Ancient Chinese medicine and traditional Russian medicine both incorporated schisandra as a mental and physical health aid(2). Ancient Chinese medicine employed logic believing the five flavors meant properties benefitting the five major visceral organs; improved liver function and bodily detoxification have indeed been shown in modern times(1). The Soviet Union was really looking into its physical and mental endurance qualities by the 1960s and found that its nutrients "help to reduce fatigue and oxidative stress by contributing to normalized nitric oxide and cortisol levels in the blood" - combatting fatigue, allowing longer time at work, and lessening errors made due to exhaustion. Modern studies show properties aiding sleep and energy(2).
Further possible benefits of schisandra include: relief of depression and anxiety; mild sedative effects; boosting metabolism and therefore weight loss; suppression of blood pressure; relief of motion sickness; eye health; and digestive support. Note: Huge quantities shouldn't be consumed, especially for long periods. Dried fruit should be limited to 3 grams a day. Very high doses may raise risk of epilepsy, peptic ulcers, or increased intercranial pressure. The adaptogenic compounds mean schisandra isn't recommended for pregnant or breastfeeding mothers - the baby might receive too high stimulation(1).
References:
1. Staughton, John. "18 Surprising Benefits Of Schisandra." Organic Facts: Let's Get Healthy Together. Organic Information Services Pvt Ltd. 14 Feb. 2020. Web. 19 May 2021. https://www.organicfacts.net/schisandra.html.
2. "Ingredient Spotlight: Schisandra Berry." Isagenix Health. Isagenix Worldwide, Inc. 4 May 2021. Web. 19 May 2021. https://www.isagenixhealth.net/ingredient-spotlight-schisandra-berry/.