Ginseng has been around a long time with mixed results in many research studies. This is probably due to poor studies that did not address important issues related to the species, doses, and duration of ginseng supplementation. A well-controlled study in the Journal of Strength and Condition Research investigated a specific type of ginseng known as Panax notoginseng (Chinese ginseng). The study was a placebo-controlled design that involved subjects consuming both Panex notoginseng (1,350 g/day for 30 days) and a placebo on two different occasions. The ginseng was analyzed by HPLC and shown to contain significant amounts of bioactive compounds such as sanchinosides and gypenosides. Other studies of this nature have not verified the bioactives in the ginseng studied. After each 30-day period of supplementation, an endurance test to exhaustion was performed. Ginseng supplementation led to a significant improvement in endurance performance (about 7 min), that was associated with a lower oxygen uptake and decreased blood pressure. This indicates improved efficiency, that is, subjects were able to perform more work with less stress on the heart.
Liang MT, Podolka TD, Chuang WJ. Panax notoginseng supplementation enhances physical performance during endurance exercise. J Strength Cond Res. 2005 Feb;19(1):108-14.