21.   Stewart said once he started doing more strenuous activities, his back flared up again, prompting another MRI.

22.   Strenuous physical activity can cause such a rupture.

23.   Strenuous activity, such as shoveling snow, or the exertion of sexual intercourse have been found to trigger heart attacks.

24.   The jockeys who ride them engage in the strenuous outdoor activity wearing long-sleeved Spandex shirts, a protective vest, long pants, a helmet and boots.

25.   There is no hiking, no climbing into rubber boats, in fact no strenuous activity of any kind.

26.   Patients with heart failure -- a disorder caused by weak or inadequate pumping action by the left chamber of the heart -- are often warned against strenuous activity.

27.   Complete recovery follows in four weeks but strenuous activities like tennis should be done only after six to eight weeks.

28.   Doctors said it would be about six weeks after the transplant before he could run or do strenuous activity.

29.   Doctors feared the swimmer might need a transplant and ordered him to stop all strenuous activity for three months.

30.   Heat cramps cause brief, intermittent, often excruciating cramping pain in muscles when strenuous physical activity is done.