PRT results in improvements to muscle strength and some aspects of functional limitation , such as gait speed , in older adults .
However , based on current data , the effect of PRT on physical disability remains unclear .
Further , due to the poor reporting of adverse events in trials , it is difficult to evaluate the risks associated with PRT
BACKGROUND The aim of this systematic review was to quantify the effectiveness of progressive resistance strength training ( PRT ) to reduce  physical disability in older people .
Resistance training over 2 years increases bone mass in calcium-replete postmenopausal women.
Underst and ing the stress/strain relationship between exercise and bone is critical to underst and ing the potential benefit of exercise in preventing postmenopausal bone loss . This study examined the effect of a 2-year exercise intervention and calcium supplementation ( 600 mg ) on bone mineral density ( BMD ) in 126 postmenopausal women ( mean age , 60 + /- 5 years ) . Assignment was by block r and omization to one of three groups : strength ( S ) , fitness ( F ) , or nonexercise control ( C ) . The two exercise groups completed three sets of the same nine exercises , three times a week . The S group increased the loading , while the F group had additional stationary bicycle riding with minimal increase in loading .  Retention at 2 years was 71 % ( 59 % in the S group , 69 % in the F group , and 83 % in the C group ) , while the exercise compliance did not differ between the exercise groups ( S group , 74 + /- 13 % ; F group , 77 + /- 14 % ) . BMD was measured at the hip , lumbar spine , and forearm sites every 6 months using a Hologic 4500 . Whole body BMD also was measured every 6 months on a Hologic 2000 . There was no difference between the groups at the forearm , lumbar spine , or whole body sites . There was a significant effect of the  strength program  at the total ( 0.9 + /- 2.6 % ; p < 0.05 ) and intertrochanter hip site ( 1.1 + /- 3.0 % ; p < 0.01 ) . There was a significant time and group interaction ( p < 0.05 ) at the intertrochanter site by repeated measures . This study shows the effectiveness of a progressive strength program in increasing bone density at the clinical ly important hip site . We concluded that a strength program could be recommended as an adjunct lifestyle approach to osteoporosis treatment or used in combination with other therapies
PRT results in improvements to muscle strength and some aspects of functional limitation , such as gait speed , in older adults .
However , based on current data , the effect of PRT on physical disability remains unclear .
Further , due to the poor reporting of adverse events in trials , it is difficult to evaluate the risks associated with PRT
BACKGROUND The aim of this systematic review was to quantify the effectiveness of progressive resistance strength training ( PRT ) to reduce  physical disability in older people .