title: Age and gender comparisons of muscle strength in 654 women and men aged 20-93 yr. Vitamin D supplementation has no effect on insulin resistance assessment in women with polycystic ovary syndrome and vitamin D deficiency. Epidemiology of sarcopenia among the elderly in New Mexico. Effects of an omnivorous diet compared with a lactoovovegetarian diet on resistance-training-induced changes in body composition and skeletal muscle in older men. Nutrient-rich dairy proteins improve appendicular skeletal muscle mass and physical performance, and attenuate the loss of muscle strength in older men and women subjects: a single-blind randomized clinical trial Elderly women accommodate to a low-protein diet with losses of body cell mass, muscle function, and immune response. Association of protein intake with the change of lean mass among elderly women: The Osteoporosis Risk Factor and Prevention – Fracture Prevention Study (OSTPRE-FPS) Serum phosphate and mortality in patients with chronic kidney disease. Dairy augmentation of total and central fat loss in obese subjects Protein supplementation improves physical performance in frail elderly people: a randomized, double-blind, placebo-controlled trial. The effects of a higher protein intake during energy restriction on changes in body composition and physical function in older women. Physiological effects beyond the significant gain in muscle mass in sarcopenic elderly men: evidence from a randomized clinical trial using a protein-rich food Two-Year Whey Protein Supplementation Did Not Enhance Muscle Mass and Physical Function in Well-Nourished Healthy Older Postmenopausal Women. The response of muscle protein anabolism to combined hyperaminoacidemia and glucose-induced hyperinsulinemia is impaired in the elderly. Soy-Dairy Protein Blend or Whey Protein Isolate Ingestion Induces Similar Postexercise Muscle Mechanistic Target of Rapamycin Complex 1 Signaling and Protein Synthesis Responses in Older Men1234 Sexually dimorphic patterns of nutritional intake and eating behaviors in community-dwelling older adults with normal and slow gait speed Similar effects of leucine rich and regular dairy products on muscle mass and functions of older polymyalgia rheumatica patients: A randomized crossover trial Muscle quality. I. Age-associated differences between arm and leg muscle groups. Vitamin D3 and calcium to prevent hip fractures in elderly women. Protein supplementation increases muscle mass gain during prolonged resistance-type exercise training in frail elderly people: a randomized, double-blind, placebo-controlled trial. Protein Supplements Increase Serum Insulin-Like Growth Factor-I Levels and Attenuate Proximal Femur Bone Loss in Patients with Recent Hip Fracture Effect of low- and high-calcium dairy-based diets on macronutrient oxidation in humans. Associations between dietary nutrient intake and muscle mass and strength in community-dwelling older adults: the Tasmanian Older Adult Cohort Study.
abstract: To assess age and gender differences in muscle strength , isometric , concentric ( Con ) , and eccentric ( Ecc ) peak torque was measured in the knee extensors at a slow ( 0.52 rad/s ) and fast ( 3.14 rad/s ) velocity in 654 subjects ( 346 men and 308 women , aged 20 - 93 yr ) from the Baltimore Longitudinal Study of Aging . Regression analysis revealed significant ( P < 0.001 ) age-related reductions in Con and Ecc peak torque for men and women at both velocities , but no differences were observed between the gender groups or velocities . Age explained losses in Con better than Ecc peak torque , accounting for 30 % ( Con ) vs. 19 % ( Ecc ) of the variance in men and 28 % ( Con ) vs. 11 % ( Ecc ) in women . To assess age and gender differences in the ability to store and utilize elastic energy , the stretch-shortening cycle was determined in a subset of subjects ( n = 47 ) . The older women ( mean age = 70 yr ) showed a significantly greater enhancement in the stretch-shortening cycle , compared with men of similar age ( P < 0.01 ) and compared with younger men and women ( each P < 0.05 ) . Both men and women showed significant declines in muscle quality for Con peak torque ( P < 0.01 ) , but no gender differences were observed . Only the men showed a significant decline in muscle quality ( P < 0.001 ) for Ecc peak torque . Thus both men and women experience age-related losses in isometric , Con , and Ecc knee extensor peak torque ; however , age accounted for less of the variance in Ecc peak torque in women , and women tend to better preserve muscle quality with age for Ecc peak torque . In addition , older women have an enhanced capacity to store and utilize elastic energy compared with similarly aged men as well as with younger women and men Insulin resistance is one of the most common features of polycystic ovary syndrome ( PCOS ) . Some studies suggest that vitamin D deficiency may have a role in insulin resistance ; thus , the aim of the current study was to determine the effect of vitamin D supplementation on insulin resistance in women with PCOS and a vitamin D deficiency . We hypothesized that vitamin D supplementation would lower the glucose level and insulin resistance in women with PCOS and a vitamin D deficiency . The current study was a r and omized , placebo-controlled , double-blinded trial with 50 women with PCOS and a vitamin D deficiency , 20 to 40 years old , assigned to receive 3 oral treatments consisting of 50,000 IU of vitamin D₃ or a placebo ( 1 every 20 days ) for 2 months ( vitamin D , n = 24 ; placebo , n = 26 ) . The fasting blood glucose , insulin , 25-hydroxyvitamin D , and parathyroid hormone levels , as well as the homeostasis model assessment of insulin resistance and quantitative insulin sensitivity check index were measured at baseline and after treatment . In the vitamin D group , the serum level of 25-hydroxyvitamin D increased ( 6.9 ± 2.8 to 23.4 ± 6.1 ng/mL , P < .0001 ) , and the parathyroid hormone level decreased ( 70.02 ± 43.04 to 50.33 ± 21.99 μ IU/mL , P = .02 ) . There were no significant changes in the placebo group . There was a significant increase in insulin secretion in the vitamin D group ( P = .01 ) , but this was not significant compared with the placebo group . The fasting serum insulin and glucose levels and the insulin sensitivity and homeostasis model assessment of insulin resistance did not change significantly by the end of the study . We were not able to demonstrate the effect of vitamin D supplementation on insulin sensitivity and insulin resistance in women with PCOS and vitamin D deficiency 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 BACKGROUND Very limited data suggest that meat consumption by older people may promote skeletal muscle hypertrophy in response to resistance training ( RT ) . OBJECTIVE The objective of this study was to assess whether the consumption of an omnivorous ( meat-containing ) diet would influence RT-induced changes in whole-body composition and skeletal muscle size in older men compared with a lactoovovegetarian ( LOV ) ( meat-free ) diet . DESIGN Nineteen men aged 51 - 69 y participated in the study . During a 12-wk period of RT , 9 men consumed their habitual omnivorous diets , which provided approximately 50 % of total dietary protein from meat sources ( beef , poultry , pork , and fish ) ( mixed-diet group ) . Another 10 men were counseled to self-select an LOV diet ( LOV-diet group ) . RESULTS Maximal strength of the upper- and lower-body muscle groups that were exercised during RT increased by 10 - 38 % ( P < 0.001 ) , independent of diet . The RT-induced changes in whole-body composition and skeletal muscle size differed significantly between the mixed- and LOV-diet groups ( time-by-group interactions , P < 0 . 05 ) . With RT , whole-body density , fat-free mass , and whole-body muscle mass increased in the mixed diet group but decreased in the LOV- diet group . Type II muscle fiber area of the vastus lateralis muscle increased with RT for all men combined ( P < 0.01 ) , and the increase tended to be greater in the mixed-diet group ( 16.2 + /- 4.4 % ) than in the LOV diet group ( 7.3 + /- 5.1 % ) . Type I fiber area was unchanged with RT in both diet groups . CONCLUSION Consumption of a meat-containing diet contributed to greater gains in fat-free mass and skeletal muscle mass with RT in older men than did an LOV diet Background At present , it is unknown whether the use of nutrient-rich dairy proteins improves the markers of sarcopenia syndrome . Therefore , our proposal was to investigate whether adding 210 g of ricotta cheese daily would improve skeletal muscle mass , h and grip strength , and physical performance in non-sarcopenic older subjects . Subjects and methods This was a single-blind r and omized clinical trial that included two homogeneous , r and omized groups of men and women over 60 years of age . Participants in the intervention group were asked to consume their habitual diet but add 210 g of ricotta cheese ( IG/HD + RCH ) , while the control group was instructed to consume only their habitual diet ( CG/HD ) . Basal and 12-week follow-up measurements included appendicular skeletal muscle mass ( ASMM ) by dual-energy X-ray absorptiometry , h and grip strength by a h and held dynamometer , and physical performance using the short physical performance battery ( SPPB ) and the stair-climb power test ( SCPT ) . The main outcomes were relative changes in ASMM , strength , SPPB , and SCPT . Results ASMM increased in the IG/HD + RCH ( 0.6±3.5 kg ) , but decreased in the CG/HD ( −1.0±2.6 ) . The relative change between groups was statistically significant ( P=0.009 ) . The relative change in strength in both groups was negative , but the loss of muscle strength was more pronounced in CG/HD , though in this regard statistical analysis found only a tendency ( P=0.07 ) . The relative change in the balance-test scores was positive for the IG/HD + RCH , while in the CG/HD it was negative , as those individuals had poorer balance . In this case , the relative change between groups did reach statistical significance . Conclusion The addition of 210 g of ricotta cheese improves ASMM and balance-test scores , while attenuating the loss of muscle strength . These results suggest that adding ricotta cheese to the habitual diet is a promising dietetic strategy that may improve the markers of sarcopenia in subjects without a pronounced loss of ASMM or sarcopenia A 9-wk study of adaptation to marginal protein intakes was conducted in 12 elderly women . Subjects were r and omly assigned to two groups fed a weight-maintenance diet containing either 1.47 ( low ) or 2.94 ( adequate ) g protein.kg body cell mass-1.d-1 ( 0.45 and 0.92 g.kg body wt-1.d-1 , respectively ) . Mean nitrogen balance in the low-protein group remained negative throughout the study . These subjects experienced significant losses in lean tissue , immune response , and muscle function . The adequate-protein group was in nitrogen balance throughout the study , without changes in lean tissue , and with improvements in immune response , serum immunoglobulins , albumin , total protein values , and muscle function . Thus , elderly women fed the low-protein diet accommo date d to the diet by compromising functional capacity , whereas those fed the adequate diet maintained functional capacity Low protein intake can lead to declined lean mass ( LM ) in elderly . We examined the associations of total protein ( TP ) , animal protein ( AP ) and plant protein ( PP ) intakes with LM . The association of TP intake with LM change was further evaluated according to weight change status . This cross-sectional and prospect i ve cohort study included 554 women aged 68 ( sd 1·9 ) years from the Osteoporosis Risk Factor and Prevention – Fracture Prevention Study ( OSTPRE-FPS ) . The intervention group ( n 270 ) received daily cholecalciferol ( 800 IU ; 20 μg ) and Ca ( 1000 mg ) for 3 years while the control group received neither supplementation nor placebo ( n 282 ) . Participants filled out a question naire on lifestyle factors and a 3-d food record in 2002 and underwent dual-energy X-ray absorptiometry for body composition measurements at baseline and 3 years . Multiple linear regressions evaluated the association between protein intake and LM , adjusting for relevant covariates . At the baseline TP and AP intakes were positively associated with LM and trunk LM , TP was associated also with appendicular LM ( aLM ) . Follow-up results showed that in the total population and the intervention group  , higher TP and AP were associated with increased LM and aLM ( P ≤ 0·050 ) . No such associations were observed in the control  group . PP intake was also associated with aLM change in the total population . Overall , the associations were independent of fat mass . Further , among weight maintainers , TP intake was positively associated with LM , aLM and trunk LM changes ( P ≤ 0·020 ) . In conclusion , dietary  TP , especially AP , intake may be a modifiable risk factor for sarcopenia by preserving LM in the elderly BACKGROUND AND OBJECTIVES Higher phosphate is associated with mortality in dialysis patients but few prospect i ve studies assess this in nondialysis patients managed in an outpatient nephrology clinic . This prospect i ve longitudinal study examined whether phosphate level was associated with death in a referred population . DESIGN , SETTING , PARTICIPANTS & MEASUREMENTS Patients ( 1203 ) of nondialysis chronic kidney disease ( CKD ) in the Chronic Renal Insufficiency St and ards Implementation Study were assessed .  Survival analyses were performed for quartiles of baseline phosphate relative to GFR , 12-month time-averaged phosphate , and baseline phosphate according to published phosphate targets . RESULTS  Mean ( SD ) eGFR was 32 ( 15 ) ml/min per 1.73 m(2 ) , age 64 ( 14 ) years , and phosphate 1.2 ( 0.30 ) mmol/L. Cox multivariate adjusted regression in CKD stages 3 to 4 patients showed an increased risk of all-cause and cardiovascular mortality in the highest quartile compared with that in the lowest quartile of phosphate . No association was found in CKD stage 5 patients . Patients who had values above recommended targets for phosphate control had increased risk of all-cause and cardiovascular death compared with patients below target . The highest quartile compared with the lowest quartile of 12-month time-averaged phosphate was associated with an increased risk of mortality . CONCLUSIONS In CKD stages 3 to 4 patients , higher phosphate was associated with a stepwise increase in mortality . As phosphate levels below published targets ( as opposed to within them ) are associated with better survival , guidelines for phosphate in nondialysis CKD patients should be re-examined . Intervention trials are required to determine whether lowering phosphate will improve survival BACKGROUND AND OBJECTIVE : We have previously demonstrated an antiobesity effect of dietary Ca ; this is largely mediated by Ca suppression of calcitriol levels , result ing in reduced adipocyte intracellular Ca2 + and , consequently , a coordinated increase in lipid utilization and decrease in lipogenesis . Notably , dairy Ca is markedly more effective than other Ca sources . DESIGN : Obese subjects were placed on balanced deficit ( −500 kcal/day ) diets and r and omized to control ( 400–500 mg Ca/day ; n=16 ) or yogurt ( 1100 mg Ca/day ; n=18 ) treatments for 12 weeks . Dietary macronutrients and fiber were held constant at the US average . MEASUREMENTS : Body weight , body fat and fat distribution ( by dual-energy X-ray absorptiometry ) , blood pressure and circulating lipids were measured at baseline and after 12 weeks of intervention . RESULTS : Fat loss was markedly increased on the yogurt diet ( −4.43±0.47 vs −2.75±0.73 kg in yogurt and control groups ; P<0.005 ) while lean tissue loss was reduced by 31 % on the yogurt diet . Trunk fat loss was augmented by 81 % on the yogurt vs control diet ( P<0.001 ) , and this was reflected in a markedly greater reduction in waist circumference ( −3.99±0.48 vs −0.58±1.04 cm , P<0.001 ) . Further , the fraction of fat lost from the trunk was higher on the yogurt diet vs control ( P<0.005 ) . CONCLUSION : Isocaloric substitution of yogurt for other foods significantly augments fat loss and reduces central adiposity during energy restriction OBJECTIVES Protein supplementation has been proposed as an effective dietary strategy to increase skeletal muscle mass and improve physical performance in frail elderly people . Our objective was to assess the impact of 24 weeks of dietary protein supplementation on muscle mass , strength , and physical performance in frail elderly people . DESIGN / SETTING / PARTICIPANTS A total of 65 frail elderly subjects were included and r and omly allocated to either daily protein or placebo supplementation ( 15 g protein at breakfast and lunch ) . MEASUREMENTS Skeletal muscle mass ( DXA ) , muscle fiber size ( muscle biopsy ) , strength ( 1-RM ) , and physical performance ( SPPB ) were assessed at baseline , and after 12 and 24 weeks of dietary intervention . RESULTS Skeletal muscle mass did not change in the protein- ( from 45.8 ± 1.7 to 45.8 ± 1.7 kg ) or placebo-supplemented group ( from 46.7 ± 1.7 to 46.6 ± 1.7 kg ) following 24 weeks of intervention ( P > .05 ) . In accordance , type I and II muscle fiber size did not change over time ( P > .05 ) . Muscle strength increased significantly in both groups ( P < .01 ) , with leg extension strength tending to increase to a greater extent in the protein ( 57 ± 5 to 68 ± 5 kg ) compared with the placebo group ( 57 ± 5 to 63 ± 5 kg ) ( treatment × time interaction effect : P = .059 ) . Physical performance improved significantly from 8.9 ± 0.6 to 10.0 ± 0.6 points in the protein group and did not change in the placebo group ( from 7.8 ± 0.6 to 7.9 ± 0.6 points ) ( treatment × time interaction effect : P = .02 ) . CONCLUSION Dietary protein supplementation improves physical performance , but does not increase skeletal muscle mass in frail elderly people BACKGROUND The purpose of this double-blind r and omized clinical trial was to compare the relative effectiveness of a higher protein and conventional carbohydrate intake during weight loss on body composition and physical function in older women . METHODS Thirty-one overweight or obese , postmenopausal women ( mean ± SD : age 65.2 ± 4.6 years , body mass index 33.7 ± 4.9 kg/m(2 ) ) were prescribed a reduced calorie diet ( 1,400 kcal/day ; 15 % , 65 % , 30 % energy from protein , carbohydrate , and fat , respectively ) and r and omly assigned to 2 × 25 g/day whey protein ( PRO n = 15 ) or maltodextrin ( CARB n = 16 ) supplementation for 6 months  . Lean soft tissue ( LST ) via dual-energy X-ray absorptiometry ; thigh muscle , subcutaneous adipose tissue ( SAT ) , and intermuscular adipose tissue with magnetic resonance imaging ; knee strength with isokinetic dynamometry ; balance and physical function with a battery of performance tests . RESULTS PRO lost more weight than CARB ( -8.0 % ± 6.2 % , -4.1 % ± 3.6 % , p = .059 ; respectively ) . Changes in LST , % LST , and strength , balance , or physical performance measures did not differ between groups ( all p > .05 ) . Weight to leg LST ratio improved more in PRO versus CARB ( -4.6 ± 3.6 % , -1.8 ± 2.6 % , p = .03 ) . PRO lost 4.2 % more muscle ( p = .01 ) , 10.9 % more SAT ( p = .02 ) , and 8.2 % more intermuscular adipose tissue ( p = .03 ) than CARB . Relative to thigh volume changes , PRO gained 5.8 % more muscle ( p = .049 ) and lost 3.8 % greater SAT ( p = .06 ) than CARB . Weight to leg LST ratio ( r(2 ) = .189 , p = .02 ) and SAT ( r(2 ) = .163 , p = .04 ) predicted improved up and go , relative muscle ( r(2 ) = .238 , p = .01 ) and SAT ( r(2 ) = .165 , p = .04 ) predicted improved transfer test , and % LST predicted improved balance ( r(2 ) = .179 , p = .04 ) . CONCLUSIONS A higher protein intake during caloric restriction maintains muscle relative to weight lost , which in turn enhances physical function in older women Background Sarcopenia is strongly associated with an inadequate intake of dietary protein . Dietary protein supplementation boosts muscle-protein synthesis and increases muscle mass in the elderly . This study tested whether adding a protein-rich food , ricotta cheese , to the habitual diet increased total appendicular skeletal muscle mass and strength in elderly people . Methods Participants ( n = 40 ) , were sarcopenic elderly men and women over 60 years of age . Two comparison groups were formed at r and om and followed for 3 months : the intervention group received 210 g/day of ricotta cheese plus the habitual diet , while the control group followed the habitual diet with no additional intervention . Total appendicular skeletal muscle ( TASM ) was assessed by dual-energy X-ray absorptiometry , while strength was measured using a h and held dynamometer at baseline and after the intervention period . The primary outcomes were the percentage of relative change in TASM and strength . Results The percentage of relative change in TASM was not significant between the groups after the intervention period . Muscle strength improved in the intervention group , but showed only a tendency towards significance ( P = 0.06 ) . Secondary analysis showed that the men in the intervention group gained 270 g in TASM compared to those in the control group , and improved their fasting insulin levels ( P = 0.05 ) , muscle strength , lean body mass in the arms , and body weight variables . Conclusion The results of this study indicate that a nutritional intervention using a high- quality protein food , specifically ricotta cheese , in order to increase the amount of protein intake might not be regarded as fully promising in elderly men and women with sarcopenia . However , the gender effects on muscle strength , lean tissue in the arms , homeostatic assessment of insulin resistance , and body weight detected in this study suggest that additional research is needed on elderly male subjects with sarcopenia BACKGROUND Protein may play a role in preventing muscle loss with aging . To our knowledge , there have been no long-term r and omized controlled trials to examine the effects of increased dietary protein intake on muscle health in community-dwelling older women . OBJECTIVE In this study , we evaluated the effects of whey protein supplementation on muscle mass and physical function in community-dwelling older Australian women . METHODS In this 2 y r and omized , double-blind , placebo-controlled trial , women aged 70 - 80 y ( mean 74.3 ± 2.7 y ) were r and omly assigned to either a high protein drink containing 30 g of whey protein ( n = 109 ) or a placebo drink containing 2.1 g protein ( n = 110 ) daily . Dual-energy X-ray absorptiometry appendicular skeletal muscle mass , upper arm and calf ( 38 % tibia ) muscle cross-sectional area , physical function including h and grip strength , lower limb muscle strength and Timed Up and Go test , and 24 h urinary nitrogen were measured at baseline , 1 y , and 2 y. RESULTS A total of 196 women with at least one follow-up measurement were included in this analysis . Baseline mean BMI was 26.7 ± 3.9 kg/m(2 ) and protein intake was 76 ± 17 g/d ( 1.1 ± 0.3 g · kg body weight(-1 ) · d(-1 ) ) . A mean increase in protein intake of ∼ 20 g/d in the protein group was confirmed by the estimates from 24 h urinary nitrogen . Over the 2 y in both groups there was a significant decrease in the upper arm ( mean ± SE : -5.59 ± 0.75 cm(2 ) ) and calf ( -0.77 ± 0.11 cm(2 ) ) muscle area , as well as h and grip strength ( -1.30 ± 0.3 kg ) ( all P < 0.05 ) , but appendicular skeletal muscle mass did not change significantly . There were no significant effects of the protein intervention on any of the muscle mass or physical function measures ( all P > 0.05 ) at 1 and 2 y. CONCLUSION This study showed that in protein-replete , healthy , ambulant , postmenopausal older women , 30 g/d of extra protein did not improve the maintenance of muscle mass or physical function despite evidence of deterioration in muscle measurements in the upper limb . This trial was registered at the Australian New Zeal and Clinical Trials Registry as ACTRN012607000163404 Muscle mass declines with aging . Amino acids alone stimulate muscle protein synthesis in the elderly . However , mixed nutritional supplementation failed to improve muscle mass . We hypothesized that the failure of nutritional supplements is due to altered responsiveness of muscle protein anabolism to increased amino acid availability associated with endogenous hyperinsulinemia . We measured muscle protein synthesis and breakdown , and amino acid transport in healthy young ( 30 + /- 3 yr ) and elderly ( 72 + /- 1 yr ) volunteers in the basal postabsorptive state and during the administration of an amino acid-glucose mixture , using  L-[ring-(2)H(5)]phenylalanine infusion , femoral artery and vein catheterization , and muscle biopsies .  Basal muscle amino acid turnover was similar in young and elderly subjects . The mixture increased phenylalanine leg delivery and transport into the muscle in both groups . Phenylalanine net balance increased in both groups ( young , -27 + /- 8 to 64 + /- 17 ; elderly , -16 + /- 4 to 29 + /- 7 nmol/(min.100 mL ) ; P : < 0.0001 , basal vs. mixture ) , but the increase was significantly blunted in the elderly ( P : = 0.030 vs. young ) . Muscle protein synthesis increased in the young , but remained unchanged in the elderly [ young , 61 + /- 17 to 133 + /- 30 ( P : = 0 . 005 ) ; elderly , 62 + /- 9 to 70 + /- 14 nmol/(min.100 mL ) ( P : = NS ) ] . In both groups , protein breakdown decreased ( P : = 0.012 ) and leg glucose uptake increased ( P : = 0.0258 ) with the mixture . We conclude that the response of muscle protein anabolism to hyperaminoacidemia with endogenous hyperinsulinemia is impaired in healthy elderly due to the unresponsiveness of protein synthesis Background : Previous work demonstrated that a soy-dairy protein blend ( PB ) prolongs hyperaminoacidemia and muscle protein synthesis in young adults after resistance exercise . Objective : We investigated the effect of PB in older adults . We hypothesized that PB would prolong hyperaminoacidemia , enhancing mechanistic target of rapamycin complex 1 ( mTORC1 ) signaling and muscle protein anabolism compared with a whey protein isolate ( WPI ) . Methods : This double-blind , r and omized controlled trial studied men 55–75 y of age . Subjects consumed 30 g protein from WPI or PB ( 25 % soy , 25 % whey , and 50 % casein ) 1 h after leg extension exercise ( 8 sets of 10 repetitions at 70 % one-repetition maximum ) . Blood and muscle amino acid concentrations and basal and postexercise muscle protein turnover were measured by using stable isotopic methods . Muscle mTORC1 signaling was assessed by immunoblotting . Results : Both groups increased amino acid concentrations ( P < 0.05 ) and mTORC1 signaling after protein ingestion ( P < 0.05 ) . Postexercise fractional synthesis rate ( FSR ; P ≥ 0.05 ) , fractional breakdown rate ( FBR ; P ≥ 0.05 ) , and net balance ( P = 0.08 ) did not differ between groups . WPI increased FSR by 67 % ( mean ± SEM : rest : 0.05 % ± 0.01 % ; postexercise : 0.09 % ± 0.01 % ; P < 0.05 ) , decreased FBR by 46 % ( rest : 0.17 % ± 0.01 % ; postexercise : 0.09 % ± 0.03 % ; P < 0.05 ) , and made net balance less negative ( P < 0.05 ) . PB ingestion did not increase FSR ( rest : 0.07 % ± 0.03 % ; postexercise : 0.09 % ± 0.01 % ; P ≥ 0.05 ) , tended to decrease FBR by 42 % ( rest : 0.25 % ± 0.08 % ; postexercise : 0.15 % ± 0.08 % ; P = 0.08 ) , and made net balance less negative ( P < 0.05 ) . Within-group percentage of change differences were not different between groups for FSR , FBR , or net balance ( P ≥ 0.05 ) . Conclusions : WPI and PB ingestion after exercise in older men induced similar responses in hyperaminoacidemia , mTORC1 signaling , muscle protein synthesis , and breakdown . These data add new evidence for the use of whey or soy-dairy PBs as targeted nutritional interventions to counteract sarcopenia . This trial was registered at clinical trials.gov as NCT01847261 Objectives Assess sex-specific nutritional intake and dietary habits of independently living older adults with normal and slow gait speeds . Design New Mexico Aging Process Study , cross-sectional , secondary data analysis . Setting Albuquerque , New Mexico USA . Participants Three-hundred fifteen adults 60 years and older ( 194 women and 121 men ) . Measurements  Gait speed test , 3-day diet records , Mini-Mental State Examination , and body mass index . Results Slow gait speed was associated with lower total calories ( −154 kcal/day ) and zinc ( 1mg/day ) ( .05 < p < .1 ) . Slower men consumed less protein ( −4.1g/day ) ,  calcium  ( −140 mg ) , fiber  ( -2.8g/day ) and iron  ( −2.5mg/day ) ( p<.05 ) . Slower women consumed less , protein ( −5.5g/day ) , carbohydrate ( −19.1g/day ) , fiber ( −2.7gm/day ) , vitamin C ( −18.4mg/day ) and higher fat intake ( p=0.03 ) . Slower women snacked less , had trouble chewing/biting , and lived alone ( p=.04 ) . Slower men were less likely to snack . Conclusions We found sex-specific nutritional differences associated with gait speed . Those presenting with slow gait speed may need encouragement to increase meat and whole grain breads/cereal . Those with trouble eating should be advised on adapting diet to maintain adequate nutrition and encouraged on regular snacking to achieve higher nutrient intake . Prospect i ve and r and omized controlled studies are needed to confirm these findings and provide further evidence for putting these suggestions into practice Objectives Leucine-rich milk and whey proteins have been suggested for prevention of age related loss of muscle mass and strength i.e. sarcopenia . The effects of milk protein supplementation and low intensity home based physical exercise on body composition and muscle functions were investigated . Design A r and omized double blind crossover trial . Setting Community dwelling members of Helsinki rheumatoid association . Participants Older people ( N = 47 , mean age 69.5 years ) suffering from polymyalgia rheumatica . Intervention Patients performed as many st and ups as possible twice a day after which they ingested a regular ( Control ) or a whey protein enriched dairy product with high leucine content ( Test ) . The 8-week intervention periods were separated by a 4-week wash-out . Measurements Body composition was measured by dual x-ray absorptiometry and muscle functions by h and grip strength , force platform countermovement jump performance , chair st and test , and walking speed . Results The 16-week home-based post-exercise supplementation result ed in a 1.8 % increase ( p = 0.052 ) in lower limb muscle mass . Walking speed ( + 5.3 % , p = 0.007 ) and chair st and test performance ( −12.2 % , p < 0.001 ) were also improved . Furthermore , a tendency for increased jump power ( + 3.0 % , p = 0.084 ) was observed . However , significant and consistent differences were not found in the changes of muscle mass indices or muscle functions between supplements , but the test supplement tended to prevent accumulation of body fat . Conclusion A low intensity home based exercise program combined with post-exercise milk protein supplementation is feasible despite some gastrointestinal complaints and seems effective in improving the muscle mass and functions of older persons with a inflammatory disease . Further studies are needed to establish , whether and to what extent the use of leucine-enriched whey products prevent or treat age-associated sarcopenia and whether they are superior to the present commercial milk products To determine the differences between arm and leg muscle quality ( MQ ) across the adult life span in men and women , concentric ( Con ) and eccentric ( Ecc ) peak torque ( PT ) were measured in 703 subjects ( 364 men and 339 women , age range 19 - 93 yr ) and appendicular skeletal muscle mass ( MM ) was determined in the arm and leg in a subgroup of 502 of these subjects ( 224 men and 278 women ) . Regression analysis showed that MQ , defined as PT per unit of MM , was significantly higher in the arm ( approximately 30 % ) than in the leg across age in both genders ( P < 0.01 ) . Arm and leg MQ declined at a similar rate with age in men , whereas leg MQ declined approximately 20 % more than arm MQ with increasing age in women ( P < /= 0.01 and P < 0.05 for Con and Ecc PT , respectively ) . Moreover , the age-associated decrease in arm MQ was steeper in men than in women whether Con or Ecc PT was used ( both P < 0.05 ) . Arm MQ as determined by Con PT showed a linear age-related decline in men and women ( 28 and 20 % , respectively , P < 0.001 ) , whereas arm MQ as determined by Ecc PT showed a linear age-related decline in men ( 25 % , P < 0.001 ) but not in women ( not significant ) . In contrast , both genders exhibited an age-related quadratic decline in leg MQ as determined by Con PT ( approximately 40 % ) and Ecc PT ( approximately 25 % ; both P < 0.001 ) , and the rate of decline was similar for men and women . Thus MQ is affected by age and gender , but the magnitude of this effect depends on the muscle group studied and the type of muscle action ( Con vs. Ecc ) used to assess strength BACKGROUND Hypovitaminosis D and a low calcium intake contribute to increased parathyroid function in elderly persons .  Calcium and vitamin D supplements reduce this secondary hyperparathyroidism , but whether such supplements reduce the risk of hip fractures among elderly people is not known . METHODS We studied the effects of supplementation with vitamin D3 ( cholecalciferol ) and calcium on the frequency of hip fractures and other nonvertebral fractures , identified radiologically , in 3270 healthy ambulatory women ( mean [ + /- SD ] age , 84 + /- 6 years ) . Each day for 18 months , 1634 women received tricalcium phosphate ( containing 1.2 g of elemental calcium ) and 20 micrograms ( 800 IU ) of vitamin D3 , and 1636 women received a double placebo . We measured serial serum parathyroid hormone and 25-hydroxyvitamin D ( 25(OH)D ) concentrations in 142 women and determined the femoral bone mineral density at base line and after 18 months in 56 women . RESULTS Among the women who completed the 18-month study , the number of hip fractures was 43 percent lower ( P = 0.043 ) and the total number of nonvertebral fractures was 32 percent lower ( P = 0.015 ) among the women treated with vitamin D3 and calcium than among those who received placebo . The results of analyses according to active treatment and according to intention to treat were similar . In the vitamin D3-calcium group , the mean serum parathyroid hormone concentration had decreased by 44 percent from the base-line value at 18 months ( P < 0.001 ) and the serum 25(OH)D concentration had increased by 162 percent over the base-line value ( P < 0.001 ) . The bone density of the proximal femur increased 2.7 percent in the vitamin D3-calcium group and decreased 4.6 percent in the placebo group ( P < 0.001 ) . CONCLUSIONS Supplementation with vitamin D3 and calcium reduces the risk of hip fractures and other nonvertebral fractures among elderly women OBJECTIVES Protein supplementation has been proposed as an effective dietary strategy to augment the skeletal muscle adaptive response to prolonged resistance-type exercise training in elderly people . Our objective was to assess the impact of protein supplementation on muscle mass , strength , and physical performance during prolonged resistance-type exercise training in frail elderly men and women . DESIGN / SETTING / PARTICIPANTS A r and omized , double-blind , placebo-controlled trial with 2 arms in parallel among 62 frail elderly subjects ( 78 ± 1 year ) . These elderly subjects participated in a progressive resistance-type exercise training program ( 2 sessions per week for 24 weeks ) during which they were supplemented twice daily with either protein ( 2 * 15 g ) or a placebo .  MEASUREMENTS Lean body mass ( DXA ) , strength ( 1-RM ) , and physical performance ( SPPB ) were assessed at baseline , and after 12 and 24 weeks of intervention . RESULTS Lean body mass increased from 47.2 kg ( 95 % CI , 43.5 - 50.9 ) to 48.5 kg ( 95 % CI , 44.8 - 52.1 ) in the protein group and did not change in the placebo group ( from 45.7 kg , 95 % CI , 42.1 - 49.2 to 45.4 kg , 95 % CI , 41.8 - 48.9 ) following the intervention ( P value for treatment × time interaction = .006 ) . Strength and physical performance improved significantly in both groups ( P = .000 ) with no interaction effect of dietary protein supplementation . CONCLUSIONS Prolonged resistance-type exercise training represents an effective strategy to improve strength and physical performance in frail elderly people  . Dietary protein supplementation is required to allow muscle mass gain during exercise training in frail elderly people . TRIAL REGISTRATION clinical trials.gov identifier : NCT01110369 Fracture of the proximal femur is the most dramatic clinical sequela of osteoporosis [ 1 , 2 ] . It is associated with a high mortality rate , need for long-term medical care , and prolonged disability [ 3 - 5 ] . Protein malnutrition is often seen in elderly persons and is more severe in patients with hip fracture [ 6 - 11 ] . Protein deficiency may contribute to the occurrence of hip fracture by reducing muscle strength , impairing movement coordination , and diminishing the protective layer of soft tissue padding [ 9 , 10 , 12 - 14 ] It may also be associated with lower bone mineral density at the proximal femur [ 15 ] . Furthermore , malnutrition in general and protein deficiency in particular at admission and during recovery may adversely influence clinical outcome after hip fracture [ 7 , 9 , 10 , 16 - 18 ] . Protein restriction has been shown to reduce plasma levels of insulin-like growth factor-I ( IGF-I ) by inducing resistance to the action of growth hormone in the liver and increasing the metabolic clearance rate of the growth factor [ 19 - 23 ] . Furthermore , evidence shows that protein depletion may blunt the effect of IGF-I on target organs [ 20 ] . Thus , low protein intake in elderly persons may be detrimental to skeletal integrity , muscle strength , and immune response [ 11 , 24 - 27 ] because of decreased production and action of IGF-I , which favorably influences these systems [ 28 - 33 ] . Previous studies [ 16 , 17 ] have shown that a 5-week course of protein supplements can reduce the medical complication rate and duration of hospital stay in patients with recent hip fracture . These findings were independent of energy , calcium , and vitamin D intake [ 17 ] . Whether these observations were related to the restoration of decreased IGF-I levels and whether bone may benefit from long-term protein supplementation are not known . We investigated whether protein supplements in vitamin D-replete patients with a recent hip fracture who were receiving calcium supplements could increase circulating IGF-I levels and favorably influence bone mineral density . Methods Patients Patients were recruited in the orthopedic ward of Geneva University Hospital , the referral center that receives 94.6 % of all patients with hip fracture from an area with a population of approximately 400 000 persons [ 5 ] . The protocol was approved by the ethical committee of the Geneva University Hospital Department of Surgery . Inclusion criteria were age greater than 60 years ; recent hip fracture ( within 2 weeks ) attributable to osteoporosis ( that is , a fracture after a minor trauma , such as a fall from st and ing height ) ; and the ability to give written , informed consent . Exclusion criteria were pathologic fracture ; fracture caused by severe trauma ; history of contralateral hip fracture ; severe mental impairment ; active metabolic bone disease ; renal failure ( plasma creatinine concentration 200 mol/L ) ; acute illness that could interfere with the study protocol ; severe malnutrition ( serum albumin level < 15 g/L ) ; consumption of drugs known to alter bone metabolism , such as calcitonin , fluoride , sex hormones , corticosteroids , or bisphosphonates ; and life expectancy of less than 1 year . Using a r and om number table , we assigned patients to receive an oral protein supplement composed of 90 % milk proteins or a placebo made isocaloric by the addition of maltodextrins . Patients took the assigned intervention 5 days a week for 6 months in addition to their regular diet . All patients received one oral dose of vitamin D3 , 200 000 IU ( vitamine D3B.O.N. , Doms-Adrian , Courbevoie , France ) , to correct any possible vitamin D deficiency [ 34 ] . The daily protein supplement ( Meritene , S and oz Nutrition Ltd. , Berne , Switzerl and ) provided 1050 kJ ( 250 kcal ) of energy in the form of 20 g of proteins , 3.1 g of lipids , and 35.7 g of carbohydrates ( 54.4 g in placebo ) . The other constituents of the 65 g powder supplement were vitamin A ( 1000 IU ) , vitamin K1 ( 30 g ) , vitamin C ( 20 mg ) , calcium ( 550 mg ) , magnesium ( 91 mg ) , phosphorus ( 429 mg ) , and sodium ( 228 mg ) . The supplement is design ed to normalize but not overcompensate for the insufficient dietary intake of protein of elderly persons with a recent fracture of the proximal femur [ 16 ] . Compliance was verified by weekly phone calls and by counting the remaining nutritional supplement bags , which were forwarded monthly by mail . Clinical Data Medical history , clinical characteristics , anthropometric data , and performance status according to an Activities of Daily Living score [ 35 ] were evaluated . Dietary intakes were recorded by using a food-frequency question naire [ 36 ] about the week before the fracture . Food intakes were analyzed by using a nutrient software system ( Fruitdor , Astra-Calve , Paris , France ) . Dietary intake of calcium , phosphorus , and protein was calculated from intake of dairy products , meat , fish , and vegetables . Because many patients were unable to st and a few days after hip fracture , their height was determined with a fathom measure while they were recumbent . Body weight was determined with a scale that correlated highly with that provided by measurement of whole body bone , fat , and lean mass as assessed by dual x-ray absorptiometry [ 37 ] . Mid-arm circumference was measured with a tape measure ( coefficient of variation , 2 % ) . Isometric muscle strength of the biceps of the dominant arm was evaluated with a dynamometer ( Lido , Lidoactive Isokinetic System , Loredan Biomedical Inc. , West Sacramento , California ) , which measures the peak torque ( coefficient of variation < 5 % ) . The grip strength of the same arm was measured with a dynamometer ( Vigorimeter , Martin Medizin-Technik , Tuttlingen , Germany ) [ 38 ] . The mean of three measurements was used for calculation . Biochemical Data Within 120 hours after surgery , we used st and ard methods to analyze venous blood sample s for protein-corrected plasma levels of calcium , phosphate , creatinine , total proteins , albumin , and prealbumin . We also measured levels of IGF-I ( Nichols Institute , San Juan Capistrano , California ) after acid-ethanol extraction and cryoprecipitation [ 39 ] , intact parathyroid hormone ( Immulite , Diagnostic Products , Los Angeles , California ) , calcitriol , calcidiol ( Incstar , Stillwater , Minnesota ) , and osteocalcin ( CIS-BIO International , Gif-sur-Yvette , France ) . Biochemical measurements were repeated 6 and 12 months after the fracture . Serum IGF-I binding proteins were measured by Western lig and blot analysis [ 40 ] . Briefly , 3 L of serum was boiled and separated onto 15 % sodium dodecylsulfate polyacrilamide gel electrophoresis under nonreducing conditions . Proteins were electrically blotted onto a nitrocellulose membrane , and IGF-I binding proteins were detected after incubating the membranes with radioiodinated IGF-I at 4C for 24 hours . Insulin-like growth factor binding proteins were quantified by phosphorimaging ( Molecular Dynamics , Sunnyvale , California ) . The intensity of the b and s corresponding to the appropriate molecular weights [ 40 ] was expressed as the percentage of total bound radioactive IGF-I. Measurements of calcium , phosphate , and creatinine were obtained from the second fasting morning urine . The ratio of hydroxyproline to creatinine in the same sample was taken as a reflection of bone resorption . Markers of bone resorption ( pyridinoline and deoxypyridinoline ) in the first morning spot urine were measured by detecting fluorescence emission after acid hydrolysis and separation with isocratic reverse-phase high-performance liquid chromatography ( BioRad System , Munich , Germany ) , and the values were adjusted to the creatinine concentration . Immunologic Data Concentrations of IgA , IgG , IgM , and isohemagglutinins were measured by using st and ard methods . Cell-mediated immunity was assessed by using a skin-test antigens for cellular hypersensitivity system ( STACH , Institut Merieux , Lyon , France ) , which evaluates the size of the skin reaction to various antigens injected intradermally [ 41 ] . Bone Mass Assessment We measured areal bone mineral density at the lumbar spine ( anteroposterior and lateral views ) , the contralateral proximal femur ( femoral neck and trochanter ) , and the contralateral mid-femoral shaft . We also measured whole-body bone mineral content , fat , and lean mass by using dual x-ray absorptiometry ( Hologic QDR-2000 , Waltham , Massachusetts ) . The coefficients of variation of these measurements are reported elsewhere [ 37 , 42 ] . Vertebral Deformity Two series of lateral radiography of the thoracic and lumbar spine were taken at the start of the study and at 12 months . The films were examined by a single investigator ( who was unaware of treatment group assignment ) according to a 6-point analysis procedure for each vertebral body from T4 to L4 [ 43 , 44 ] ( intra-observer coefficient of variation , 1.8 % to 3.1 % ) . At baseline , fracture was defined by a decrease of 20 % in the ratio of anterior or middle height to posterior height . Patients were considered to have a new vertebral deformity if the anterior , middle , or posterior height decreased by more than 20 % between the two examinations . Statistical Analysis All values are given as the mean SD for baseline measurement and the mean SE for comparisons of outcome results . All analyses were performed by using the SAS procedure ( Cary , North Carolina ) . One-way analysis of variance was used . A two-tailed P value less than 0.05 was considered significant . Role of the Funding Sources This study was supported by grants from S and oz Nutrition Ltd. , Berne , Switzerl and , and the Swiss National Research Science Foundation . The skin-test antigens for cellular hypersensitivity system was supplied by Rhone-Poulenc , Thalwil , Switzerl and . No organization influenced the design , conduct , or reporting of the study . Results Of 842 patients evaluated from April 1992 to February 1994 , 82 were recruited into the r and omized , double-blind , placebo-controlled trial . This low enrollment rate was due to patients ' poor medical or cognitive conditions and reluctance to give informed consent . OBJECTIVE Higher calcium and dairy intakes may be associated with lower body weights , but a mechanism in humans has yet to be eluci date d. We compared the effects of a dairy-based high-calcium diet and a low-calcium diet on macronutrient oxidation . RESEARCH METHODS AND PROCEDURES Subjects ( 10 men and nine women ) consumed a low-dairy ( LD , approximately one serving per day , approximately 500 mg Ca(2+)/d ) or high-dairy ( HD , approximately three to four servings per day , approximately 1400 mg Ca(2+)/d ) energy balance diet for 1 week . Each diet condition was performed twice . On the 7th day , subjects were studied in a room calorimeter under one of four study conditions , applied in a r and omized crossover design . Within each diet condition , subjects were studied under conditions of energy balance and acute energy deficit . The deficit ( -600 kcal/d ) was induced only for the 24 hours that subjects resided in the room and was achieved by a combination of caloric restriction and exercise . RESULTS Under energy balance conditions , there was no effect of diet treatment on respiratory quotient or 24-hour macronutrient oxidation . Under energy deficit conditions , 24-hour fat oxidation was significantly increased on the HD diet ( HD with deficit = 136 + /- 13 g/d , LD with deficit = 106 + /- 7 g/d , p = 0.02 ) . DISCUSSION Consumption of a dairy-based high-calcium diet increased 24-hour fat oxidation under conditions of acute energy deficit . We hypothesize that these effects are due to an increased fat oxidation during exercise OBJECTIVES To describe associations between dietary nutrient intake and progression of sarcopenia , the age-related loss of muscle mass and strength . DESIGN Prospect i ve cohort study of community-dwelling older adults . SETTING Southern Tasmania , Australia . PARTICIPANTS Seven hundred forty noninstitutionalized older adults ( 50 % female ; mean age 62 ± 7 ) r and omly sample d from electoral rolls .  MEASUREMENTS Dietary nutrient intake  was examined at baseline and follow-up ( 2.6 ± 0.4 years later ) using The Cancer Council Victoria 's Food Frequency Question naire ( FFQ ) . Appendicular lean mass ( aLM ) was assessed using dual X-ray absorptiometry and muscle strength of the knee extensors using a dynamometer . RESULTS Failing to meet the recommended dietary intake for protein was associated with significantly lower aLM at baseline ( -0.81 kg , 95 % confidence interval ( CI ) = -1.54 to -0.08 ) and follow-up ( -0.79 kg , 95%CI = -1.42 to -0.17 ) . Energy-adjusted protein intake was a positive predictor of change in aLM over 2.6 years ( β = 0.10 , P = .003 ) . Energy-adjusted intake of iron ( β = 0.07 , P = .02 ) , magnesium ( β = 0.07 , P=.02 ) , phosphorus ( β = 0.07 , P = .047 ) , and zinc ( β = 0.08 , P = .02 ) were positive predictors of change in aLM , whereas retinol ( β = -0.09 , P = .005 ) was a negative predictor of change in aLM after adjustment for protein intake . No significant associations were observed between nutrient intake and muscle strength . CONCLUSION Protein and several other dietary nutrients are associated with muscle mass and rate of muscle loss ( but not strength ) in older adults , suggesting that multiple dietary components may ameliorate the progression of sarcopenia
target: This systematic review highlights the effects of dairy products on muscle mass , muscle strength and body performance in the elderly population in the perspective of Ca , P , vitamin D and protein
background: The risk of sarcopenia increases with aging .
  Malnutrition in the elderly population is an important risk factor for sarcopenia .
  Calcium ( Ca ) , phosphate ( P ) , vitamin D and protein are key nutrients for the human body and affect muscle mass and quality .
  Dairy products are rich in these nutrients , which implicates that dairy products might be ideal for elderly population .