I get a lot of my exercise science news via Alex Hutchinson of Sweat Science. For instance, this interesting item about “the burn” of intense effort — what exactly causes it? Which molecules? According to Pollak et al, it’s protons, lactate, and ATP — and only in concert. “There was essentially no response whatsoever to the individual metabolites,” explains Alex, “so the receptors apparently respond only to the synergistic combination of all three.”
Surprisingly, this fairly unsurprising result is brand new information: the paper’s authors call it “the first demonstration in humans that metabolites normally produced by exercise act in combination to activate sensory neurons that signal sensations of fatigue and muscle pain.”
See Alex’s post on Runner’s World for some more detailed analysis. Here on PainScience.com, I’m citing the Pollak paper in my delayed-onset muscle soreness article.