A quick test for overtraining syndrome involves a simple determination of your resting heart rate (RHR). Every morning, simply take your heart rate and average out your beats per minute over a three day test. Watch the clock for 15 seconds. When you count the beats do not count the first beat. Take the total number of beats in 15 seconds and multiply it by 4. That will be your RHR. It is important to record your RHR prior to getting out of bed and before any activity.
If your heart rate stays elevated more than 10 beats per minute (bpm) for three days or is greater than 15 bpm than your average, you are likely to be suffering from overtraining.
To reverse the effects of overtraining, add more sleep to your schedule and attempt to eat 20-50 grams more protein per day. Maintain a lighter workout schedule until your normal RHR returns.Resource: OnFitness Magazine