Phytoecdysteroids, such as 20-hydroxyecdysone (20E) derived from plants like Rhaponticum carthamoides (maral root) and Spinacia oleracea (spinach), have gained interest as potential athletic and exercise aids. The rationale for their use is primarily based on preclinical and limited human research examining their effects on muscle mass, strength, and physical performance. Animal studies have shown that phytoecdysteroids can promote protein synthesis and muscle hypertrophy, possibly via activation of the PI3K/Akt signaling pathway, which is also targeted by anabolic steroids.

In humans, the available clinical evidence is limited and of modest quality. A small number of studies—such as Isenmann et al. (2019, Archives of Toxicology)—have suggested that ecdysteroid supplementation may enhance muscle mass and strength gains in resistance-trained men compared to placebo, but the sample sizes are small and methodologies vary. The World Anti-Doping Agency (WADA) has listed ecdysteroids as substances of interest, reflecting their potential impact on performance.

However, the overall evidence is still preliminary, with a lack of large-scale, long-term, well-controlled human trials. There is also insufficient data regarding safety and optimal dosing. Thus, while there is some scientific basis for their use as exercise aids, the quality and quantity of evidence supporting efficacy in athletes is limited, warranting a moderate-low evidence rating.