1.   Consumer advocates said the group might be legitimate, but urged potential donors to exercise caution before contributing.

2.   Did you exercise before joining the company fitness center?

3.   Exercising before flights helps to offset the effects on the body of reduced air pressure, and aerobic exercise afterwards helps to reoxygenate it.

4.   He said he always tried to exercise before going to bed and avoided going to bed on a full stomach.

5.   The mental benefits of walking were especially significant, researchers said, because the senior citizens had not exercised regularly before joining the study.