performances will suffer. When you race all-out too often, your body secretes less cortisol, a hormone that aids recovery, and it slowly becomes immune to the hormone's effects. The result is constant fatigue and a depressed immune system. A good rule of thumb
pace, then drop the pace by two to three seconds for each successive 400mRecovery: Jog for four minutes between repeats.Ed Eyestone is an exercise physiologist and two-time Olympic marathon runner.
