CORDYCEPS SINENSIS- AND RHODIOLA ROSEA-BASED SUPPLEMENTATION IN MALE CYCLISTS AND ITS EFFECT ON MUSCLE TISSUE OXYGEN SATURATION

Headnote

ABSTRACT. Colson, S.N., F.B. Wyatt, D.L. Johnston, L.D. Autrey, Y.L. FitzGerald, and C.P. Earnest. Cordyceps sinensis- and Rhodiola rosea-based supplementation in male cyclists and its effect on muscle tissue oxygen saturation J. Strength Cond. Res. 19(2):358-363. 2005.-Cordyceps sinensis (Cs) and Rhodiola rosea (Rr) are herbs used in traditional Chinese medicine to treat a multitude of ailments as well as to enhance performance. The purpose of this research was to examine the effects of a formula containing Cs and Rr (Cs-Rr) on circulatory dynamics, specifically muscle tissue oxygen saturation (StO^sub 2^), in male subjects during maximal exercise. This study followed a double blind, randomized, placebo-treatment, pre-post test design. Capsules were administered to 8 subjects who were randomly assigned to 1 of 2 groups. The treatment group received Cs-Rr, and the control group received a placebo. All subjects performed 2 exercise stress tests to volitional fatigue on a cycle load ergometer. There were no significant (p ≤ 0.05) differences in StO^sub 2^ slope, StO^sub 2^ threshold (StO^sub 2T^), VO^sub 2^max, ventilatory threshold (V^sub T^), or time to exhaustion (T^sub E^) between or within the treatment or control group. In conclusion, Cs-Rr did not significantly enhance StO^sub 2^.

KEY WORDS. herb, vasodilation, blood flow, oxygen delivery

INTRODUCTION

Ergogenic aids and herbal supplementation have been used for a variety of purposes. Athletes as well as diseased patients have credited supplementation with benefits in performance and quality of life, respectively. Cordyceps sinensis (Cs) is a Chinese herb extracted from a nontoxic mushroom. One of the benefits purported by Cs research is the enhancement of circulatory dynamics. Cs has been shown to increase vasodilation, which in turn facilitates oxygen delivery (QO^sub 2^) to the working tissue, allowing for a more efficient use of O2 (6, 11). Rhodiola rosea (Rr) is an herb used in traditional Eastern European and Asian medicine to stimulate the nervous system. It has been reported to enhance work performance and time to exhaustion (T^sub E^) by suppressing fatigue (4, 19, 20).

The immediate and pronounced increase in muscle blood flow, which is associated with vasodilation, at the onset of exercise is a well-known phenomenon (13). However, in addition to vasodilation and antioxidation activity, it has been shown that muscle blood flow is dependant upon relative oxygen...