When Does Ashwagandha Make Sense—and When Doesn’t It? + Exact Dosage

What is ashwagandha, and why are athletes interested in it?

Ashwagandha (Withania somnifera) is an adaptogen from Ayurveda. Root extracts have been linked to better stress management, sleep, and certain physical performance markers—strength, endurance, and recovery. The best-studied products are standardized root extracts with withanolide content around 5–10%. Results, however, vary depending on the extract type, dose, and the participants’ training status. (PMC)

What research says about strength, muscle, and VO₂max

• Strength and muscle: A randomized, double-blind study (8 weeks, 57 men) using 300 mg of root extract twice daily showed greater strength gains (bench press, leg extension), larger increases in limb girths, and a reduction in fat compared with placebo. (PubMed)
• Strength + endurance in women and men: A newer clinical study (2024) with 600 mg/day of a standardized extract (>5% withanolides) alongside resistance training improved both 1RM and VO₂max versus placebo, with no serious adverse events reported. (PMC)
• Evidence summary: A systematic review and Bayesian meta-analysis of 13 studies (up to 2020) concluded that ashwagandha was more effective than placebo for improving strength/power, cardiorespiratory fitness, and some markers of fatigue and recovery; it also notes the need for more studies in trained populations. (PMC)

When does ashwagandha make sense for performance?

• You have high stress or poor sleep and you train—lower stress and better sleep may indirectly improve performance and recovery. (ods.od.nih.gov)
• You’re a recreational to intermediate trainee looking for small but measurable improvements in strength or VO₂max with consistent training. (PMC)
• You want a standardized protocol with a short time horizon (8–12 weeks) and can monitor how your body responds.

When probably not? (Or only after talking to your doctor)

• Pregnancy, breastfeeding, children. European authorities (BfR, RIVM) and reviews advise against use in these groups due to limited safety data and reports of adverse effects. (RIVM)
• Liver disease or concurrent hepatotoxic medications; case reports of liver injury exist. (PMC)
• Thyroid disorders (or thyroid hormone therapy)—ashwagandha may alter T3/T4/TSH levels. (ods.od.nih.gov)
• Hormone-sensitive prostate cancer, use of sedatives, antidiabetics, antihypertensives, or immunosuppressants—risk of interactions. (ods.od.nih.gov)
• You want certainty for long-term use. Safety evidence beyond ~3 months is limited. (ods.od.nih.gov)

Dosage by goal (standardized extracts)

The doses below apply to standardized root extracts. With combined extracts (root + leaf), the effective dose is often lower due to a higher withanolide content.

• Stress/sleep: 300–600 mg/day (often 300 mg twice daily). Start with an evening dose (150–300 mg) and watch for drowsiness. (ods.od.nih.gov)
• Strength and hypertrophy: 300 mg twice daily with food for 8 weeks alongside resistance training. (PubMed, PMC)
• Endurance/VO₂max: 600 mg/day (typically 300 mg in the morning + 300 mg in the evening) for at least 8 weeks. (PMC)
• Alternative—more highly standardized extracts (e.g., 10% withanolides): sometimes 125–250 mg/day. A practical dosage overview lists 150–600 mg/day depending on standardization and goal. (Examine)

Tips for use:
Take with food (helps reduce nausea). Start conservatively (e.g., 300 mg/day in the first week), then move to the target dose. After 8–12 weeks, take a 2–4 week break and reassess effects and tolerability (since long-term data are lacking). (ods.od.nih.gov)

How to choose a quality product

• On the label, look for Withania somnifera (root extract) and withanolide standardization (e.g., ≥5%).
• Avoid “proprietary blends” that don’t disclose exact amounts.
• Prefer independent testing (e.g., third-party certification) and transparent sourcing.
• Don’t exceed the recommended dose; different extraction methods and plant parts can differ in potency and risk profile. 

Side effects and safety

The most commonly reported are digestive upset, drowsiness, headaches, and skin reactions; more rarely, liver injury and effects on the thyroid have been described. If you have liver/thyroid disease or take the medications listed above, speak with your doctor before starting supplementation. If you’re sensitive, stop use if you develop jaundice, dark urine, extreme fatigue, or an unexplained itchy rash, and seek medical care. (ods.od.nih.gov, PMC)

Combine or not?

Ashwagandha works differently than creatine or caffeine, so it’s commonly combined (creatine for the phosphagen system, caffeine for acute performance; ashwagandha more via stress/sleep and potentially anti-inflammatory and antioxidant mechanisms). Still, monitor overall stimulation (with caffeine) and GI tolerance.

A quick 8-week plan for a recreational strength trainee

1. Week 1: 300 mg in the evening with food.
2. Weeks 2–8: 300 mg in the morning + 300 mg in the evening with food.
3. Training: 3–4× per week, progressive overload; sleep 7–9 h.
4. After week 8: take a 2–4 week break; evaluate strength (1RM/5RM), measurements, and subjective recovery. (PubMed, PMC)

When will you see an effect?

In studies, changes tend to appear after 6–8 weeks of consistent use alongside training and basic lifestyle factors (sleep, nutrition). For performance, expectations should be modest but measurable (especially in less trained individuals). (PMC)

Videos for a quick overview (to watch outside the article)

“How Ashwagandha Helps Performance, Testosterone & Sleep” – an overview of mechanisms and studies, explained clearly.

“3 Supplements You Aren’t Taking BUT Should Consider!” – a segment on ashwagandha in a training context.

Summary

Ashwagandha may provide a small benefit for strength, VO₂max, and recovery—especially if it also improves sleep and reduces stress. Recreational athletes tend to benefit most from 600 mg/day of a standardized root extract for 8 weeks. However, it’s not for everyone—avoid it (or use only with medical guidance) during pregnancy, breastfeeding, with liver/thyroid conditions, or when taking certain medications. Long-term safety beyond three months is still unclear. (PubMed, PMC, ods.od.nih.gov)

Sources

1. Wankhede S. et al. “Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial” – J Int Soc Sports Nutr (2015). https://pubmed.ncbi.nlm.nih.gov/26609282/
2. Bonilla D.A. et al. “Effects of Ashwagandha (Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-Analysis” – J Funct Morphol Kinesiol (2021). https://pmc.ncbi.nlm.nih.gov/articles/PMC8006238/
3. Verma N. et al. “Effects of Ashwagandha standardized root extract on muscle size, strength and VO₂max” – F1000Research (2024). https://pmc.ncbi.nlm.nih.gov/articles/PMC11234080/
4. NIH Office of Dietary Supplements. “Ashwagandha: Is it helpful for stress, anxiety, or sleep?” (updated 2 May 2025). https://ods.od.nih.gov/factsheets/Ashwagandha-HealthProfessional/
5. BfR – German Federal Institute for Risk Assessment. “Ashwagandha: food supplements with potential health risks” (10 Sep 2024). https://www.bfr.bund.de/cm/349/ashwagandha-food-supplements-with-potential-health-risks.pdf
6. RIVM (Netherlands). “Risk assessment of herbal preparations containing Withania somnifera (Ashwagandha)” (2024). https://www.rivm.nl/bibliotheek/rapporten/2024-0029.pdf
7. Lubarska M. et al. “A Case Report of Ashwagandha-Induced Liver Injury” – Am J Case Rep (2023). https://pmc.ncbi.nlm.nih.gov/articles/PMC10002162/
8. Examine.com. “Ashwagandha — benefits, dosage, side effects”. https://examine.com/supplements/ashwagandha/