Jogging in middle age.

The risks and possible cardiovascular benefits of beginning a programme of jogging in middle age are critically reviewed. A lifelong habit of vigorous exercise results in lower incidence rates of ischaemic heart disease. There is, however, no direct evidence that the same is true when sedentary middle-aged people decide to begin exercise. Exercise can have a beneficial effect on the risk factors for ischaemic heart disease but whether this reduces the likelihood of death from ischaemic heart disease remains unproven. There are approximately 12 sudden deaths per 100 000 male joggers in the USA attributable to jogging annually, while almost a third of all joggers report a musculoskeletal injury in a 12-month period.