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Root rage: The impact of ashwagandha on muscle

So called “adaptogens” like ashwagandha are typically studied for stress-easing potential. A randomized trial looked into this popular herb for a different purpose: bolstering adaptations to weight training.

Study under review: Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial.


Being stressed sucks. However, stress has its benefits. It’s been long-known that a moderate amount of psychological stress can improve physical performance. And, as many of our readers probably know, exercise is a stressor on the body that actually strengthens it in the long run.

Recently there has been increased interest in a class of herbal supplements known as “adaptogens” (some common ones are shown in Figure 1). Adaptogens are purported to help the body cope with both physical and mental stressors. Well-known examples of adaptogens include ginseng and rhodiola.

Figure 1: Some common adaptogens

Another adaptogen that may help in this context is the root of Withania somnifera, also known as ashwagandha, Indian Ginseng, or Winter Cherry. Ashwagandha is a perennial shrub that grows primarily in parts of Asia, and is a member of the nightshade family. Ashwagandha root is classified in traditional Indian Ayurvedic medicine as a rasayana, or a rejuvenator. Initial research on ashwagandha has indicated that it may live up to this classification. Supplementation of ashwagandha in humans may decrease[1] the stress hormone cortisol, increase[2] testosterone, and even improve[3] cardiovascular performance. Yet many of these studies were published in lower-impact journals, which may somewhat call into question the validity of the results.

With that many effects to its name, it is plausible that ashwagandha may also be beneficial for strength training. This is the question the authors of the study under review intended to answer.

Ashwagandha is classified under the loose umbrella of “adaptogen,” meaning an herbal supplement that helps the body cope with stressors. The purpose of this study was to determine if ashwagandha supplementation could improve strength gains during resistance training.

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