Date of Award
Fall 12-2011
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Human Performance and Recreation
Committee Chair
Michael J. Webster
Committee Chair Department
Human Performance and Recreation
Committee Member 2
Timothy P. Scheett
Committee Member 2 Department
Human Performance and Recreation
Committee Member 3
Geoffrey M. Hudson
Committee Member 3 Department
Human Performance and Recreation
Committee Member 4
Gregor Kay
Committee Member 4 Department
Human Performance and Recreation
Abstract
The purpose of the present study was to investigate the effect of six weeks of oral Echinacea supplementation on serum erythropoietin (EPO) and erythropoietic status, plasma nitric oxide [NO], submaximal endurance exercise performance, and maximal oxygen uptake (V˙O2max). Twenty-four males (mean ± SE): age = 25.2 ± 1.4 yr, height = 178.1 ± 1.4 cm, mass = 78.1 ± 1.6 kg, percent body fat = 12.7 ± 0.9 %, V˙Omax = 52.9 ± 0.9 mL·kg-1·min-1 were randomly grouped using a matched-pair, double-blind design and self-administered 8,000 mg·d-1(5 × 400 mg × 4 times·d-1) of either Echinacea purpurea (ECH) (n=12) or placebo (PLA) (n=12) for 42 consecutive days. Blood samples were collected and analyzed for EPO, red blood cells (RBCs), hemoglobin (Hb), hematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), nitrite, and total nitrite (nitrite/nitrate) concentrations. Graded exercise tests were performed on a treadmill to assess submaximal exercise performance and maximal oxygen uptake (V˙O2max). Separate 2 × 4 (Group × Time) factorial ANOVA with repeated measures were used to determine statistical differences with significance set at p ≤ .05. There were no statistically significant (p > .05) interaction, group or time effects observed for EPO, erythropoietic status markers, nitrite, nitrate, nitrite/nitrate, submaximal V˙O2, submaximal heart rate (HR), or V˙O2max. The present study indicates that six weeks of oral ECH supplementation in apparently healthy, recreationally active, males with above average fitness status (V˙O2max = 52.9 ± 0.9 mL˙kg-1˙min-1 ), does not enhance EPO, erythropoietic status, [NO], or endurance exercise performance. These findings are in contrast with previous reports of Echinacea supplementation and any explanation for these differences, including the role that training and/or physical fitness level of participants, is unclear and speculative.
Copyright
2011, Tyler David Martin
Recommended Citation
Martin, Tyler David, "The Effect of Six Weeks of Oral Echinacea Supplementation on Erythropoiesis, Nitric Oxide Production, and Exercise Performance" (2011). Dissertations. 703.
https://aquila.usm.edu/dissertations/703
Included in
Dietetics and Clinical Nutrition Commons, Kinesiology Commons, Public Health Education and Promotion Commons