"Diosgenin" (a spirostenol) is a relatively underutilised resource, a plant steroid just like turkesterone and ecdysterone which goes all but unnoticed in the fitness community. Found in yams, ginger and fenugreek, it's one of the most readily available natural steroid hormone mimics, so much so that it has been used throughout history as a raw material to commercially produce testosterone, estrogens, and progesterone. However, even in its natural form without structural modification into our endogenous hormones, it still elicits a broad range of beneficial effects on training and could be said to be one of the most promising natural potentiators of exercise known.
Much like turkesterone and ecdysterone, diosgenin is able to encourage a lean phenotype by acting directly in muscle and fat tissues. Diosgenin is taken up by satellite cells and encourages their differentiation and fusion with skeletal muscle cells, enhancing muscle diameter and strength when paired with exercise. Alongside this, diosgenin works directly in muscle fibres to encourage expression of AMPK, an 'exercise regulator' which encourages heightened metabolism, uptake of sugar into muscles and enhanced utilisation of fat as an energy source via fatty acid oxidation.
Diosgenin also enhances production of DHEA in the body, an androgen which encourages GLUT4 translocation in muscle cells to enhance their uptake of sugar as an energy source, and diosgenin may also encourage increases in the levels of other androgens including dihydro-testosterone (DHT). Curiously, diosgenin is so closely related to DHEA that when yam is added during the soy sauce fermentation process, it is converted into DHEA. This begs serious questions regarding the legality of fermented yam or ginger products including soy sauces, soy pastes, kimchi, and even pickled ginger, as DHEA is schedule 4 appendix D, classified as an anabolic androgenic steroid in Australia just like its sibling testosterone. Nonetheless, diosgenin itself is not restricted and is legally a foodstuff as an extract of yams, making it a 'dietary hormone'.
Another aspect of diosgenin which it is more well known for is its capability to promote bone strength, by encouraging the replication of bone-repairing osteoblasts, as well as promoting collagen production in bone. Collagen production is also promoted in skin to encourage repair. Further, diosgenin can reduce inflammation and oxidative stress, encouraging enhanced stamina, as well as promoting healthy metabolism, particularly in fat cells via PPAR receptors.
Other beneficial features of diosgenin include its ability to encourage formation of new blood vessels during healing processes, which would include training, as well as its ability to reduce mental stress and promote healthy brain tissue which could potentially boost focus and performance.
For those looking to broaden their supplement regime, diosgenin is an obvious choice, with many beneficial effects on both health and fitness.