PRT had a large positive effect on strength ( 41 trials , 1955 participants ) , but there was statistical heterogeneity that was not explained by differences in study quality , participant characteristics or the exercise program .
REVIEW ER 'S CONCLUSIONS PRT appears to be an effective intervention to increase strength in older people and has a positive effect on some functional limitations .
However , the effect of this intervention on more substantive outcomes such as measures of disability or HRQOL remains unclear .
BACKGROUND Muscle weakness in old age , is associated with physical disability and an increased risk of falls .
Progressive resistance strength ( PRT ) training exercises ( i.e. movements performed against a specific external force that is regularly increased during training ) are design ed to increase strength in older people .
OBJECTIVES To assess the effect of PRT on measures of physical disability , functional limitation and impairment in older people  , and identify adverse events .
Treating disability in knee osteoarthritis with exercise therapy: a central role for self-efficacy and pain.
OBJECTIVE To examine the effects of aerobic and resistance exercise on self-efficacy beliefs in older adults with knee osteoarthritis ( OA ) and to determine whether self-efficacy and knee pain mediated the effects of the treatments on stair time performance and health perceptions . METHODS Measures of self-efficacy , knee pain , stair climbing performance , and health perceptions were collected prior to r and omization and again at an 18-month followup in older adults with knee OA who were assigned to 1 of 3 treatment conditions : aerobic exercise , resistance training , or health education control .  All analyses were conducted on the intention-to-treat principle . RESULTS Both exercise treatments increased self-efficacy for stair climbing in comparison to the health education control group . Both knee pain and self-efficacy mediated the effect of the treatments on stair climb time , whereas only knee pain mediated health perceptions . CONCLUSIONS The findings suggest that control beliefs and changes in physical symptoms such as knee pain are important outcomes in physical activity programs with patients who have OA of the knee . Moreover , these variables mediate the effects that such programs have on disability and health perceptions
PRT had a large positive effect on strength ( 41 trials , 1955 participants ) , but there was statistical heterogeneity that was not explained by differences in study quality , participant characteristics or the exercise program .
REVIEW ER 'S CONCLUSIONS PRT appears to be an effective intervention to increase strength in older people and has a positive effect on some functional limitations .
However , the effect of this intervention on more substantive outcomes such as measures of disability or HRQOL remains unclear .
BACKGROUND Muscle weakness in old age , is associated with physical disability and an increased risk of falls .
Progressive resistance strength ( PRT ) training exercises ( i.e. movements performed against a specific external force that is regularly increased during training ) are design ed to increase strength in older people .
OBJECTIVES To assess the effect of PRT on measures of physical disability , functional limitation and impairment in older people  , and identify adverse events .