What would happen if you were to overwork your muscles?

Question: What would happen if you were to overwork your muscles?
- Keywords:
  exercise,
  muscle,
  overexert,
  overwork
Asked by venusjwh to Mark on 23 Jun 2011.
- Mark Burnley answered on 23 Jun 2011:
  
  Fatigue! The muscles have evolved to be both very powerful but to also be able to sustain low intensity exercise for a long time, but they cannot achieve both. Therefore the price you pay for overworking the muscles is that the force they can produce declines. This is the basic definition of fatigue.

Question: What would happen if you were to overwork your muscles?