The Claim

Eight weeks of high-intensity interval training (HIIT) results in approximately a 5% increase in maximal oxygen uptake (VO2max) measured in absolute terms (L/min) among healthy young adult males; however, this improvement is not significantly different between participants receiving ashwagandha supplementation versus placebo, and relative VO2max (ml/kg/min) does not demonstrate significant improvement due to modest increases in body weight.

Source: Effects of an 8-week high intensity interval training (HIIT) and ashwagandha supplementation on aerobic capacity, muscle oxygenation and haematological parameters in healthy men

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
61score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

After doing 8 weeks of intense interval exercise, young men can breathe in about 5% more oxygen per minute, but taking an ashwagandha supplement doesn't help any more than a fake pill, and because they might gain a little weight, their oxygen use relative to body weight doesn't really improve.

See the scientific wording

Eight weeks of HIIT training increases maximal oxygen uptake (VO2max) in absolute terms (L/min) by approximately 5% in healthy young men, but this improvement is not significantly different between ashwagandha and placebo groups, and relative VO2max (ml/kg/min) does not show significant improvement due to modest body weight increases.

What the research says

1 study
  1. Study: Effects of an 8-week high intensity interval training (HIIT) and ashwagandha supplementation on aerobic capacity, muscle oxygenation and haematological parameters in healthy men

    This study tested exactly what the claim describes - 8 weeks of HIIT training with either ashwagandha or placebo pills. The results show that both groups improved their VO2max (absolute), but there was no meaningful difference between the ashwagandha and placebo groups, which matches the claim perfectly.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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