The value of strength training for older adults. Age differences in knee extension power, contractile velocity, and fatigability. The effect of lower limb muscle fatigue on obstacle negotiation during walking in older adults. The Effect of a Four-Week Balance Training Program on Anticipatory Postural Adjustments in Older Adults: A Pilot Feasibility Study. Ankle force and rate of force production increase following high intensity strength training in frail older adults Physical activity, muscle function, falls and fractures Effects of balance training on muscle coactivation during postural control in older adults: a randomized controlled trial. Efficacy of Nintendo Wii training on mechanical leg muscle function and postural balance in community-dwelling older adults: a randomized controlled trial. Effects of Aging on the Biomechanics of Slips and Falls Vitamin D supplementation improves neuromuscular function in older people who fall. Effect of high-intensity strength-training on functional measures of balance ability in balance-impaired older adults. Nutritional status, body composition, and quality of life in community-dwelling sarcopenic and non-sarcopenic older adults: A case-control study. Four-month course of soluble milk proteins interacts with exercise to improve muscle strength and delay fatigue in elderly participants. Supervised Balance Training and Wii Fit-Based Exercises Lower Falls Risk in Older Adults With Type 2 Diabetes. Effects of a targeted multimodal exercise program incorporating high-speed power training on falls and fracture risk factors in older adults: a community-based randomized controlled trial. Strength measures are better than muscle mass measures in predicting health-related outcomes in older people: time to abandon the term sarcopenia? Does a Single Session of High-Intensity Interval Training Provoke a Transient Elevated Risk of Falling in Seniors and Adults? The effect of resistance training on muscle strength and physical function in older, postmenopausal breast cancer survivors: a randomized controlled trial Hip protectors: a pilot study of older people in Taiwan. Can the control of bodily orientation be significantly improved in a group of older adults with a history of falls? Postural stability and quality of life after guided and self-training among older adults residing in an institutional setting Effect of intense strength training on standing balance, walking speed, and sit-to-stand performance in older adults. Sensory-Specific Balance Training in Older Adults: Effect on Proprioceptive Reintegration and Cognitive Demands
Health in older adults can best be measured in terms of functional status . Skeletal muscle strength has been reported to be a determinant of functional status in older individuals . Two major contributors to the decline in muscle function as a person ages are disuse and physical inactivity . Declining muscle function through a loss of muscular strength may decrease functional independence and mobility and increase the risk for falls and injuries , physical frailty , and disability .  Older individuals lacking an appropriate amount of muscular strength may not be able to perform various activities of daily living , which are important indicators of independence The purpose s of this study were to examine age and gender differences in knee extensor strength , power , and fatigue using open- and closed-chain testing procedures . We tested the hypothesis that specific strength ( strength/unit muscle mass ) would not differ by age , whereas age differences in specific power and fatigue would remain consequent to blunted maximal contractile velocity . Skeletal muscle performance was examined in 28 young ( 26.9 + /- 0.7 yr ) and 24 older ( 63.6 + /- 0.8 yr ) men and women . Assessment s included one-repetition maximum strength for knee extension , leg press , and squat ; concentric knee extensor peak power , velocity , and fatigability ; and  sit-to-st and power , fatigability , and relative neural activation ( electromyograph activity during sit-to-st and movement normalized to electromyograph activity during isometric maximum voluntary contraction ) . Thigh lean mass ( TLM ; kg ) was assessed by dual-energy X-ray absorptiometry . Specific strength ( N/kg TLM ) and specific power ( W/kg TLM ) were estimated by dividing absolute values by TLM . Age differences in specific strength were observed for knee extension only ( young , 41.2 + /- 1.0 N/kg TLM ; older , 32.4 + /- 1.0 N/kg TLM ; P < 0.05 ) . Adjustment for TLM did not negate age differences in knee extension specific power ( 25 - 41 % lower in older ; P < 0.05 ) across loads tested . Older adults experienced fatigue across 10 repetitions of knee extension as peak velocity fell by 24 % ( P < 0.05 ) . Deficits in concentric power persist after adjustment for TLM as maximum contractile velocity falls markedly with aging . Older adults are less capable of sustaining maximum concentric velocity during repetitive contractions . These findings suggest that velocity impairments are a possible contributor to mobility loss and falls risk among older adults . Interventions for improving contractile velocity should be pursued Tripping over obstacles is a common cause of falls in older adults , and muscle fatigue , which can alter walking patterns , may add to this risk . To date , no study has examined the effect of lower limb muscle fatigue on obstacle negotiation in older adults . 30 older adults ( 13 women , aged 78.3 [ 6.2 ] years )  negotiated a 12 m obstacle course , while completing a visual secondary task , under two r and omized conditions : rested or fatigued . For the fatigue condition , participants performed a repeated sit-to-st and movement , as fast as possible , until they could no longer continue . Participants then immediately began walking trials . Kinematic and kinetic data were collected on approach to , during , and after crossing a height-adjustable target obstacle ( 10 % and 20 % of leg length ) . Repeated measures ANOVA showed a statistically significant increase in lead limb vertical loading rate after stepping over the 10 % obstacle when fatigued , relative to rested ( P=0.046 ) . No other significant between-condition differences ( > 0.05 ) were observed for the other kinematic variables when negotiating the 10 % obstacle . Furthermore , no significant between-condition differences ( P>0.05 ) were observed for any kinetic or kinematic variables when negotiating the 20 % obstacle . This study describes a feasible method for investigating the consequences of lower limb muscle fatigue on obstacle crossing . The current finding of increased vertical loading rate when fatigued supports the need for further investigation into the effect of muscle fatigue on gait under different environmental conditions , fatiguing a range of muscles , analyzing a more comprehensive array of kinetic and kinematic measures , and in healthy and clinical population BACKGROUND Balance deterioration in older adults limits their activities of daily living , community participation , and is a significant risk factor for falls . One contributory element to this functional decline is impairment of anticipatory postural adjustments ( APAs ) . OBJECTIVES To evaluate the role and feasibility of a novel training program in improving APAs for balance control of older adults . METHOD Six older adults ( 73.3±5.0 years ) were r and omly assigned into the Experimental ( EG ) and Control groups ( CG ) . The EG participated in four weeks of APA-focused training involving catching a medicine ball while st and ing . All subjects were exposed to predictable external and self-initiated perturbations before and after training . EMG activity of eight trunk and leg muscles was recorded bilaterally and muscle onsets were analyzed during the anticipatory phase of postural control . Clinical tests of balance ( Timed-Up and Go , Single limb stance , and Activities-specific Balance Confidence scale ) were implemented . RESULTS Early onsets of APA activity prior to the external perturbations were seen in the EG following training . Moreover , early APA activity was observed in the EG prior to bilateral arm flexion , a task that was not a part of training , indicating a transfer of the learning effect of training . The improvement of APAs in the EG also result ed in improved performance on clinical outcome measures . There were no improvements seen in the CG for both the APA activity and the clinical balance tests . CONCLUSION The study outcome suggests that a four-week APA-based training program is feasible and could be effective in improving postural control , functional balance , mobility , and quality of life in older adults Background and aims : The most common cause of accidental injury and death in people over age 65 results from impacts associated with falling . Balance impaired older adults have poorer balance control than healthy young adults or healthy older adults . Lack of sufficient lower extremity strength and inability to rapidly produce muscle force may contribute to diminished balance control in the elderly . This study evaluated the effect of a 10-week high intensity strength- training program targeting key lower extremity muscles for the purpose of improving postural control in frail older adults . Methods : Thirteen experimental and fourteen control subjects , all balance impaired older adults were evaluated in response to unexpected platform perturbations that simulated slips . Results : Following strength training the experimental group was significantly stronger than the control group . Mean ankle moments improved in the experimental group following strength training during forward sway ( Right : p=0.067 , Left : p=0.009 ) and backward sway ( Right : p=0.031 , Left : p=0.058 ) . For the backward sway condition the ankle rate of torque production increased significantly in the experimental group ( Right : p=0.016 , Left : p=0.031 ) . Conclusions : Enhancement of lower extremity strength contributed to improvements in balance stability demonstrated by greater ankle force production , in response to balance threats Study design A thematic review . Objectives To evaluate if physical activity enhances muscle strength , improves balance , and reduces the fall frequency and the fracture incidence .  Background One of the major medical problems of today is the increasing incidence of fragility fractures .  Muscle strength and fall is one of the major determinants of a fracture . If physical activity could increase muscle strength , improve balance and reduce the fall frequency , then training could be recommended as prevention for fractures . Methods The review used Medline ( Pub Med ) and the search words exercise , physical activity , muscle strength , balance , falls , fractures . R and omized controlled trials ( RCT ) were predominantly included , although this not is a systematic review . Results The evidence that physical activity modifies the risk factors for fall is compelling , although RCT with fractures as end point are lacking . Physical activity is associated with improved muscle strength , co-ordination and balance .  Physical training increases muscle strength also in octogenarians by up to 200 % , i.e. a much more pronounced effect than the corresponding increase in muscle volume or bone mass . There is also evidence that physical activity decreases the actual number of falls . Observational cohort and case-control studies imply that physical activity is associated with reduced hip fracture risk . If exercise reduces the number of vertebral fractures and other fragility fractures are less evaluated . Conclusions Physical activity in older ages can be recommended to improve muscle strength and balance , to reduce the risk to fall and fractures , although the highest level of evidence – RCT with fracture as endpoint – is lacking BACKGROUND Recently , several studies have reported age-associated increases in muscle coactivation during postural control . A rigid posture induced by strong muscle coactivation reduces the degree of freedom to be organized by the postural control system . The purpose of this study was to clarify the effect of balance training on muscle coactivation during postural control in older adults . METHODS Forty-eight subjects were r and omized into an intervention ( mean age : 81.0 ± 6.9 years ) and a control group ( mean age : 81.6 ± 6.4 years ) . The control group did not receive any intervention . Postural control ability ( postural sway during quiet st and ing , functional reach , and functional stability boundary ) was assessed before and after the intervention . A cocontraction index was measured during the postural control tasks to assess muscle coactivation . RESULTS Cocontraction index values in the intervention group significantly decreased following the intervention phase for functional reach ( p < .0125 ) . Cocontraction index values had a tendency to decrease during functional stability boundary for forward and quiet st and ing tasks . Functional improvements were observed in some of the tasks after the intervention , that is , functional reach , functional stability boundary for forward , one-leg stance , and timed up and go ( p < .05 ) . CONCLUSIONS Our study raised the possibility that balance training for older adults was associated with decreases in muscle coactivation during postural control . Postural control exercise could potentially lead older adults to develop more efficient postural control strategies without increasing muscle coactivation . Further research is needed to clarify in greater detail the effects of changes in muscle coactivation BACKGROUND Older adults show increased risk of falling and major risk factors include impaired lower extremity muscle strength and postural balance . However , the potential positive effect of biofeedback-based Nintendo Wii training on muscle strength and postural balance in older adults is unknown . METHODS This r and omized controlled trial examined postural balance and muscle strength in community-dwelling older adults ( 75±6 years ) pre- and post-10 weeks of biofeedback-based Nintendo Wii training ( WII , n = 28 ) or daily use of ethylene vinyl acetate copolymer insoles ( controls [ CON ] , n = 30 ) . Primary end points were maximal muscle strength ( maximal voluntary contraction ) and center of pressure velocity moment during bilateral static stance . RESULTS Intention-to-treat analysis with adjustment for age , sex , and baseline level showed that the WII group had higher maximal voluntary contraction strength ( 18 % ) than the control group at follow up ( between-group difference = 269 N , 95 % CI = 122 ; 416 , and p = .001 ) . In contrast , the center of pressure velocity moment did not differ ( 1 % ) between WII and CON at follow-up ( between-group difference = 0.23 mm(2)/s , 95 % CI = -4.1 ; 4.6 , and p = .92 ) . For secondary end points , pre-to-post changes favoring the WII group were evident in the rate of force development ( p = .03 ) , Timed Up and Go test ( p = .01 ) , short Falls Efficacy Scale-International ( p = .03 ) , and 30-second repeated Chair St and Test ( p = .01 ) . Finally , participants rated the Wii training highly motivating at 5 and 10 weeks into the intervention . CONCLUSIONS Biofeedback-based Wii training led to marked improvements in maximal leg muscle strength ( maximal voluntary contraction ; rate of force development ) and overall functional performance in community-dwelling older adults . Unexpectedly , static bilateral postural balance remained unaltered with Wii training . The high level of participant motivation suggests that biofeedback-based Wii exercise may ensure a high degree of compliance to home- and /or community-based training in community-dwelling older adults Although much has been learned in recent decades about the deterioration of muscular strength , gait adaptations , and sensory degradation among older adults , little is known about how these intrinsic changes affect biomechanical parameters associated with slip-induced fall accidents . In general , the objective of this laboratory study was to investigate the process of initiation , detection , and recovery of inadvertent slips and falls . We examined the initiation of and recovery from foot slips among three age groups utilizing biomechanical parameters , muscle strength , and sensory measurements . Forty-two young , middle-age , and older participants walked around a walking track at a comfortable pace . Slippery floor surfaces were placed on the track over force platforms at r and om intervals without the participants ' awareness . Results indicated that younger participants slipped as often as the older participants , suggesting that the likelihood of slip initiation is similar across all age groups ; however , older individuals ? recovery process was much slower and less effective . The ability to successfully recover from a slip ( thus preventing a fall ) is believed to be affected by lower extremity muscle strength and sensory degradation among older individuals . Results from this research can help pinpoint possible intervention strategies for improving dynamic equilibrium among older adults BACKGROUND vitamin D supplementation reduces the incidence of fractures in older adults . This may be partly mediated by effects of vitamin D on neuromuscular function . OBJECTIVE to determine the effects of vitamin D supplementation on aspects of neuromuscular function known to be risk factors for falls and fractures . DESIGN r and omised , double-blind , placebo-controlled study . SETTING falls clinic taking referrals from general practitioners and accident and emergency department . SUBJECTS 139 ambulatory subjects ( > /=65 years ) with a history of falls and 25-hydroxyvitamin D ( 25OHD ) < /=12 microg/l . INTERVENTION patients were r and omised to receive a single intramuscular injection of 600,000 i.u . ergocalciferol or placebo . OUTCOME MEASURES assessment s including biochemistry , postural sway , choice reaction time ( CRT ) , aggregate functional performance time ( AFPT ) , and quadriceps strength were carried out at baseline and 6 months post-intervention . RESULTS baseline characteristics were comparable between both groups . 25OHD in the treatment group increased significantly at 6 months . AFPT deteriorated in the control group and improved in the intervention group , representing a significant difference between groups ( + 6.6 s versus -2.0 s , t = 2.80 , P < 0.05 ) . Similar changes were observed for CRT ( -0.06 s versus + 0.41 s , t = -2.52 , P < 0.01 ) and postural sway ( + 0.0025 versus -0.0138 , t = 2.35 , P < 0.02 ) . There was no significant difference in muscle strength change between groups ( -10 N versus -2 N , t = -1.26 , ns ) . A significant correlation between change in AFPT and change in 25OHD levels was observed ( r = 0.19 , P = 0.03 ) . There was no significant difference in the number of falls ( 0.39 versus 0.24 , t = 1.08 , P = 0.28 ) or fallers ( 14 versus 11 , P = 0.52 ) between two groups . CONCLUSIONS vitamin D supplementation , in fallers with vitamin D insufficiency , has a significant beneficial effect on functional performance , reaction time and balance , but not muscle strength . This suggests that vitamin D supplementation improves neuromuscular or neuroprotective function , which may in part explain the mechanism whereby vitamin D reduces falls and fractures OBJECTIVE The aim of this study was to evaluate the effect of a 10-week , high-intensity strength-training program targeting key lower extremity muscles for the purpose of improving postural control in balance-impaired older adults . METHODS A quasi-experimental , delayed entry controlled design was used to evaluate balance ability in balance-impaired older adults after participation in 10 weeks of high-intensity strength training focused on the quadriceps , hamstrings , tibialis anterior , and gastrocnemius muscles . Participants were evaluated using vali date d clinical measures of functional balance ability : the Berg Balance Scale , the Timed Up and Go , and the Activities-Specific Balance Confidence Scale . RESULTS After strength training , the exercisers were significantly stronger than the control subjects . They improved significantly on the Berg Balance Scale ( P = .030 ) from a mean score of 48.8 + /- 2.4 of 56 before training to 51.2 + /- 4.3 of 56 after training . The Timed Up and Go ( P = .045 ) and the Activities-Specific Balance Confidence Scale ( P = .038 ) also improved significantly in the experimental group . These changes are associated with a decrease in fall risk . CONCLUSIONS High-intensity strength training can safely and effectively strengthen lower extremity muscles in balance-impaired older adults , result ing in significant improvements in functional balance ability and decreased fall risk BACKGROUND & AIM Sarcopenia , the age-related decrease in muscle mass , strength , and function , is a main cause of reduced mobility , increased falls , fractures and nursing home admissions . Cross-sectional and prospect i ve studies indicate that sarcopenia may be influenced in part by reversible factors like nutritional intake . The aim of this study was to compare functional and nutritional status , body composition , and quality of life of older adults between age and sex-matched older adults with and without sarcopenia . METHODS In a multi-centre setting , non-sarcopenic older adults ( n = 66 , mean ± SD : 71 ± 4 y ) , i.e. Short Physical Performance Battery ( SPPB ) : 11 - 12 and normal skeletal muscle mass index , were recruited to match 1:1 by age and sex to previously recruited adults with sarcopenia : SPPB 4 - 9 and low skeletal muscle mass index . Health-related quality of life , self-reported physical activity levels and dietary intakes were measured using the EQ-5D scale and index , Physical Activity Scale for the Elderly ( PASE ) , and 3-day prospect i ve diet records , respectively . Concentrations of 25-OH-vitamin D , α-tocopherol ( adjusted for cholesterol ) , folate , and vitamin B-12 were assessed in serum sample s. RESULTS In addition to the defined components of sarcopenia , i.e. muscle mass , strength and function , reported physical activity levels and health-related quality of life were lower in the sarcopenic adults ( p < 0.001 ) . For similar energy intakes ( mean ± SD : sarcopenic , 1710 ± 418 ; non-sarcopenic , 1745 ± 513 , p = 0.50 ) , the sarcopenic group consumed less protein/kg ( -6 % ) , vitamin D ( -38 % ) , vitamin B-12 ( -22 % ) , magnesium ( -6 % ) , phosphorus ( -5 % ) , and selenium ( -2 % ) ( all p < 0.05 ) compared to the non-sarcopenic controls . The serum concentration of vitamin B-12 was 15 % lower in the sarcopenic group ( p = 0.015 ) , and all other nutrient concentrations were similar between groups . CONCLUSIONS In non-malnourished older adults with and without sarcopenia , we observed that sarcopenia substantially impacted self-reported quality of life and physical activity levels . Differences in nutrient concentrations and dietary intakes were identified , which might be related to the differences in muscle mass , strength and function between the two groups . This study provides information to help strengthen the characterization of this geriatric syndrome sarcopenia and indicates potential target areas for nutritional interventions BACKGROUND The benefit of protein supplementation on the adaptive response of muscle to exercise training in older people is controversial . OBJECTIVE To investigate the independent and combined effects of a multicomponent exercise program with and without a milk-based nutritional supplement on muscle strength and mass , lower-extremity fatigue , and metabolic markers . DESIGN A sample of 48 healthy sedentary men aged 60.8 ± 0.4 years were r and omly assigned to a 16-week multicomponent exercise training program with a milk-based supplement containing , besides proteins [ total milk proteins 4 or 10 g/day or soluble milk proteins rich in leucine ( PRO ) 10 g/day ] , carbohydrates and fat .  Body composition , muscle mass and strength , and time to task failure , an index of muscle fatigue , were measured . Blood lipid , fibrinogen , creatine phosphokinase , glucose , insulin , C-reactive protein , interleukin-6 , tumor necrosis factor-α soluble receptors , and endothelial markers were assessed . RESULTS Body fat mass was reduced after the 4-month training program in groups receiving 10 g/day of protein supplementation ( P < .01 ) . The training program sustained with the daily 10 g/day PRO was associated with a significant increase in dominant fat free mass ( + 5.4 % , P < .01 ) and in appendicular muscle mass ( + 4.5 % , P < .01 ) . Blood cholesterol was decreased in the trained group receiving 10 g/day PRO . The index of insulin resistance ( homeostasis model assessment -insulin resistance ) and blood creatine phosphokinase were reduced in the groups receiving 10 g/day PRO , irrespective of exercise . The inflammatory and endothelial markers were not different between the groups . Training caused a significant improvement ( + 10.6 % to 19.4 % , P < .01 ) in the maximal oxygen uptake . Increased maximum voluntary contraction force was seen in the trained groups receiving 10 g/day of proteins ( about 3 % , P < .05 ) . Time to task failure was improved in the trained participants receiving a 10 g/day supplementation with PRO ( P < .01 ) . CONCLUSIONS Soluble milk proteins rich in leucine improved time to muscle failure and increase in skeletal muscle mass and strength after prolonged multicomponent exercise training in healthy older men OBJECTIVES This study examined the benefits of and differences between 12 weeks of thrice-weekly supervised balance training and an unsupervised at-home balance activity ( using the Nintendo Wii Fit ) for improving balance and reaction time and lowering falls risk in older individuals with type 2 diabetes mellitus ( T2DM ) . DESIGN Before-after trial . SETTING University research laboratory , home environment . PARTICIPANTS Sixty-five older adults with type 2 diabetes were recruited for this study . Participants were r and omly allocated to either supervised balance training ( mean age 67.8 ± 5.2 ) or unsupervised training using the Nintendo Wii Fit balance board ( mean age 66.1 ± 5.6 ) . INTERVENTION The training period for both groups lasted for 12 weeks . Individuals were required to complete three 40-minute sessions per week for a total of 36 sessions . MEASUREMENT The primary outcome measure was falls risk , which was as derived from the physiological profile assessment . In addition , measures of simple reaction time , lower limb proprioception , postural sway , knee flexion , and knee extension strength were also collected . Persons also self-reported any falls in the previous 6 months . RESULTS Both training programs result ed in a significant lowering of falls risk ( P < .05 ) . The reduced risk was attributable to significant changes in reaction times for the h and ( P < .05 ) , foot ( P < .01 ) , lower-limb proprioception ( P < .01 ) , and postural sway ( P < .05 ) . CONCLUSIONS Overall , training led to a decrease in falls risk , which was driven by improvements in reaction times , lower limb proprioception , and general balance ability . Interestingly , the reduced falls risk occurred without significant changes in leg strength , suggesting that interventions to reduce falls risk that target intrinsic risk factors related to balance control ( over muscle strength ) may have positive benefits for the older adult with T2DM at risk for falls Multimodal exercise programs incorporating traditional progressive resistance training ( PRT ) , weight-bearing impact training and /or balance training are recommended to reduce risk factors for falls and fracture . However , muscle power , or the ability to produce force rapidly , has emerged as a more crucial variable to functional decline than muscle strength or mass . The aim of this 12-month community-based r and omized controlled trial , termed Osteo-cise : Strong Bones for Life , was to evaluate the effectiveness and feasibility of a multimodal exercise program incorporating high-velocity (HV)-PRT , combined with an osteoporosis education and behavioral change program , on bone mineral density ( BMD ) , body composition , muscle strength and functional muscle performance in older adults . Falls incidence was evaluated as a secondary outcome . A total of 162 older adults ( mean ± SD ; 67 ± 6 years ) with risk factors for falls and /or low BMD were r and omized to the Osteo-cise program ( n = 81 ) or a control group ( n = 81 ) . Exercise consisted of fitness center-based HV-PRT , weight-bearing impact and challenging balance/mobility activities performed three times weekly . After 12 months , the Osteo-cise program led to modest but significant net gains in femoral neck and lumbar spine BMD ( 1.0 % to 1.1 % , p < 0.05 ) , muscle strength ( 10 % to 13 % , p < 0.05 ) , functional muscle power ( Timed Stair Climb , 5 % , p < 0.05 ) and dynamic balance ( Four Square Step Test 6 % , p < 0.01 ; Sit-to-St and , 16 % , p < 0.001 ) relative to controls . There was no effect on total body lean mass or mobility ( timed-up- and -go ) , and no difference in falls rate ( incidence rate ratio [ IRR ] , 1.22 ; 95 % confidence interval [ CI ] , 0.72 - 2.04 ) . In conclusion , this study demonstrates that the Osteo-cise : Strong Bones for Life community-based , multimodal exercise program represents an effective approach to improve multiple musculoskeletal and functional performance measures in older adults with risk factors for falls and /or low BMD . Although this did not translate into a reduction in the rate of falls , further large-scale trials are needed to evaluate the efficacy of this multimodal approach on reducing falls and fracture Summary There is no clear consensus on definition , cut-points or st and ardised assessment s of sarcopenia . We found a lower limb strength assessment  was at least as effective in predicting balance , mobility and falls in 419 older people as muscle mass-based measures of sarcopenia . Introduction There is currently no consensus on the definition , cut-points or st and ardised assessment s of sarcopenia . This study aim ed to investigate whether several published definitions of sarcopenia differentiate between older people with respect to important functional and health outcomes . Methods Four hundred nineteen community-living older adults ( mean age 81.2 ± 4.5 , 49 % female ) completed assessment s of body composition ( dual-energy X-ray absorptiometry ) , strength , balance , mobility and disability . Falls were recorded prospect ively for a year using monthly calendars . Sarcopenia was defined according to four skeletal mass-based definitions , two strength-based definitions ( h and grip or knee extensor force ) and a consensus algorithm ( low mass and low strength or slow gait speed ) . Obesity was defined according to percentage fat mass or waist circumference . Results The four skeletal mass-based definitions varied considerably with respect to the percentage of participants classified as sarcopenic and their predictive accuracy for functional and health outcomes . The knee extension strength-based definition was equivalent to or better than the mass-based and consensus algorithm definitions ; i.e. weaker participants performed poorly in tests of leaning balance , stepping reaction time , gait speed and mobility . They also had higher physiological fall risk scores and were 43 % more likely to fall at home than their stronger counterparts . Adding obesity to sarcopenia definitions identified participants with greater self-reported disability . Conclusions A simple lower limb strength assessment was at least as effective in predicting balance , functional mobility and falls in older people as more expensive and time-consuming muscle mass-based measures . These findings imply that functional terms such as muscle weakness or motor impairment are preferable to sarcopenia Background : Balance and strength training can reduce seniors ' fall risk up to 50 % . Available evidence suggests that acute bouts of neuromuscular and endurance exercise deteriorate postural control . High-intensity endurance training has been successfully applied in different population s. Thus , it seemed valuable to examine the acute effects of high-intensity interval training ( HIIT ) on neuromuscular performance in seniors and young adults . Objective : The acute impact of a HIIT session on balance performance and muscle activity after exercise cessation and during post-exercise recovery was examined in young and old adults . We intended to investigate whether a transient exercise-induced fall-risk may occur in both groups . Methods : 20 healthy seniors ( age 70 ( SD 4 ) years ) and young adults ( age 27 ( SD 3 ) years ) were examined on 3 days . After exhaustive ramp-like treadmill testing in order to determine maximal heart rate ( HRmax ) on the first day , either a 4 × 4 min HIIT at 90 % of HRmax or a control condition ( CON ) was r and omly performed on the second and third day , respectively . Balance performance ( postural sway ) was assessed during single limb stance with open eyes ( SLEO ) and double limb stance with closed eyes ( DLEC ) . EMG was recorded for the soleus ( SOL ) , anterior tibialis ( TIB ) , gastrocnemius ( GM ) and peroneus longus ( PL ) muscles at the dominant leg . All measures were collected before , immediately as well as 10 , 30 and 45 min after HIIT and CON , respectively . Results : Compared to CON , HIIT induced significant increases of postural sway immediately after exercise cessation during SLEO in both groups ( adults : p < 0.001 , Δ = + 25 % sway ; seniors : p = 0.007 , Δ = + 15 % sway ) . Increased sway during DLEC was only found for seniors immediately and 10 min after HIIT ( post : p = 0.003 , Δ = + 14 % sway , 10 min post : p = 0.004 , Δ = + 18 % sway ) . Muscle activity was increased during SLEO for TIB until 10 min post in seniors ( 0.008 < p < 0.03 ) and immediately after HIIT in adults ( p < 0.001 ) . Conclusion : HIIT training may cause an acute ‘ open-fall-window ' with a transient impairment of balance performance for at least 10 min after exercise cessation in both groups . Occluded vision in seniors seems to prolong this period up to 30 min . Thus , the advantage of HIIT with regard to time efficiency seems debatable when considering transient HIIT-induced impairments of neuromuscular function Introduction Older breast cancer survivors ( BCS ) report more falls and functional limitations than women with no cancer history .  Exercise training could reduce risk factors for future falls and disability . Methods We conducted a r and omized , controlled trial in 106 early-stage , postmenopausal BCS who were ≥50 years old at diagnosis and post-treatment . Women were r and omly assigned to a 1-year resistance + impact exercise program or a stretching placebo program . Endpoints were one repetition maximum bench press and leg press strength , timed five chair st and s , 4 m usual walk speed , timed stance tests , h and grip strength , self-report physical function , and fatigue . We also examined the influence of age , adjuvant hormone therapy use , and exercise adherence on study outcomes . Results Women in the resistance + impact training program significantly improved maximal leg ( p < 0 .02 ) and bench ( p < 0 .02 ) press strength compared to the stretching group . Women who attended 50 % or more of prescribed resistance training sessions had significantly better changes in maximal strength measures compared to less adherent women . Conclusions Resistance + impact exercise is superior to stretching at improving maximal muscle strength and exercise adherence contributes to the degree of improvement . Implication s for cancer survivorsOlder BCS can safely engage in resistance exercise that improves lower and upper body strength , thereby reducing a risk factor for falls and future disability . However , the ability of resistance training to shift other indices of fall and disability risk , i.e. , balance and function , is unclear . Strategies to promote adherence to resistance training could lead to greater improvements in strength AIMS AND OBJECTIVES This research explores the compliance by older people in Taiwan with wearing hip protectors and whether protectors can prevent fractures or decrease injuries after falls . BACKGROUND The ageing process causes degeneration of nerves , joints , muscles and then the incidence of falls in the older people is higher than in the young . Therefore , fractures caused by falls , particularly hip fractures of older people , need to be studied . Hip protectors are design ed to reduce hip fractures and hip injuries when falls occur , by distributing the impact load and absorbing the impact force generated during a fall . DESIGN This research was design ed as a longitudinal study using purposive sampling and intervention for six months . METHODS The target population were older people at high risk for falls and the study was carried out during a six-month period . Self-reported data were collected by interview and question naires . The expert validity of the question naires , including demographics , high-risk group , compliance and correct wearing of hip protectors and fall injuries , as assessed by three experts , was 0.94 and the test-retest correlation coefficient was 0.95 . Individuals were excluded from the research sample if they were 24-hour bedridden , non-mobile or had an existing hip injury . RESULTS Ten female subjects participated in this study . Their mean age was 76.1 years . During a six-month follow-up , there were 12 falls while wearing hip protectors , however , no fractures occurred because of the falls . CONCLUSIONS This is the first research into hip protectors in Taiwan . The reasons for low compliance by older people were ( 1 ) unaccustomed to use , ( 2 ) discomfort , ( 3 ) wearing only during the daytime , ( 4 ) lack of assistance from family caregivers . RELEVANCE TO CLINICAL PRACTICE Fall prevention , exercise and the use of hip protectors can significantly decrease the incidence of hip fractures . Although hip protectors are effective in reducing fall fracture risk , the compliance rate remains low . In the future , the research ers will develop a hip protector program related to teaching the correct method for wearing protectors . Helping older people learn how to overcome the discomfort of wearing hip protectors and encouraging a willingness to wear them is imperative OBJECTIVE To determine the short-term effectiveness of a biofeedback-based , computerized intervention that applied the principles of the ecological theory of perception and control of bodily orientation to the rehabilitation of older adults with a history of falling . PARTICIPANTS Forty-five older adults ( X = 78.5 years ) with a history of falls were assigned to either a control ( n = 21 ) or intervention group ( n = 24 ) . DESIGN A 2 x 2 ( Group x Time ) mixed factorial design with repeated measures on the second factor . SETTING A motor control research laboratory in a university setting . MEASUREMENT Impairments in multiple dimensions of balance ( i.e. , dynamic postural control and sensory organization ) were measured before and after an 8-week balance intervention using the 100 % Limits of Stability Test and Sensory Organization Test . More functional limitations in balance and /or mobility were measured using two clinical tests : Berg Balance Scale and Timed Up and Go test . MAIN RESULTS Repeated measures multivariate analyses and follow-up testing indicated significant improvements in the dynamic balance and sensory integration capabilities in the case of the intervention group only ( P < .03 ) . Significant improvements were also observed in the two clinical measures of balance and mobility evaluated before and after the intervention for the intervention group only . CONCLUSIONS Theory-driven rehabilitation programs that focus on manipulating individual , task , and environmental constraints concurrently can significantly improve the control of bodily orientation of older adults with a previous history of falls in both static and dynamic action environments . Moreover , the significant improvements in functional performance observed for the intervention group suggest that interventions emphasizing task-specific practice are not the only means by which an older adult 's ability to perform daily activities requiring postural control can be improved Purpose To evaluate whether rehabilitation of muscle force or balance improves postural stability and quality of life ( QoL ) , and whether self-administered training is comparable with guided training among older adults residing in an institutional setting . Patients and methods A r and omized , prospect i ve intervention study was undertaken among 55 elderly patients . Three intervention groups were evaluated : a muscle force training group ; a balance and muscle force training group ; and a self-administered training group . Each group underwent 1-hour-long training sessions , twice a week , for 3 months . Postural stability was measured at onset , after 3 months , and after 6 months . Time-domain-dependent body sway variables were calculated . The fall rate was evaluated for 3 years . General health related quality of life ( HRQoL ) was measured with a 15D instrument . Postural stability was used as a primary outcome , with QoL and falls used as secondary outcomes . Results Muscle force trainees were able to undertake training , progressing towards more strenuous exercises . In posturography , the number of spiky oscillations was reduced after training , and stationary fields of torque moments of the ankle increased , providing better postural stability in all groups ; in particular , the zero crossing rate of weight signal and the number of low variability episodes in the stabilogram were improved after training . While no difference was found between different training groups in posturography outcomes , a reduction of fall rate was significant in only the guided training groups . A significant part of the variability of the QoL could be explained by the posturography outcome ( 46 % ) . However , the outcome of training was associated with a reduced QoL. Conclusion Even moderate or severely demented residents could do exercises in five-person groups under the supervision of a physiotherapist . An improvement in postural stability was observed in all training groups , indicating that even self-administered training could be beneficial . Posturography outcome indicated that training alters the postural strategy by reducing the oscillatory fluctuations of body sway signal . However , only guided training tended to reduce falls .  Short training intervention programs may decrease QoL by changing the elderly ’s daily routine and making it more active and exhausting BACKGROUND Muscle size and strength decrease with aging , and the result ant muscle weakness has been implicated in increased risk of falls in older adults . These falls have large economic and functional costs . METHODS The purpose of this r and omized , controlled study was to determine if an 8-week , 3-day per week intense ( 77.8 + /- 3.4 % of 1-repetition maximum [ 1RM ] ) strength training program could improve functional ability related to the risk of falling in subjects aged 61 - -87 years ( mean 72 , SD 6.3 ) . Twelve strength-training-naive subjects performed two sets of 10 repetitions for six lower body exercises while 12 subjects served as nonintervention controls . Subjects were tested pre- , mid- , and postintervention for strength gain and on three tests of functional ability . RESULTS Postintervention strength was significantly better ( p < .017 ) in all training subjects across all exercises , and no injuries were reported as a result of either training or 1RM testing . After controlling for preintervention differences , repeated measure analysis of covariance ( ANCOVA ) found a significant difference between experimental and nonintervention control subjects for postintervention maximal walking speed [ F(1,19 ) = 5.03 , p < .05 ] . There were no significant between-group differences for 1-leg blind balance time or 5-repetition sit-to-st and performance [ F(1,19 ) = .082 ; F(1,19 ) = .068 , respectively , p > .05 ] . CONCLUSIONS These findings suggest that strength training alone does not appear to enhance st and ing balance or sit-to-st and performance in active , community-dwelling older adults but that it may improve maximal walking speed . The relationship between strength gain and risk of falls remains unclear . The data do reinforce the notion that intense strength training is a safe and effective way to increase muscle strength in this population Background and Purpose : Age-related changes in the ability to adjust to alterations in sensory information contribute to impaired postural stability . The purpose of this r and omized controlled trial was to investigate the effect of sensory-specific balance training on proprioceptive reintegration . Subjects : The subjects of this study were 36 older participants who were healthy . Methods : Participants were r and omly assigned to a  balance exercise group  ( n=17 ) or a falls prevention education group ( n=19 ) . The primary outcome measure was the center-of-pressure ( COP ) velocity change score . This score represented the difference between COP velocity over 45 seconds of quiet st and ing and each of six 5-second intervals following proprioceptive perturbation through vibration with or without a secondary cognitive task . Clinical outcome measures included the Fullerton Advanced Balance ( FAB ) Scale and the Activities-specific Balance Confidence ( ABC ) Scale . Assessment s were conducted at baseline , postintervention , and at an 8-week follow-up . Results : Following the exercise intervention , there was less destabilization within the first 5 seconds following vibration with or without a secondary task than there was at baseline or in the falls prevention education group . These training effects were not maintained at the 8-week follow-up . Postintervention improvements also were seen on the FAB Scale and were maintained at follow-up . No changes in ABC Scale scores were identified in the balance exercise group , but ABC Scale scores indicated reduced balance confidence in the falls prevention education group postintervention . Discussion and Conclusion : The results of this study support short-term enhanced postural responses to proprioceptive reintegration following a sensory-specific balance exercise program
CONCLUSION On the basis of systematic review of relevant literature , it appears that muscle fatigue induces clear deteriorations in reactive postural control .
BACKGROUND Falls are the leading cause of traumatic brain injury and fractures and the No. 1 cause of emergency department visits by older adults .
Although declines in muscle strength and sensory function contribute to increased falls in older adults , skeletal muscle fatigue is often overlooked as an additional contributor to fall risk .
In an effort to increase awareness of the detrimental effects of skeletal muscle fatigue on postural control , we sought to systematic ally review research studies examining this issue .
PURPOSE The specific purpose of this review was to provide a detailed assessment of how anticipatory and reactive postural control tasks are influenced by  acute muscle fatigue in healthy older individuals .