Cordyceps

What it does

Cultivated Cordyceps militaris (rich in cordycepin, an adenosine analogue) is studied for aerobic capacity and fatigue resistance. Several small trials show modest VO2max and time-to-exhaustion improvements, likely via oxygen use and cellular energy pathways, though the exact mechanism is unproven.

What the research says

• Improved VO2max and time to exhaustion in several small trials

  Evidence: moderate. One trial: +4.8 ml/kg/min VO2max and about 70 seconds longer time to exhaustion over 3 weeks of supplementation; multiple trials report 7-11% time-to-exhaustion gains at 1-3 g/day for 3-12 weeks

• Reduced exercise fatigue markers such as blood lactate

  Evidence: emerging. Reported in select trials; a 2016 systematic review found no VO2max improvement in already-trained athletes

• Attenuated post-exercise muscle-damage markers (creatine kinase)

  Evidence: emerging. Nakamura et al.: lower CK rise with C. militaris, but no improvement in 5 km running performance

Cleanest performance evidence among medicinal mushrooms, replicated across multiple small trials, but samples are small, effects modest, one positive trial used a multi-mushroom blend, and trained athletes show little benefit.

Is it worth it?

Reasonable for endurance athletes or recreational exercisers seeking marginal gains at 1-3 g/day; the effect is small and not worth it for sedentary buyers expecting a transformation.