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. 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.
Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial
Withania somnifera (ashwagandha) is a prominent herb in Ayurveda. This study was conducted to examine the possible effects of ashwagandha root extract consumption on muscle mass and strength in healthy young men engaged in resistance training.
In this 8-week, randomized, prospective, double-blind, placebo-controlled clinical study, 57 young male subjects (18–50 years old) with little experience in resistance training were randomized into treatment (29 subjects) and placebo (28 subjects) groups. Subjects in the treatment group consumed 300 mg of ashwagandha root extract twice daily, while the control group consumed starch placebos. Following baseline measurements, both groups of subjects underwent resistance training for 8 weeks and measurements were repeated at the end of week 8. The primary efficacy measure was muscle strength. The secondary efficacy measures were muscle size, body composition, serum testosterone levels and muscle recovery. Muscle strength was evaluated using the 1-RM load for the bench press and leg extension exercises. Muscle recovery was evaluated by using serum creatine kinase level as a marker of muscle injury from the effects of exercise.
Compared to the placebo subjects, the group treated with ashwagandha had significantly greater increases in muscle strength on the bench-press exercise (Placebo: 26.4 kg, 95 % CI, 19.5, 33.3 vs. Ashwagandha: 46.0 kg, 95 % CI 36.6, 55.5; p?=?0.001) and the leg-extension exercise (Placebo: 9.8 kg, 95 % CI, 7.2,12.3 vs. Ashwagandha: 14.5 kg, 95 % CI, 10.8,18.2; p?=?0.04), and significantly greater muscle size increase at the arms (Placebo: 5.3 cm 2 , 95 % CI, 3.3,7.2 vs. Ashwagandha: 8.6 cm 2 , 95 % CI, 6.9,10.8; p?=?0.01) and chest (Placebo: 1.4 cm, 95 % CI, 0.8, 2.0 vs. Ashwagandha: 3.3 cm, 95 % CI, 2.6, 4.1; p?< ?0.001). Compared to the placebo subjects, the subjects receiving ashwagandha also had significantly greater reduction of exercise-induced muscle damage as indicated by the stabilization of serum creatine kinase (Placebo: 1307.5 U/L, 95 % CI, 1202.8, 1412.1, vs. Ashwagandha: 1462.6 U/L, 95 % CI, 1366.2, 1559.1; p?=?0.03), significantly greater increase in testosterone level (Placebo: 18.0 ng/dL, 95 % CI, -15.8, 51.8 vs. Ashwagandha: 96.2 ng/dL, 95 % CI, 54.7, 137.5; p?=?0.004), and a significantly greater decrease in body fat percentage (Placebo: 1.5 %, 95 % CI, 0.4 %, 2.6 % vs. Ashwagandha: 3.5 %, 95 % CI, 2.0 %, 4.9 %; p?=?0.03).
This study reports that ashwagandha supplementation is associated with significant increases in muscle mass and strength and suggests that ashwagandha supplementation may be useful in conjunction with a resistance training program.