If you want to see serious improvements in your fitness level, you have to push your body to the limit – then do it again. The processes that makes your muscles feel sore also strengthens them and being winded trains your body to better conserve oxygen. Though pushing your physical boundaries is healthly, pushing them too far can be dangerous and debilitating. The key is to know when you're overdoing it.
Dr. Christopher Kaeding, professor of orthopedics at Ohio State University and head team physician for the Buckeyes offers some insight.
If your physical performance is lagging, there is a good chance that you feel a little mentally off as well. While physical activity is often linked to decreases in depression and anxiety, overtraining can increase depression, irritability, and moodiness. A common sentiment amongst athletes who are overtrained is that they lose their enthusiasm for their sport and competitive spirit.
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