Effects of a commercial herbal-based formula on exercise performance in cyclists.
OBJECTIVE
We examined the effects of a commercially marketed herbal-based formula purported to increase endurance on oxygen consumption (VO2) in 17 competitive category III/IV amateur cyclists [mean (SEM) age: 31.1 (1.8) yr; height: 178.5 (1.8) cm; weight: 77.1 (1.6) kg].


METHODS
Each cyclist participated in two (pre/post) cycling tests progressing 25 W.4 min(-1) starting at 100 W administered in a randomized, placebo-controlled, double-blind fashion. The second trial was performed 14 d after the ingestion of a manufacturer recommended loading phase (4 d x 6 caps.d(-1)) and a maintenance phase (11 d x 3 caps.d(-1)). Three treatment capsules contained 1000 mg of Cordyceps sinensis (CS-4) and 300 mg Rhodiola rosea root extract as the primary ingredients; 800 mg of other ingredients included calcium pyruvate, sodium phosphate, potassium phosphate, ribose, and adenosine and 200 mcg of chromium.


RESULTS
Using a 2 x 2 ANOVA, we observed no significant treatment effect for any between or within group variables including peak VO2 [treatment 4.14 (0.2) L.min(-1); placebo 4.10 (0.2) L.min(-1)], time to exhaustion [treatment 38.47 (1.7) min; placebo 36.95 (1.8) min], peak power output (PO) [treatment 300.00 (12.1) W; placebo 290.63 (12.9) W], or peak heart rate. We also observed no differences for any subpeak exercise variable including the PO eliciting 2 mmol.L(-1) blood lactate (BLa) [treatment 201.00 (18.1) W; placebo 167.50 (19.2) W] and 4 mmol.L(-1) BLa [treatment 235.88 (15.8) W; placebo 244.78 (14.9) W], ventilatory threshold, respiratory compensation point, or Vo2 L.min(-1) gross efficiency at each stage.


CONCLUSIONS
A 2-wk ingestion schema of a commercial herbal-based formula is insufficient to elicit positive changes in cycling performance.
Earnest
Conrad P
CP
Center for Human Performance and Nutrition Research, The Cooper Institute Center for Human Performance and Nutrition Research, Dallas, TX 75230, USA. cearnest@cooperinst.org
Morss
Gina M
GM
Wyatt
Frank
F
Jordan
Alexander N
AN
Colson
Sheree
S
Church
Timothy S
TS
Fitzgerald
Yolonda
Y
Autrey
Lance
L
Jurca
Radim
R
Lucia
Alejandro
A
D000328:Adult; D001642:Bicycling / Q000502:physiology*; D032661:Cordyceps / Q000737:chemistry; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D029771:Rhodiola / Q000737:chemistry; D013647:Task Performance and Analysis; D016896:Treatment Outcome
D010936:Plant Extracts