Exercises for a healthy back can be divided into three basic groups:
1. Strengthening: repeated muscle contractions until the muscle becomes tired.
2. Stretching or Flexibility: slow, sustained lengthening of the muscle.
3. Aerobic: steady exercise using large muscle groups.
All of these exercises should be performed slowly and comfortably to avoid injury. When performing strengthening and flexibility exercises, remember to breathe naturally and without holding your breath; exhale during exertion and inhale during relaxation.
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