Taste receptors inside a muscle

Dallen:

HR is stable, can drop a couple of beats when this happens, about 8 beats away from the max usually. What is interesting - HR correlates with running pace very well, however, the pace at which this sensation comes, and the failure to maintain the pace for longer can come at several different paces/heart rates on different days. E.g. 5:20/165, 5:30/163, 5:40/158. I'd image HR is a good predictor of lactate levels, so it is probably not lactate related. Or could be, maybe my ability to tolerate lactate varies from day to day. I have noticed that lactic tolerance workouts help push that critical pace up. But at the same time, lactic tolerance workout generates a lot of neural output and recruits a lot of fibers. My recent explosions seem to have a similar effect. So maybe it is something in the muscle recruitment area after all.