Various fungi, particularly medicinal mushrooms such as Cordyceps sinensis, Ganoderma lucidum (Reishi), and Hericium erinaceus (Lion’s Mane), have been explored for their potential benefits in supporting aspects of bodybuilding and athletic performance. The scientific validation for these uses is emerging but remains limited, and most evidence is derived from animal studies, small-scale human trials, or studies with methodological limitations.

Cordyceps is the most commonly cited fungus in bodybuilding. Some studies suggest it may enhance ATP production and improve oxygen utilization, potentially increasing endurance during exercise. A few randomized controlled trials have reported modest improvements in exercise capacity and fatigue, but the results are not robust or consistent across all populations.

Reishi and other mushrooms are sometimes promoted for their adaptogenic properties, purportedly helping with recovery, immune support, and stress modulation. However, direct evidence linking these effects to improved muscle hypertrophy or strength is lacking.

Overall, the scientific evidence supporting fungal supplementation for bodybuilding is weak to moderate (rated 2/5). While there are plausible mechanisms and some promising preliminary data, large-scale, high-quality human studies are needed to draw definitive conclusions. As such, the use of fungi in bodybuilding is supported more by emerging science than by tradition or robust clinical data.