Powerful Natural Compound For Increasing Muscle Mass & Decreasing Body Fat. Naturally Extracted Ursolic Acid. Ursolic acid-the active ingredient in Ursobolic-is nothing short of amazing. In a very recent landmark study ursolic acid was demonstrated to profoundly increase muscle mass and strength. This effect was found to be mediated in large part by up-regulation of muscle specific IGF-1 expression-basically the key cellular signal in muscle growth. In addition to the muscle mass gains, ursolic acid was found to stimulate substantial fat loss. Ursolic acid has been demonstrated to have several other remarkable physiological effects as well, such as modulation of cortisol through 11b-HSD1 inhibition, inhibition of aromatase enzyme, anti-cancer activity, and stimulation of bone growth. Ursobolic contains nothing but high dose, high quality ursolic acid extracted from natural sources.