Decrease in Performance
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If you're working out responsibly, you should see your performance improve or at least stay the same. If you notice your performance dropping or you feel especially exhausted by your usual workout, you might be overtraining. Kaeding says this is difficult to evaluate – some researchers are even trying to create blood tests for it – so the best thing to do for now when your performance dips is err on the side of caution and give yourself a break.