Muscle function of women aged 65-89 years meeting two sets of health criteria.

This study compared the isometric strength, leg extensor power, and some potentially related functional abilities of elderly women selected for exercise studies according to two sets of readily applicable exclusion criteria. The health status criteria ("healthy" and "medically stable") differed principally in respect to duration of freedom from diagnosed or symptomatic disease, medication taken and Body Mass Index. Fifty "healthy" women and fifty "medically stable" women, aged 65 to 89 and evenly distributed over the age range, were recruited through local and national newspapers. There was no significant difference between the two health groups in strength or power. However, the women in the "medically stable" group were heavier and had more difficulty in rising from a chair. The strength of the relationships between strength, power and kneel rise time were very dependent on body weight for the "medically stable" women but not for the "healthy" women. The health criteria used to classify elderly subjects must be clearly specified so that there may be easier interpretation of results from future studies. This is especially true in studies where body weight might be important.