[tedmcory77]

Interesting adaptation - Ultramarathoners can adapt to have very high potassium levels. I remember participating in a study with Dr. Stephen Hammer from Indian River State College where we did blood draws, resting heart rates pre and post ultras and they were joking about how high runner's potassium levels were.

[djmips]

Do they adapt to high potassium levels or are selected for their high potassium levels?