Preview
Hüseyin Akbulut, MSc (2026). Ergogenic Aids: What’s Worth Taking and What Isn’t. Sporeus. Retrieved, October 15, 2026. https://sporeus.com/en/science/ergogenic-aids-evidence/
Ergogenic Aids: What’s Worth Taking and What Isn’t
The global sports supplement market is projected to exceed $50 billion annually, yet the vast majority of products sold lack meaningful clinical evidence for performance enhancement. Athletes navigate a landscape where legitimate evidence-based ergogenic aids share shelf space with expensive placebos. This article provides a rigorous, evidence-tiered ranking of the most commonly used supplements in competitive and recreational sport.
Table of Contents
Tier 1: Strong Evidence, Meaningful Effect
A small number of supplements have been tested in multiple well-designed randomized controlled trials and show consistent, meaningful performance benefits. These are the only supplements that warrant routine consideration by athletes.
Caffeine is the most thoroughly studied ergogenic aid in sport science. Hundreds of trials across endurance, strength, and team sports demonstrate consistent performance improvements of 2–4% at doses of 3–6 mg/kg body mass consumed 30–60 minutes before exercise. Caffeine works primarily by blocking adenosine receptors in the brain, reducing perception of effort, and increasing motor unit recruitment. It is effective across all fitness levels and most exercise modalities. Importantly, lower doses (2–3 mg/kg) provide substantial benefits with fewer side effects — tremor, anxiety, GI distress, and sleep disruption — than higher doses. Caffeine tolerance develops with habitual high consumption, but a 4–7 day withdrawal period before competition restores full sensitivity.
Creatine monohydrate is the most evidence-supported supplement for strength and power sports. Over 500 studies confirm its efficacy for increasing phosphocreatine stores in muscle, improving performance in repeated high-intensity efforts lasting 5–30 seconds, supporting lean mass accretion, and potentially aiding recovery. A loading phase of 20 g/day for 5 days (or 3–5 g/day for 28 days without loading) achieves muscle saturation. Creatine monohydrate is the recommended form — not creatine ethyl ester, buffered creatine, or other novel variants, which show no superiority and cost significantly more.
Dietary nitrates (from beetroot juice or supplemental nitrate) elevate plasma nitric oxide, reducing oxygen cost of exercise and improving exercise efficiency. Meta-analyses report improvements in time-trial performance of 1–3% in endurance athletes. The effective dose is approximately 5–9 mmol of nitrate (400–500 mL of concentrated beetroot juice) consumed 2–3 hours before exercise. Benefits appear most pronounced in less-trained individuals and in hypoxic or altitude conditions. Elite athletes show smaller but still measurable effects.
Beta-alanine increases muscle carnosine content, which buffers hydrogen ions during high-intensity exercise and delays acidosis-related fatigue. Effects are most pronounced in efforts lasting 1–4 minutes at maximal intensity — rowing, middle-distance running, cycling time trials, and repeated sprint sports. Standard dosing is 3.2–6.4 g/day; the characteristic tingling sensation (paresthesia) can be mitigated by splitting into smaller doses. Benefits require 4–6 weeks of supplementation to manifest.
Tier 2: Moderate Evidence, Context-Dependent
| Supplement | Evidence Level | Best Use Case | Notes |
|---|---|---|---|
| Sodium bicarbonate | Moderate-Strong | High-intensity 1–7 min events | GI side effects limit use; enteric-coated may help |
| HMB (β-hydroxy β-methylbutyrate) | Moderate | Untrained individuals, muscle preservation | Minimal benefit in trained athletes |
| Vitamin D | Moderate | Deficient athletes (<30 nmol/L) | Correction of deficiency improves performance; supplementing sufficient athletes shows no benefit |
| Iron | Moderate | Iron-deficient athletes | Only beneficial when deficiency confirmed via blood panel |
| Tart cherry juice | Moderate | Post-exercise recovery, sleep | Reduces DOMS markers; anthocyanins may blunt adaptation if used chronically |
| Omega-3 fatty acids | Moderate | Anti-inflammatory, cognitive function | Weak direct performance evidence; strong health evidence |
Tier 3: Insufficient or Negative Evidence
The following supplements are heavily marketed but lack sufficient evidence to recommend for sport performance:
- Branched-chain amino acids (BCAAs): When total daily protein intake is adequate, BCAA supplementation provides no additional benefit to muscle protein synthesis or recovery. Leucine from whole protein sources is superior. BCAAs are expensive and unnecessary when dietary protein targets are met.
- Glutamine: Despite widespread marketing, oral glutamine supplementation does not meaningfully increase muscle glutamine levels or improve performance, immune function, or recovery beyond placebo in athletes consuming adequate protein.
- Collagen/gelatin: Mechanistically interesting for tendon health (gelatin + vitamin C pre-exercise may support collagen synthesis), but direct tendon injury prevention or performance evidence remains preliminary.
- Testosterone boosters: Commercial “test booster” products — typically blends of zinc, magnesium, herb extracts — show no clinically meaningful effect on testosterone levels or anabolic outcomes in healthy athletes.
- Fat burners: Thermogenic supplements beyond caffeine (the only evidence-based thermogenic) have no consistent evidence of meaningful fat loss acceleration and carry cardiovascular risk with stimulant blends.
Safety, Testing, and Practical Prioritization
Supplement contamination is a genuine concern for competitive athletes. Studies consistently find that 10–25% of commercial sports supplements contain substances that could trigger a positive doping test, due to undisclosed additions or manufacturing cross-contamination. Athletes subject to anti-doping testing should use only products certified by independent third-party testing programs such as Informed Sport, NSF Certified for Sport, or Cologne List.
The most rational supplement strategy is hierarchical: first optimize diet, training, sleep, and recovery — all of which produce larger performance returns than any supplement. Then consider Tier 1 supplements relevant to your sport’s energy system demands. Use timing and dose protocols from the research literature rather than product label recommendations, which typically overstate required quantities.
No supplement corrects a poor diet, insufficient sleep, or suboptimal training. But within an already strong foundation, caffeine, creatine, nitrates, and beta-alanine represent genuine, evidence-supported tools — the rare cases where the science matches the marketing claim.
References
- Maughan RJ, Burke LM, Dvorak J, et al. (2018). IOC consensus statement: dietary supplements and the high-performance athlete. British Journal of Sports Medicine, 52(7): 439-455. doi:10.1136/bjsports-2018-099027
- Guest NS, VanDusseldorp TA, Nelson MT, et al. (2021). International Society of Sports Nutrition position stand: caffeine and exercise performance. Journal of the International Society of Sports Nutrition, 18(1): 1. doi:10.1186/s12970-020-00383-4
- Kreider RB, Kalman DS, Antonio J, et al. (2017). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition, 14: 18. doi:10.1186/s12970-017-0173-z
Hüseyin Akbulut is the founder of Sporeus and author of THRESHOLD (EŞİK), a 540-page Turkish-language book on endurance science.
- 540pp THRESHOLD Book
- MSc Sport Sciences
- Marmara University
Tier 1: Strong Evidence, Meaningful Effect
A small number of supplements have been tested in multiple well-designed randomized controlled trials and show consistent, meaningful performance benefits. These are the only supplements that warrant routine consideration by athletes.
Tier 2: Moderate Evidence, Context-Dependent Supplement Evidence Level Best Use Case Notes Sodium bicarbonate Moderate-Strong High-intensity 1–7 min events GI side effects limit use; enteric-coated may help HMB (β-hydroxy β-methylbutyrate) Moderate Untrained individuals, muscle preservation Minimal benefit in trained athletes Vitamin D Moderate Deficient athletes (<30 nmol/L) Correction of deficiency improves performance; supplementing sufficient athletes shows no benefit Iron Moderate Iron-deficient athletes Only beneficial when deficiency confirmed via blood panel Tart cherry juice Moderate Post-exercise recovery, sleep Reduces DOMS markers; anthocyanins may blunt adaptation if used chronically Omega-3 fatty acids Moderate Anti-inflammatory, cognitive function Weak direct performance evidence; strong health evidence Tier 3: Insufficient or Negative Evidence
The following supplements are heavily marketed but lack sufficient evidence to recommend for sport performance:
Safety, Testing, and Practical Prioritization
Supplement contamination is a genuine concern for competitive athletes. Studies consistently find that 10–25% of commercial sports supplements contain substances that could trigger a positive doping test, due to undisclosed additions or manufacturing cross-contamination. Athletes subject to anti-doping testing should use only products certified by…
