If bodybuilders or other strength athletes take ashwagandha they build up more muscle and lose fat more quickly, write Indian researchers in the Journal of the International Society of Sports Nutrition. The researchers tested a daily dose of 600 mg ashwagandha extract on men were doing weight training for the first time in their lives.
The researchers got 57 men aged between 18 and 50 to do weight training three times a week. The men had never done resistance training before and were all given the same routine.
Half of the men took a placebo; the other half took ashwagandha. The researchers used KSM-66, a water-based extract that consisted of 5 percent withanolides. [ksm66ashwagandhaa.com] The subjects took a capsule containing 300 mg KSM-66 every day on waking and another capsule before going to bed.
KSM-66 is a product manufactured by Shri Kartikeya Pharma and Ixoreal BioMed. It's not clear to what extent these companies financed this study.
Measurements using a measuring tape showed that the subjects who took ashwagandha built up more muscle mass than the subjects in the placebo group.
The percentage of fat declined in both groups, but the ashwagandha users lost more than the members of the placebo group. The researchers used the bioelectrical impedance method to measure the fat percentage. [We have our doubts about the reliability of this method, as we also do about the method the researchers used to measure muscle mass.]
The table above reveals how ashwagandha might increase the effectiveness of resistance training. The testosterone level of the subjects who had taken ashwagandha was higher than that of the subjects in the placebo group.
Another possibility is that ashwagandha protects muscle cells against muscle breakdown. The post-workout concentration of the enzyme creatine-kinase in the blood went down during the experiment in both groups, but the decrease was bigger in the subjects that had taken ashwagandha. The more creatine-kinase in the blood, the more damage the muscle cells have incurred.
"This study confirms previous data regarding the adaptogenic properties of ashwagandha and suggests it might be a useful adjunct to strength training", the researchers concluded.
"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."
According to the study, ashwagandha had no side effects.
Products that contains the recommended amount of Ashwagandha
Human study: Ashwagandha boosts testosterone level 19.06.2014
Ashwagandha: more muscle strength, more lean body mass & lower fat percentage19.12.2013
Forty percent more testosterone with Ashwagandha 19.07.2009