Ashwagandha (Withania somnifera) is a promising herb, with recent studies suggesting the positive use as an adjunct to strength training. The compound is used in Ayurveda, the traditional medicine of India, to improve general age-related health, wellbeing, and vitality. Positive health outcomes including reduction in cortisol levels, anti-inflammation, anti-anxiety, anti-arthritis, increased testosterone, reduction in menopause symptoms, and increased strength have been observed with Ashwagandha supplementation.
As an adaptogen, Ashwagandha contains phytonutrients that allow the body to adapt to physical or mental stress, while regulating metabolism. Adaptations that may occur include regulating system functions, increased resistance to the ongoing state of stress, and enhanced body function to perform at a higher level. Supplementation of Ashwagandha adjunct to resistance training may provide athletes with these adaptations to promote increased muscle mass, muscle strength and improve overall performance.
A randomised controlled trial compared the adaptations of 57 male participants that underwent 8 weeks of resistance training. 29 participants received the Ashwagandha treatment of 300mg twice per day, and 28 received a placebo. The treatment group observed a greater increase (compared to placebo) in the 1RM of both bench press and leg extension following the 8-week trial. The Ashwagandha group experienced significant muscle mass increases in arm, chest, and leg muscle groups. Testosterone levels were also measured pre- and post-intervention. The Ashwagandha supplementation group observed a greater increase in serum testosterone when compared to the placebo group. To assess muscle recovery, serum creatine kinase levels were measured. Faster muscle tissue repair and greater recovery was observed in the Ashwagandha group due to the smaller increase in blood creatine kinase levels. Greater recovery allows individuals to continue training with greater voluntary muscle force and increased amount of training during a specific timeframe, allowing them to achieve increased muscle mass and strength.
Two functions of Ashwagandha that may be responsible for these gains is the increase in testosterone and decrease in cortisol levels. Testosterone stimulates muscle protein synthesis and prevents protein degradation, causing an anabolic effect in muscle. When secreted during exercise (or high stress states), cortisol causes muscle protein breakdown which is detrimental to muscle growth. Research suggests Ashwagandha decreases levels of cortisol in the blood, providing a beneficial environment for muscles to grow.
Ashwagandha has also proven to promote ATP generation by increasing creatine levels and decreasing activity of the Mg2+ dependent ATPase enzyme that breaks down ATP. These two functions work simultaneously to promote energy production and mitochondrial energy levels.
Ashwagandha is responsible for greater and more rapid recovery post-exercise due to its antioxidant and anti-inflammatory effects. Damage caused by free radicals in the muscle and nervous system may be reversed by the antioxidant properties of Ashwagandha. Potential reduction of delayed onset muscle soreness (DOMS) due to decreased muscle injury can allow the individual to resume proper training earlier with the ability to maximise voluntary force production. Anti-anxiety effects of Ashwagandha may see results in increased recruitment and coordination of muscles due to enhanced focus.
Ashwagandha has promising effects on the VO2 max and cardiorespiratory endurance. The endurance potential of an athlete can be measured using VO2 max, determining their ability to utilize oxygen during intense exercise. Studies show the compounds ability to improve aerobic capacity by increasing red blood corpuscles (RBC) and haemoglobin count, promoting the capacity of oxygen transport through the blood to working muscles.
The promising research surrounding Ashwagandha and adaptogens suggest the potential to enhance performance of athletes. Overall, the research suggests Ashwagandha may be beneficial for general vitality and delaying aging processes by promoting antioxidant, anti-inflammatory, decreased anxiety, increased testosterone, and increased strength properties. Conduction of further research will allow scientists to observe the full potential of this compound.
Efficacy of Ashwagandha (Withania somnifera [L.] Dunal) in improving cardiorespiratory endurance in healthy athletic adults: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4687242/
Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial: https://www.tandfonline.com/doi/full/10.1186/s12970-015-0104-9