Ashwagandha increases stamina, meta-study
For endurance athletes and longevitants [individuals who want to live a hundred years while remaining in perfect health and read weird websites like this], ashwagandha has become even more interesting than it already was. According to a recent meta-study by Spanish researchers from the University of Extremadura, supplementation with ashwagandha extracts increases VO2max. VO2max is the main determinant of stamina. And if you increase your VO2max, you probably also slow down aging.
Ashwagandha is the cash cow of Ayurveda. Traditional Indian healers have used the plant as a tonic and anti-aging agent for centuries. Now that modern studies have shown that ashwagandha helps strength athletes gain more strength, increases testosterone levels and improves body composition and women's sexuality, supplements containing Withania somnifera are more popular than ever.
Scientists still do not know exactly what exactly the main active substances in ashwagandha are. Most attention is paid to the withanolides, but it cannot be excluded that ashwagandhanolide and the withanamides also play a significant role in the ergogenic effects of ashwagandha.
The Spaniards tracked 5 studies in the medical literature in which researchers gave subjects ashwagandha and then measured the effect on VO2max. They aggregated the result together, and analyzed them again.
The outcome of the meta-study is clear. Ashwagandha increases VO2max in an undeniable way.
The figure below is simplified. Click on it for a full version.
It is also remarkable that the study with the most neutral results - Tripathi 2006 - was also the study with the lowest dose: 330 milligrams of ashwagandha extract per day. Maybe that's really too little to boost VO2max.
Click on the figure below for a larger version.
"Ashwagandha supplementation might improve the VO2max in athlete and non-athlete people", the Spaniards conclude. "The analyzed studies used oral administration of Ashwagandha which varied between 2 and 12 weeks with intakes between 300 to 1000 mg/day."
"Due to the limited number of studies included in this systematic review and meta-analysis, further research is needed to confirm the effects and the recommended dose."
Speed up your sprints (and increase your VO2max) with ashwagandha 19.04.2011