Immunological changes in human skeletal muscle and blood after eccentric exercise and multiple biopsies. Reductions in C-reactive protein in older adults with type 2 diabetes are related to improvements in body composition following a randomized controlled trial of resistance training Combined training enhances skeletal muscle mitochondrial oxidative capacity independent of age. Exercise training in chronic heart failure: correlation between reduced local inflammation and improved oxidative capacity in the skeletal muscle Relationships among nutritional status and skeletal and respiratory muscle function in cystic fibrosis: does early dietary supplementation make a difference? The effect of physical training on skeletal muscle in patients with chronic heart failure. Does hyperoxia affect glucose regulation and transport in the newborn? Protein supplementation improves physical performance in frail elderly people: a randomized, double-blind, placebo-controlled trial. Effects of whey protein and resistance exercise on body cell mass, muscle strength, and quality of life in women with HIV Texture‐modified diets are associated with decreased muscle mass in older adults admitted to a rehabilitation ward Impact of Very Early Physical Therapy During Septic Shock on Skeletal Muscle: A Randomized Controlled Trial Skeletal muscle sodium glucose co-transporters in older adults with type 2 diabetes undergoing resistance training Reduction in Inflammatory Gene Expression in Skeletal Muscle from Roux-en-Y Gastric Bypass Patients Randomized to Omentectomy Heavy resistance exercise training and skeletal muscle androgen receptor expression in younger and older men Effects of resveratrol in patients with type 2 diabetes mellitus on skeletal muscle SIRT1 expression and energy expenditure. Effects of an omnivorous diet compared with a lactoovovegetarian diet on resistance-training-induced changes in body composition and skeletal muscle in older men. Bed rest promotes reductions in walking speed, functional parameters, and aerobic fitness in older, healthy adults. Effects of physical activity on strength and skeletal muscle fat infiltration in older adults: a randomized controlled trial. Qualitative Ultrasound in Acute Critical Illness Muscle Wasting Acute Ischemic Preconditioning of Skeletal Muscle Prior to Flap Elevation Augments Muscle‐Flap Survival Testosterone therapy prevents gain in visceral adipose tissue and loss of skeletal muscle in nonobese aging men. Influences on skeletal mineralization in children and adolescents: evidence for varying effects of sexual maturation and physical activity. Fatty acid composition of skeletal muscle reflects dietary fat composition in humans.
1 . A role of the immune system in muscular adaptation to physical exercise has been suggested but data from controlled human studies are scarce . The present study investigated immunological events in human blood and skeletal muscle by immunohistochemistry and flow cytometry after eccentric cycling exercise and multiple biopsies . 2 . Immunohistochemical detection of neutrophil- ( CD11b , CD15 ) , macrophage- ( CD163 ) , satellite cell- ( CD56 ) and IL-1beta-specific antigens increased similarly in human skeletal muscle after eccentric cycling exercise together with multiple muscle biopsies , or multiple biopsies only . 3 . Changes in immunological variables in blood and muscle were related , and monocytes and natural killer ( NK ) cells appeared to have governing functions over immunological events in human skeletal muscle . 4 . Delayed onset muscle soreness , serum creatine kinase activity and C-reactive protein concentration were not related to leukocyte infiltration in human skeletal muscle . 5 . Eccentric cycling and /or muscle biopsies did not result in T cell infiltration in human skeletal muscle . Modes of stress other than eccentric cycling should therefore be evaluated as a myositis model in human . 6 . Based on results from the present study , and in the light of previously published data , it appears plausible that muscular adaptation to physical exercise occurs without preceding muscle inflammation . Nevertheless , leukocytes seem important for repair , regeneration and adaptation of human skeletal muscle Background Reductions in skeletal muscle mass and increased adiposity are key elements in the aging process and in the pathophysiology of several chronic diseases . Systemic low grade inflammation associated with obesity has been shown to accelerate the age-related decline in skeletal muscle . The aim of this investigation was to determine the effects of 12 months of progressive resistance training ( PRT ) on systemic inflammation , and whether reductions in systemic inflammation were associated with changes in body composition . We hypothesized that reductions in systemic inflammation following 12 months of PRT in older adults with type 2 diabetes would be associated with reductions in adiposity and increases in skeletal muscle mass . Methods Participants ( n = 103 ) were r and omized to receive either PRT or sham-exercise , 3 days a week for 12 months . C-reactive protein ( CRP ) was used to assess systemic inflammation . Skeletal muscle mass and total fat mass were determined using bioelectrical impedance . Results Twelve months of PRT tended to reduce CRP compared to sham exercise ( β = −0.25 , p = 0.087 ) . Using linear mixed-effects models , the hypothesized relationships between body composition adaptations and CRP changes were significantly stronger for skeletal muscle mass ( p = 0.04 ) and tended to be stronger for total fat mass ( p = 0.07 ) following PRT when compared to sham-exercise . Using univariate regression models , stratified by group allocation , reductions in CRP were associated with increases in skeletal muscle mass ( p = 0.01 ) and reductions in total fat mass ( p = 0.02 ) in the PRT group , but not in the sham-exercise group ( p = 0.87 and p = 0.32 , respectively ) . Conclusions We have shown for the first time that reductions in systemic inflammation in older adults with type 2 diabetes following PRT were associated with increases in skeletal muscle mass . Furthermore , reductions in CRP were associated with reductions in adiposity , but only when associated with PRT . Lifestyle interventions aim ed at reducing systemic inflammation in older adults with type 2 diabetes should therefore incorporate anabolic exercise such as PRT to optimize the anti-inflammatory benefits of favorable body composition adaptations CONTEXT Skeletal muscle from sedentary older adults exhibits reduced mitochondrial abundance and oxidative capacity . OBJECTIVE The primary objective was to determine whether 8 weeks of combined training ( CT ) has a more robust effect than endurance training ( ET ) or resistance training ( RT ) on mitochondrial physiology in healthy young ( 18 - 30 years ) and older ( ≥ 65 years ) adults . INTERVENTION Thirty-four young and 31 older adults were r and omly assigned to 8 weeks of ET , RT , and control/CT .  Control subjects completed 8 weeks of no exercise ( control ) followed by 8 weeks of CT  . Body composition , skeletal muscle strength , and peak oxygen uptake were measured before and after the intervention . Vastus lateralis muscle biopsy sample s were obtained before and 48 hours after the intervention . Mitochondrial physiology was evaluated by high-resolution respirometry and expression of mitochondrial proteins and transcription factors by quantitative PCR and immunoblotting . RESULTS ET and CT significantly increased oxidative capacity and expression of mitochondrial proteins and transcription factors . All training modalities improved body composition , cardiorespiratory fitness , and skeletal muscle strength . CT induced the most robust improvements in mitochondria-related outcomes and physical characteristics despite lower training volumes for the ET and RT components . Importantly , most of the adaptations to training occurred independent of age . CONCLUSION Collectively , these results demonstrate that both ET and CT increase muscle mitochondrial abundance and capacity although CT induced the most robust improvements in the outcomes measured . In conclusion , CT provides a robust exercise regimen to improve muscle mitochondrial outcomes and physical characteristics independent of age Background Chronic heart failure ( CHF ) is accompanied by an inflammatory activation which occurs both systemically and in the skeletal muscle . Exercise training has been shown to reduce the local expression of cytokines and inducible nitric oxide synthase ( iNOS ) in muscle biopsies of CHF patients . INOS-derived NO can inhibit oxidative phosphorylation and contribute to skeletal muscle dysfunction in CHF . Design To investigate the correlation between changes in local iNOS expression associated with regular exercise and changes in aerobic enzyme activities in the skeletal muscle of patients with CHF . Twenty male CHF patients [ ejection fraction 25 % ( SE 2 ) , age 54 ( SE 2 ) years ] were r and omized to a training ( n = 10 ) or a control group ( C , n = 10 ) . Methods At baseline and after 6 months skeletal muscle iNOS expression was measured by real-time polymerase chain reaction . INOS protein and protein nitrosylation were assessed by immunohistochemistry . Cytochrome c oxidase ( COX ) activity was quantified electrochemically using the Clark oxygen electrode . Results Exercise training led to a 27 % increase in cytochrome c oxidase activity [ from 21.8 ( SE 3.2 ) to 27.7 ( SE 3.5 ) nmol O2/mg per min , P=0.02 versus baseline ] . Changes in iNOS expression and iNOS protein content were inversely correlated with changes in COX-activity ( r= −0.60 , P=0.01 ; r= −0.71 , P<0.001 ) . Conclusions The inverse correlation between iNOS expression/iNOS protein content and COX-activity indicates that local anti-inflammatory effects may contribute to improved muscular oxidative metabolism Relationships among nutritional status and skeletal and respiratory muscle function were examined in 16 children with cystic fibrosis ( CF ) and mild lung disease ( FEV1 95 + /- 16 % predicted ) . Subjects were r and omly assigned to receive ( or not ) noninvasive nutritional supplementation at 25 % of normal energy recommendations for 6 mo . Skeletal muscle strength and power were similar to those of healthy children as were respiratory muscle strength and endurance . Stepwise-regression analysis indicated that changes in skeletal muscle strength and energy intake correlated significantly with growth [ weight ( kg ) = 1.90 - 0.60 ( Tanner Stage ) + 0.49 ( maximum voluntary strength ( Nm ) + 0.03 ( energy intake , % RNI ) , r = 0.76 , P < 0.05 ] , though body composition , protein biochemistry , muscle power , respiratory muscle strength , and use of dietary supplements did not . Thus , changes in skeletal muscle strength may be a functional index of changes in nutritional status in CF . Dietary supplementation per se was not associated with functional improvement BACKGROUND The improvement of exercise capacity in patients with chronic heart failure ( CHF ) by physical training has been connected with reversal of the abnormalities in muscle fiber distribution and with the reduced activity of the enzymes of oxidative metabolism in skeletal muscle . However , the change in fiber type distribution induced by training is controversial and in previous studies the activities of the rate-limiting enzymes of the metabolic pathways have not been measured . AIMS To examine the effect of dynamic training on percentage distribution of muscle fibers , on activities of the rate-limiting enzymes of the metabolic pathways and on electrophysiology in skeletal muscle . METHODS A total of 27 patients with stable CHF ( NYHA class II-III ) were r and omized to a training ( N=12 ) or a control ( N=15 ) group . The training group exercised on a bicycle ergometer for 30 min three times a week for 3 months using a load corresponding to 50 - 60 % of their peak oxygen consumption . This was followed by a 3-month training period at home according to personal instructions . The control group did not change its physical activities . We studied muscle histology and measured the activities of the rate-limiting enzymes of anaerobic glycolysis ( phosphofructokinase , PFK ) , glycogenolysis ( phosphorylase ) , citric acid cycle ( alpha-ketoglurate dehydrogenase , KGDH ) and fatty acid oxidation ( carnitinepalmitoyl transferase I and II , CPT I and II ) from biopsies of the vastus lateralis muscle at baseline and after 3 and 6 months . Muscle strength and strength endurance with surface EMG and macro EMG of the right knee extensors were also determined . RESULTS Exercise capacity , particularly submaximal , improved in the training group . The activity of PFK rose significantly but that of the other enzymes did not when compared with the change in the controls . Training had no effect on the percentage distribution of slow-twitch and fast-twitch muscle fibers or on capillary density around these fibers in skeletal muscle . Maximum voluntary force , strength endurance and the function of motor units remained unaffected . CONCLUSIONS Dynamic training results in improved exercise endurance in CHF . In skeletal muscle , the capacity of anaerobic glycolysis is increased but that of the citric acid cycle and fatty acid oxidation is not . Furthermore , the improvement in exercise endurance seems to be independent of changes in the percentage distribution of muscle fibers , capillarity or electrophysiological factors OBJECTIVE Hyperglycemia has been found to occur in children placed on cardiopulmonary bypass . Our laboratory demonstrated that hyperoxia plays a role in this hyperglycemic response and also occurs in the absence of cardiopulmonary bypass . The purpose of this study was to eluci date potential mechanisms underlying the hyperoxic-induced hyperglycemia by examining glucagon , insulin , and epinephrine , which are important in glucose regulation and skeletal and cardiac glucose transporters ( GLUT1 and GLUT4 ) , which facilitate glucose entry . METHODS Three-day-old piglets were anesthetized , intubated , and ventilated to normoxia . Animals were then r and omly allocated to either 5 hours of normoxia ( n = 4 ) or hyperoxia ( n = 6 ) . Measurements of oxygen , blood glucose , plasma glucagon , insulin , and epinephrine levels were made . Total GLUT1 and GLUT4 content in cardiac and skeletal muscle was measured using Western blotting analysis . RESULTS A sustained hyperglycemic response ( P < .001 ) was seen throughout the 5-hour ventilatory period . A significant twofold elevation in glucagon levels ( P < .001 ) and a threefold elevation ( P < .003 ) in plasma insulin levels occurred , despite no significant changes in plasma epinephrine . Total GLUT1 and GLUT4 content were significantly reduced in skeletal muscle by 66 % and 59 % , respectively , while no significant changes occurred in cardiac muscle . CONCLUSION This study demonstrates that significant elevations in glucagon and insulin and reductions in total skeletal muscle GLUT1 and GLUT4 content all contribute to hyperoxia-induced hyperglycemia seen in newborns . To optimize postoperative recovery of newborns , consideration should be given to the levels of oxygen used to avoid the potential development of insulin resistance and subsequent decrease in glucose entry 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 Objective To determine the effects of whey protein , resistance exercise , and combined protein and exercise treatment on body cell mass ( BCM ) , muscle strength , and quality of life ( QOL ) in HIV-infected women with reduced BCM . Design and setting Prospect i ve , r and omized , controlled trial at a university hospital in New York City . Methods A volunteer sample of 30 HIV-infected women were r and omized to whey protein ( PRO ) , progressive resistance exercise ( PRE ) , or combined treatment ( PRO – PRE ) for 14 weeks after a 6-week control period . The main outcome measures were body weight , BCM , skeletal muscle , fat mass , muscle strength , and QOL . Results There were no significant changes in BCM , strength , or QOL during the control period . PRO patients gained 3.6 kg ( P = 0.001 ) , and 2.5 kg fat ( P = 0.002 ) with no change in BCM ( 0.5 kg;P = 0.07 ) or skeletal muscle ( 0.6 kg;P = 0.12 ) . The PRE group increased BCM ( 0.74 kg;P = 0.03 ) and skeletal muscle ( 1.2 kg;P < 0.001 ) and decreased fat ( 1.7 kg;P = 0.02 ) . PRO – PRE increased BCM ( 0.61 kg;P = 0.01 ) without change in skeletal muscle ( 0.6 kg;P = 0.30 ) . Strength increased for both exercise groups ( range , 40.6–95.3%;P < 0.001 ) . The QOL physical activity score improved for PRE ( P = 0.02 ) and worsened for PRO ( P = 0.01 ) . Conclusions Resistance exercise significantly increased BCM , muscle mass , muscle strength , and QOL in HIV-infected women with reduced BCM . Whey protein had little effect on BCM accrual . Combined protein and exercise did not increase BCM in excess of gains achieved by exercise alone AIM Texture-modified diets ( TMD ) have significantly lower energy and protein content than normal diets . Therefore , TMD can cause malnutrition and loss of muscle mass . However , few studies have reported the relationship between TMD and decreased skeletal muscle mass . The aim of the present study was to clarify the association between TMD and decreased skeletal muscle mass . METHODS We review ed data of 188 older adult patients who were admitted to a rehabilitation hospital . TMD were defined based on the Japanese Dysphagia Diet Criteria 2013 proposed by the Japanese Society of Dysphagia Rehabilitation . The Mini Nutritional Assessment -Short Form was used to assess nutritional status ;  dual-energy X-ray absorptiometry was used to measure the skeletal muscle mass index , and the cut-off values for decreased skeletal muscle mass index were based on the Asian Working Group for Sarcopenia ; the Functional Independence Measure was used to evaluate activities of daily living . RESULTS The patients ' mean age was 80.6 ± 7.5 years , and 62 % were women . A total of 22 patients ( 11.7 % ) consumed TMD . A total of 104 patients ( 55.3 % ) had decreased skeletal muscle mass , and approximately 90 % of them consumed TMD . Decreased skeletal muscle mass index ( odds ratio 7.199 , 95 % confidence interval 1.489 - 34.805 , P ≤ 0.01 ) and Functional Independence Measure scores ( odds ratio 0.972 , 95 % confidence interval 0.952 - 0.992 , P ≤ 0.01 ) were independently related to TMD in the multivariate analysis . CONCLUSIONS The TMD group was associated with decreased skeletal muscle mass . Future , prospect i ve studies are necessary to investigate causality . Geriatr Gerontol Int 2018 ; 18 : 698 - 704 Objectives : As the catabolic state induced by septic shock together with the physical inactivity of patients lead to the rapid loss of muscle mass and impaired function , the purpose of this study was to test whether an early physical therapy during the onset of septic shock regulates catabolic signals and preserves skeletal muscle mass . Design : R and omized controlled trial . Setting : Tertiary mixed ICU . Patients : Adult patients admitted for septic shock within the first 72 hours . Interventions : Patients were assigned r and omly into two groups . The control group benefited from manual mobilization once a day . The intervention group had twice daily sessions of both manual mobilization and 30-minute passive/active cycling therapy . Measurements and Main Results : Skeletal muscle biopsies and electrophysiology testing were performed at day 1 and day 7 . Muscle biopsies were analyzed for histology and molecular components of signaling pathways regulating protein synthesis and degradation as well as inflammation markers . Hemodynamic values and patient perception were collected during each session . Twenty-one patients were included . Three died before the second muscle biopsy . Ten patients in the control and eight in the intervention group were analyzed . Markers of the catabolic ubiquitin-proteasome pathway , muscle atrophy F-box and muscle ring finger-1 messenger RNA , were reduced at day 7 only in the intervention group , but without difference between groups ( muscle atrophy F-box : –7.3 % ± 138.4 % in control vs –56.4 % ± 37.4 % in intervention group ; p = 0.23 and muscle ring finger-1 : –30.8 % ± 66.9 % in control vs –62.7 % ± 45.5 % in intervention group ; p = 0.15 ) . Muscle fiber cross-sectional area ( µm2 ) was preserved by exercise ( –25.8 % ± 21.6 % in control vs 12.4 % ± 22.5 % in intervention group ; p = 0.005 ) . Molecular regulations suggest that the excessive activation of autophagy due to septic shock was lower in the intervention group , without being suppressed . Markers of anabolism and inflammation were not modified by the intervention , which was well tolerated by the patients . Conclusions : Early physical therapy during the first week of septic shock is safe and preserves muscle fiber cross-sectional area We examined the expression of the sodium-dependent glucose co-transporter system ( hSGLT3 ) in skeletal muscle of Hispanic older adults with type 2 diabetes . Subjects ( 65±8 yr ) were  r and omized  to resistance training ( 3x/wk , n=13 ) or st and ard of care ( controls , n=5 ) for 16 weeks . Skeletal muscle hSGLT3 and GLUT4 mRNA transcript levels were determined by real time RT-PCR . hSGLT3 transcripts increased by a factor of ten following resistance training compared to control subjects ( 0.10 , P=0.03 ) . There were no differences in GLUT4 mRNA expression levels between groups . Protein expression levels of these transporters were confirmed by immunohistochemistry and Western blotting . hSGLT3 after resistance exercise was found not to be co-localized with the nicotinic acetylcholine receptor . The change in hSGLT3 transcript levels in the vastus lateralis muscle was positively correlated with glucose uptake , as measured by the change in muscle glycogen stores ( r=0.53 , P=0.02 ) ; and with exercise intensity , as measured by the change in muscle strength ( r=0.73 , P=0.001 ) . Group assignment was be the only independent predictor of hSGLT3 transcript levels , explaining 68 % of its variability ( P=0.01 ) . Our data show that hSGLT3 , but not GLTU4 , expression was enhanced in skeletal muscle after 16 weeks of resistance training . This finding suggests that hSGLT3 , an insulin-independent glucose transporter , is activated with exercise and it may play a significant role in glycemic control with muscle contraction . The hSGLT3 exact mechanism is not well understood and requires further investigation . However its functional significance regarding a reduction of glucose toxicity and improvement of insulin resistance is the subject of ongoing research Objectives To examine the effects of  Roux-en-Y gastric bypass ( RYGB ) surgery with and without laparoscopic removal of omental fat ( omentectomy )  on the temporal gene expression profiles of skeletal muscle . Design Previously reported were the whole-body metabolic effects of a r and omized , single-blinded study in patients receiving RYGB surgery stratified to receive or not receive omentectomy .  In this follow up study we report on changes in skeletal muscle gene expression in a subset of 21 patients , for whom biopsies were collected preoperatively and at either 6 months or 12 months postoperatively . Methodology /Principal Findings RNA isolated from skeletal muscle biopsies of 21 subjects ( 8 without omentectomy and 13 with omentectomy )  taken before RYGB or at 6 and 12 months postoperatively were subjected to gene expression profiling via Exon 1.0 S/T Array and Taqman Low Density Array . Robust Multichip Analysis and gene enrichment data analysis revealed 84 genes with at least a 4-fold expression difference after surgery . At 6 and 12 months the RYGB with omentectomy group displayed a greater reduction in the expression of genes associated with skeletal muscle inflammation ( ANKRD1 , CDR1 , CH25H , CXCL2 , CX3CR1 , IL8 , LBP , NFIL3 , SELE , SOCS3 , TNFAIP3 , and ZFP36 ) relative to the RYGB non-omentectomy group . Expressions of IL6 and CCL2 were decreased at all postoperative time points . There was differential expression of genes driving protein turnover ( IGFN1 , FBXW10 ) in both groups over time and increased expression of PAAF1 in the non-omentectomy group at 12 months . Evidence for the activation of skeletal muscle satellite cells was inferred from the up-regulation of HOXC10 . The elevated post-operative expression of 22 small nucleolar RNAs and the decreased expression of the transcription factors JUNB , FOS , FOSB , ATF3 MYC , EGR1 as well as the orphan nuclear receptors NR4A1 , NR4A2 , NR4A3 suggest dramatic reorganizations at both the cellular and genetic levels . Conclusions / Significance These data indicate that RYGB reduces skeletal muscle inflammation , and removal of omental fat further amplifies this response . Trial Registration Clinical Trials.gov Effects of heavy resistance exercise on serum testosterone and skeletal muscle and rogen receptor ( AR ) concentrations were examined before and after a 21-week resistance training period . Seven healthy untrained young adult men ( YT ) and ten controls ( YC ) as well as ten older men ( OT ) and eight controls ( OC ) volunteered as subjects .  Heavy resistance exercise bouts ( 5 × 10 RM leg presses ) were performed before and after the training period . Muscle biopsies were obtained before and 1h and 48 h after the resistance exercise bouts from m.vastus lateralis ( VL ) to determine cross-sectional area of muscle fibers ( fCSA ) and AR mRNA expression and protein concentrations . No changes were observed in YC and OC while resistance training led to significant increases in maximal strength of leg extensors ( 1 RM ) , fCSA and lean body mass in YT and OT . Acute increases occurred in serum testosterone concentrations due to resistance exercises but basal testosterone remained unaltered . Mean AR mRNA expression and protein concentration remained unchanged after heavy resistance exercise bouts compared to pre-values . The individual pre- to post-training changes in resting ( pre-exercise ) AR protein concentration correlated with the changes in fCSA and lean body mass in the combined group of YT and OT . Similarly , it correlated with the changes in 1 RM in YT . Although mean AR expression did not changed due to the resistance exercise training , the present findings suggest that the individual changes of AR protein concentration in skeletal muscle following resistance training may have an impact on training-induced muscular adaptations in both younger and older men OBJECTIVES The primary aims of the study were to examine the effect of resveratrol on skeletal muscle SIRT1 expression and energy expenditure in subjects with Type 2 diabetes mellitus ( T2DM ) . BACKGROUND Animal and in vivo studies indicate that resveratrol increases SIRT1 expression that stimulates PGC1α activity . Subsequent upregulation of AMPK and GLUT4 expression are associated with improved insulin sensitivity in peripheral tissues . METHODS Ten subjects with T2DM were r and omized in a double-blind fashion to receive 3 g resveratrol or placebo daily for 12 weeks . Secondary outcomes include measures of AMPK , p-AMPK and GLUT4 expression levels , energy expenditure , physical activity levels , distribution of abdominal adipose tissue and skeletal muscle fiber type composition , body weight , HbA1c , plasma lipid subfraction , adiponectin levels , and insulin sensitivity . RESULTS There was a significant increase in both SIRT1 expression ( 2.01 vs. 0.86 arbitrary units [ AU ] , p = .016 ) and p-AMPK to AMPK expression ratio ( 2.04 vs. 0.79 AU , p = .032 ) in the resveratrol group compared with the placebo group . Although the percentage of absolute change ( 8.6 vs. -13.9 % , p = .033 ) and percentage of predicted resting metabolic rate ( RMR ; 7.8 vs. -13.9 % , p = .013 ) were increased following resveratrol , there was a significant reduction in average daily activity ( -38 vs. 43.2 % , p = .028 ) and step counts ( -39.5 vs. 11.8 % , p = .047 ) when compared with placebo . CONCLUSIONS In patients with T2DM , treatment with resveratrol regulates energy expenditure through increased skeletal muscle SIRT1 and AMPK expression . These findings indicate that resveratrol may have beneficial exercise-mimetic effects in patients with T2DM 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 CONTEXT The exact relationship between the bed rest-induced loss of skeletal muscle and reductions in muscle strength and physical performance in the older individuals is still unclear . OBJECTIVE We examined the effect of 10 days of bed rest on changes in regional body composition , muscle strength , and functional status , and the relationship between these variables in older individuals . DESIGN , PARTICIPANTS , AND INTERVENTION Regional body composition was measured using dual energy x-ray absorptiometry . We also determined changes in leg strength and several indices of functional status , including walking speed . RESULTS Body weight , body mass index , and total and lower extremity lean mass decreased with bed rest . There were also significant reductions in knee extension one repetition maximum , isometric knee extension , knee extension 60 ° concentric , stair ascent time , stair ascent power , stair descent time , VO2 max , floor transfer test , 5-minute walk time , and chair st and . The overall change in total and lower extremity lean mass was also directly related to bed rest-induced reductions in one repetition maximum knee extension . CONCLUSIONS Bed rest promoted overall declines in muscle mass , muscle strength , and physical function in older individuals . The changes in lean tissue were closely correlated with the bed rest-induced decline of muscle strength Considerable evidence suggests that the loss of strength and muscle mass appear to be inevitable consequences of aging . Moreover , aging is associated with an increase in body fat . This study examined whether increased physical activity could prevent or reverse the losses of strength and skeletal muscle mass as well as the gain in  fat in older adults . Eleven men and 31 women completed a r and omized trial consisting of either a physical activity ( PA ; n = 22 ) or successful aging health educational control ( SA ; n = 20 ) group . Isokinetic knee extensor strength and computed tomography-derived midthigh skeletal muscle and adipose tissue cross-sectional areas ( CSA ) were assessed at baseline and at 12 mo following r and omization .  Total body weight and muscle CSA decreased in both groups , but these losses were not different between groups . Strength adjusted for muscle mass decreased ( -20.1 + /- 9.3 % , P < 0.05 ) in SA . The loss of strength was completely prevented in PA ( + 2.5 + /- 8.3 % ) . In addition , there was a significant increase ( 18.4 + /- 6.0 % ) in muscle fat infiltration in SA , but this gain was nearly completely prevented in PA ( 2.3 + /- 5.7 % ) . In conclusion , regular physical activity prevents both the age-associated loss of muscle strength and increase in muscle fat infiltration in older adults with moderate functional limitations Objectives : A rapid and early loss of skeletal muscle mass underlies the physical disability common amongst survivors of critical illness . However , skeletal muscle function depends not only on its quantity but its quality , which may be adversely affected . We set out to characterise the changes in macroscopic muscle echogenicity and fascial characteristics that occur early in critical illness , and to relate these to microscopic histologically defined myofibre necrosis and fascial pathology . Design and Setting : Prospect i ve two center observational study . Patients : Thirty subjects comprising a subgroup of patients recruited to the Musculoskeletal Ultrasound in Critical Illness : Longitudinal Evaluation ( MUSCLE ) study . Measurements and Main Results : Comparisons were made between sequential Vastus Lateralis histological specimens and ultrasound assessment of Rectus Femoris echogenicity . Change in muscle echogenicity was greater in patients who developed muscle necrosis ( n = 15 ) than in those who did not ( 8.2 % [ 95 % CI , –5.3 to 21.7 ] vs –15.0 % [ 95 % CI , –28.9 to –1.09 ] ; p = 0.016 ) . The area under receiver operator curve for ultrasound echogenicity ’s prediction of myofiber necrosis was 0.74 ( 95 % CI , 0.565 to 0.919 ; p = 0.024 ) increasing to 0.85 ( 95 % CI , 0.703 to –0.995 ; p = 0.003 ) with the removal of those with potential iatrogenic muscle damage . Fasciitis was observed in 18 of 30 biopsies ( 60 % ) . Conclusions : Myofiber necrosis and fascial inflammation can be detected noninvasively using ultrasound in the critically ill . Fasciitis precedes and frequently accompanies muscle necrosis . These findings may have functional implication s for survivors of critical illness & NA ; Ischemic preconditioning of the myocardium with repeated brief periods of ischemia and reperfusion prior to prolonged ischemia significantly reduces subsequent myocardial infa rct ion . Following ischemic preconditioning , two “ windows of opportunity ” ( early and late ) exist , during which time prolonged ischemia can occur with reduced infa rct ion size . The early window occurs at approximately 4 hours and the late window at 24 hours following ischemic preconditioning of the myocardium . We investigated if ischemic preconditioning of skeletal muscle prior to flap creation improved subsequent flap survival and perfusion immediately or 24 hours following ischemic preconditioning . Currently , no data exist on the utilization of ischemic preconditioning in this fashion . The animal model used was the latissimus dorsi muscle of adult male Sprague‐Dawley rats . Animals were assigned to three groups , and the right or left latissimus dorsi muscle was chosen r and omly in each animal . Group 1 ( n = 12 ) was the control group , in which the entire latissimus dorsi muscle was elevated acutely without ischemic preconditioning . Group 2 ( n = 8) investigated the effects of ischemic preconditioning in the early window . In this group , the latissimus dorsi muscle was elevated immediately following preconditioning . Group 3 ( n = 8) investigated the effects of ischemic preconditioning in the late window , with elevation of the latissimus dorsi muscle 24 hours following ischemic preconditioning . The preconditioning regimen used in groups 2 and 3 was two 30‐minute episodes of normothermic global ischemia with intervening 10‐minute episodes of reperfusion . Latissimus dorsi muscle ischemia was created by occlusion of the thoracodorsal artery and vein and the intercostal perforators , after isolation of the muscle on these vessels . Muscle perfusion was assessed by a laser‐Doppler perfusion imager . One week after flap elevation , muscle necrosis was quantified in all groups by means of computer‐assisted digital planimetry . Our results show that ischemic preconditioning result ed in a significant reduction ( p < 0.05 ) in muscle‐flap necrosis immediately and 24 hours following ischemic preconditioning . Perfusion changes after flap elevation were similar among the three groups . Ischemic preconditioning of skeletal muscle prior to flap creation significantly reduces subsequent muscle‐flap necrosis caused by the ischemia of flap creation immediately and 24 hours following ischemic preconditioning . Further elaboration of the mechanisms of ischemic preconditioning may allow pharmacologic preconditioning to be used in the augmentation of skeletal muscle‐flap survival in the clinical setting . ( Plast . Reconstr . Surg . 100 : 58 , 1997 . BACKGROUND Trials of testosterone therapy in aging men have demonstrated increases in fat-free mass ( FFM ) and skeletal muscle and decreases in fat mass ( FM ) but have not reported the impact of baseline body composition . OBJECTIVE The objective of the study was to determine the effect , in nonobese aging men with symptoms of and rogen deficiency and low-normal serum testosterone levels , of testosterone therapy on total and regional body composition and hormonal and metabolic indices . METHODS Sixty healthy but symptomatic , nonobese men aged 55 yr or older with total testosterone ( TT ) levels less than 15 nm were r and omized to transdermal testosterone patches or placebo for 52 wk . Body composition , by dual-energy x-ray absorptiometry ( FM , FFM , skeletal muscle ) and magnetic resonance imaging ( abdominal sc and visceral adipose tissue , thigh skeletal muscle , and intermuscular fat ) and hormonal and metabolic parameters were measured at wk 0 and 52 . RESULTS Serum TT increased by 30 % ( P = 0.01 ) , and LH decreased by 50 % ( P < 0.001 ) . Relative to placebo , total body FFM ( P = 0.03 ) and skeletal muscle ( P = 0.008 ) were increased and thigh skeletal muscle loss was prevented ( P = 0.045 ) with testosterone therapy and visceral fat accumulation decreased ( P = 0.001 ) without change in total body or abdominal sc FM ; change in visceral fat was correlated with change in TT levels ( r2 = 0.36 ; P = 0.014 ) . There was a trend to increasing total and low-density lipoprotein cholesterol with placebo . CONCLUSION Testosterone therapy , relative to placebo , selectively lessened visceral fat accumulation without change in total body FM and increased total body FFM and total body and thigh skeletal muscle mass . Further studies are needed to determine the impact of these body compositional changes on markers of metabolic and cardiovascular risk OBJECTIVE To establish rates of skeletal mineralization in children and adolescents , and to identify factors that influence these rates . DESIGN Three-year observational study . SETTING University hospital . SUBJECTS Ninety white children , aged 6 to 14 years . MEASUREMENTS Bone mineral density of the radius , spine , and hip was measured at baseline and 3 years later .  Physical activity  was assessed by question naires at 6-month intervals and dietary calcium intake by diet diary 1 day per month for 36 months . Sexual maturation ( Tanner stage ) was determined by an endocrinologist at 6-month intervals , as necessary to classify children as prepubertal , peripubertal , or postpubertal . RESULTS Skeletal mineralization accelerated markedly at puberty in the spine ( 0.077 vs 0.027 gm/cm2 per year , peripubertal vs prepubertal ) and greater trochanter ( 0.050 vs 0.027 gm/cm2 per year ) , less markedly in the femoral neck ( 0.047 vs 0.030 gm/cm2 per year ) , and only slightly in the radius . Nearly one third ( 15 gm ) of the total skeletal mineral in the lumbar spine of adult women ( approximately 52 gm ) was accumulated in the 3 years around the onset of puberty . Increases in height and weight were the strongest correlates of skeletal mineralization : weight changes were more strongly correlated with trabecular bone sites and changes in height with cortical bone sites . Increases in calf muscle area were strongly associated with mineralization , particularly in peripubertal children , and physical activity was associated with more rapid mineralization in prepubertal children . CONCLUSIONS Puberty has varying effects on skeletal mineralization depending on skeletal site ; trabecular bone is apparently more sensitive to changing hormone concentrations . Physical activity and normal growth are also positively associated with skeletal mineralization , also depending on skeletal site and sexual maturation BACKGROUND It is still unknown whether the fatty acid composition of human skeletal muscle lipids is directly influenced by the fat composition of the diet . OBJECTIVE We investigated whether the fatty acid composition of the diet is reflected in the fatty acid profile of skeletal muscle phospholipids and triacylglycerols . DESIGN Thirty-two healthy adults ( 25 men and 7 women ) included in a larger controlled , multicenter dietary study were r and omly assigned to diets containing a high proportion of either saturated fatty acids ( SFAs ) [ total fat , 36 % of energy ; SFAs , 18 % of energy ; monounsaturated fatty acids ( MUFAs ) , 10 % of energy ] or MUFAs ( total fat , 35 % of energy ; SFAs , 9 % of energy ; MUFAs , 19 % of energy ) for 3 mo . Within each diet group , there was a second r and om assignment to supplementation with fish oil capsules [ containing 3.6 g n-3 fatty acids/d ; 2.4 g eicosapentaenoic acid ( 20:5n-3 ) and docosahexaenoic acid ( 22:6n-3 ) ] or placebo . A muscle biopsy sample was taken from the vastus lateralis muscle after the diet period . Parallel analyses of diet and supplementation effects were performed . RESULTS The proportions of myristic ( 14:0 ) , pentadecanoic ( 15:0 ) , heptadecanoic ( 17:0 ) , and palmitoleic ( 16:1n-7 ) acids in the skeletal muscle phospholipids were higher and the proportion of oleic acid ( 18:1n-9 ) was lower in the SFA group than in the MUFA group . The proportion of total n-3 fatty acids in the muscle phospholipids was approximately 2.5 times higher , with a 5 times higher proportion of eicosapentaenoic acid ( 20:5n-3 ) , in subjects supplemented with n-3 fatty acids than in those given placebo . Similar differences were observed in the skeletal muscle triacylglycerols . CONCLUSION The fatty acid composition of skeletal muscle lipids reflects the fatty acid composition of the diet in healthy men and women
Inflammation appeared to be associated with greater loss of muscle strength .
There was inconclusive evidence that the level of physical activity affects change in skeletal muscle .
In regard to the effect of interventions , only exercise interventions were consistently associated with improved skeletal muscle outcomes .
CONCLUSIONS Adult patients who undergo an unplanned hospital admission may experience a small reduction in knee extension strength and mid-arm muscle mass .
OBJECTIVES The primary objective of the review was to describe change that occurs in skeletal muscle during periods of unplanned hospitalisation in adult patients .
The secondary objective was to examine the relationship between both physical activity and inflammation with the change in skeletal muscle .
A further objective was to investigate the effect of interventions on change in skeletal muscle during periods of unplanned hospitalisation .