Effects Of Combined Rhodiola And Cordyceps On VO 2 Max, Blood Glucose, And Lactate

Abstract

Rhodiola and Cordyceps are two common herbal supplements that have been shown to increase VO2 max and exercise performance, but limited research has examined the combined effects. PURPOSE: To determine the combined effects of Rhodiola and Cordyceps (R+C) supplementation, compared to Rhodiola alone (R) and placebo (PL), on VO2 max, blood glucose and lactate concentrations. METHODS: 13 physically active college students (7M, 6F; Mean ± SD; 21.08 ± 1.55 yrs, 22.60 ± 2.29 kg/m2) completed three conditions in a counterbalanced, crossover, double-blinded fashion; 1) PL (250 mg calcium), 2) R (250 mg Rhodiola), 3) R+C (250 mg Rhodiola + 225 mg Cordyceps). In response to each condition, VO2 max (assessed by Bruce Protocol), blood glucose and lactate (via fingerstick) were examined using an ANOVA. RESULTS: There was no significant condition effect for VO2 max between PL, R, and R+C (P=0.80; Mean ± SD; 50.42 ± 8.75, 51.08 ± 7.44, 50.76 ± 7.64 mL/kg/min). There was no significant condition x time interaction for blood glucose (P=0.99). However, compared to PL, blood glucose was significantly higher in R+C (P=.047; LSM ± SEM; 104.97 ± 2.91, 113.08 ± 2.91 mg/dL). There was no significant condition or condition x time interaction in blood lactate concentrations between conditions (Ps>0.05). CONCLUSION: Our preliminary data suggest that R+C had no effect on VO2 max or blood lactate concentrations, but increased blood glucose concentrations. Future studies are needed to examine ventilatory threshold and other markers of exercise performance in response to these supplements.