Effect of Structured Physical Activity and Nutritional Supplementation on Physical Function in Mobility-Limited Older Adults: Results from the VIVE2 Randomized Trial

Protein-enriched soup and weekly exercise improve muscle health: A randomized trial in mid-to-old age with inadequate protein intake

BACKGROUND

Prior research has highlighted the synergistic impact of protein supplementation on muscle function post-exercise in adults; however, evidence supporting the combined effects were less robust and inconsistent on those with protein insufficiency. This investigation aims to explore efficacy of protein-enriched soup coupled with exercise on muscle health and metabolism in middle-aged and older adults with suboptimal protein intake.

METHODS

An open-label, 12-week, randomized controlled trial involving participants with insufficient protein intake (<1.0 g/kg/day) was done. The intervention group consumed protein-enriched soup (24-30 g protein daily) and 1-h weekly exercise, while controls received health education. Assessments included laboratory tests, functional assessments, and body composition.

RESULTS

In this trial, 97 out of 100 randomized participants (mean age: 64.65 ± 4.84 years, 81.8% female) completed the study (47 in intervention group and 50 in control group). Compared results of baselines, at 1 and 3 months of intervention, significant improvements in waist circumference (83.48 ± 10.22 vs. 82.5 ± 9.88 vs. 82.37 ± 9.42 cm, P for trend = 0.046), 6-min walking distance (525.65 ± 58.46 vs. 534.47 ± 51.87 vs. 552.02 ± 57.66 m, P for trend = 0.001), five-time sit-to-stand time (7.63 ± 1.63 vs. 6.81 ± 1.8 vs. 6.4 ± 1.42 s, P for trend <0.001), grip strength (26.74 ± 6.54 vs. 27.53 ± 6.99 vs. 28.52 ± 7.09 kg, P for trend <0.001), and MNA score (26.8 ± 2.14 vs. 27.73 ± 1.74 vs. 27.55 ± 1.72, P for trend <0.001) were discerned within the intervention group. The intervention demonstrated a significant reduction in serum triglyceride (105.32 ± 49.84 vs. 101.36 ± 42.58 vs. 93.43 ± 41.49 mg/dL, P for trend = 0.023), increased HDL-C (60.04 ± 16.21 vs. 60 ± 17.37 vs. 62.55 ± 18.27 mg/dL, P for trend = 0.02), and DHEA-S levels (97.11 ± 54.39 vs. 103.39 ± 56.75 vs. 106.83 ± 60.56 μg/dL, P for trend = 0.002). Serum myostatin did not differ in both groups, but serum leptin levels significantly increased (9118.88 ± 5811.68 vs. 11508.97 ± 7151.08 vs. 11220.80 ± 7190.71 pg/mL, P for trend = 0.016) in controls. The intervention group showed greater improvements in 6 min walking distance (β = 0.71, 95% CI: 6.88 to 40.79, P = 0.006), five-time sit-to-stand test (β = -0.87, 95% CI: -1.59 to -0.15, P = 0.017), MNA score (β = 0.96, 95% CI: 0.20 to 1.71, P = 0.013), serum triglycerides (β = -15.01, 95% CI: -27.83 to -2.20, P = 0.022), LDL-C (β = -9.23, 95% CI: -16.98 to -1.47, P = 0.020), and DHEA-S levels (β = 9.98, 95% CI: 0.45 to 19.51, P = 0.04) than controls.

CONCLUSIONS

Protein-enriched soup with weekly exercise over 12 weeks significantly improved physical performance, lipid profile, and DHEA-S levels among middle-aged and older adults with inadequate protein intake, while studies assessing long-term benefits of the intervention are needed.

Prevention and Treatment of Malnutrition in Older Adults Living in Long-Term Care or the Community: an Evidence-based Nutrition Practice Guideline

Malnutrition in older adults can decrease quality of life and increase risk of morbidities and mortality. Accurate and timely identification of malnutrition, as well as subsequent implementation of effective interventions, are essential to decrease poor outcomes associated with malnutrition in older adults. The Academy of Nutrition and Dietetics Evidence Analysis Center conducted a systematic review of the literature to develop an evidence-based nutrition practice guideline for the prevention and treatment of malnutrition in older adults. The objective of this guideline was to provide evidence-based recommendations to identify, prevent, or treat protein-energy malnutrition in older adults (mean age ≥65 years) living in long-term care and community settings. This guideline provides 11 nutrition recommendations to inform shared decision making among dietitians, members of the health care team, family members or caregivers, and older adults living in long-term care or the community to prevent or treat malnutrition. Topics include dietitian effectiveness, nutrition assessment tools, oral nutrition supplements, food fortification, and home-delivered and congregate meals. Guideline implementation should include consideration of the importance of comprehensive individualized nutrition care for older adults. Future research is needed to address gaps that were identified related to the validity, reliability, and feasibility of nutrition assessment tools, as well as the effectiveness of dietitian interventions on outcomes of interest in older adults living in long-term care and the community.

A comparative intervention trial of deer milk and an oral nutritional supplement efficacy for improving older adults' nutritional status, muscle mass and physical performance

OBJECTIVES

To compare the effectiveness of deer milk (DM) for improving nutritional status, muscle mass and physical performance with that of a commercially available oral nutritional supplement (ONS) in older women.

METHODS

This study was an 11-week randomised, double-blind, parallel group study. Healthy women (N = 120) aged 65-80 years, the majority having a body mass index (BMI) < 25 kg/m2 were recruited. The women were randomly assigned to either 200 ml DM or a commercial ONS for 11 weeks. Data on habitual macronutrient intake, nutritional status (Mini Nutrition Assessment-Short Form, MNA-SF; ≤7 malnourished, 8-11 at risk of malnutrition, ≥12 normal nutrition), anthropometrics/body composition, and physical performance were collected. Blood samples were collected for metabolic markers.

RESULTS

102 women (DM 45, ONS 57) completed the study, of whom 29% had a dietary protein intake of <1 g/kg body weight per day, and 38% at risk of malnutrition. There were no between group differences in percentage change in MNA-SF score and body composition (P > 0.05), but a trend for a difference in handgrip strength (DM 11.7 ± 49.8% vs. ONS -2.42 ± 17.9%, P = 0.06). Further exploratory analysis showed that there was a trend for a between group difference in percentage change in MNA-SF score, favoring DM (DM 7.72 + 13.0% vs. ONS 0.63 + 9.25%, P = 0.06) only in women at risk of malnutrition. There was also a between group difference in percentage change in muscle mass (DM 1.68 ± 2.77% vs. ONS -0.18 ± 2.81%, P = 0.02) in women with BMI ≥25 kg/m2 and in handgrip strength (DM 10.6 ± 23.6% vs. ONS -5.03 ± 18.1%, P < 0.01) in women with BMI<25 kg/m2. Total cholesterol, LDL and LDL:HDL ratio did not change over time (P > 0.05), but there was a between group difference in percentage change in these markers (total cholesterol: DM 3.01 ± 6.97% vs. ONS -2.65 ± 9.92%, P < 0.01; LDL: DM 4.22 ± 14.9% vs. ONS -6.05 ± 17.6%, P < 0.01; LDL:HDL ratio: DM: 2.27 ± 16.4% vs. ONS: -5.78 ± 18.2%, P = 0.02).

CONCLUSION

Baseline nutritional status and BMI may modulate nutritional status, muscle mass and physical performance response to DM (as compared with ONS), suggesting DM may improve nutritional status and physical performance in women at risk of malnutrition and/or with lower BMI, and improve muscle mass in women with a higher BMI. The study was registered with the Australian New Zealand Clinical Trial Registry ACTRN12621000650897p.

A systematic review and meta-analysis of the effects of community use of oral nutritional supplements on clinical outcomes

The impact of oral nutritional supplements (ONS) on patients with complications (disease related morbidity) requires further exploration. This systematic review included 44 randomised controlled trials (RCT) (29 RCT surgical, 15 RCT medical patients) examining the effect of ONS in community settings on the incidence of complications (n = 716, mean age 67 years, range 35-87). ONS (mean intake 588 kcal/day, range 125-1750; protein 22 g/day, range 0-54; mean energy from protein 22 %, range 0-54) were prescribed for a mean 74 days, range 5-365. Most RCT (77 %) reported fewer complications in the ONS group versus control. Meta-analysis (39 RCT) showed ONS consumption reduced complications including infections, pressure ulcers, wound and fracture healing (OR 0.68, 95 % CI 0.59,0.79; p<0.001). Results showed reductions when ONS were used in hospital and community settings (OR 0.72, 95 % CI 0.59,0.87; p = 0.001) or just in the community (OR 0.65, 95 % CI 0.52, 0.80; p<0.001). Reductions in complications were only seen with high ONS adherence ≥ 80 % (OR 0.63, 95 % CI 0.48,0.83; p = 0.001) and ready-to-drink ONS (OR 0.69, 95 % CI 0.60,0.81; p<0.001). This systematic review and meta-analysis show community-based use of ONS in addition to the diet substantially reduces the incidence of complications. The diversity of ONS, patient populations and complication outcomes within the trials included in this review mean further research is warranted.

Chinese expert consensus on prevention and intervention for the elderly with malnutrition (2022)

Malnutrition is a state of altered body composition and body cell mass due to inadequate intake or utilization of energy or nutrients, leading to physical and mental dysfunction and impaired clinical outcomes. As one of the most common geriatric syndromes, malnutrition in the elderly is a significant risk factor for poor clinical outcomes, causing a massive burden on medical resources and society. The risk factors for malnutrition in the elderly are diverse and include demographics, chronic diseases, and psychosocial factors. Presently, recommendations for the prevention and intervention of malnutrition in the elderly are not clear or consistent in China. This consensus is based on the latest global evidence and multiregional clinical experience in China, which aims to standardize the prevention and intervention of malnutrition in the elderly in China and improve the efficacy of clinical practice and the prognosis of elderly patients.

Functional improvements to 6 months of physical activity are not related to changes in size or density of multiple lower-extremity muscles in mobility-limited older individuals

Older adults are encouraged to engage in multicomponent physical activity, which includes aerobic and muscle-strengthening activities. The current work is an extension of the Vitality, Independence, and Vigor in the Elderly 2 (VIVE2) study - a 6-month multicenter, randomized, placebo-controlled trial of physical activity and nutritional supplementation in community dwelling 70-year-old seniors. Here, we examined whether the magnitude of changes in muscle size and quality differed between major lower-extremity muscle groups and related these changes to functional outcomes. We also examined whether daily vitamin-D-enriched protein supplementation could augment the response to structured physical activity. Forty-nine men and women (77 ± 5 yrs) performed brisk walking, muscle-strengthening exercises for the lower limbs, and balance training 3 times weekly for 6 months. Participants were randomized to daily intake of a nutritional supplement (20 g whey protein + 800 IU vitamin D), or a placebo. Muscle cross-sectional area (CSA) and radiological attenuation (RA) were assessed in 8 different muscle groups using single-slice CT scans of the hip, thigh, and calf at baseline and after the intervention. Walking speed and performance in the Short Physical Performance Battery (SPPB) were also measured. For both CSA and RA, there were muscle group × time interactions (P < 0.01). Significant increases in CSA were observed in 2 of the 8 muscles studied, namely the knee extensors (1.9%) and the hip adductors (2.8%). For RA, increases were observed in 4 of 8 muscle groups, namely the hip flexors (1.1 HU), hip adductors (0.9 HU), knee extensors (1.2 HU), and ankle dorsiflexors (0.8 HU). No additive effect of nutritional supplementation was observed. While walking speed (13%) and SPPB performance (38%) improved markedly, multivariate analysis showed that these changes were not associated with the changes in muscle CSA and RA after the intervention. We conclude that this type of multicomponent physical activity program results in significant improvements in physical function despite relatively small changes in muscle size and quality of some, but not all, of the measured lower extremity muscles involved in locomotion.

Effects of resistance exercise and whey protein supplementation on skeletal muscle strength, mass, physical function, and hormonal and inflammatory biomarkers in healthy active older men: a randomised, double-blind, placebo-controlled trial

PURPOSE

To determine the individual and combined effects of 12 weeks of resistance exercise (RE) and whey protein supplementation on skeletal muscle strength (primary outcome), mass and physical function, and hormonal and inflammatory biomarkers in older adults.

METHODS

Thirty-six healthy older men [(mean±SE) age: 67±1 y; BMI: 25.5±0.4 kg/m²] were randomised to either control (CON; n=9), whey protein (PRO; n=9), RE+control (EX+CON; n=9), or RE+whey protein (EX+PRO; n=9) in a double-blinded fashion. Whole-body RE (2 sets of 8 repetitions and 1 set to volitional failure at 80% 1RM) was performed twice weekly. Supplements (PRO, 25 g whey protein isolate; CON, 23.75 g maltodextrin) were consumed twice daily.

RESULTS

EX+CON and EX+PRO increased leg extension (+19±3 kg and +20±3 kg, respectively) and leg press 1RM (+27±3 kg and +39±2 kg, respectively) greater than the CON and PRO groups (P<0.001, Cohen's d=1.50-1.90). RE (EX+CON and EX+PRO groups pooled) also increased fat-free mass (FFM) (+0.9±0.3 kg) and 6-min walk test distance (+21±5 m) and decreased fat mass (-0.4±0.4 kg), and interleukin-6 (-1.0±0.4 pg/mL) and tumor necrosis factor-alpha concentration (-0.7±0.3 pg/mL) greater than non-exercise (CON and PRO groups pooled; P<0.05, Cohen's f=0.37-0.45). Whey protein supplementation (PRO and EX+PRO groups pooled) increased 4-m gait speed greater than control (CON and EX+CON groups pooled) (+0.08±0.03 m/s; P=0.007, f=0.51).

CONCLUSION

RE increased muscle strength, FFM and physical function, and decreased markers of systemic inflammation in healthy active older men. Whey protein supplementation alone increased gait speed. No synergistic effects were observed. This study was registered at clinicaltrials.gov as NCT03299972.

Does the combination of resistance training and a nutritional intervention have a synergic effect on muscle mass, strength, and physical function in older adults? A systematic review and meta-analysis

BACKGROUND

Health-promoting interventions are important for preventing frailty and sarcopenia in older adults. However, there is limited evidence that nutritional interventions yield additional effects when combined with resistance training. This systematic review and meta-analysis aimed to compare the effectiveness of nutritional interventions with resistance training and that of resistance training alone.

METHODS

Randomized controlled trials published in peer-reviewed journals prior to July 2020 were retrieved from databases and other sources. The articles were screened according to the inclusion and exclusion criteria. The methodological quality of the included studies was assessed using Cochrane's risk of bias tool 2. A meta-analysis was performed using the RevMan 5.4 program and STATA 16 program.

RESULTS

A total of 22 studies were included in the meta-analysis. The results of the meta-analysis showed no significant differences between groups in muscle mass, muscle strength, or physical functional performance. In the subgroup analysis regarding the types of nutritional interventions, creatine showed significant effects on lean body mass (n = 4, MD 2.61, 95% CI 0.51 to 4.72). Regarding the other subgroup analyses, there were no significant differences in appendicular skeletal muscle mass (p = .43), hand grip strength (p = .73), knee extension strength (p = .09), chair stand test results (p = .31), or timed up-and-go test results (p = .31). In the meta-regression, moderators such as the mean age of subjects and duration of interventions were not associated with outcome variables.

CONCLUSIONS

This meta-analysis showed that nutritional interventions with resistance training have no additional effect on body composition, muscle strength, or physical function. Only creatine showed synergistic effects with resistance training on muscle mass.

TRIAL REGISTRATION

CRD42021224843 .

A Whole-Grain Diet Increases Whole-Body Protein Balance Compared with a Macronutrient-Matched Refined-Grain Diet

BACKGROUND

There are limited data from randomized control trials to support or refute the contention that whole-grains can enhance protein metabolism in humans.

OBJECTIVES

To examine: 1) the clinical effects of a whole-grain diet on whole-body protein turnover; 2) the cellular effects of whole-grains on protein synthesis in skeletal muscle cells; and 3) the population effects of whole-grain intake on age-related muscle loss.

METHODS

Adults with overweight/obesity (n = 14; age = 40 ± 7 y; BMI = 33 ± 5 kg/m2) were recruited into a crossover, randomized controlled trial (NCT01411540) in which isocaloric, macronutrient-matched whole-grain and refined-grain diets were fully provisioned for two 8-wk periods. Diets differed only in the presence of whole-grains (50 g/1000 kcal). Whole-body protein kinetics were assessed at baseline and after each diet in the fasted-state (13C-leucine) and integrated over 24 h (15N-glycine). In vitro studies using C2C12 cells assessed global protein synthesis by surface sensing of translation and anabolic signaling by Western blot. Complementary epidemiological assessments using the NHANES database assessed the effect of whole-grain intake on muscle function assessed by gait speed in older adults (n = 2783).

RESULTS

Integrated 24-h net protein balance was 3-fold higher on a whole-grain diet compared with a refined-grain diet (P = 0.04). A whole-grain wheat extract increased submaximal rates of global protein synthesis (27%, P < 0.05) in vitro. In a large sample of older adults, whole-grain intake was associated with greater muscle function (OR = 0.92; 95% CI: 0.86, 0.98).

CONCLUSIONS

Consuming 50 g/1000 kcal whole-grains per day promotes greater protein turnover and enhances net protein balance in adults. Whole-grains impact skeletal muscle at the cellular level, and are associated with greater muscle function in older adults. Collectively, these data point to a new mechanism whereby whole-grain consumption favorably enhances protein turnover and improves health outcomes.This clinical trial is registered on clinicaltrials.gov (identifier: NCT01411540).

Effects of branched-chain amino acid-rich supplementation on EWGSOP2 criteria for sarcopenia in older adults: a systematic review and meta-analysis

PURPOSE

According to criteria recommended by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), we analyzed the effects of branched-chain amino acid (BCAA)-rich supplements on muscle strength, muscle mass, and physical performance in older people.

METHODS

We searched PubMed, Embase, Cochrane Library, and CINAHL from inception until March 2021. Randomized controlled trials that examined the effect of BCAA-rich supplements on older people were included. Random-effects meta-analyses and sensitivity analyses were performed. Subgroup analyses were stratified by participant and supplementation characteristics. Meta-regression analyses were performed to examine the effect of continuous variables.

RESULTS

Thirty-five studies were included in this meta-analysis. Quality assessment revealed that 14 of 35 RCTs had some potential bias. The overall standardized mean difference (SMD) in muscle strength, muscle mass, and physical performance between the supplement and control groups was 0.35 (95% CI = [0.15, 0.55], P = 0.0007), 0.25 (95% CI = [0.10, 0.40], P = 0.0008), and 0.29 (95% CI = [0.00, 0.57], P = 0.05), respectively. Subgroup analysis revealed that essential amino acid supplementation improved handgrip strength more significantly than whey protein supplementation in older people. Meta-regression analysis revealed a significant linear relationship between improvements in handgrip strength and body mass index.

CONCLUSIONS

BCAA-rich supplementation by older people may have beneficial effects on muscle mass and strength. However, the included studies had high heterogeneity, and the results must be interpreted with caution.

PROSPERO REGISTRATION NUMBER

CRD42020206674.

Identifying and Managing Malnutrition, Frailty and Sarcopenia in the Community: A Narrative Review

Malnutrition, frailty and sarcopenia are becoming increasingly prevalent among community-dwelling older adults; yet are often unidentified and untreated in community settings. There is an urgent need for community-based healthcare professionals (HCPs) from all disciplines, including medicine, nursing and allied health, to be aware of, and to be able to recognise and appropriately manage these conditions. This paper provides a comprehensive overview of malnutrition, frailty and sarcopenia in the community, including their definitions, prevalence, impacts and causes/risk factors; and guidance on how these conditions may be identified and managed by HCPs in the community. A detailed description of the care process, including screening and referral, assessment and diagnosis, intervention, and monitoring and evaluation, relevant to the community context, is also provided. Further research exploring the barriers/enablers to delivering high-quality nutrition care to older community-dwelling adults who are malnourished, frail or sarcopenic is recommended, to inform the development of specific guidance for HCPs in identifying and managing these conditions in the community.

The Effects of Lifestyle and Diet on Gut Microbiota Composition, Inflammation and Muscle Performance in Our Aging Society

Living longer is associated with an increased risk of chronic diseases, including impairments of the musculoskeletal and immune system as well as metabolic disorders and certain cancers, each of which can negatively affect the relationship between host and microbiota up to the occurrence of dysbiosis. On the other hand, lifestyle factors, including regular physical exercise and a healthy diet, can affect skeletal muscle and immune aging positively at all ages. Accordingly, health benefits could partly depend on the effect of such interventions that influence the biodiversity and functionality of intestinal microbiota. In the present review, we first discuss the physiological effects of aging on the gut microbiota, immune system, and skeletal muscle. Secondly, we describe human epidemiological evidence about the associations between physical activity and fitness and the gut microbiota composition in older adults. The third part highlights the relevance and restorative mechanisms of immune protection through physical activity and specific exercise interventions during aging. Fourth, we present important research findings on the effects of exercise and protein as well as other nutrients on skeletal muscle performance in older adults. Finally, we provide nutritional recommendations to prevent malnutrition and support healthy active aging with a focus on gut microbiota. Key nutrition-related concerns include the need for adequate energy and protein intake for preventing low muscle mass and a higher demand for specific nutrients (e.g., dietary fiber, polyphenols and polyunsaturated fatty acids) that can modify the composition, diversity, and metabolic capacity of the gut microbiota, and may thus provide a practical means of enhancing gut and systemic immune function.

Effects of Exercise Dose and Detraining Duration on Mobility at Late Midlife: A Randomized Clinical Trial

BACKGROUND

Office workers near retirement tend to be sedentary and can be prone to mobility limitations and diseases. We examined the dose effects of exergaming volume and duration of detraining on motor and cognitive function in office workers at late midlife to reduce sedentariness and mobility limitations.

METHODS

In an assessor-blinded randomized trial, 160 workers aged 55-65 years performed physically active video games in a nonimmersive form of virtual reality (exergaming) in small, supervised groups for 1 h, 1×, 2×, or 3×/week for 8 weeks followed by detraining for 8 and 16 weeks. Exergaming comprises high-intensity, full-body sensorimotor coordination, balance, endurance, and strengthening exercises. The primary outcome was the 6-minute walk test (6MWT), and secondary outcomes were body mass, self-reported physical activity, sleep quality, Berg Balance Scale, Short Physical Performance Battery, fast gait speed, dynamic balance, heart rate recovery after step test, and 6 cognitive tests.

RESULTS

The 3 groups were not different in any of the outcomes at baseline (all p > 0.05). The outcomes were stable and had acceptable reliability (intraclass correlation coefficients ≥0.334) over an 8-week control period. Training produced an inverted U-shaped dose response of no (1×), most (2×), and medium (3×/week) effects of exergaming volume in most motor and selected cognitive outcomes. The distance walked in the 6MWT (primary outcome) increased most (94 m, 19%, p < 0.05), medium (57 m, 12%, p < 0.05), and least (4 m, 1%) after exergaming 2×, 3×, or 0× (control) (all different p < 0.05). The highest responders tended to retain the exercise effects over 8 weeks of detraining, independent of training volume. This maintenance effect was less consistent after 16 weeks of detraining.

CONCLUSION

Less was more during training and lasted longer after detraining. A medium dose volume of exergaming produced the largest clinically meaningful improvements in mobility and selected cognitive tests in 60-year-old office workers with mild mobility limitations and intact cognition.

Interaction Between Vitamin D and Interleukin 6 on Slow Gait Speed: 6-Year Follow-up Data of Older Adults From InCHIANTI

BACKGROUND

Whereas the independent effects of biomarkers, including 25-hydroxy vitamin D (25(OH)D), insulin-like growth factor 1, C-reactive protein, and interleukin 6 (IL-6), on gait speed in older adults have been evaluated, their joint effects on gait speed are not well understood.

METHODS

Study subjects aged at least 65 at baseline (N = 970) were enrolled in the population-based Invecchiare in Chianti (InCHIANTI) study from 1998 to 2000 and were followed up at 3 and 6 years. All above biomarkers and gait speed data were measured at each of the three time points. Using a generalized estimating equation approach, we determined if slow gait speed (<0.8 m/s) was associated with the biomarkers. Further investigation was conducted for interactions between high IL-6 (≥.87 pg/mL) and other biomarkers focusing on low 25(OH)D (<20 ng/mL).

RESULTS

After controlling for other biomarkers and potential confounders, IL-6 emerged as the only biomarker independently associated with gait speed. The association between high IL-6 and slow gait speed was enhanced by low 25(OH)D, with significant interaction between high IL-6 and low 25(OH)D (p = .038). The odds ratio of slow gait speed for low 25(OH)D and high IL-6 was 1.63 (95% confidence interval [CI]: 1.15, 2.32) compared with the reference groups with both biomarker levels at the other ends.

CONCLUSION

The association of low vitamin D with slow gait speed statistically interacts with high IL-6. Coexisting vitamin D insufficiency and inflammation may provide a better biomarker for identifying those at risk of developing impairments in gait speed than either factor alone.

The effect of vitamin D plus protein supplementation on sarcopenia: A systematic review and meta-analysis of randomized controlled trials

PURPOSE

The exact effect of vitamin D supplementation, either as monotherapy or in combination with protein, on musculoskeletal health in patients with sarcopenia is currently unknown. This study aimed to determine the effect of vitamin D alone or with protein supplementation on muscle strength, mass, and performance in this population.

METHODS

A comprehensive search was conducted in Medline, Cochrane Central and Scopus databases, up to March 31^st, 2020. Data were expressed as standardized mean difference (SMD) with 95 % confidence intervals (CI). I² index was employed for heterogeneity.

RESULTS

The initial search identified 1164 studies, eight of which met the eligibility criteria for qualitative and quantitative analysis, yielding a total of 776 patients. Vitamin D (100-1600 IU/day) plus protein (10-44 g/day) supplementation exhibited a beneficial effect on muscle strength, as demonstrated by an improvement in handgrip strength (SMD 0.38 ± 0.07, 95 % CI 0.18-0.47, p = 0.04; I² 76.2 %) and a decrease in the sit-to-stand time (SMD 0.25 ± 0.09, 95 % CI 0.06-0.43, p = 0.007; I² 0%) compared with placebo. However, the effect on muscle mass, assessed by skeletal muscle index, was marginally non-significant (SMD 0.25 ± 0.13, 95 % CI -0.006-0.51, p = 0.05; I² 0%). No effect on appendicular skeletal muscle mass or muscle performance (assessed by walking speed) was observed with vitamin D plus protein.

CONCLUSIONS

Vitamin D supplementation, combined with protein, improves muscle strength in patients with sarcopenia, but has no effect on muscle mass or performance.

A Randomized Controlled Pilot Exercise and Protein Effectiveness Supplementation Study (EXPRESS) on Reducing Frailty Risk in Community-Dwelling Older People

This pilot study aimed to examine the feasibility and effectiveness of a 6-months multi-component exercise program combined with twice daily consumption of either rice (RicePro) or whey-based (WheyPro) protein supplements (2 × 20 g of protein) on gait speed, grip strength and physical performance in community-dwelling pre-frail and frail older adults. Secondary outcomes included: frailty score, muscle mass, quality of life, nutritional intake, cognitive performance, depression and physical activity levels. A total of 70 participants (mean age 73.34 ± 6.85 years) were randomly allocated to either RicePro (n = 36) or WheyPro (n = 34). No adverse events were reported in regards to the exercise, however, several gastrointestinal symptoms were noted with the whey protein causing two-fold more symptoms compared to the rice protein. No differences were found between the groups (p > 0.05), except the total consumed energy (kJ) (p = 0.014) and fat (g) (p = 0.012) which was significantly lower in WheyPro. The results indicate that the quality of protein may not be as important as long as a sufficient amount is consumed.

Protein supplementation increases adaptations to endurance training: A systematic review and meta-analysis

BACKGROUND

Trials that assessed the impact of protein supplementation on endurance training adaptations have reported conflicting findings.

OBJECTIVE

To determine the impact of protein supplementation during chronic endurance training on aerobic capacity, body composition and exercise performance in healthy and clinical populations.

DESIGN

A systematic database search was conducted for randomised controlled trials addressing the effects of protein supplementation during endurance training on aerobic capacity, body composition and exercise performance in PubMed, Embase, Web of Science, and CINAHL. Meta-analyses were performed to outline the overall effects of protein supplementation with all studies containing endurance training components. The effects of endurance training and add-on effects of protein supplementation were evaluated by the meta-analyses with endurance training-focused studies.

RESULTS

Nineteen studies and 1162 participants contributed to the analyses. Compared with the control group, the protein supplementation group demonstrated greater improvements in aerobic capacity measured by mixed peak oxygen uptake (V̇O_2peak) and peak workload power (W_peak) (standardised mean difference [SMD] = 0.36, 95% confidence interval [CI]: 0.05 to 0.67), and V̇O_2peak (mean difference [MD] = 0.89 mL‧kg^-1‧min^-1, 95% CI: 0.07 to 1.70); had a greater lean mass gain (MD = 0.32 kg, 95% CI: 0.07 to 0.58); and had a greater improvement in time trial performance (MD = -29.1s, 95% CI:-55.3 to -3.0). Secondary analyses showed that, in addition to the substantial improvement in V̇O_2peak (MD = 3.67 mL‧kg^-1‧min^-1, 95% CI: 2.32 to 5.03) attributed to endurance training, protein supplementation provided an additional 26.4% gain in V̇O_2peak (MD = 0.97 mL‧kg^-1‧min^-1, 95% CI: -0.03 to 1.97).

CONCLUSION

Protein supplementation further increased aerobic capacity, stimulated lean mass gain, and improved time trial performance during chronic endurance training in healthy and clinical populations. PROSPERO REGISTRATION NUMBER: (CRD42020155239).

Nutritional Intervention to Prevent the Functional Decline in Community-Dwelling Older Adults: A Systematic Review

Aging is a global public health concern. From the age of 50, muscle mass, muscle strength and physical performance tend to decline. Sarcopenia and frailty are frequent in community-dwelling older adults and are associated with negative outcomes such as physical disability and mortality. Therefore, the identification of therapeutic strategies to prevent and fight sarcopenia and frailty is of great interest. This systematic review aims to summarize the impact of nutritional interventions alone or combined with other treatment(s) in older community-dwelling adults on (1) the three indicators of sarcopenia, i.e., muscle mass, muscle strength and physical performance; and (2) the hospitalization and readmission rates. The literature search was performed on Medline and included studies published between January 2010 and June 2020. We included randomized controlled trials of nutritional intervention alone or combined with other treatment(s) in community-living subjects aged 65 or older. In total, 28 articles were retained in the final analysis. This systematic review highlights the importance of a multimodal approach, including at least a combined nutritional and exercise intervention, to improve muscle mass, muscle strength and physical performance, in community-dwelling older adults but especially in frail and sarcopenic subjects. Regarding hospitalization and readmission rate, data were limited and inconclusive. Future studies should continue to investigate the effects of such interventions in this population.

A Call to Action: Now Is the Time to Screen Elderly and Treat Osteosarcopenia, a Position Paper of the Italian College of Academic Nutritionists MED/49 (ICAN-49)

Aging is a risk factor for the development of multiple chronic diseases, including cardiovascular disease, cancer and dementia. Life expectancy has increased in certain countries but this phenomenon is associated with a reduction of years of healthy life. Aging is associated with a number of physical and functional changes, especially sarcopenia. Sarcopenia is a clinical condition associated with a decrease in skeletal muscle and muscle strength, however, sarcopenia is a reversible condition. On the basis of the current scientific literature, sarcopenia could more appropriately capture an individual's vulnerability to negative health-related outcomes since it represents an early form of the chronic diseases. Recognition of this clinical condition can improve the management of older individuals in many different clinical settings. Despite the limitations of the indirect methods used to study body composition, the Italian College of the Academic Nutritionists ME/49 recommends that health authorities and health professionals around the world should make a greater effort to diagnose sarcopenia earlier and to manage it more effectively. In line with the development of cancer screening, the use of two diagnostic tools for sarcopenia (BIA and DXA) should be implemented.

Approaches to Assessment of Muscle Mass and Myosteatosis on Computed Tomography: A Systematic Review

BACKGROUND/OBJECTIVE

There is increasing use of computed tomography (CT) in sarcopenia research using a wide variety of techniques. We performed a systematic review of the CT literature to identify the differences between approaches used.

METHODS

A comprehensive search of PubMed from 1983 to 2017 was performed to identify studies that used CT muscle measurements to assess muscle mass and myosteatosis. The CT protocols were evaluated based on anatomic landmark(s), thresholding, muscle(s) segmented, key measurement (ie, muscle attenuation, cross-sectional area, volume), derived variables, and analysis software. From the described search, 657 articles were identified and 388 studies met inclusion criteria for this systematic review.

RESULTS

Muscle mass was more commonly assessed than myosteatosis (330 vs. 125). The most commonly assessed muscle or muscle groups were total abdominal wall musculature (142/330 and 49/125 for muscle mass and myosteatosis, respectively) and total thigh musculature (90/330 and 48/125). The most commonly used landmark in the abdomen was the L3 vertebra (123/142 and 45/49 for muscle mass and myosteatosis, respectively). Skeletal muscle index and intermuscular adipose tissue were the most commonly used measures of abdominal wall muscle mass (114/142) and myosteatosis (27/49), respectively. Cut points varied across studies. A significant majority of studies failed to report important CT technical parameters, such as use of intravenous contrast and slice thickness (94% and 63%, respectively).

CONCLUSIONS

There is considerable variation in the CT approaches used for the assessment of muscle mass and myosteatosis. There is a need to develop consensus for CT-based evaluation of sarcopenia and myosteatosis.

Whey for Sarcopenia; Can Whey Peptides, Hydrolysates or Proteins Play a Beneficial Role?

As the human body ages, skeletal muscle loses its mass and strength. It is estimated that in 10% of individuals over the age of 60, this muscle frailty has progressed to sarcopenia. Biomarkers of sarcopenia include increases in inflammatory markers and oxidative stress markers and decreases in muscle anabolic markers. Whey is a high-quality, easily digested dairy protein which is widely used in the sports industry. This review explores the evidence that whey protein, hydrolysates or peptides may have beneficial effects on sarcopenic biomarkers in myoblast cell lines, in aged rodents and in human dietary intervention trials with the older consumer. A daily dietary supplementation of 35 g of whey is likely to improve sarcopenic biomarkers in frail or sarcopenia individuals. Whey supplementation, consumed by an older, healthy adult certainly improves muscle mTOR signaling, but exercise appears to have the greatest benefit to older muscle. In vitro cellular assays are central for bioactive and bioavailable peptide identification and to determine their mechanism of action on ageing muscle.

Whey protein ingestion in elderly diet and the association with physical, performance and clinical outcomes

Nutrition is critical to the health of the elderly, since most of them have a deficiency in key nutrient. The use of whey protein may be a food strategy to increase protein intake. The objective of this work was to evaluate the ingestion of whey protein for the elderly and the association with physical performance and clinical outcomes. A systematic review was conducted in order to find papers that shed some light in the correlation between whey protein and the elderly.

INCLUSION CRITERIA

population: elderly; intervention: use of whey protein when compared to control group; outcome: related to health, nutrition, or quality of life.

DATABASE

PubMed, with papers published in the last 5 years.

SEARCH STRATEGY

(elder OR senior OR elderly OR aging OR aged OR old OR older) AND (whey OR "whey protein"). 35 papers were selected of which 22 had a physical performance outcome and 13 had clinical outcomes. Studies indicate that whey protein supplements promote protein synthesis in the elderly, improving muscle performance and aerobic capacity, protecting against sarcopenia and reducing the risk for falls. In the papers studied, the age group considered to be elderly was ≥65 years in 27 papers and ≥60 years in the other 8 papers. Whey protein also appears to contribute to improved health, recovery from disease, prevention of cardiovascular and metabolic risks, and hepatic steatosis complications. Data suggest that whey protein supplements may be promising for the health improvement of the elderly.

Effect of increased serum 25(OH)D and calcium on structure and function of post-menopausal women: a pilot study

The purpose was to determine if increasing serum 25(OH)D and calcium in postmenopausal women increased skeletal muscle size, strength, balance, and functional task performance while decreasing muscle fatigue. PCSA of the vastus lateralis increased and ascent of stairs time decreased after 6 months of increased serum 25(OH)D.

PURPOSE

The Institute of Medicine recommends ≥ 20 ng/ml of serum 25-hydroxyvitamin D [25(OH)D] for bone and overall health. Serum 25(OH)D levels have been associated with physical performance, postural sway, and falls. The purpose of this study was to determine if increasing postmenopausal women's serum 25(OH)D levels from 20-30 ng/ml to 40-50 ng/ml improved skeletal muscle size, strength, balance, and functional performance while decreasing skeletal muscle fatigue.

METHODS

Twenty-six post-menopausal women (60-85 years old) with baseline serum 25(OH)D levels between 20 and 30 ng/ml were recruited. Oral over-the-counter (OTC) vitamin D3 and calcium citrate were prescribed to increase subjects' serum 25(OH)D to levels between 40 and 50 ng/ml, serum calcium levels above 9.2 mg/dl, and PTH levels below 60 pg/ml, which were confirmed at 6 and 12 weeks. Outcome measures assessed at baseline and 6 months included muscle physiological cross-sectional area (PCSA), muscle strength, postural balance, time to perform functional tasks, and muscle fatigue. Repeated measures comparisons between baseline and follow-up were performed.

RESULTS

Nineteen subjects completed the study. One individual could not afford the time commitment for the repeated measures. Three individuals did not take their vitamin D as recommended. Two subjects were lost to follow-up (lack of interest), and one did not achieve targeted serum 25(OH)D. Vastus lateralis PCSA increased (p = 0.007) and ascent of stair time decreased (p = 0.042) after 6 months of increasing serum 25(OH)D levels from 20-30 ng/ml to 40-50 ng/ml. Isometric strength was unchanged. Anterior-posterior center of pressure (COP) excursion and COP path length decreased (p < 0.1) albeit non-significantly, suggesting balance may improve from increased serum 25(OH)D and calcium citrate levels.

CONCLUSIONS

Several measures of muscle structure and function were sensitive to elevated serum 25(OH)D and calcium levels indicating that further investigation of this phenomenon in post-menopausal women is warranted.

Lifestyle Interventions with a Focus on Nutritional Strategies to Increase Cardiorespiratory Fitness in Chronic Obstructive Pulmonary Disease, Heart Failure, Obesity, Sarcopenia, and Frailty

Cardiorespiratory fitness (CRF) is an independent predictor for all-cause and disease-specific morbidity and mortality. CRF is a modifiable risk factor, and exercise training and increased physical activity, as well as targeted medical therapies, can improve CRF. Although nutrition is a modifiable risk factor for chronic noncommunicable diseases, little is known about the effect of dietary patterns and specific nutrients on modifying CRF. This review focuses specifically on trials that implemented dietary supplementation, modified dietary pattern, or enacted caloric restriction, with and without exercise training interventions, and subsequently measured the effect on peak oxygen consumption (VO₂) or surrogate measures of CRF and functional capacity. Populations selected for this review are those recognized to have a reduced CRF, such as chronic obstructive pulmonary disease, heart failure, obesity, sarcopenia, and frailty. We then summarize the state of existing knowledge and explore future directions of study in disease states recently recognized to have an abnormal CRF.

Is There Enough Evidence for Osteosarcopenic Obesity as a Distinct Entity? A Critical Literature Review

The co-existence of impaired bone health (osteopenia/osteoporosis), reduced muscle mass and strength (sarcopenia), and increased adiposity (obesity) in middle-aged and older people has been identified in recent studies, leading to a proposal for the existence of "osteosarcopenic obesity" as a distinct entity. Evidence for the pathophysiological overlap of these conditions is mounting, although a causal relationship is yet to be established. Each component condition occurs frequently with increasing age, and with shared risk factors in many instances, thus, an overlap of these three conditions is not surprising. However, whether the concurrent existence of sarcopenia, osteoporosis and obesity leads to an increased risk of adverse musculoskeletal outcomes and mortality above and beyond the risks associated with the sum of the component parts remains to be proven and is a question of research interest. In this article, we review evidence for the existence of osteosarcopenic obesity including the current operational definition of osteosarcopenic obesity, prevalence, pathophysiology, outcomes and exploratory approaches to the management of components. We conclude that, there is insufficient evidence to support a discrete clinical entity of osteosarcopenic obesity at this time. To expand knowledge and understanding in this area, there is a need for consensus on a definition of osteosarcopenic obesity which will allow for identification, further epidemiological studies and comparisons between studies. Additionally, studies should assess whether the clinical outcomes associated with osteosarcopenic obesity are worse than the mere addition of those linked with its components. This will help to determine whether defining a person as having this triad will eventually result in a more effective treatment than addressing each of the three conditions separately.

The Role of Muscle Mass Gain Following Protein Supplementation Plus Exercise Therapy in Older Adults with Sarcopenia and Frailty Risks: A Systematic Review and Meta-Regression Analysis of Randomized Trials

Aging and frailty are associated with a high risk of lean mass (LM) loss, which leads to physical disability and can be effectively alleviated by protein supplementation (PS) and muscle strengthening exercise (MSE). In this study, the associations between LM gain and PS + MSE efficacy (measured using physical outcomes) in elderly patients with a high risk of sarcopenia or frailty were identified. A comprehensive search of online databases was performed to identify randomized controlled trials (RCTs) reporting the efficacy of PS + MSE in elderly patients with sarcopenia or frailty. The included RCTs were analyzed using meta-analysis and risk of bias assessment. We finally included 19 RCTs in this meta-analysis with a median (range/total) Physiotherapy Evidence Database score of 7/10 (5-9/10). The PS + MSE group exhibited significant improvements in the whole-body LM (standard mean difference (SMD) = 0.66; p < 0.00001), appendicular LM (SMD = 0.35; p < 0.00001), leg strength (SMD = 0.65; p < 0.00001), and walking capability (SMD = 0.33; p = 0.0006). Meta-regression analyses showed that changes in appendicular LM were significantly associated with the effect sizes of leg strength (β = 0.08; p = 0.003) and walking capability (β = 0.17; p = 0.04), respectively. Our findings suggest that LM gain after PS + MSE significantly contributes to the efficacy of the intervention in terms of muscle strength and physical mobility in elderly patients with a high risk of sarcopenia or frailty.

Clinical Value of Muscle Mass Assessment in Clinical Conditions Associated with Malnutrition

Malnutrition results from a reduction of food intake or an alteration of nutrient assimilation and leads to decreased lean mass. Strong evidence shows that malnutrition associated with loss of muscle mass negatively impacts clinical outcomes. The preservation or improvement of muscle mass represents a challenge. This review aims to (1) describe current methods to assess muscle mass in clinical practice, (2) describe the associations between muscle mass and clinical outcomes, and (3) describe the impact of interventions aiming at increasing muscle mass on clinical outcomes. It highlights the importance of assessing muscle mass as part of the screening and the follow-up of malnutrition in clinical practice.

Frailty and Rejuvenation with Stem Cells: Therapeutic Opportunities and Clinical Challenges

Frailty, one appealing target for improving successful aging of the elderly population, is a common clinical syndrome based on the accumulation of multisystemic function declines and the increase in susceptibility to stressors during biological aging. The age-dependent senescence, the frailty-related stem cell depletion, chronic inflammation, imbalance of immune homeostasis, and the reduction of multipotent stem cells collectively suggest the rational hypothesis that it is possible to (partially) cure frailty with stem cells. This systematic review has included all of the human trials of stem cell therapy for frailty from the main electronic databases and printed materials and screened the closely related reviews themed on the mechanisms of aging, frailty, and stem cells, to provide more insights in stem cell strategies for frailty, one promising method to recover health from a frail status. To date, a total of four trials about this subject have been registered on clinicaltrials.gov. The use of mesenchymal stem cells (MSCs), doses of 100 million cells, single peripheral intravenous infusion, follow-up periods of 6–12 months, and a focus primarily on safety and secondarily on efficacy are common characteristics of these studies. We conclude that intravenous infusion of allogenic MSCs is safe, well tolerated, and preliminarily effective clinically. More preclinical experiments and clinical trials are warranted to precisely elucidate the mechanism, safety, and efficacy of frailty stem cell therapy.

New insights into the anorexia of ageing: from prevention to treatment

PURPOSE OF REVIEW

Undernutrition in older adults is associated with frailty, functional decline, and mortality. The 'anorexia of ageing' is the age-related appetite and weight loss underpinning such undernutrition. This review examines the latest evidence for its prevention and treatment.

RECENT FINDINGS

Existing nutritional therapies for the anorexia of ageing include supporting nutritional intake with fortified food or supplements, including protein, omega-3 fatty acids, multivitamins, and vitamin D. The Mediterranean diet provides high fat intake and nutrient density in a moderate volume of colourful and flavoursome food and is strengthening in evidence for healthy ageing. Studies of the gut microbiome, which potentially regulates normal appetite by acting on the brain-gut communication axis, are pertinent. Utilisation of the genetic profile of individuals to determine nutritional needs is an exciting advancement of the past decade and may become common practice.

SUMMARY

Prevention or early treatment of the anorexia of ageing in older adults is critical. Latest evidence suggests that once significant weight loss has occurred, aggressive nutritional support may not result in improved outcomes.

Effect of exercise and nutritional supplementation on health-related quality of life and mood in older adults: the VIVE2 randomized controlled trial

Background

Health-related quality of life (HRQoL) and absence of depressive symptoms are of great importance for older people, which may be achieved through lifestyle interventions, e.g., exercise and nutrition interventions. The aim of this investigation was to analyze the effects of a physical activity program in combination with protein supplementation on HRQoL and depressive symptoms in community-dwelling, mobility-limited older adults.

Methods

In the Vitality, Independence, and Vigor 2 Study (VIVE2), community-dwelling men and women with an average age of 77.5 ± 5.4 years, some mobility limitations and low serum vitamin D levels (25(OH)Vit D 22.5–60 nmol/l) from two study sites (Stockholm, Sweden and Boston, USA) were randomized to receive a nutritional supplement or a placebo for 6 months. All took part in a physical activity program 2–3 times/ week. The primary outcome examined in VIVE2 was 400 M walk capacity. HRQoL was measured using the Medical Outcomes Study 36-item Short Form Health Survey (SF36), consisting of the Physical Component Summary (PCS) and Mental Component Summary (MCS), and depressive symptoms were measured using The Centre for Epidemiologic Studies Depression Scale (CES-D). In the sensitivity analyses, the sample was divided into sub-groups based on body measures and function (body mass index (BMI), appendicular lean mass index (ALMI), handgrip strength and gait speed).

Results

For the whole sample, there was a significant improvement in both MCS, mean (95% CI) 2.68 (0.5, 4.9) (p 0.02), and CES-D -2.7 (− 4.5, − 0.9) (p 0.003) during the intervention, but no difference was detected between those who received the nutritional supplement and those who received the placebo. The results revealed no significant change in PCS or variation in effects across the sub-categories.

Conclusions

This study demonstrates that a six-month intervention using a physical activity program had positive effects on mental status. No additional effects from nutritional supplementation were detected.

Trial registration

Registered at ClinicalTrials.gov, March 2 2012, NCT01542892.

The impact of exercise and vitamin D supplementation on physical function in community-dwelling elderly individuals: A randomized trial

BACKGROUND

We investigated the impact of exercise and vitamin D supplementation on physical function and locomotor dysfunction in community-dwelling elderly individuals.

METHODS

In total, 148 community-dwelling elderly individuals (aged ≥60 years) who were not taking osteoporosis medications participated in a 24-week intervention. The participants were randomly divided into an exercise group, vitamin D group, and exercise and vitamin D group. The participants and outcome-assessing staff were not blinded to group assignment. Exercise comprised three daily sets each of single-leg standing (1 min/leg/set) and squatting (5-6 repetitions/set); vitamin D supplementation was 1000 IU/day. Participants were contacted every 2 weeks to check on their condition and encourage continued participation. The primary outcome was lower limb muscle strength and mass; secondary outcomes were several physical function measurements, serum 25-hydroxyvitamin D levels, and results of a self-assessment questionnaire completed pre- and post-intervention.

RESULTS

We analyzed data from 45, 42, and 43 participants in the exercise, vitamin D, and exercise and vitamin D groups, respectively, who completed the intervention. Locomotive syndrome, which involves reduced mobility due to locomotive organ impairment, was diagnosed in 99 participants (76.2%). Many physical function measurements improved in all groups. Lower limb muscle mass increased significantly in all three groups, with no significant differences between the groups in the degree of change. The average serum 25-hydroxyvitamin D of all vitamin D-supplemented participants increased from 28.1 ng/ml to 47.3 ng/ml after vitamin D supplementation.

CONCLUSIONS

Both exercise and vitamin D supplementation independently improved physical function and increased muscle mass in community-dwelling elderly individuals. Moreover, the combination of exercise and vitamin D supplementation might further enhance these positive effects.

CLINICAL TRIAL REGISTRY

UMIN Clinical Trial, UMIN000028229.

Nutritional Supplementation With Physical Activity Improves Muscle Composition in Mobility-Limited Older Adults, The VIVE2 Study: A Randomized, Double-Blind, Placebo-Controlled Trial

Background

Nutritional supplementation and physical activity have been shown to positively influence muscle mass and strength in older adults. The efficacy of long-term nutritional supplementation in combination with physical activity in older adults remains unclear.

Methods

Mobility-limited (short physical performance battery [SPPB] ≤9) and vitamin D insufficient (serum 25(OH) D 9-24 ng/mL) older adults were recruited for this study. All subjects participated in a physical activity program. Subjects were randomized to consume a daily nutritional supplement (150 kcal, 20 g whey protein, 800 IU vitamin D, 119 mL beverage) or placebo (30 kcal, nonnutritive, 119 mL). In a prespecified secondary analysis, we examined total-body composition (dual energy X-ray absorptiometry), thigh composition (computed tomography), and muscle strength, power, and quality before and after the 6-month intervention.

Results

One hundred and forty-nine subjects were randomized into the study [mean (standard deviation, SD) age 78.5 (5.4) years; 46.3% female; mean (SD) short physical performance battery 7.9 (1.2); mean (SD) vitamin D 18.7 (6.4) ng/mL]. After the intervention period both groups demonstrated improvements in muscle strength, body composition, and thigh composition. Nutritional supplementation lead to further losses of intermuscular fat (p = .049) and increased normal muscle density (p = .018).

Conclusions

Six months of physical activity resulted in improvements in body composition, subcutaneous fat, intermuscular fat, and strength measures. The addition of nutritional supplementation resulted in further declines in intermuscular fat and improved muscle density compared to placebo. These results suggest nutritional supplementation provides additional benefits to mobility-limited older adults undergoing exercise training. ClinicalTrials.gov Identifier: NCT01542892.