of independent replication of results.

Pycnogenol shows probable efficacy for athletic performance based on multiple human studies demonstrating improvements in endurance, strength, and recovery, but evidence is limited by small sample sizes, short durations, and lack of independent replication by different research groups.

Bovine colostrum shows modest benefits for athletic performance, with evidence strongest for lower-body power and gut barrier protection during exercise. However, effects on direct performance measures are inconsistent, and immune function improvements remain mechanistically unclear.

Beta-glucans show probable benefits for athletic performance and exercise-related immune function in humans, with multiple RCTs demonstrating reduced upper respiratory infections and improved immune markers post-exercise. However, evidence is limited by small sample sizes, inconsistent findings on direct performance metrics, and lack of independent replication across research groups.

Cordyceps militaris shows probable efficacy for athletic performance, primarily in improving time to exhaustion and aerobic capacity in young, active individuals. However, evidence is limited to 1 human RCT with modest sample size (n=28) and multiple animal studies; results are inconsistent across different performance metrics.

Reishi shows probable efficacy for athletic performance in humans, with two RCTs demonstrating improvements in aerobic capacity, endurance, and grip strength. However, evidence remains limited by small sample sizes and mixed results from one observational study showing no effect on VO2max.

Epicatechin shows probable efficacy for athletic performance and muscle adaptation, primarily through mechanisms enhancing mitochondrial biogenesis and angiogenesis. Evidence is moderate: multiple human RCTs demonstrate positive effects on endurance capacity and muscle strength, but sample sizes are small (n<30 in most studies), results are inconsistent across performance metrics, and clinical meaningfulness remains uncertain.

Pomegranate extract shows probable benefits for athletic performance, particularly in endurance and cardiovascular function, supported by multiple human RCTs. However, effects are inconsistent across exercise types and study populations, with small sample sizes limiting definitive conclusions.

Grape seed extract shows probable benefits for athletic performance in humans, primarily through improved endothelial function and reduced cardiovascular strain during exercise. However, evidence remains limited to small RCTs (n=12-50) with inconsistent effect sizes, and no large-scale replicated studies confirm clinical meaningfulness.

Three human RCTs demonstrate that ecdysterone supplementation produces modest but statistically significant increases in muscle mass and strength when combined with resistance training, with effect sizes larger than placebo but smaller than traditional anabolic steroids. However, evidence remains limited by small sample sizes and one negative null study.

Cistanche shows probable efficacy for athletic performance and muscle function in humans, supported by 2 RCTs with positive results in strength gains and walking ability. However, evidence is limited by small sample sizes, population specificity (untrained vs. elderly), and lack of independent replication across diverse athletic populations.

Schisandra chinensis shows probable efficacy for athletic performance based on 3 human RCTs and multiple animal studies, with demonstrated effects on muscle strength, fatigue markers, and endurance. However, evidence remains limited by small sample sizes, short intervention periods, and lack of independent replication across studies.

CLA supplementation shows modest benefits for body composition (small reductions in body fat and increases in lean mass) when combined with exercise, but has minimal to no effect on athletic performance metrics like VO2 max, endurance capacity, or strength gains in humans. Evidence is mixed and clinically modest.

Astragalus shows probable efficacy for athletic performance and exercise recovery in humans, with multiple RCTs demonstrating improvements in endurance, muscle function, and fatigue markers. However, sample sizes remain small (n<100) and results have not been independently replicated across all key outcomes.

Butyrate and butyrate-producing bacteria are consistently associated with improved markers of athletic performance and recovery in humans, including enhanced microbial diversity, improved metabolic function, and better exercise capacity. However, evidence remains limited to observational studies and small RCTs; no large-scale, well-powered human RCTs directly demonstrate butyrate supplementation improves sport-specific performance outcomes.

Betaine supplementation shows probable efficacy for improving lower body strength and vertical jump performance in resistance-trained individuals, with modest improvements in some endurance and CrossFit-specific tasks. However, effects are inconsistent across studies, effect sizes are small-to-moderate, and evidence for upper body strength and anaerobic power is lacking.

Alpha-GPC shows probable efficacy for athletic performance based on 5 human RCTs, with consistent improvements in explosive power, endurance, and recovery markers. However, evidence is limited by small sample sizes (n=12-48), short supplementation periods (6 days to 7 days), and modest effect sizes that vary across outcome measures.

Bacopa monnieri shows probable efficacy for cognitive performance (particularly attention) in a single human RCT, but evidence for athletic performance specifically is weak. The compound improved alertness and attention measures in healthy adults but did not improve physical endurance performance.

Phosphatidylserine (PS) shows probable efficacy for athletic performance, particularly in attenuating exercise-induced cortisol elevation and improving endurance capacity in high-intensity cycling. However, evidence is limited to small human RCTs (n<30 per group) with inconsistent findings on oxidative stress markers and muscle damage.

Panax ginseng shows mixed but somewhat promising effects on athletic performance, with the strongest evidence for reducing exercise-induced muscle damage and improving recovery markers. However, efficacy for improving aerobic or anaerobic performance itself remains unproven in humans.

L-Theanine shows probable but not conclusive efficacy for athletic performance, particularly when combined with caffeine. Human RCT evidence is limited to small samples (n=12-22) with mixed results on physical performance and consistent benefits for cognitive function during sport-specific tasks.

L-tyrosine shows probable but not conclusive efficacy for athletic performance, with emerging evidence that it may benefit endurance performance specifically under mental fatigue conditions in humans. However, results are inconsistent across studies and effect sizes are modest.

L-glutamine shows mixed efficacy for athletic performance in humans. While some RCTs demonstrate improvements in muscle strength recovery and soreness following eccentric exercise, other well-designed studies find no benefit for endurance performance, gut permeability during heat stress, or neuromuscular function. Evidence is moderate but inconsistent.

GABA supplementation shows probable benefits for athletic performance, particularly in esports and resistance training contexts, with evidence from 6 human RCTs demonstrating improvements in muscle mass, game performance, and mood. However, efficacy is not conclusive due to small sample sizes, limited replication, and mixed mechanistic findings.

L-Citrulline shows modest, inconsistent benefits for athletic performance with evidence primarily from small-to-moderate human RCTs. While some studies report improvements in repetitions to failure and anaerobic power, many high-quality trials show null or trivial effects, and meta-analyses reveal mixed results depending on exercise type and population.

HMB supplementation shows modest benefits for athletic performance and physical function, particularly in older adults and sarcopenic patients when combined with exercise. However, evidence in young, trained athletes is weak or null, and effect sizes are generally small.

Taurine shows probable but inconsistent ergogenic effects for athletic performance, with strongest evidence for endurance exercise in heat and anaerobic power, but weak or null effects in multiple other contexts. Human RCTs are limited in sample size and somewhat contradictory.

BCAAs show modest, inconsistent benefits for athletic performance and recovery. Some studies demonstrate improvements in muscle soreness and endurance capacity, but effects on strength, power, and functional performance are weak or absent when adequate protein intake is controlled.

L-arginine supplementation shows modest improvements in aerobic performance (VO2 max) and some inflammatory markers in trained athletes, but evidence for direct athletic performance enhancement is inconsistent and limited by small sample sizes and mixed results across studies.

L-tryptophan supplementation shows mixed but potentially meaningful effects on athletic performance in humans, with positive results in some exercise modalities (mixed aerobic-anaerobic work, endurance at submaximal intensity) but null findings in pure running endurance. Evidence quality is moderate: 4 human RCTs exist, but sample sizes are small (n=12-49), results are inconsistent across study designs, and findings have not been independently replicated by multiple research groups.

BPC-157 has shown promise for athletic performance and tissue repair in animal studies, but human evidence is extremely limited with no controlled trials demonstrating proven efficacy.

Epithalon shows plausible but unproven effects on athletic performance, with one animal study demonstrating age-related benefits in exercise capacity in rats. No human trials exist to establish efficacy in athletes.

MOTS-c shows promise for athletic performance in animal studies, with some evidence that acute endurance exercise increases circulating levels in humans and that exogenous MOTS-c improves exercise capacity in mice. However, proven efficacy in humans is limited to observational correlations and small intervention studies without consistent performance improvements.

LL-37 levels change in response to exercise in humans, but there is no evidence that LL-37 supplementation or elevation improves athletic performance. Studies document LL-37 as a salivary antimicrobial peptide that responds to acute exercise, but efficacy for athletic performance goals remains unproven.

GHRP-6 reliably stimulates GH secretion in humans and enhances exercise-induced GH release, but evidence for actual athletic performance improvement is absent. All human studies measure GH biomarkers only; no trials assess strength, power, endurance, or competitive athletic outcomes.

Humanin levels increase acutely in response to exercise in humans, particularly endurance exercise, and show correlations with metabolic improvements in training studies. However, no human RCTs have demonstrated that humanin supplementation directly improves athletic performance, and efficacy remains plausible but unproven.

GDF-11 shows promising effects on muscle function and exercise capacity in animal models and one small human RCT, but efficacy in humans remains unproven. Evidence is limited to a single human RCT (n=30) and mechanistic animal studies; independent human replication is absent.

VIP levels increase during and after exercise in humans, but there is no evidence that VIP supplementation or manipulation enhances athletic performance. Studies document VIP as a biomarker of exercise response, not a performance enhancer.

Vilon (Lys-Glu) increased physical activity and endurance in aging mice, but no human studies exist to demonstrate efficacy for athletic performance. Evidence is limited to a single animal study with no independent replication.

Ibutamoren (MK-677) shows potential to increase lean mass and strength when co-administered with SARMs in a single case report, but efficacy for athletic performance is not proven due to minimal human evidence and lack of controlled trials.

MGF is a locally-produced IGF-1 isoform that increases in response to resistance exercise and correlates with muscle adaptation, but no human studies demonstrate that MGF supplementation actually improves athletic performance or muscle growth beyond the natural exercise response.

GLP-1 receptor agonists have not been directly studied for athletic performance enhancement in healthy athletes. Available evidence shows improvements in exercise capacity and walking distance in patients with cardiovascular disease or obesity-related conditions, but no evidence supports performance benefits in athletic populations.

Three human RCTs suggest Cortexin may enhance cognitive and functional performance when combined with other interventions (breathing exercises, microcurrent therapy) or in specific populations (cerebral palsy children). However, no study isolates Cortexin's effect on athletic performance, and efficacy remains plausible but unproven for the stated goal.

Zinc supplementation shows plausible benefits for athletic performance through hormonal and antioxidant mechanisms, but evidence is limited to small human studies and animal models with inconsistent or modest effect sizes. No large, well-controlled human RCTs demonstrate clinically meaningful improvements in athletic performance metrics.

Berberine shows metabolic benefits in prediabetic/diabetic humans (improved fasting glucose and insulin resistance) and protective effects on muscle function in obese mice, but there is no direct evidence that berberine enhances athletic performance in healthy athletes. Efficacy for the stated goal of 'athletic performance' is not demonstrated.

Alpha-lipoic acid shows promise for enhancing antioxidant status and oxidative stress markers during exercise in animal models and small human studies, but does not consistently improve actual athletic performance or exercise capacity in human trials.

One double-blind RCT in humans found that vitamin K2 supplementation (240 μg/d MK-7 for 12 weeks) produced no main effect on muscle recovery or performance in young adults, with only selective benefits observed in older adults that lack a clear clinical pattern.

Boron supplementation does not improve athletic performance, testosterone, or muscle growth in humans despite theoretical mechanisms. One rigorous RCT found no effect on testosterone or lean mass; mechanistic studies in animals and early human trials suggest hormone modulation but lack clinical translation to performance gains.

Milk thistle shows plausible benefits for athletic performance and exercise recovery in animal models, but no human clinical trials exist to prove efficacy. Current evidence is limited to mechanistic studies in rodents with liver disease or stress conditions.

Saw palmetto has been studied in combination with other compounds for athletic performance and hormone markers, but there is no direct evidence that saw palmetto alone improves athletic performance. Most human studies were underpowered (n<30) and focused on hormone changes rather than actual performance outcomes.

Vitamin B12 shows plausible but unproven effects on athletic performance. One human RCT demonstrated improved cycle ergometer endurance in COPD patients with B12 supplementation, but this is a clinical population with high baseline deficiency, not healthy athletes. Pre-workout formulas containing B12 as one ingredient showed no isolated B12 effects.

Chromium supplementation does not demonstrably improve athletic performance, strength, or body composition in humans despite extensive study. Most rigorous RCTs show null or minimal effects independent of exercise training.

One human RCT shows fisetin combined with interval training may support weight loss and adipokine improvements in obese men, but evidence for athletic performance specifically is absent. The compound is discussed theoretically as a senolytic agent with anti-inflammatory potential, but no direct athletic performance outcomes have been demonstrated.

Spermidine shows plausible benefits for athletic performance and muscle health through enhanced autophagy and mitochondrial function, but efficacy in humans remains unproven. Current evidence relies heavily on animal models and one small pilot study; a large human RCT is ongoing but results are not yet available.

Sulforaphane shows promise for athletic performance in animal models through Nrf2-pathway activation and antioxidant defense, but human evidence is limited and inconsistent. The only metabolically demanding RCT (n=17) found no effect on exercise performance, lactate recovery, or muscle power despite confirmed sulforaphane bioavailability.

Glutathione supplementation shows mechanistic promise for athletic performance through antioxidant and nitric oxide pathways, but human efficacy is unproven. Only two small human RCTs exist, with mixed and limited performance outcomes.

TUDCA shows mechanistic promise for athletic performance through mitochondrial protection and stress reduction in animal models, but no human clinical trials demonstrate efficacy for athletic performance. Current evidence is limited to animal studies and cell culture work.

Shilajit's effects on athletic performance are not directly demonstrated in these abstracts. One human RCT studied it as part of a multi-ingredient supplement during exercise intervention for metabolic syndrome (results incomplete), and one animal study showed it may reduce fatigue-related behaviors in rats—but neither provides direct evidence of athletic performance enhancement.

Chaga (Inonotus obliquus) shows promising effects on exercise performance and fatigue in animal models, including improved endurance and glycogen storage. However, human evidence is limited to a single RCT where chaga was part of a multi-ingredient supplement, making it impossible to isolate chaga's independent contribution to athletic performance.

Pterostilbene shows promise for athletic performance in animal models through enhanced mitochondrial function and muscle adaptations, but evidence is limited to one small human RCT with modest effects on muscle cross-sectional area. Human efficacy for athletic performance remains largely unproven.

Olive leaf extract shows plausible benefits for athletic performance and endurance in animal models through mitochondrial activation, but efficacy is unproven in humans. Only 1 human RCT exists, and it found no effect on whole-body metabolism or fatigue resistance despite mechanistic changes.

MSM shows biologically plausible anti-inflammatory and antioxidant effects in small human studies and animal models, but evidence for actual athletic performance improvement is lacking. No studies demonstrate meaningful gains in athletic metrics like strength, speed, endurance, or power output.

Bromelain has theoretical anti-inflammatory properties supported by in-vitro research and meta-analyses of clinical trials showing reduced inflammatory markers. However, the only human RCT directly testing bromelain for athletic performance (DOMS) found no significant effect compared to placebo or ibuprofen.

Stinging nettle combined with exercise training shows consistent improvements in metabolic and cognitive parameters in diabetic animal models, but no human studies exist to demonstrate efficacy for athletic performance. All evidence is limited to rodent studies with diabetes induction.

Mucuna pruriens (15 mg L-Dopa standardized extract) was studied as part of multi-ingredient pre-workout supplements in two human RCTs, but the abstracts do not report efficacy findings specific to Mucuna pruriens alone, making isolated efficacy unproven for athletic performance.

Tribulus terrestris shows plausible but unproven efficacy for athletic performance in humans. Multiple small RCTs report mixed results with no consistent improvement in strength, body composition, or power output, though some studies suggest modest benefits to oxidative stress markers and anaerobic power.

Echinacea supplementation does not demonstrate proven efficacy for improving athletic performance in humans. While one small RCT showed improvements in EPO and running economy, multiple subsequent meta-analyses and reviews found no consistent benefit on aerobic capacity, VO2max, or blood oxygen markers in athletes.

Methylene blue shows neuroprotective effects against exhaustive exercise-induced neurological damage in rats, but no human trials exist. Efficacy for athletic performance in humans remains unproven.

Rapamycin blocks the acute muscle protein synthesis response to resistance exercise in humans and impairs exercise-induced muscular adaptations in some contexts, making it unsuitable for athletic performance enhancement. Limited human data suggest potential benefits for recovery from overtraining or age-related muscle decline, but efficacy for athletic performance is not established.

D-ribose shows plausible but unproven efficacy for athletic performance. While one RCT demonstrated maintained work output during repeated sprints, three other human RCTs found no significant effects on anaerobic capacity, performance, or recovery markers.

Lion's Mane shows plausible effects on muscle endurance in animal models via PPARδ activation, but human efficacy for athletic performance remains unproven. A single human trial found no effects on metabolic flexibility or cognition during exercise.

Ginkgo biloba has been studied for athletic performance in a small number of human RCTs with mixed results. Two studies show modest improvements in aerobic performance metrics (VO₂max), but evidence is limited by small sample sizes, short intervention periods, and lack of independent replication.

PQQ supplementation shows promise for enhancing mitochondrial biogenesis markers (PGC-1α) in humans during endurance training, but does not demonstrably improve actual aerobic performance metrics. Evidence is limited to one small human RCT with mixed results.

Piracetam shows plausible effects on physical performance and endurance in animal models and limited human studies, but efficacy for athletic performance in humans is not yet proven. Human evidence is sparse and confined to small, non-rigorous trials with mixed designs.

Phenylpiracetam (carphedon) shows promise for athletic performance based on one animal study demonstrating increased locomotor activity, but no human efficacy trials exist. Clinical use is reported but not scientifically validated in humans for this goal.

One rat study suggests uridine nucleotides (CMP/UMP) may improve exercise endurance and alter glucose metabolism, but no human trials exist. Efficacy in humans remains unproven.

Bromantane shows consistent performance-enhancing effects in animal models under various stressful conditions, but no human clinical trials exist to demonstrate efficacy in athletes. Evidence is limited to rodent studies and one meta-analysis that groups bromantane with plant adaptogens without isolating its specific effects.

DMAE has not been proven effective for athletic performance. The single human RCT combined DMAE with ginseng and multiple other ingredients, making it impossible to isolate DMAE's contribution. Observational data shows DMAE is used in pre-workout supplements but provides no efficacy evidence.

Acetyl-L-Carnitine shows plausible but unproven efficacy for athletic performance in humans. The single large RCT in trained cyclists found no improvements in aerobic or anaerobic performance despite reducing blood lactate, while animal studies suggest potential benefits for endurance and mitochondrial function that have not been consistently demonstrated in human athletes.

Glycine supplementation for athletic performance is supported primarily by mechanistic theory and animal studies showing potential benefits for muscle protection and recovery, but human evidence is limited to one small RCT showing null results and observational/review data without controlled comparisons.

5-HTP shows plausible but unproven efficacy for athletic performance in humans. One small RCT demonstrated modest fat mass reduction, but no studies directly measured athletic performance, strength, endurance, or power output in trained athletes.

D-aspartic acid (DAA) supplementation does not reliably improve athletic performance or testosterone levels in human resistance-trained athletes, based on four well-designed randomized controlled trials. Animal studies show potential mechanisms related to D-aspartate metabolism and neurological function, but these do not translate to proven athletic benefits in humans.

Leucine supplementation shows mechanistic promise for muscle protein synthesis and mTOR activation, but human RCT evidence for athletic performance is inconsistent and largely negative. Most well-designed human studies found no additional benefit of leucine supplementation beyond resistance training alone when protein intake is adequate.

One small human RCT suggests L-ornithine may attenuate subjective fatigue and improve performance in females during intense cycling, but evidence is limited to a single study with modest sample size and mixed results across sexes.

TB-500 has extremely limited evidence for athletic performance enhancement. Only one animal study directly examined thymosin β4 (TB-500's active component) as an exercise-induced factor, with no human trials demonstrating performance benefits.

GHK-Cu for athletic performance has no demonstrated efficacy in humans. The only available evidence is a narrative review that mentions GHK-Cu as one of several peptides but provides no specific findings, clinical data, or mechanistic evidence supporting its use for athletic performance.

No rigorous human evidence exists for CJC-1295's effects on athletic performance. Available data consists only of narrative reviews discussing anecdotal online forum reports of use, with no controlled trials, effect measurements, or clinical validation.

Ipamorelin for athletic performance is mentioned only in passing within a narrative review of peptide therapies; no actual efficacy data, human trials, or specific findings for this compound and goal are reported in the available literature.

No evidence demonstrates that kisspeptin supplementation improves athletic performance in humans. Available studies are limited to observational correlations in disease states and mechanistic animal studies exploring reproductive hormones under exercise stress.

Tesamorelin for athletic performance has no proven efficacy. The only available evidence is a 2026 narrative review that mentions tesamorelin among several peptides but provides no specific data, human trials, or efficacy results for this goal.

Only a narrative review of general GH responses to exercise exists for GHRP-2 and athletic performance; no human efficacy studies, animal studies, or RCTs demonstrate that GHRP-2 improves athletic performance.

No human evidence exists for hexarelin and athletic performance. Only a review article mentions that hexarelin may improve cardiac function post-infarction through GH secretion or cardiac GHS receptors, but this is theoretical and requires further investigation.

Melanotan 2 increases physical activity in rodent models through brain melanocortin receptor activation, but no human studies have tested efficacy for athletic performance. Animal evidence is preliminary and does not demonstrate proven effects in humans.

No human evidence exists for cerebrolysin and athletic performance. Only one animal study shows neuroprotective effects against excitotoxicity in mice, which does not directly address athletic performance or physical capacity.

No human evidence exists that elderberry improves athletic performance. A 2019 review acknowledges elderberry's in vitro antioxidant properties but explicitly states that 'research has yet to link the health-related benefits of black elderberry ingestion to exercise performance,' despite theoretical rationale based on polyphenol mechanisms.

A single review article discusses the theoretical risk of iodine depletion through sweat loss during intense exercise, but explicitly states there is 'no case as yet for iodine supplementation' in athletes and no direct evidence that iodine supplementation improves athletic performance.

No evidence exists that copper supplementation enhances athletic performance. The single review explicitly states there are no data to suggest copper supplementation will enhance performance in athletes.

DIM is mentioned only as a 'promising supplement' in a single narrative review about breast cancer treatment, with no efficacy data, human trials, or evidence specific to athletic performance. There is no demonstrated benefit for athletic performance.

No evidence supports apigenin's use for athletic performance. The single identified study examined sedative and neuropharmacological effects in mice, with no relevance to athletic performance outcomes.

Only a 2024 review article exists on PubMed for turkesterone and athletic performance; no human randomized controlled trials, observational studies, or animal experiments are documented in the available literature on this topic. Efficacy for athletic performance is suggested but entirely unproven.

Valerian root for athletic performance has no demonstrated efficacy in humans. The only relevant evidence is a narrative review mentioning valerian as a potential sleep aid for athletes, with no actual efficacy data or human trials reported.

Lemon balm has not been studied for athletic performance in humans. The single available study examined antidepressant effects in rats, which is irrelevant to athletic performance outcomes.

No evidence demonstrates that pregnenolone improves athletic performance in humans. The seven abstracts discuss pregnenolone primarily as a biomarker of steroid metabolism, adrenarche development, and neurological function—not as a performance-enhancing agent.

Forskolin's efficacy for athletic performance is not demonstrated in the available evidence. Only one human RCT included forskolin as part of a multi-ingredient supplement focused on weight loss and body composition in sedentary obese individuals—not athletes or athletic performance. The second article reviews creatine, not forskolin.

CDP-Choline (citicoline) has not been demonstrated to improve athletic performance in humans. Available evidence consists only of animal studies examining nerve regeneration and recovery from traumatic brain injury, with no human trials or athletic performance outcomes reported.

Huperzine A has not been demonstrated to improve athletic performance in humans. The single human RCT found no benefits for cognitive function, neuromuscular performance, or exercise capacity in trained athletes, and actually showed increased perception of difficulty during exercise.

Aniracetam's relevance to athletic performance is not established. The single available abstract is a mechanistic review of synaptic transmission in auditory neurons with no connection to athletic performance, muscle function, or human exercise capacity.

No human evidence exists for vinpocetine and athletic performance. The two available studies are both animal models testing cognitive/neurological outcomes unrelated to athletic performance, making them irrelevant to this health goal.

Centrophenoxine (meclofenoxate) has not been studied in humans for athletic performance. The single available study is a small rat experiment showing dose-dependent and heterogeneous effects on avoidance learning, with higher doses impairing performance—findings with no clear relevance to human athletic performance.

Oxiracetam improved spatial and contextual learning in a single animal model (DBA/2 mice) with learning impairment, but there are no human studies demonstrating efficacy for athletic performance. Animal evidence is insufficient to establish real-world efficacy in athletic contexts.

No human evidence exists for L-carnosine's effects on athletic performance. Available evidence consists of 3 reviews discussing theoretical mechanisms and 1 in-vitro study on cancer cells, none of which demonstrate proven efficacy in athletic contexts.