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 .
Exercise and weight loss in obese older adults with knee osteoarthritis: a preliminary study.
OBJECTIVE The purpose s of this pilot study were to determine if a combined dietary and exercise intervention would result in significant weight loss in older obese adults with knee osteoarthritis , and to compare the effects of exercise plus dietary therapy with exercise alone on gait , strength , knee pain , biomarkers of cartilage degradation , and physical function . DESIGN Single-blind , two-arm , r and omized clinical trial conducted for 24 weeks . SETTING A university health and exercise science center . PARTICIPANTS Twenty-four community-dwelling obese older adults aged > or = 60 years , body mass index > or = 28 , knee pain , radiographic evidence of knee osteoarthritis , and self-reported physical disability . INTERVENTION R and omization into two groups : exercise and diet ( E&D ) and exercise alone ( E ) . Exercise consisted of a combined weight training and walking program for 1 hour three times per week . The dietary intervention included weekly sessions with a nutritionist utilizing cognitive-behavior modification to change dietary habits to reach a group goal of an average weight loss of 15 lb ( 6.8 kg ) over 6 months . MEASUREMENTS All measurements were conducted at baseline and 3 and 6 months , except for synovial fluid analysis , which was obtained only at baseline and 6 months . In addition , weight was measured weekly in the E&D group . Physical disability and knee pain were measured by self-report and physical performance was measured using the 6-minute walk and stair climb tasks . Biomechanical testing included kinetic and kinematic analysis of gait and isokinetic strength testing . Synovial fluid was analyzed for levels of total proteoglycan , keratan sulfate , and interleukin-1 beta . RESULTS Twenty-one of the 24 participants completed the study , with one dropout in the E&D group and two in the E group . The E&D group lost a mean of 18.8 lb ( 8.5 kg ) at 6 months compared with 4.0 lb ( 1.8 kg ) in the E group ( P = .01 ) . Significant improvements were noted in both groups in self-reported disability and knee pain intensity and frequency as well as in physical performance measures . However , no statistical differences were found between the two groups at 6 months in knee pain scores or self-reported performance measures of physical function . There was no difference in knee strength between the groups , with both groups showing modest improvements from baseline to 6 months . At 6 months , the E&D group had a significantly greater loading rate ( P = .03 ) and maximum braking force ( P = .01 ) during gait . There were no significant between-group differences in the other biomechanical measures . Synovial fluid sample s were obtainable at both baseline and 6 months in eight participants ( four per group ) . The level of keratan sulfate decreased similarly in both groups from an average baseline of 96.8 + /- 37.1 to 71.5 + /- 23 ng/microg total proteoglycan . The level of IL-1 decreased from 25.3 + /- 9.8 at baseline to 8.3 + /- 6.1 pg/mL. The decrease in IL-1 correlated with the change in pain frequency ( r = -0.77 , P = .043 ) . CONCLUSIONS Weight loss can be achieved and sustained over a 6-month period in a cohort of older obese persons with osteoarthritis of the knee through a dietary and exercise intervention . Both exercise and combined weight loss and exercise regimens lead to improvements in pain , disability , and performance . Moreover , the trends in the biomechanical data suggest that exercise combined with diet may have an additional benefit in improved gait compared with exercise alone . A larger study is indicated to determine if weight loss provides additional benefits to exercise alone in this patient population
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 .