Effect of Cs-4 (Cordyceps sinensis) on exercise performance in healthy older subjects: a double-blind, placebo-controlled trial.

Objective: The objective of this study was to examine the effect of Cs-4 (Cordyceps sinensis) on exercise performance in healthy elderly subjects.

Design: Twenty (20) healthy elderly (age 50-75 years) subjects were enrolled in this double-blind, placebo-controlled, prospective trial. The subjects were taking either Cs-4 333 mg or placebo capsules 3 times a day for 12 weeks.

Measurement: Subjects received baseline screening including physical examination and laboratory tests. Maximal incremental exercise testing was performed on a stationary cycle ergometer using breath-by-breath analysis at baseline and at the completion of the study.

Results: After receiving Cs-4 for 12 weeks, the metabolic threshold (above which lactate accumulates) increased by 10.5% from 0.83 +/- 0.06 to 0.93 +/- 0.08 L/min (p < 0.02) and the ventilatory threshold (above which unbuffered H(+) stimulates ventilation) increased by 8.5% from 1.25 +/- 0.11 to 1.36 +/- 0.15 L/min. Significant changes in metabolic or ventilatory threshold were not seen for the subjects in the placebo group after 12 weeks, and there were no changes in Vo(2) max in either group.

Conclusion: This pilot study suggests that supplementation with Cs-4 (Cordyceps sinensis) improves exercise performance and might contribute to wellness in healthy older subjects.