Research
Adherence
Dietary supplements carry a significant risk of inadvertent doping violations due to contamination, despite widespread use among athletes.
Be extremely cautious with dietary supplements. Many are contaminated with banned substances. Consult a qualified professional and use third-party tested supplements to avoid accidental doping violations.
GoodRefutesHIGH confidence
In 2000–2001, a study of 634 different supplements from 13 countries found that 94 (14.8%) contained undeclared steroids, banned by WADA.
Why this rating
Supported by multiple studies showing contamination rates.
Source
Role of nutrition in performance enhancement and postexercise recovery
Kathryn L. Beck et al. · Open Access Journal of Sports Medicine · 2015
DOI 10.2147/oajsm.s33605
narrative_reviewCited 216×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Carbohydrate loading (10–12 g/kg/day for 36–48 hours) improves performance by 2–3% and delays fatigue in endurance events lasting longer than 90 minutes.Good
- Post-exercise protein intake (approx. 20g) maximizes muscle protein synthesis, but its impact on strength or hypertrophy is equivocal if total daily protein intake is adequate.Good
- Training with low carbohydrate availability ('train-low') enhances metabolic adaptations (e.g., mitochondrial enzyme activity) but does not improve performance compared to training with high carbohydrate availability.Moderate
Related findings · Adherence
- Regular physical activity (at least 150 minutes/week of moderate-intensity) reduces all-cause and cardiovascular mortality by 20-30% and lowers the risk of type 2 diabetes by 25-35%.Strong
- Increasing physical activity from a sedentary lifestyle to an active one in middle adulthood significantly reduces the risk of coronary events compared to remaining sedentary.Strong
- Resistance exercise is the only intervention capable of consistently restoring muscle function and strength in sarcopenia, partially overcoming age-related anabolic resistance.Strong
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →