THANK YOU FOR VISITING SWEATSCIENCE.COM!
As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.
- Alex Hutchinson (@sweatscience)
Of the sessions that I attended at the Sport Nutrition Conference in Canberra last month, the one that was most unfamiliar to me was about nutrition and the brain, presented by Romain Meeusen of the Free University in Brussels. He covered a lot of ground about the various ways that the brain interacts with the periphery, but what caught my attention the most was a series of experiments using anti-depressants.
The original experiments tried giving substances like bupropion (Wellbutrin), reboxetine and Ritalin to cyclists, and didn’t see any improvement in 30min time trial performance after a 60min warm-up. BUT when they increased the temperature from 18 C to 30 C, all of the sudden these drugs produced massive improvements in performance — from 39.8 to 36.4 minutes for (I think) bupropion. Ritalin was even bigger — a seven-minute improvement.
At 18 C, most of the cyclists hit a maximum core temperature of about 39.5 C, but at 30 C they were up over 40.0 C when taking the drugs — almost to the point where the trials had to be halted for ethical reasons. As Meeusen put it, their “safety brake” didn’t work, so they were capable of pushing into the danger zone without feedback from the central nervous system. This is essentially what happened to Tom Simpson (who was taking amphetamines) on Mont Ventoux in 1967, he said.
So what does this mean? Well for starters, buproprion, which was recently taken off WADA’s banned list, should be put back on it. To Tim Noakes, this would undoubtedly sound like evidence that fatigue is governed by a “central governor.” Meeusen, as far as I can tell, doesn’t see it that way. He says “fatigue is likely to be an integrated phenomenon with complex interaction among central and peripheral factors.” Which basically means “it’s complicated.” Hard to disagree with that.