human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To test the efficacy of high-velocity training in healthy older persons . DESIGN A 12-week r and omized trial , with subjects blocked for gender and residence , comparing high-velocity resistance training with a self-paced walking program . SETTING Retirement community . PARTICIPANTS Forty-three volunteers over the age of 70 years . INTERVENTION Power group : high-velocity leg exercises 3 times weekly with weekly increases in resistance combined with 45 minutes of moderate , nonresistance exercise weekly . Walking group : moderate intensity exercise 30 minutes daily , 6 days weekly . MAIN OUTCOME MEASURES Variables measured included leg press peak power and leg extensor strength . Functional performance outcomes included : 6-minute walk distance , Short Physical Performance Battery , Physical Performance Test , and Medical Outcomes Study Short-Form Health Survey . RESULTS Peak power improved 22 % ( p = .004 ) in the power group ( 3.7 + /- 1.0 W/kg to 4.5 + /- 1.4 W/kg ) but did not change in the walking group ( 3.99 + /-.76 W/kg to 3.65 + /-.94 W/kg ) . Leg extensor power at resistance of 50 % , 60 % , and 70 % of body weight increased 50 % , 77 % , and 141 % , respectively , in the power group ( p < .0001 , repeated- measures analysis of variance ) . Strength improved 22 % in the power-trained individuals and 12 % in the walkers ( p < .0001 ) . Training did not improve functional task performance in either group . One subject developed a radiculopathy during training . CONCLUSIONS Resistance training focusing on speed of movement improved leg power and maximal strength substantially , but did not improve functional performance in healthy high-functioning older volunteers Changes in strength , speed and size of the quadriceps muscle have been investigated in elderly men and women after 6 months of isometric strength training . We have also indirectly investigated the role of metabolites as a stimulus for muscle hypertrophy by study ing two training protocol s. One thigh was trained using short , intermittent contractions ( IC ) , while the other trained using long , continuous contractions ( CC ) . This meant that there should be a greater metabolite change in the muscle performing CC , as the blood flow is occluded for longer . Nine subjects [ eight women , mean ( SE ) age , 71.8 ( 2.9 ) years ] were measured for contractile properties and strength before and after training , and compared to nine age-matched controls [ 71.5 ( 2.1 ) years ] . The training group increased quadriceps strength by 48.7 (9.1)% ( P < 0.005 ) and 53.1 ( 11.3 ) % ( P < 0.005 ) following the IC and CC protocol s , respectively . There was no change in muscle strength in the controls . Both muscles showed significant slowing after training as measured by the relaxation times and the force-frequency ratio . There were non-significant decreases in muscle fatigability after training . The control group also showed some significant decreases in fatigability and muscle speed . The training group showed significant increases in muscle ( and bone ) cross-sectional area of 4.0 (1.7)% and 4.9 (1.3)% following the CC and IC protocol s , respectively . These increases were significantly different from the decrease observed in the control group . These findings suggest that people over the age of 55 still have the capacity to increase muscle strength and size , and that the training causes slowing of the muscle . Muscle hypertrophy does not seem to be strongly influenced by metabolite changes in this age group , as there were no differences in measurements observed between protocol OBJECTIVE To use two different exercise programs over a 2-year period to reduce falls and their sequelae among residents of two long-term care facilities . DESIGN R and omized , controlled trial . SETTING The study took place at two long-term care facilities with services ranging from independent living to skilled nursing . PARTICIPANTS One hundred and ten participants whose average age was 84 and who were capable of ambulating with or without assistive devices and could follow simple directions . INTERVENTION Participants were r and omized to one of two exercise groups ( resistance/endurance plus basic enhanced programming or tai chi plus basic enhanced programming ) or to a control group ( basic enhanced programming only ) . Exercise classes were held three times per week throughout the study . MEASUREMENTS Participants were evaluated for cognitive and physical functioning at baseline and 6 , 12 , and 24 months . Falls were determined from incident reports filed by the nursing staffs at the facilities . RESULTS Time to first fall , time to death , number of days hospitalized , and incidence of falls did not differ among the treatment and control groups ( P>.05 ) . Among all participants , those who fell had significantly lower baseline Folstein Mini-Mental State Examination and instrumental activities of daily living scores and experienced significantly greater declines in these measures over the 2-year program . CONCLUSION There were no significant differences in falls among the two exercise groups and the control group . Lack of treatment differences and low adherence rates suggest that residents of long-term care facilities may require individualized exercise interventions that can be adapted to their changing needs OBJECTIVE To determine the effect of frequency of resistive training on gain in muscle strength and neuromuscular performance in healthy older adults . DESIGN A r and omized controlled trial with subjects assigned either to high-intensity resistance training 1 ( EX1 ) , 2 ( EX2 ) , or 3 ( EX3 ) days per week for 24 weeks or to a control group ( CO ) . SETTING An exercise facility at an academic medical center . SUBJECTS Forty-six community-dwelling healthy men ( n = 29 ) and women ( n = 17 ) aged 65 to 79 years . INTERVENTION Progressive resistance training consisting of three sets of eight exercises targeting major muscle groups of the upper and lower body , at 80 % of one-repetition maximum ( 1-RM ) for eight repetitions , either 1 , 2 , or 3 days per week . MEASURES Dynamic muscle strength ( 1-RM ) using isotonic equipment every 4 weeks , bone mineral density and body composition by dual energy X-ray absorptiometry ( DXA ) , and neuromuscular performance by timed chair rise and 6-meter backward t and em walk . RESULTS For each of the eight exercises , muscle strength increased in the exercise groups relative to CO ( P < .01 ) , with no difference among EX1 , EX2 and EX3 groups at any measurement interval . Percent change averaged 3.9 + /- 2.4 ( CO ) , 37.0 + /- 15.2 ( EX1 ) , 41.9 + /- 18.2 ( EX2 ) , and 39.7 + /- 9.8 ( EX3 ) . The time to rise successfully from the chair 5 times decreased significantly ( P < .01 ) at 24 weeks , whereas improvement in the 6-meter backward t and em walk approached significance ( P = .10 ) in the three exercise groups compared with CO . Changes in chair rise ability were correlated to percent changes in quadriceps strength ( r = -0.40 , P < .01 ) and lean mass ( r = -0.40 , P < .01 ) . CONCLUSIONS A program of once or twice weekly resistance exercise achieves muscle strength gains similar to 3 days per week training in older adults and is associated with improved neuromuscular performance . Such improvement could potentially reduce the risk of falls and fracture in older adults BACKGROUND In patients with intermittent claudication , a supervised walking exercise program increases peak exercise performance and community-based functional status .  Patients with peripheral arterial disease also have muscle weakness in the affected extremity that may contribute to the walking impairment . However , the potential benefits of training modalities other than walking exercise , such as strength training , have not been critically evaluated in this patient population . The present study tested the hypothesis that a strength training program would be as effective as treadmill walking exercise and that combinations of strengthening and walking exercise would be more effective than either alone in improving exercise performance . METHODS AND RESULTS Twenty-nine patients with disabling claudication were r and omized to 12 weeks of supervised walking exercise on a treadmill ( 3 h/wk at a work intensity sufficient to produce claudication ) , strength training ( 3 h/wk of resistive training of five muscle groups of each leg ) , or a nonexercising control group . Grade d treadmill testing was performed to maximally tolerated claudication pain to define changes in peak exercise performance . After 12 weeks , patients in the treadmill training program had a 74 + /- 58 % increase in peak walking time as well as improvements in peak oxygen consumption ( VO2 ) and the onset of claudication pain . Patients in the strength-trained group had a 36 + /- 48 % increase in peak walking time but no change in peak VO2 or claudication onset time . Control subjects had no changes in any of these measures over the 12-week period . After the first 12 weeks , patients in the initial walking exercise group continued for 12 more weeks of supervised treadmill training . This result ed in an additional 49 + /- 53 % increase in peak walking time ( total of 128 + /- 99 % increase over the 24 weeks ) . After the initial 12 weeks , patients in the strength-trained group began 12 weeks of supervised treadmill training , and patients in the control group participated in a 12-week combined program of strengthening and treadmill walking exercise . The combined strength and treadmill training program and treadmill training after 12 weeks of strength training result ed in increases in peak exercise performance similar to those observed with 12 weeks of treadmill training alone . CONCLUSIONS A supervised treadmill walking exercise program is an effective means to improve exercise performance in patients with intermittent claudication , with continued improvement over 24 weeks of training . In contrast , 12 weeks of strength training was less effective than 12 weeks of supervised treadmill walking exercise . Finally , strength training , whether sequential or concomitant , did not augment the response to a walking exercise program OBJECTIVE We evaluated the effects of exercise on neurobehavioral function in healthy older people more than 75 years of age . DESIGN A r and omized controlled trial with 6-month follow-up was conducted . SETTING The study was performed in the rural town of Kahoku , Japan , the population of which is considered representative of the older population of Japan . PARTICIPANTS We studied 42 healthy volunteers ( 18 men and 24 women ; mean age , 79 years ( range 75 to 87 years ) ) who were r and omly assigned to one of two groups , exercise or control . INTERVENTION Subjects assigned to the exercise group were instructed to exercise for 60 minutes twice a week for 6 months . Subjects in the control group were not instructed to engage in an specific exercise regimen . MEASUREMENTS The following measurements were recorded for both groups at baseline and at 6-month follow-up : ( 1 ) Neurobehavioral function as determined by the following tests : Mini-Mental State Exam ( MMSE ) , Hasegawa Dementia Scale Revised ( HDSR ) , Visuospatial Cognitive Performance Test ( VCP-test ) , Button score , Up & Go test , and Functional Reach ; and ( 2 ) Body mass index and blood pressure . RESULTS The effects of exercise were shown in the Up & Go test , and Functional Reach ( ANOVA with repeated measures ) . CONCLUSION This study demonstrates the acceptability and effectiveness of exercise on neurobehavioral function , even in older people more than 75 years of age OBJECTIVES This r and omized controlled trial studied the effects of a low- to moderate-intensity group exercise program on strength , endurance , mobility , and fall rates in fall-prone elderly men with chronic impairments . METHODS Fifty-nine community-living men ( mean age = 74 years ) with specific fall risk factors ( i.e. , leg weakness , impaired gait or balance , previous falls ) were r and omly assigned to a control group ( n = 28 ) or to a 12-week group exercise program ( n = 31 ) . Exercise sessions ( 90 minutes , three times per week ) focused on increasing strength and endurance and improving mobility and balance . Outcome measures included isokinetic strength and endurance , five physical performance measures , and self-reported physical functioning , health perception , activity level , and falls . RESULTS Exercisers showed significant improvement in measures of endurance and gait . Isokinetic endurance increased 21 % for right knee flexion and 26 % for extension . Exercisers had a 10 % increase ( p < .05 ) in distance walked in six minutes , and improved ( p < .05 ) scores on an observational gait scale . Isokinetic strength improved only for right knee flexion . Exercise achieved no significant effect on hip or ankle strength , balance , self-reported physical functioning , or number of falls . Activity level increased within the exercise group . When fall rates were adjusted for activity level , the exercisers had a lower 3-month fall rate than controls ( 6 falls/1000 hours of activity vs 16.2 falls/1000 hours , p < .05 ) . DISCUSSION These findings suggest that exercise can improve endurance , strength , gait , and function in chronically impaired , fall-prone elderly persons . In addition , increased physical activity was associated with reduced fall rates when adjusted for level of activity OBJECTIVE To determine the effects of 12 weeks of progressive resistance strength training on the isometric strength , explosive power , and selected functional abilities of healthy women aged 75 and over . DESIGN Subjects were matched for age and habitual physical activity and then r and omly assigned into either a control or an exercise group . SETTING The Muscle Function Laboratory , Royal Free Hospital School of Medicine , London . PARTICIPANTS Fifty-two healthy women were recruited through local and national newspapers . Five dropped out before and seven (  
    Output:
    
agent
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
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To test the efficacy of high-velocity training in healthy older persons . DESIGN A 12-week r and omized trial , with subjects blocked for gender and residence , comparing high-velocity resistance training with a self-paced walking program . SETTING Retirement community . PARTICIPANTS Forty-three volunteers over the age of 70 years . INTERVENTION Power group : high-velocity leg exercises 3 times weekly with weekly increases in resistance combined with 45 minutes of moderate , nonresistance exercise weekly . Walking group : moderate intensity exercise 30 minutes daily , 6 days weekly . MAIN OUTCOME MEASURES Variables measured included leg press peak power and leg extensor strength . Functional performance outcomes included : 6-minute walk distance , Short Physical Performance Battery , Physical Performance Test , and Medical Outcomes Study Short-Form Health Survey . RESULTS Peak power improved 22 % ( p = .004 ) in the power group ( 3.7 + /- 1.0 W/kg to 4.5 + /- 1.4 W/kg ) but did not change in the walking group ( 3.99 + /-.76 W/kg to 3.65 + /-.94 W/kg ) . Leg extensor power at resistance of 50 % , 60 % , and 70 % of body weight increased 50 % , 77 % , and 141 % , respectively , in the power group ( p < .0001 , repeated- measures analysis of variance ) . Strength improved 22 % in the power-trained individuals and 12 % in the walkers ( p < .0001 ) . Training did not improve functional task performance in either group . One subject developed a radiculopathy during training . CONCLUSIONS Resistance training focusing on speed of movement improved leg power and maximal strength substantially , but did not improve functional performance in healthy high-functioning older volunteers Changes in strength , speed and size of the quadriceps muscle have been investigated in elderly men and women after 6 months of isometric strength training . We have also indirectly investigated the role of metabolites as a stimulus for muscle hypertrophy by study ing two training protocol s. One thigh was trained using short , intermittent contractions ( IC ) , while the other trained using long , continuous contractions ( CC ) . This meant that there should be a greater metabolite change in the muscle performing CC , as the blood flow is occluded for longer . Nine subjects [ eight women , mean ( SE ) age , 71.8 ( 2.9 ) years ] were measured for contractile properties and strength before and after training , and compared to nine age-matched controls [ 71.5 ( 2.1 ) years ] . The training group increased quadriceps strength by 48.7 (9.1)% ( P < 0.005 ) and 53.1 ( 11.3 ) % ( P < 0.005 ) following the IC and CC protocol s , respectively . There was no change in muscle strength in the controls . Both muscles showed significant slowing after training as measured by the relaxation times and the force-frequency ratio . There were non-significant decreases in muscle fatigability after training . The control group also showed some significant decreases in fatigability and muscle speed . The training group showed significant increases in muscle ( and bone ) cross-sectional area of 4.0 (1.7)% and 4.9 (1.3)% following the CC and IC protocol s , respectively . These increases were significantly different from the decrease observed in the control group . These findings suggest that people over the age of 55 still have the capacity to increase muscle strength and size , and that the training causes slowing of the muscle . Muscle hypertrophy does not seem to be strongly influenced by metabolite changes in this age group , as there were no differences in measurements observed between protocol OBJECTIVE To use two different exercise programs over a 2-year period to reduce falls and their sequelae among residents of two long-term care facilities . DESIGN R and omized , controlled trial . SETTING The study took place at two long-term care facilities with services ranging from independent living to skilled nursing . PARTICIPANTS One hundred and ten participants whose average age was 84 and who were capable of ambulating with or without assistive devices and could follow simple directions . INTERVENTION Participants were r and omized to one of two exercise groups ( resistance/endurance plus basic enhanced programming or tai chi plus basic enhanced programming ) or to a control group ( basic enhanced programming only ) . Exercise classes were held three times per week throughout the study . MEASUREMENTS Participants were evaluated for cognitive and physical functioning at baseline and 6 , 12 , and 24 months . Falls were determined from incident reports filed by the nursing staffs at the facilities . RESULTS Time to first fall , time to death , number of days hospitalized , and incidence of falls did not differ among the treatment and control groups ( P>.05 ) . Among all participants , those who fell had significantly lower baseline Folstein Mini-Mental State Examination and instrumental activities of daily living scores and experienced significantly greater declines in these measures over the 2-year program . CONCLUSION There were no significant differences in falls among the two exercise groups and the control group . Lack of treatment differences and low adherence rates suggest that residents of long-term care facilities may require individualized exercise interventions that can be adapted to their changing needs OBJECTIVE To determine the effect of frequency of resistive training on gain in muscle strength and neuromuscular performance in healthy older adults . DESIGN A r and omized controlled trial with subjects assigned either to high-intensity resistance training 1 ( EX1 ) , 2 ( EX2 ) , or 3 ( EX3 ) days per week for 24 weeks or to a control group ( CO ) . SETTING An exercise facility at an academic medical center . SUBJECTS Forty-six community-dwelling healthy men ( n = 29 ) and women ( n = 17 ) aged 65 to 79 years . INTERVENTION Progressive resistance training consisting of three sets of eight exercises targeting major muscle groups of the upper and lower body , at 80 % of one-repetition maximum ( 1-RM ) for eight repetitions , either 1 , 2 , or 3 days per week . MEASURES Dynamic muscle strength ( 1-RM ) using isotonic equipment every 4 weeks , bone mineral density and body composition by dual energy X-ray absorptiometry ( DXA ) , and neuromuscular performance by timed chair rise and 6-meter backward t and em walk . RESULTS For each of the eight exercises , muscle strength increased in the exercise groups relative to CO ( P < .01 ) , with no difference among EX1 , EX2 and EX3 groups at any measurement interval . Percent change averaged 3.9 + /- 2.4 ( CO ) , 37.0 + /- 15.2 ( EX1 ) , 41.9 + /- 18.2 ( EX2 ) , and 39.7 + /- 9.8 ( EX3 ) . The time to rise successfully from the chair 5 times decreased significantly ( P < .01 ) at 24 weeks , whereas improvement in the 6-meter backward t and em walk approached significance ( P = .10 ) in the three exercise groups compared with CO . Changes in chair rise ability were correlated to percent changes in quadriceps strength ( r = -0.40 , P < .01 ) and lean mass ( r = -0.40 , P < .01 ) . CONCLUSIONS A program of once or twice weekly resistance exercise achieves muscle strength gains similar to 3 days per week training in older adults and is associated with improved neuromuscular performance . Such improvement could potentially reduce the risk of falls and fracture in older adults BACKGROUND In patients with intermittent claudication , a supervised walking exercise program increases peak exercise performance and community-based functional status .  Patients with peripheral arterial disease also have muscle weakness in the affected extremity that may contribute to the walking impairment . However , the potential benefits of training modalities other than walking exercise , such as strength training , have not been critically evaluated in this patient population . The present study tested the hypothesis that a strength training program would be as effective as treadmill walking exercise and that combinations of strengthening and walking exercise would be more effective than either alone in improving exercise performance . METHODS AND RESULTS Twenty-nine patients with disabling claudication were r and omized to 12 weeks of supervised walking exercise on a treadmill ( 3 h/wk at a work intensity sufficient to produce claudication ) , strength training ( 3 h/wk of resistive training of five muscle groups of each leg ) , or a nonexercising control group . Grade d treadmill testing was performed to maximally tolerated claudication pain to define changes in peak exercise performance . After 12 weeks , patients in the treadmill training program had a 74 + /- 58 % increase in peak walking time as well as improvements in peak oxygen consumption ( VO2 ) and the onset of claudication pain . Patients in the strength-trained group had a 36 + /- 48 % increase in peak walking time but no change in peak VO2 or claudication onset time . Control subjects had no changes in any of these measures over the 12-week period . After the first 12 weeks , patients in the initial walking exercise group continued for 12 more weeks of supervised treadmill training . This result ed in an additional 49 + /- 53 % increase in peak walking time ( total of 128 + /- 99 % increase over the 24 weeks ) . After the initial 12 weeks , patients in the strength-trained group began 12 weeks of supervised treadmill training , and patients in the control group participated in a 12-week combined program of strengthening and treadmill walking exercise . The combined strength and treadmill training program and treadmill training after 12 weeks of strength training result ed in increases in peak exercise performance similar to those observed with 12 weeks of treadmill training alone . CONCLUSIONS A supervised treadmill walking exercise program is an effective means to improve exercise performance in patients with intermittent claudication , with continued improvement over 24 weeks of training . In contrast , 12 weeks of strength training was less effective than 12 weeks of supervised treadmill walking exercise . Finally , strength training , whether sequential or concomitant , did not augment the response to a walking exercise program OBJECTIVE We evaluated the effects of exercise on neurobehavioral function in healthy older people more than 75 years of age . DESIGN A r and omized controlled trial with 6-month follow-up was conducted . SETTING The study was performed in the rural town of Kahoku , Japan , the population of which is considered representative of the older population of Japan . PARTICIPANTS We studied 42 healthy volunteers ( 18 men and 24 women ; mean age , 79 years ( range 75 to 87 years ) ) who were r and omly assigned to one of two groups , exercise or control . INTERVENTION Subjects assigned to the exercise group were instructed to exercise for 60 minutes twice a week for 6 months . Subjects in the control group were not instructed to engage in an specific exercise regimen . MEASUREMENTS The following measurements were recorded for both groups at baseline and at 6-month follow-up : ( 1 ) Neurobehavioral function as determined by the following tests : Mini-Mental State Exam ( MMSE ) , Hasegawa Dementia Scale Revised ( HDSR ) , Visuospatial Cognitive Performance Test ( VCP-test ) , Button score , Up & Go test , and Functional Reach ; and ( 2 ) Body mass index and blood pressure . RESULTS The effects of exercise were shown in the Up & Go test , and Functional Reach ( ANOVA with repeated measures ) . CONCLUSION This study demonstrates the acceptability and effectiveness of exercise on neurobehavioral function , even in older people more than 75 years of age OBJECTIVES This r and omized controlled trial studied the effects of a low- to moderate-intensity group exercise program on strength , endurance , mobility , and fall rates in fall-prone elderly men with chronic impairments . METHODS Fifty-nine community-living men ( mean age = 74 years ) with specific fall risk factors ( i.e. , leg weakness , impaired gait or balance , previous falls ) were r and omly assigned to a control group ( n = 28 ) or to a 12-week group exercise program ( n = 31 ) . Exercise sessions ( 90 minutes , three times per week ) focused on increasing strength and endurance and improving mobility and balance . Outcome measures included isokinetic strength and endurance , five physical performance measures , and self-reported physical functioning , health perception , activity level , and falls . RESULTS Exercisers showed significant improvement in measures of endurance and gait . Isokinetic endurance increased 21 % for right knee flexion and 26 % for extension . Exercisers had a 10 % increase ( p < .05 ) in distance walked in six minutes , and improved ( p < .05 ) scores on an observational gait scale . Isokinetic strength improved only for right knee flexion . Exercise achieved no significant effect on hip or ankle strength , balance , self-reported physical functioning , or number of falls . Activity level increased within the exercise group . When fall rates were adjusted for activity level , the exercisers had a lower 3-month fall rate than controls ( 6 falls/1000 hours of activity vs 16.2 falls/1000 hours , p < .05 ) . DISCUSSION These findings suggest that exercise can improve endurance , strength , gait , and function in chronically impaired , fall-prone elderly persons . In addition , increased physical activity was associated with reduced fall rates when adjusted for level of activity OBJECTIVE To determine the effects of 12 weeks of progressive resistance strength training on the isometric strength , explosive power , and selected functional abilities of healthy women aged 75 and over . DESIGN Subjects were matched for age and habitual physical activity and then r and omly assigned into either a control or an exercise group . SETTING The Muscle Function Laboratory , Royal Free Hospital School of Medicine , London . PARTICIPANTS Fifty-two healthy women were recruited through local and national newspapers . Five dropped out before and seven (  
    Output:
    