Eight weeks of supplementation with the Ayurvedic herb in combination with a resistance training program were associated with significantly lower levels of exercise-induced muscle damage, significantly greater levels of testosterone, and a significantly greater decrease in body fat, compared with placebo.
Indian researchers also report in the Journal of the International Society of Sports Nutrition that participants in the ashwagandha group also experienced significantly greater muscle size increases in the arms and the chest.
The flagship herb of Ayurveda
Ashwagandha has been gaining traction in the mainstream US market with consumers embracing its wide-ranging body of health benefits, which include supporting stress, cognitive function, sleep, metabolic wellness, adrenal function, sports performance, and more.
According to a monograph from the American Herbal Pharmacopoeia (AHP), the herb has a history of use in ayurvedic medicine that dates back as much as 4,000 years to the teaching of renowned scholar Punarvasu Atreya, and in subsequent works that make up the ayurvedic tradition. The name of the herb derives from Sanskrit, and means “smells like a horse”, which refers to the strong smell of the root which is said to be redolent of horse sweat or urine.
The new study used Ixoreal Biomed’s KSM-66 Ashwagandha and Kartikeya Baldwa, Director of Ixoreal Biomed, said that ashwagandha root is prominently advocated as an ergogenic aid to improve strength and vitality in traditional Ayurveda texts.
“While there are other published studies demonstrating the effectiveness of ashwagandha in increasing strength and stamina, this is the first study using a standardized, branded ashwagandha extract and demonstrating significant effects on muscle strength, size and recovery,” he said. “This study also corroborates the findings from a previously published clinical study, showing KSM-66 to be effective in increasing natural testosterone production in men.”
Study details
The researchers recruited 57 young men to participate in their clinical trial. The men were aged between 18 and 50 and had limited experience in resistance training. They were randomly assigned to receive either placebo or supplements of ashwagandha root extract (600 mg per day, KSM-66 Ashwagandha) for eight weeks. All the men trained during the intervention period and improvements were recorded in both groups. However, significantly greater improvements were observed in the ashwagandha root group, said the researchers.
Participants in the ashwagandha root group displayed significantly greater increases in muscle strength on the bench-press exercise and the leg-extension exercise, they said.
In addition, testosterone levels were also significantly higher in the ashwagandha group, compared to the placebo group.
“This study confirms previous data regarding the adaptogenic properties of ashwagandha and suggests it might be a useful adjunct to strength training,” wrote the researchers.
“This study has the following limitations which should lead us to interpret the findings with some caution: the subjects are untrained and moderately young, the sample size of 50 is not large and the study period is of duration only 8 weeks. Research studying the possible beneficial effects of ashwagandha needs to be conducted for longer periods of time and for different populations including females and older adults of both genders.”
Commenting on the study’s findings, Ixoreal’s Baldwa said: “From the scientific literature, we know that the ashwagandha root increases energy production, increases cognitive focus, and promotes balance in the body to increase or decrease key hormone levels to bring them to appropriate levels. These effects are perhaps responsible for the strong results we see in this study.”
Source: Journal of the International Society of Sports Nutrition
2015, 12:43, doi:10.1186/s12970-015-0104-9
“Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial”
Authors: S. Wankhede, et al.