Dear Dr. Mirkin: Won’t I be a better bicycle rider if I ride hard every day?

If you exercise intensely when your muscles are sore, you put yourself at high risk for injury. The soreness you feel is from
direct muscle damage. Putting great pressure on damaged muscles causes them to tear.  Furthermore, sore muscles significantly
increase your needs for oxygen during exercise and slow you down (European Journal of Applied Physiology, March 2009).  That’s why athletes in every sport use the “hard-easy principle.”  To become a better rider, do a hard session (very fast and/or lots of hills)
so your muscles feel sore on the next day.  Go slowly for as many days as it takes for the soreness to disappear, and then take
another hard day.

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