title: Dietary supplement with a combination of Rhodiola crenulata and Ginkgo biloba enhances the endurance performance in healthy volunteers.
abstract: OBJECTIVE
  To determine whether the ingestion of a herbal supplement called Rhodiola-Gingko Capsule (RGC) would enhance the endurance performance of healthy volunteers and change relevant hormones in a favorable manner.
  
  
  METHODS
  Seventy healthy male volunteers (age ranges from 18 to 22 years old) were randomly assigned to RGC group (35 cases, each capsule containing 270 mg herbal extracts, 4 capsules per day) or placebo group (35 cases, equivalent placebo preparation) for 7 weeks using computer produced digital random method. The endurance performance, serum testosterone and cortisol levels were measured at the baseline and the endpoint.
  
  
  RESULTS
  Sixty-seven subjects (34 in the RGC group and 33 in the placebo group) completed a 7-week treatment. The RGC group displayed a significantly greater baseline-to endpoint increase in maximal oxygen uptake (VO(2max)) than placebo group in both absolute (P=0.020) and relative values (P=0.023). At the endpoint, the serum cortisol level was unchanged in the RGC group compared with the baseline, but it was significantly elevated in the placebo group (P<0.05). The endpoint ratio of testosterone to cortisol, a surrogate for overtraining and fatigue in endurance exercises, was also indifferent compared with the baseline in the RGC group, but significantly decreased in the placebo group (P<0.05).
  
  
  CONCLUSIONS
  The combined herbal supplement of Rhodiola and Gingko could improve the endurance performance by increasing oxygen consumption and protecting against fatigue.
authors: School of Chinese Medicine, the University of Hong Kong, Hong Kong, China.
authors: Zhang-jin
authors: ZJ
authors: Zhang
authors: Yao
authors: Y
authors: Tong
authors: Jun
authors: J
authors: Zou
authors: Pei-jie
authors: PJ
authors: Chen
authors: Ding-hai
authors: DH
authors: Yu
mesh_terms: D000293:Adolescent; D004359:Drug Therapy, Combination; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage* / Q000009:adverse effects; D005221:Fatigue / Q000188:drug therapy*; D020441:Ginkgo biloba; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D055048:Integrative Medicine; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects*; D010807:Physical Endurance / Q000187:drug effects*; D010919:Placebos; D029771:Rhodiola; D013739:Testosterone / Q000097:blood; D055815:Young Adult
chemical_list: D004365:Drugs, Chinese Herbal; D010919:Placebos; D013739:Testosterone; D006854:Hydrocortisone