|
Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "
|
|
||||||||
16.11.2013 |
|
|
Echinacea not an effective endurance sports supplement, says study
In 2007 American sports scientists discovered that a daily 8 g Echinacea supplementation boosted EPO synthesis in humans. The researchers also found indications that Echinacea boosts endurance capacity.
Interesting findings like this beg for follow-up studies – and that's what the sports scientists at Georgia State University have now provided. They gave nine well-trained runners a daily dose of 8 g Echinacea in supplement form for a period of six weeks.
The preparation the researchers used came from Puritan's Pride.
The subjects took a dose of 2 g Echinacea four times a day.
A control group of 7 runners took a placebo.
Before and after the supplementation period the researchers measured the subjects' maximal oxygen uptake, their haemoglobin and haematocrit levels, and their endurance capacity in an exhaustion test that involved the subjects exercising for as long as possible at a high level of exertion.
The table below shows that there was no sign at all of any performance enhancing effect.
So it seems that Echinacea has no effect in trained runners, the researchers conclude. They do suggest though that Echinacea may enhance performance when used over a longer period and in higher doses.
High doses of Echinacea become ineffective when used for periods longer than several weeks, and, when used for longer than that, they actually become counterproductive. That's why we wonder whether the researchers didn't use Echinacea for too long even.
Another older study, in the Journal of Strength and Conditioning Research, provides indications that this might be the case. [J Strength Cond Res. 2012 Jul;26(7):1928-33.] In that study researchers at Arkansas State University gave recreational athletes 8 g Echinacea every day for four weeks.
The Echinacea boosted the subjects' maximal oxygen uptake by a small amount, probably because the extract boosted their EPO synthesis. The supplement had no effect on the red blood cells.
The figure below shows that the effect of the Echinacea was strongest on day 14. After that the effect declined.
In none of the studies were subjects given extra iron. In the competitive cycling world you often hear that EPO only attains an optimal effect when cyclists also take iron supplements.
Maybe researchers would obtain better results if they had measured the effect of this dose of Echinacea after three weeks, and if they had given their subjects extra iron too.
Source:
More:
|
|
