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 exercise and bone turnover in elderly men and women.
PURPOSE This investigation examined the effect of 6 months of high- or low-intensity resistance exercise ( REX ) on bone mineral density ( BMD ) and biochemical markers of bone turnover in adults aged 60 - 83 yr . METHODS Sixty-two men and women ( 68.4 + /- 6 yr ) were stratified for strength and r and omly assigned to a control ( CON , N = 16 ) , low-intensity ( LEX , N = 24 ) , or high-intensity ( HEX , N = 22 ) group . Subjects participated in 6 months of progressive REX training . Subjects trained at either 50 % of their one repetition maximum ( 1-RM ) for 13 repetitions ( LEX ) or 80 % of 1-RM for 8 repetitions ( HEX ) 3 times x wk(-1 ) for 24 wk . One set each of 12 exercises was performed . 1-RM was measured for eight exercises . BMD was measured for total body , femoral neck , and lumbar spine by dual energy x-ray absorptiometry ( DXA ) . Serum levels of bone-specific alkaline phosphatase ( BAP ) , osteocalcin ( OC ) , and pyridinoline cross-links ( PYD ) were measured . RESULTS 1-RM significantly increased for all exercises tested for both the HEX and LEX groups ( P < and = 0.050 ) . The percent increases in total strength ( sum of all eight 1-RMs ) were 17.2 % and 17.8 % for the LEX and HEX groups , respectively . Bone mineral density ( BMD ) of the femoral neck significantly ( P < 0.05 ) increased by 1.96 % for the HEX group . No other significant changes for BMD were found . OC increased by 25.1 % and 39.0 % for the LEX and HEX groups , respectively ( P < 0.05 ) . BAP significantly ( P < 0.05 ) increased 7.1 % for the HEX group . CONCLUSION These data indicate high-intensity REX training was successful for improving BMD of the femoral neck in healthy elderly subjects . Also , these data suggest REX increased bone turnover , which over time may lead to further changes in BMD
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 .