Testosterone optimization in athletes has never been more studied — or more misunderstood. A major new evidence-based review from Mayo Clinic researchers cuts through the noise, revealing which strategies actually work and which are wasted effort.
Key Takeaways on Testosterone Optimization in Athletes
• Energy balance is critical: Low energy availability suppresses testosterone.
• Most testosterone boosters lack evidence: Eurycoma longifolia (tongkat ali) and zinc have the strongest support among herbal options
• Resistance exercise increases testosterone: Moderate-to-high intensity with free weights, large muscle groups, and short rest intervals work best
• Sleep quality matters: Testosterone secretion is linked to REM sleep; poor sleep can reduce testosterone by 15%
• Avoid certain exposures: Endocrine-disrupting chemicals, excessive NSAID use, and cold-water immersion may lower testosterone
• Cold water blunts response: Post-exercise cold-water immersion decreased testosterone below pre-exercise levels in controlled trials
Why Athletes Need to Naturally Optimize Testosterone
Testosterone drives muscle protein synthesis, fat-free mass, strength, power, and recovery. The performance link is strong enough that athletes frequently explore both legal and illegal methods to raise levels. But many unknowingly suppress their own testosterone through training and lifestyle choices.
Relative Energy Deficiency in Sport (REDs) — once thought to affect only female athletes — is now recognized across sexes and disciplines. Testosterone deficiency itself shows high prevalence in athletic populations, with estimates ranging from 25% to 80% depending on the sport and population studied (Lazarev et al., 2026).
A comprehensive narrative review published in Sports Health, led by researchers from Mayo Clinic and the University of North Carolina, synthesized hundreds of studies to separate fact from fiction. Here’s what they found.
Nutrition and Energy Balance: The Foundation of Testosterone Optimization
The most fundamental factor in testosterone optimization isn’t a supplement — it’s energy balance. When intake fails to match expenditure, low energy availability (LEA) occurs, disrupting the hypothalamic-pituitary-gonadal (HPG) axis. Decreased GnRH pulses lower LH and FSH, impairing testosterone production directly.
Macronutrient composition also matters. Excessive protein intake — over 3.4 grams per kilogram (1.54 g/lb) per day — combined with low carbohydrates may lower testosterone, likely through increased liver production of sex hormone-binding globulin (SHBG). Low-carb diets also increase REDs risk.
Practically: maintain energy balance, keep carbohydrates adequate, and don’t push protein beyond 3.4 g/kg/day while restricting carbs. Avoid prolonged caloric deficits.
Training Strategies for Testosterone Optimization in Athletes
The evidence is clear. Moderate-to-high intensity resistance exercise increases testosterone — especially when you:
- Use free weights over machines
- Involve large muscle groups (squats, deadlifts, rows)
- Maintain higher training volume
- Keep rest intervals short between sets
The contrast is stark. In young untrained men, unilateral biceps curls produced no testosterone increase, while bilateral knee extensions using identical protocols raised levels significantly. A controlled comparison by Schwanbeck et al. (2020) found free weight training produced significantly greater free testosterone increases than machine training, likely due to greater muscle mass recruited for stabilization.
Endurance Exercise
Acute endurance exercise can also increase testosterone. One trial showed a 31% increase 40 minutes after exhaustive treadmill running; another found a 37% increase during hard endurance training (D’Andrea et al., 2020). The key caveat: high-volume endurance training without sufficient energy intake risks chronic suppression. Adequate fueling makes all the difference.
Sleep: Non-Negotiable for Testosterone Optimization
Testosterone secretion occurs primarily during REM sleep — which explains morning peaks. Reduced sleep duration or quality decreases REM episodes and testosterone production. The numbers are striking: insufficient sleep can reduce testosterone by 15%.
Athletes commonly experience significant sleep issues. One study found 38% of elite athletes were snorers and 8% experienced apneic episodes. Obstructive sleep apnea reaches a 30% prevalence in contact sport athletes (Lazarev et al., 2026).
Maintaining consistent, quality sleep prevents the documented 15% decline. Target 7–9 hours with consistent sleep and wake times, a cool and dark room, and limited screen use before bed. No supplement compensates for chronically poor sleep.
Testosterone Boosters: Mostly Hype
The supplement industry markets countless testosterone boosters. Most lack substantial evidence. The exceptions worth knowing:
- Eurycoma longifolia (tongkat ali): Strongest evidence among herbal options. A meta-analysis of 5 randomized trials confirmed significant testosterone increases through aromatase inhibition, LH boosting, and free testosterone release from SHBG (Leisegang et al., 2022)
- Zinc: Consistently boosts testosterone in deficient individuals and shows benefit even in those with normal levels, through antioxidant activity and steroidogenic enzyme activation.
- Ashwagandha, fenugreek, betaine: Promising but less consistent data.
The risks are real. Testosterone booster consumption has been linked to thromboembolic events, liver injury, and pancreatitis. Up to 50% of testosterone booster samples contain contamination — many with prohibited substances that violate anti-doping rules. Stick to third-party tested products and focus on compounds with actual evidence.
Environmental Factors That Undermine Testosterone Optimization in Athletes
Bisphenol A, phthalates, dioxins, and pesticides disrupt testosterone production and HPG-axis regulation. Phthalate and BPA exposure — common in plastic packaging, fragranced products, and personal care items — correlates with reduced testosterone in men (Meeker & Ferguson, 2014).
Practical steps: use metal and glass containers, reduce fragranced personal care products, and consume fresh produce when possible.
Cold-Water Immersion (CWI)
Popular for recovery, CWI may actively work against testosterone optimization. One study showed testosterone increased 21% after exercise but fell 10% after cold water exposure (Earp et al., 2019). Another trial showed CWI reduced circulating testosterone below pre-exercise baseline. Studies have also observed attenuated strength and hypertrophy when combining resistance training with CWI, potentially through reduced testosterone availability and decreased neural drive.
If testosterone optimization is a priority, skip the ice baths post-training.
NSAIDs and Analgesics
NSAID use reaches up to 90% prevalence in some sports. Ibuprofen may suppress testicular endocrine cell activity and produce a state of compensated hypogonadism (Kristensen et al., 2018). Opioids are more severe — hypogonadism occurs in over 60% of male opioid users through GnRH suppression. Minimize NSAID, acetaminophen, and opioid use when testosterone optimization matters.
Practical Summary: How to Naturally Optimize Testosterone
Do:
- Maintain energy balance with adequate calories and carbohydrates
- Prioritize 7–9 hours of quality sleep
- Train with moderate-to-high intensity free-weight compound movements and short rest intervals
- Limit endocrine-disrupting chemical exposure (plastics, fragranced products)
- Consider eurycoma longifolia or zinc if supplementing — these have the best evidence
Don’t:
- Restrict calories chronically or run very low carbohydrates long-term
- Use cold-water immersion immediately post-resistance training
- Rely on unproven testosterone boosters
- Exceed 3.4 g/kg/day protein while restricting carbohydrates
- Use NSAIDs or opioids habitually
The Bottom Line on Testosterone Optimization in Athletes
Most testosterone-boosting advice is noise. The signal is simpler: eat enough, sleep well, train with intensity, and avoid exposures that suppress production. The fundamentals — energy balance, sleep quality, and smart resistance training — matter far more than exotic supplements or recovery protocols. In fact, some popular recovery methods like cold-water immersion may actively work against you.
For athletes serious about performance, that’s actually good news. You control the factors that matter most.
References
Lazarev A, et al. Testosterone-Optimizing Strategies in Athletes. Sports Health. 2026. https://doi.org/10.1177/19417381251411933
D’Andrea S, et al. Endogenous transient doping: physical exercise acutely increases testosterone levels. J Endocrinol Invest. 2020;43:1349–1371. https://doi.org/10.1007/s40618-020-01251-3
Earp JE, et al. Cold-water immersion blunts and delays increases in circulating testosterone post-resistance exercise. Eur J Appl Physiol. 2019;119:1901–1907. https://doi.org/10.1007/s00421-019-04178-7
Kristensen DM, et al. Ibuprofen alters human testicular physiology to produce a state of compensated hypogonadism. PNAS. 2018;115(4):E715–E724. https://doi.org/10.1073/pnas.1715035115
Leisegang K, et al. Eurycoma longifolia improves serum total testosterone in men: a systematic review and meta-analysis. Medicina. 2022;58(8):1047. https://doi.org/10.3390/medicina58081047
Meeker JD, Ferguson KK. Urinary phthalate metabolites are associated with decreased serum testosterone. J Clin Endocrinol Metab. 2014;99(11):4346–4352. https://doi.org/10.1210/jc.2014-2555
Schwanbeck SR, et al. Effects of training with free weights versus machines on muscle mass, strength, free testosterone, and free cortisol. J Strength Cond Res. 2020;34(7):1851–1859. https://doi.org/10.1519/JSC.0000000000003349
About the Author
Robbie Durand
Robbie Durand is an exercise physiologist and science writer specializing in evidence-based fitness and nutrition research. With over 15 years of experience translating peer-reviewed studies into actionable advice, Robbie helps readers make informed decisions about training, supplementation, and body composition.
