title: Epidemiology of sarcopenia among the elderly in New Mexico. Muscle size and strength are increased following walk training with restricted venous blood flow from the leg muscle, Kaatsu-walk training. Low-Load High Volume Resistance Exercise Stimulates Muscle Protein Synthesis More Than High-Load Low Volume Resistance Exercise in Young Men Home-based resistance training: predictors of participation and adherence. Physical activity and leg strength predict decline in mobility performance in older persons. Resistance exercise load does not determine training-mediated hypertrophic gains in young men. The effects of multidimensional home-based exercise on functional performance in elderly people. Association of muscle power with functional status in community-dwelling elderly women. Effects on balance, falls, and bone mineral density of a home-based exercise program without home visits in community-dwelling elderly women: a randomized controlled trial. The effects of elastic band resistance training combined with blood flow restriction on strength, total bone‐free lean body mass and muscle thickness in postmenopausal women Effects of Low‐Intensity Walk Training With Restricted Leg Blood Flow on Muscle Strength and Aerobic Capacity in Older Adults Effect of exercise on extraskeletal risk factors for hip fractures in elderly women with low BMD: a population-based randomized controlled trial. The effects of physical therapists' guidance on improvement in a strength-training program for the frail elderly. Exercise--it's never too late: the strong-for-life program. A home-based exercise program for nondisabled older adults. Randomized controlled trial of exercise intervention for the prevention of falls in community-dwelling elderly Japanese women
abstract: Muscle mass decreases with age , leading to " sarcopenia , " or low relative muscle mass , in elderly people . Sarcopenia is believed to be associated with metabolic , physiologic , and functional impairments and disability . Methods of estimating the prevalence of sarcopenia and its associated risks in elderly population s are lacking . Data from a  population -based survey of 883 elderly Hispanic and non-Hispanic white men and women living in New Mexico ( the New Mexico Elder Health Survey , 1993 - 1995 ) were analyzed to develop a method for estimating the prevalence of sarcopenia . An anthropometric equation for predicting appendicular skeletal muscle mass was developed from a r and om sub sample ( n = 199 ) of participants and was extended to the total sample . Sarcopenia was defined as appendicular skeletal muscle mass (kg)/height2 ( m2 ) being less than two st and ard deviations below the mean of a young reference group . Prevalences increased from 13 - 24 % in persons under 70 years of age to > 50 % in persons over 80 years of age , and were slightly greater in Hispanics than in non-Hispanic whites . Sarcopenia was significantly associated with self-reported physical disability in both men and women , independent of ethnicity , age , morbidity , obesity , income , and health behaviors . This study provides some of the first estimates of the extent of the public health problem posed by sarcopenia Previous studies have shown that low-intensity resistance training with restricted muscular venous blood flow ( Kaatsu ) causes muscle hypertrophy and strength gain . To investigate the effects of daily physical activity combined with Kaatsu , we examined the acute and chronic effects of walk training with and without Kaatsu on MRI-measured muscle size and maximum dynamic ( one repetition maximum ) and isometric strength , along with blood hormonal parameters . Nine men performed Kaatsu-walk training , and nine men performed walk training alone ( control-walk ) . Training was conducted two times a day , 6 days/wk , for 3 wk using five sets of 2-min bouts ( treadmill speed at 50 m/min ) , with a 1-min rest between bouts .  Mean oxygen uptake during Kaatsu-walk and control-walk exercise was 19.5 ( SD 3.6 ) and 17.2 % ( SD 3.1 ) of treadmill-determined maximum oxygen uptake , respectively . Serum growth hormone was elevated ( P < 0.01 ) after acute Kaatsu-walk exercise but not in control-walk exercise .  MRI-measured thigh muscle cross-sectional area and muscle volume increased by 4 - 7 % , and one repetition maximum and maximum isometric strength increased by 8 - 10 % in the Kaatsu-walk group . There was no change in muscle size and dynamic and isometric strength in the control-walk group . Indicators of muscle damage ( creatine kinase and myoglobin ) and resting anabolic hormones did not change in both groups . The results suggest that the combination of leg muscle blood flow restriction with slow-walk training induces muscle hypertrophy and strength gain , despite the minimal level of exercise intensity . Kaatsu-walk training may be a potentially useful method for promoting muscle hypertrophy , covering a wide range of the population , including the frail and elderly Background We aim ed to determine the effect of resistance exercise intensity ( % 1 repetition maximum—1RM ) and volume on muscle protein synthesis , anabolic signaling , and myogenic gene expression . Methodology /Principal Findings Fifteen men ( 21±1 years ; BMI = 24.1±0.8 kg/m2 ) performed 4 sets of unilateral leg extension exercise at different exercise loads and /or volumes : 90 % of repetition maximum ( 1RM ) until volitional failure ( 90FAIL ) , 30 % 1RM work-matched to 90%FAIL ( 30WM ) , or 30 % 1RM performed until volitional failure ( 30FAIL ) . Infusion of [ ring-13C6 ] phenylalanine with biopsies was used to measure rates of mixed ( MIX ) , myofibrillar ( MYO ) , and sarcoplasmic ( SARC ) protein synthesis at rest , and 4 h and 24 h after exercise . Exercise at 30WM induced a significant increase above rest in MIX ( 121 % ) and MYO ( 87 % ) protein synthesis at 4 h post-exercise and but at 24 h in the MIX only . The increase in the rate of protein synthesis in MIX and MYO at 4 h post-exercise with 90FAIL and 30FAIL was greater than 30WM , with no difference between these conditions ; however , MYO remained elevated ( 199 % ) above rest at 24 h only in 30FAIL . There was a significant increase in AktSer473 at 24h in all conditions ( P = 0.023 ) and mTORSer2448 phosphorylation at 4 h post-exercise ( P = 0.025 ) . Phosporylation of Erk1/2Tyr202/204 , p70S6KThr389 , and 4E-BP1Thr37/46 increased significantly ( P<0.05 ) only in the 30FAIL condition at 4 h post-exercise , whereas , 4E-BP1Thr37/46 phosphorylation was greater 24 h after exercise than at rest in both 90FAIL ( 237 % ) and 30FAIL ( 312 % ) conditions . Pax7 mRNA expression increased at 24 h post-exercise ( P = 0.02 ) regardless of condition . The mRNA expression of MyoD and myogenin were consistently elevated in the 30FAIL condition . Conclusions / Significance These results suggest that low-load high volume resistance exercise is more effective in inducing acute muscle anabolism than high-load low volume or work matched resistance exercise modes This study identified factors associated with exercise participation  and  adherence  in a sample of 102 sedentary , functionally limited , community-dwelling adults aged 60 to 94 years who participated in a home-based resistance training program .  Stepwise regression analyses revealed that baseline physical factors ( i.e. , higher levels of mobility , weaker muscle strength , and fewer numbers of new medical conditions ) were associated with higher rates of participation in the home program .  Positive attitudes and a sense of control toward exercise , lower levels of confusion and depressive moods , and the development of fewer new medical problems during the program were related to higher levels of adherence to the program . Findings revealed that although physical health variables were the primary indicators of an older person 's overall participation in the program , it was the psychological factors that were most important to adherence to this home-based program OBJECTIVES To assess the extent to which physical activity and leg strength are associated with change in mobility  in older persons . DESIGN Prospect i ve , observational cohort study . SETTING Retirement communities across the Chicago metropolitan area participating in the Rush Memory and Aging Project . PARTICIPANTS Eight hundred eighty-six ambulatory older persons without dementia . MEASUREMENT Rate of change in mobility . RESULTS In a linear mixed-effects model that controlled for age , sex , education , and a term for baseline physical activity , a higher level of physical activity was associated with a slower rate of mobility decline ( estimate=0.006 , st and ard error (SE)=0.003 , P=.03 ) ; each additional hour of physical activity at baseline was associated with an approximately 3 % decrease in the rate of mobility decline . In a similar model , a higher level of baseline leg strength was associated with a slower rate of mobility decline ( estimate=0.031 , SE=0.132 , P=.02 ) ; each additional unit of leg strength at baseline was associated with an approximately 20 % decrease in the rate of mobility decline . In a final model , which included terms for physical activity and leg strength together , both were associated with decline in mobility . Furthermore , both remained associated with mobility even after controlling for body composition , balance , pulmonary function , cognition , history of joint pain , cardiovascular diseases and risk factors , and medications . CONCLUSION Physical activity and leg strength are relatively independent predictors of mobility decline  in older persons . Although physical activity may improve strength , the beneficial effect of physical activity on mobility is likely to involve other pathways We have reported that the acute postexercise increases in muscle protein synthesis rates , with differing nutritional support , are predictive of longer-term training-induced muscle hypertrophy . Here , we aim ed to test whether the same was true with acute exercise-mediated changes in muscle protein synthesis . Eighteen men ( 21 ± 1 yr , 22.6 ± 2.1 kg/m(2 ) ; means ± SE ) had their legs r and omly assigned to two of three training conditions that differed in contraction intensity [ % of maximal strength ( 1 repetition maximum ) ] or contraction volume ( 1 or 3 sets of repetitions ) : 30%-3 , 80%-1 , and 80%-3 . Subjects trained each leg with their assigned regime for a period of 10 wk , 3 times/wk . We made pre- and posttraining measures of strength , muscle volume by magnetic resonance ( MR ) scans , as well as pre- and posttraining biopsies of the vastus lateralis , and a single postexercise ( 1 h ) biopsy following the first bout of exercise , to measure signaling proteins . Training-induced increases in MR-measured muscle volume were significant ( P < 0.01 ) , with no difference between groups : 30%-3 = 6.8 ± 1.8 % , 80%-1 = 3.2 ± 0.8 % , and 80%-3= 7.2 ± 1.9 % , P = 0.18 . Isotonic maximal strength gains were not different between 80%-1 and 80%-3 , but were greater than 30%-3 ( P = 0.04 ) , whereas training-induced isometric strength gains were significant but not different between conditions ( P = 0.92 ) . Biopsies taken 1 h following the initial resistance exercise bout showed increased phosphorylation ( P < 0.05 ) of p70S6 K only in the 80%-1 and 80%-3 conditions . There was no correlation between phosphorylation of any signaling protein and hypertrophy . In accordance with our previous acute measurements of muscle protein synthetic rates a lower load lifted to failure result ed in similar hypertrophy as a heavy load lifted to failure BACKGROUND This study tested the hypothesis that a home-based exercise program would improve functional performance in elderly people . METHODS We conducted a 6-month , single-blinded , r and omized controlled trial . 72 community dwelling men and women ( aged > /=70 years ) with self-reported and laboratory-based functional impairment were recruited for the study . Participants were r and omly assigned to either a home-based progressive strength , balance , and general physical activity intervention or an attention-control group that received home-based nutrition education .  Functional performance was measured in the laboratory using the Physical Performance Test ( PPT ) and the Established Population s for Epidemiologic Studies of the Elderly ( EPESE ) short physical performance battery . Physiologic capacity was measured by strength ( one repetition maximum ) , dynamic balance ( t and em walk ) , gait speed ( 2-meter walk ) , and cardiovascular endurance ( 6-minute walk ) . RESULTS 70 participants ( 97 % ) completed the 6-month trial . Compliance with study interventions within each group ranged from 75 % in controls to 82 % in exercisers . PPT increased by 6.1 + /- 13.4 % in exercisers and decreased by 2.8 + /- 13.6 % in controls ( p = .02 ) . EPESE improved by 26.2 + /- 37.5 % in exercisers and decreased by 1.2 + /- 22.1 % in controls ( p = .001 ) . Dynamic balance improved by 33.8 + /- 14.4 % in exercisers versus 11.5 + /- 23.7 % in controls ( p = .0002 ) . There were no differences between groups in the change in strength , gait speed , or cardiovascular endurance . CONCLUSIONS Minimally supervised exercise is safe and can improve functional performance  in elderly individuals . The improvements in functional performance occurred along with improvements in balance but without a significant change in muscle strength or endurance BACKGROUND Identification of the physiologic factors most relevant to functional independence in the elderly population is critical for the design of effective interventions . It has been suggested that muscle power may be more directly related to impaired physical performance than muscle strength in elderly persons . We tested the hypothesis that peak muscle power is closely associated with self-reported functional status in sedentary elderly community-dwelling women . METHODS We used baseline data that were collected as part of a 1-year r and omized controlled clinical trial of a combined program of strength , power , and endurance training in 80 elderly women ( mean age 74.8 + /- 5.0 years ) with 3.2 + /- 1.9 chronic diseases , selected for baseline functional impairment and /or falls . RESULTS Functional status at baseline was related in univariate analyses to physiologic capacity , habitual physical activity level , neuropsychological status , and medical diagnoses . Leg power had the strongest univariate correlation to self-reported functional status ( r = -.47 , p < .0001 ) of any of the physiologic factors we tested . In a forward stepwise regression model , leg press power and habitual physical activity level were the only two factors that contributed independently to functional status ( r = .64 , p < .0001 ) , accounting for 40 % of the variance in functional status . CONCLUSIONS Leg power is a strong predictor of self-reported functional status in elderly women The aim of the present study was to investigate the effects of home-based exercise without home visits on physical function , falls , and bone mineral density in community-dwelling elderly women . Sixty community-dwelling , elderly ( > or = 65 years of age ) women were recruited from a Japanese community . Subjects were r and omly assigned to a home-based exercise group or a control group . The subjects assigned to the home-based exercise group performed home-based exercise without home visits 3 times per week for 6 months in their homes . Assessment s of physical function and bone mineral density were carried out before and after intervention in both groups . Muscle strength , gait velocity , the timed up and go test ( TUGT ) , single leg stance time , the bend reach performance test , and reaction time were measured to assess physical function . The patients ' history of falls was also assessed before and after the 12-month follow-up . To determine bone mineral density , the speed of sound ( SOS ) at the right calcaneus was measured using a quantitative ultrasound device . There were no significant differences between the two groups in baseline characteristics . 82.6 % of subjects completed the prescribed exercise program in the home-based exercise group . Compared to the control group , TUGT improved significantly ( p<0.05 ) in the home-based exercise group . Home-based exercise without home visits can be adopted for community-dwelling elderly women , particularly since no specific place or instructor is needed Elastic b and ( EB ) training is a common form of resistance training used by the elderly , individuals with joint problems or those recovering from injury .  EB training performed at low intensities by these population s may have little effect on muscle hypertrophy . However , when combined with blood flow restriction ( BFR ) , low‐intensity EB resistance training may result in muscle hypertrophy Purpose Slow-walk training combined with restricted leg muscular blood flow ( KAATSU ) produces muscle hypertrophy and strength gains in young men , which may lead to increased aerobic capacity and functional fitness . The purpose of this study was to investigate the effects of walk training combined with KAATSU on muscle size , strength , and functional ability , as well as aerobic capacity , in older participants . Methods A total of 19 active men and women , aged 60 to 78 years , were r and omized into either a KAATSU-walk training group ( n = 11 , K-walk ) or a nonexercising control group ( n = 8 , control ) . The K-walk group performed 20-minute treadmill walking ( 67 m/min ) , 5 days/wk for 6 weeks . Results Isometric ( 11 % ) and isokinetic ( 7%-16 % ) knee extension and flexion torques , muscle-bone cross-sectional area ( 5.8 % and 5.1 % for thigh and lower leg , respectively ) , as well as ultrasound-estimated skeletal muscle mass ( 6.0 % and 10.7 % for total and thigh , respectively ) increased ( P < .05 ) in the K-walk group but not in the control group . Functional ability also increased significantly only in the K-walk group ( P < .05 ) ; however , there was no change in the estimated peak oxygen uptake(absolute and relative to body mass ) for either group . Conclusion The results of the current study indicate that 6 weeks of KAATSU-walk training did not simultaneously improve cardiovascular and muscular fitness  of older participants . However , it significantly increased muscular size and strength as well as functional ability of active older men and women UNLABELLED We conducted a 30-month population -based , r and omized , controlled trial in 160 elderly women at risk for fractures on the basis of a low baseline BMD . Mainly home-based weight-bearing exercise was effective in improving strength , balance , and gait . INTRODUCTION Evidence on the effect of exercise on extraskeletal risk factors for hip fractures comes mainly from studies in voluntary low-risk women , and no population -based , long-term interventions have been performed in elderly women with low bone mass . The aim of this study was to determine the effect of long-term weight-bearing exercise on balance , muscle strength , and gait in elderly women at risk for fractures on the basis of a low baseline BMD . MATERIAL S AND METHODS A birth cohort of 1690 women 70 - 73 years of age were invited to the radius and hip BMD measurements ; 96 women were excluded because of medical reasons ; 160 women with radius and hip BMD values of > 2 SD below the reference value were included in the trial . The participants were r and omly assigned to 30 months of impact , balancing , and strengthening exercises or to no intervention . Main outcome measures were body sway length and leg strength at month 30 . Secondary endpoints included gait speed , endurance , and grip strength . Outcomes were assessed at 0 , 12 , 24 , and 30 months using blinded operators . Repeated- measures ANOVA was used to determine statistical significance . The analyses were performed on an intention-to-treat basis . RESULTS Body sway increased more in the control group than in the exercise group over time ( time-group interaction , p < 0.001 ) . Leg strength improved in the exercise group and decreased in the control group ( interaction , p < 0.001 ) . A significant time-group interaction ( p < 0.001 ) in favor of the exercise group was found on the following secondary endpoints : the timed up and go test score , walking speed , and distance walked in 2 minutes . CONCLUSIONS Weight-bearing exercise is an effective way of modifying extraskeletal risk factors for fractures in elderly women Elderly participants experiencing difficulty in chair rising and with a maximum knee-extensor torque below 87.5 N . m were r and omized  to different versions of a strength-training program for the knee-extensors : to a high-guidance group ( HG ; two group sessions supervised by a physical therapist and one unsupervised home session per week , n = 17 ) , a medium-guidance group ( MG ; one supervised group session and two unsupervised home sessions per week , n = 16 ) , or a control group ( C ; no exercise , n = 16 ) . Maximal isometric knee strength increased more in HG than in C ( p = .03 ) and with increasing guidance ( p = .03 ) . The effect was mainly the result of participants with low initial strength . Walking speed increased more for HG than for C ( p = .02 ) and than for MG ( p = .06 ) . No statistically significant improvements were seen on other functional tests . In summary , the study shows a trend toward better results with more supervision , but more and larger studies are needed to confirm this OBJECTIVES This investigation determined whether an in-home resistance training program achieved health benefits in older adults with disabilities . METHODS A r and omized controlled trial compared the effects of assigning 215 older persons to either a home-based resistance exercise training group or a waiting list control group . Assessment s were conducted at baseline and at 3 and 6 months following r and omization . The program consisted of videotaped exercise routines performed with elastic b and s of varying thickness . RESULTS High rates of exercise adherence were achieved , with 89 % of the recommended exercise sessions performed over 6 months . Relative to controls , subjects who participated in the program achieved statistically significant lower extremity strength improvements of 6 % to 12 % , a 20 % improvement in t and em gait , and a 15 % to 18 % reduction in physical and overall disability at the 6-month follow-up . No adverse health effects were encountered . CONCLUSIONS These findings provide important evidence that home-based resistance exercise programs design ed for older persons with disabilities hold promise as an effective public health strategy OBJECTIVES This paper describes a videotaped , home-based , strength training program , titled Strong-for-Life and reports on its effectiveness in improving muscle strength , psychological well-being , and health status in a sample of older persons . DESIGN AND SETTING We enrolled 102 nondisabled , community-dwelling older people aged 66 to 87 , identified from the Medicare beneficiary list , into a r and omized , controlled trial . MEASUREMENTS Effectiveness was based on change in isokinetic upper and lower extremity muscle strength , psychologic well-being , and health status . RESULTS Results revealed several statistically significant short-term benefits after 12 to 15 weeks of exercise , especially for men . Younger older adults demonstrated a 10 % improvement in knee extensor strength relative to control subjects . Older male exercisers achieved significant differences relative to controls in perceived anger , tension , and overall social functioning . Male exercisers , in general , achieved significant improvement in perceived vigor . Women did not report psychological benefits following participation in the program . CONCLUSION Study results reveal that the Strong for Life program , design ed to be widely disseminated to the nondisabled older population , has many short-term positive benefits Falls are common in elderly people . Possible consequences include serious injuries and the post-fall syndrome , with functional decline and limitation of physical activity . The present r and omized controlled study sought to clarify the benefits of a combined long-term and home-based fall prevention program for elderly Japanese women . The subjects were individuals aged over 73 years , living at home in a western suburb of Tokyo , who had attended a comprehensive geriatric health check . Persons with a marked decline in the basic activities of daily living ( ADL ) , hemiplegia , or those missing baseline data were excluded . Fifty-two subjects who expressed a wish to participate in the trial were r and omized , 28 to an exercise-intervention group and 24 to a control group .  Baseline data for age , h and grip force , walking speed , total serum cholesterol , serum albumin , basic ADL , visual and auditory impairments , self-rated health , and experience of falls did not differ significantly between the two groups . Beginning from June 2000 , the intervention group attended a 6-month program of fall-prevention exercise classes aim ed at improving leg strength , balance , and walking ability ;  this was supplemented by a home-based exercise program that focused on leg strength . The control group received only a pamphlet and advice on fall prevention . The average rate of attendance at exercise class was 75.3 % ( range , 64 % to 86 % ) . Participants showed significant improvements in t and em walk and functional reach after the intervention program , with enhanced self confidence . At the 8-month follow-up , the proportion of women with falls was 13.6 % ( 3/22 ) in the intervention group and 40.9 % ( 9/22 ) in the control group . At 20 months , the proportion remained unchanged , at 13.6 % in the intervention group , but had increased to 54.5 % ( 12/22 ) in the control group , which showed a statistically significant difference between the two groups ( Fisher ’s exact test ; P = 0.0097 ) . The total number of falls during the 20-month follow-up period was 6 in the intervention group and 17 in the control group . We conclude that a moderate exercise intervention program plus a home-based program significantly decreases the incidence of falls in both the short and the long term , contributing to improved health and quality of life in the elderly
target: Overall , home-based resistance exercise  can improve both strength and functional ability , but the improvements are generally small .
  The intensity of the exercises might not progress sufficiently enough to produce large improvements in strength as a result of less supervision or a lack of motivation to increase the intensity further
background: Home-based resistance exercise is commonly used for individuals who might not have access or the ability to use traditional resistance exercise .
  However , the extent to which home-based resistance exercise can improve both strength and functional ability has not been investigated in healthy older individuals using a systematic analysis .