The effect of a combined lifestyle intervention with and without protein drink on inflammation in older adults with obesity and type 2 diabetes

BACKGROUND

Chronic low-grade inflammatory profile (CLIP) is one of the pathways involved in type 2 diabetes (T2D). Currently, there is limited evidence for ameliorating effects of combined lifestyle interventions on CLIP in type 2 diabetes. We investigated whether a 13-week combined lifestyle intervention, using hypocaloric diet and resistance exercise plus high-intensity interval training with or without consumption of a protein drink, affected CLIP in older adults with T2D.

METHODS

In this post-hoc analysis of the PROBE study 114 adults (≥55 years) with obesity and type 2 (pre-)diabetes had measurements of C-reactive protein (CRP), pro-inflammatory cytokines interleukin (IL)-6, tumor-necrosis-factor (TNF)-α, and monocyte chemoattractant protein (MCP)-1, anti-inflammatory cytokines IL-10, IL-1 receptor antagonist (RA), and soluble tumor-necrosis-factor receptor (sTNFR)1, adipokines leptin and adiponectin, and glycation biomarkers carboxymethyl-lysine (CML) and soluble receptor for advanced glycation end products (sRAGE) from fasting blood samples. A linear mixed model was used to evaluate change in inflammatory biomarkers after lifestyle intervention and effect of the protein drink. Linear regression analysis was performed with parameters of body composition (by dual-energy X-ray absorptiometry) and parameters of insulin resistance (by oral glucose tolerance test).

RESULTS

There were no significant differences in CLIP responses between the protein and the control groups. For all participants combined, IL-1RA, leptin and adiponectin decreased after 13 weeks (p = 0.002, p < 0.001 and p < 0.001), while ratios TNF-α/IL-10 and TNF-α/IL-1RA increased (p = 0.003 and p = 0.035). CRP increased by 12 % in participants with low to average CLIP (pre 1.91 ± 0.39 mg/L, post 2.13 ± 1.16 mg/L, p = 0.006) and decreased by 36 % in those with high CLIP (pre 5.14 mg/L ± 1.20, post 3.30 ± 2.29 mg/L, p < 0.001). Change in leptin and IL-1RA was positively associated with change in fat mass (β = 0.133, p < 0.001; β = 0.017, p < 0.001) and insulin resistance (β = 0.095, p = 0.024; β = 0.020, p = 0.001). Change in lean mass was not associated with any of the biomarkers.

CONCLUSION

13 weeks of combined lifestyle intervention, either with or without protein drink, reduced circulating adipokines and anti-inflammatory cytokine IL-1RA, and increased inflammatory ratios TNF-α/IL-10 and TNF-α/IL-1RA in older adults with obesity and T2D. Effect on CLIP was inversely related to baseline inflammatory status.

The Impact of Combined Nutrition and Exercise Interventions in Patients with Chronic Kidney Disease

Combined nutrition and exercise interventions potentially improve protein-energy wasting/malnutrition-related outcomes in patients with chronic kidney disease (CKD). The aim was to systematically review the effect of combined interventions on nutritional status, muscle strength, physical performance and QoL. MEDLINE, Cochrane, Embase, Web of Science and Google Scholar were searched for studies up to the date of July 2023. Methodological quality was appraised with the Cochrane risk-of-bias tool. Ten randomized controlled trials (nine publications) were included (334 patients). No differences were observed in body mass index, lean body mass or leg strength. An improvement was found in the six-minute walk test (6-MWT) (n = 3, MD 27.2, 95%CI [7 to 48], p = 0.008), but not in the timed up-and-go test. No effect was found on QoL. A positive impact on 6-MWT was observed, but no improvements were detected in nutritional status, muscle strength or QoL. Concerns about reliability and generalizability arise due to limited statistical power and study heterogeneity of the studies included.

Malnutrition Screening Tools Are Not Sensitive Enough to Identify Older Hospital Patients with Malnutrition

This study evaluates the concurrent validity of five malnutrition screening tools to identify older hospitalized patients against the Global Leadership Initiative on Malnutrition (GLIM) diagnostic criteria as limited evidence is available. The screening tools Short Nutritional Assessment Questionnaire (SNAQ), Malnutrition Universal Screening Tool (MUST), Malnutrition Screening Tool (MST), Mini Nutritional Assessment-Short Form (MNA-SF), and the Patient-Generated Subjective Global Assessment-Short Form (PG-SGA-SF) with cut-offs for both malnutrition (conservative) and moderate malnutrition or risk of malnutrition (liberal) were used. The concurrent validity was determined by the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and the level of agreement by Cohen's kappa. In total, 356 patients were included in the analyses (median age 70 y (IQR 63-77); 54% male). The prevalence of malnutrition according to the GLIM criteria without prior screening was 42%. The conservative cut-offs showed a low-to-moderate sensitivity (32-68%) and moderate-to-high specificity (61-98%). The PPV and NPV ranged from 59 to 94% and 67-86%, respectively. The Cohen's kappa showed poor agreement (k = 0.21-0.59). The liberal cut-offs displayed a moderate-to-high sensitivity (66-89%) and a low-to-high specificity (46-95%). The agreement was fair to good (k = 0.33-0.75). The currently used screening tools vary in their capacity to identify hospitalized older patients with malnutrition. The screening process in the GLIM framework requires further consideration.

Minerals and Sarcopenia in Older Adults: An Updated Systematic Review

OBJECTIVE

This systematic review aims to reevaluate the role of minerals on muscle mass, muscle strength, physical performance, and the prevalence of sarcopenia in community-dwelling and institutionalized older adults.

DESIGN

Systematic review.

SETTING AND PARTICIPANTS

In March 2022, a systematic search was performed in PubMed, Scopus, and Web of Sciences using predefined search terms. Original studies on dietary mineral intake or mineral serum blood concentrations on muscle mass, muscle strength, and physical performance or the prevalence of sarcopenia in older adults (average age ≥65 years) were included.

METHODS

Eligibility screening and data extraction was performed by 2 independent reviewers. Quality assessment was performed with the Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for Quantitative Studies. Risk of bias was evaluated using the Risk Of Bias In Non-randomized Studies-of Exposure (ROBINS-E) tool.

RESULTS

From the 15,622 identified articles, a total of 45 studies were included in the review, mainly being cross-sectional and observational studies. Moderate quality of evidence showed that selenium (n = 8) and magnesium (n = 7) were significantly associated with muscle mass, strength, and physical performance as well as the prevalence of sarcopenia. For calcium and zinc, no association could be found. For potassium, iron, sodium, and phosphorus, the association with sarcopenic outcomes remains unclear as not enough studies could be included or were nonconclusive (low quality of evidence).

CONCLUSIONS AND IMPLICATIONS

This systematic review shows a potential role for selenium and magnesium on the prevention and treatment of sarcopenia in older adults. More randomized controlled trials are warranted to determine the impact of minerals on sarcopenia in older adults.

Effects of Nutritional Interventions in Older Adults with Malnutrition or at Risk of Malnutrition on Muscle Strength and Mortality: Results of Pooled Analyses of Individual Participant Data from Nine RCTs

Nutritional intervention studies in older adults with malnutrition aim to improve nutritional status. Although these studies show a significant gain in body weight, there is inconsistent evidence of clinical effectiveness on muscle strength and mortality. This study aimed to examine the effects of nutritional interventions on muscle strength and risk of mortality in older adults (malnourished or at risk) and explore whether these effects are influenced by participant characteristics. Individual participant data were used from nine RCTs (community setting, hospital and long-term care; duration 12-24 weeks and included oral nutritional supplements, dietary counseling, or both). Handgrip strength (HGS) was measured in seven RCTs and six RCTs obtained mortality data. A ≥3 kg increase in HGS was considered clinically relevant. Logistic generalized estimating equations analyses (GEE) were used to test intervention effectiveness. GEE showed no overall treatment effect (OR 1.11, 95% CI 0.78-1.59) on HGS. A greater, but not statistically significant, effect on HGS was observed for older (>80 years) versus younger participants. No significant treatment effect was observed for mortality (OR 0.78, 95% CI 0.42-1.46). The treatment effect on mortality was greater but remained non-significant for women and those with higher baseline energy or protein intake. In conclusion, no effects of nutritional interventions were observed on HGS and mortality in older adults (malnourished or at risk). While the treatment effect was modified by some baseline participant characteristics, the treatment also lacked an effect in most subgroups.

Additional effects of exercise to hypocaloric diet on body weight, body composition, glycaemic control, and cardio-respiratory fitness in adults with overweight or obesity and type 2 diabetes: a systematic review and meta-analysis

AIMS

This systematic review and meta-analysis evaluates the additional effect of exercise to hypocaloric diet on body weight, body composition, glycaemic control, and cardio-respiratory fitness in adults with overweight or obesity and type 2 diabetes.

METHODS

Embase, Medline, Web of Science, and Cochrane Central databases were evaluated, and 11 studies were included. Random-effects meta-analysis was performed on body weight and measures of body composition and glycaemic control, to compare the effect of hypocaloric diet plus exercise with hypocaloric diet alone.

RESULTS

Exercise interventions consisted of walking or jogging, cycle ergometer training, football training, or resistance training, and duration varied from 2 to 52 weeks. Body weight and measures of body composition and glycaemic control decreased during both the combined intervention and hypocaloric diet alone. Mean difference in change of body weight (-0.77 kg [95%-CI: -2.03; 0.50]), BMI (-0.34 kg/m² [95%-CI -0.73; 0.05]), waist circumference (-1.42 cm [95%-CI: -3.84; 1.00]), fat-free mass (-0.18 kg [95%-CI -0.52; 0.17]), fat mass (-1.61 kg [95%-CI -4.42; 1.19]), fasting glucose (+0.14 mmol/l [95%-CI -0.02; 0.30]), HbA_1c (-1 mmol/mol [95%-CI -0.2; 0.1], -0.1 % [95%-CI -0.2; 0.1]), and HOMA-IR (+0.01 [95%-CI: -0.40; 0.42]) was not statistically different between the combined intervention and hypocaloric diet alone. Two studies reported VO_2max and showed significant increases upon addition of exercise to hypocaloric diet.

CONCLUSIONS

Based on limited data, we did not find additional effects of exercise to hypocaloric diet in adults with overweight or obesity and type 2 diabetes on body weight, body composition, or glycaemic control, while cardio-respiratory fitness improved.

Interprofessional Treatment of Malnutrition and Sarcopenia by Dietitians and Physiotherapists: Exploring Attitudes, Interprofessional Identity, Facilitators, Barriers, and Occurrence

Purpose

Malnutrition and sarcopenia require dietetic and physiotherapy interventions. In this study, we aimed to compare interprofessional identity of dietitians and physiotherapists, as well as attitudes towards, facilitators and barriers for, and occurrence of interprofessional treatment of malnutrition and sarcopenia by both professions.

Methods

A cross-sectional online survey was distributed from December 4, 2021 until January 31, 2022 through an international online network platform for professionals (LinkedIn). Practitioners working as dietitian or physiotherapist in a healthcare setting were eligible for participation. Outcome measures concerned perceptions regarding shared problem domains, interprofessional treatment, attitudes towards interprofessional treatment, interprofessional identity, facilitators, and barriers. A Chi²-test, Mann–Whitney U-test, and Spearman’s Rho correlation were calculated.

Results

Data from 53 physiotherapists and 48 dietitians were included. Malnutrition is considered a shared problem domain by both professions (U = 1248.000; p = 0.858). While sarcopenia is treated by both professions (U = 1260.000; p = 0.927), physiotherapists consider sarcopenia more often a shared problem domain compared to dietitians (U = 1003.000; p = 0.044). Attitudes towards interprofessional treatment were mostly positive (73%, n = 35 and 87%, n = 46 respectively). Interprofessional identity of dietitians was lower compared to physiotherapists (median = 4.0 versus median = 4.3 respectively; U = 875.000, p = 0.007). This was explained by lower interprofessional belonging (median = 4.0 versus median = 4.8 respectively; U = 771.000, p < 0.001) and lower interprofessional commitment (median = 4.0 versus median = 4.3 respectively; U = 942.500, p = 0.023). Interprofessional identity was correlated with efficient means of communication (r = 0.30, p = 0.003) and bureaucracy (r = −0.21, p = 0.034). Other barriers reported included available time, financial compensation, interprofessional knowledge, and obtaining extra care. Most reported facilitators concerned role clarity, clarity of expertise, and willingness of others to collaborate.

Conclusion

Dietitians and physiotherapists have different interprofessional identities, but both are advocates of interprofessional treatment. Both professions mostly treat malnutrition and sarcopenia individually and have different perceptions regarding sarcopenia as shared problem domain. Facilitators were mainly related to clarity and commitment while barriers were mainly related to resources.

Bio-Electrical Impedance Analysis: A Valid Assessment Tool for Diagnosis of Low Appendicular Lean Mass in Older Adults?

Background

The diagnosis of sarcopenia is essential for early treatment of sarcopenia in older adults, for which assessment of appendicular lean mass (ALM) is needed. Multi-frequency bio-electrical impedance analysis (MF-BIA) may be a valid assessment tool to assess ALM in older adults, but the evidences are limited. Therefore, we validated the BIA to diagnose low ALM in older adults.

Methods

ALM was assessed by a standing-posture 8 electrode MF-BIA (Tanita MC-780) in 202 community-dwelling older adults (age ≥ 55 years), and compared with dual-energy X-ray absorptiometry (DXA) (Hologic Inc., Marlborough, MA, United States; DXA). The validity for assessing the absolute values of ALM was evaluated by: (1) bias (mean difference), (2) percentage of accurate predictions (within 5% of DXA values), (3) the mean absolute error (MAE), and (4) limits of agreement (Bland–Altman analysis). The lowest quintile of ALM by DXA was used as proxy for low ALM (< 22.8 kg for men, < 16.1 kg for women). Sensitivity and specificity of diagnosing low ALM by BIA were assessed.

Results

The mean age of the subjects was 72.1 ± 6.4 years, with a BMI of 25.4 ± 3.6 kg/m², and 71% were women. BIA slightly underestimated ALM compared to DXA with a mean bias of −0.6 ± 1.2 kg. The percentage of accurate predictions was 54% with a MAE of 1.1 kg, and limits of agreement were −3.0 to + 1.8 kg. The sensitivity for ALM was 80%, indicating that 80% of subjects who were diagnosed as low ALM according to DXA were also diagnosed low ALM by BIA. The specificity was 90%, indicating that 90% of subjects who were diagnosed as normal ALM by DXA were also diagnosed as normal ALM by the BIA.

Conclusion

This comparison showed a poor validity of MF-BIA to assess the absolute values of ALM, but a reasonable sensitivity and specificity to recognize the community-dwelling older adults with the lowest muscle mass.

Sarcopenia and its relation to protein intake across older ethnic populations in the Netherlands: the HELIUS study

Objective: To examine the prevalence of sarcopenia and its association with protein intake in men and women in a multi-ethnic population.Design: We used cross-sectional data from the HELIUS (Healthy Life in an Urban Setting) study, which includes nearly 25,000 participants (aged 18-70 years) of Dutch, South-Asian Surinamese, African Surinamese, Turkish, Moroccan, and Ghanaian ethnic origin. For the current study, we included 5161 individuals aged 55 years and older. Sarcopenia was defined according to the EWGSOP2. In a subsample (N = 1371), protein intake was measured using ethnic-specific Food Frequency Questionnaires. Descriptive analyses were performed to study sarcopenia prevalence across ethnic groups in men and women, and logistic regression analyses were used to study associations between protein intake and sarcopenia.Results: Sarcopenia prevalence was found to be sex- and ethnic-specific, varying from 29.8% in Turkish to 61.3% in South-Asian Surinamese men and ranging from 2.4% in Turkish up to 30.5% in South-Asian Surinamese women. Higher protein intake was associated with a 4% lower odds of sarcopenia in the subsample (OR = 0.96, 95%-CI: 0.92-0.99) and across ethnic groups, being only significant in the South-Asian Surinamese group.Conclusion: Ethnic differences in the prevalence of sarcopenia and its association with protein intake suggest the need to target specific ethnic groups for prevention or treatment of sarcopenia.

Relative Validity and Reliability of Isometric Lower Extremity Strength Assessment in Older Adults by Using a Handheld Dynamometer

BACKGROUND

Handheld dynamometry (HHD) is a practical alternative to traditional testing of lower extremity strength. However, its reliability and validity across different populations and settings are not clear.

HYPOTHESIS

We hypothesize that HHD is a valid and reliable device to assess lower extremity strength in a population of older adults.

STUDY DESIGN

Cross-sectional/cohort.

LEVEL OF EVIDENCE

Level 3.

METHODS

This study included 258 older adults (≥65 years). Isometric knee extension and flexion force were measured by 1 examiner, using an HHD (n = 222), including 3 repetitions to calculate within-day intrarater reliability. These measurements were repeated by the examiner in a subgroup (n = 23) to analyze intrarater reliability over a test-retest period of on average 8 weeks. In addition, HHD force measures were performed by a second examiner (n = 29) to analyze interrater reliability. In another subgroup (n = 77), isometric knee extension and flexion torque were measured by 1 examiner using both the HHD and Biodex System 4 to assess relative validity.

RESULTS

HHD and Biodex measurements were highly correlated and showed excellent concurrent validity. HHD systematically overestimated torque as compared with Biodex by 8 N·m on average. Same-day intrarater intraclass correlation coefficients (ICCs) ranged from 0.97 to 0.98. Interrater reliability ICCs ranged from 0.83 to 0.95.

CONCLUSION

HHD represents a reliable and valid alternative to Biodex to rank individuals on leg strength, or to assess within-person changes in leg strength over time, because of the high validity and reliability. The HHD is less suited for absolute strength assessment because of significant systematic overestimations.

CLINICAL RELEVANCE

Clinicians are encouraged to use HHD to rank older adults on leg strength, or to assess within-person changes in leg strength over time, but not to compare readings with cut-offs or normative values.

The Relevance of Diet, Physical Activity, Exercise, and Persuasive Technology in the Prevention and Treatment of Sarcopenic Obesity in Older Adults

The aging population faces two conditions that threaten healthy aging: high fat mass (obesity) and low muscle mass and function (sarcopenia). The combination of both-referred to as sarcopenic obesity-synergistically increases the risk of adverse health outcomes. The two conditions often co-occur because they reinforce each other and share common etiologies, including poor nutrition and inactivity. All aging people are at risk of gaining weight and losing muscle mass and could benefit from improvements in physical activity, exercise and dietary intake. one specific window of opportunity is during the transient time of retirement, as older adults already need to restructure their daily activities. It is key to change lifestyle behavior in a sustainable manner, providing scientifically proven, personalized, and acceptable principles that can be integrated in daily life. Health technologies (e.g., applications) can provide promising tools to deliver personalized and appealing lifestyle interventions to a large group of people while keeping health care costs low. Several studies show that health technologies have a strong positive effect on physical activity, exercise and dietary intake. Specifically, health technology is increasingly applied to older people, although strong evidence for long term effects in changing lifestyle behavior is generally lacking. Concluding, technology could play an important role in the highly warranted prevention of sarcopenic obesity in older adults. Although health technology seems to be a promising tool to stimulate changes in physical activity, exercise and dietary intake, studies on long lasting effects and specifically targeted on older people around the time of retirement are warranted.

A higher protein intake at breakfast and lunch is associated with a higher total daily protein intake in older adults: a post-hoc cross-sectional analysis of four randomised controlled trials

BACKGROUND

A protein intake of 30-40 g per meal is suggested to maximally stimulate muscle protein synthesis in older adults and could therefore contribute to the prevention of sarcopenia. Protein intake at breakfast and lunch is often low and offers a great opportunity to improve daily protein intake. Protein, however, is known for its satiating effects. Therefore, we explored the association between the amount of protein intake at breakfast and lunch and total daily protein intake in older adults.

METHODS

Protein intake was assessed by a 3-day food record in 498 community dwelling older adults (≥55 years) participating different lifestyle interventions. Linear mixed model analysis was used to examine the association between protein intake at breakfast or lunch and total daily protein intake, adjusted for sex, age, body mass index, smoking status, study and total energy intake.

RESULTS

After adjustment for potential confounders, a 10 g higher protein intake at breakfast was associated with a 3.2 g higher total daily protein intake (P = 0.008) for males and a 4.9 g (P < 0.001) higher total daily protein intake for females. A 10 g higher protein intake at lunch was associated with a 3.7 g higher total daily protein intake (P < 0.001) for males, and a 5.8 g higher total daily protein intake (P < 0.001) for females.

CONCLUSIONS

A higher protein intake at breakfast and lunch is associated with a higher total daily protein intake in community dwelling older adults. Stimulating a higher protein intake at breakfast and lunch might represent a promising nutritional strategy to optimise the amount of protein per meal without compromising total daily protein intake.

Digitally Supported Dietary Protein Counseling Changes Dietary Protein Intake, Sources and Distribution in Community-Dwelling Older Adults

Digitally supported dietary counselling may be helpful in increasing the protein intake in combined exercise and nutritional interventions in community-dwelling older adults. To study the effect of this approach, 212 older adults (72.2 ± 6.3 years) were randomised in three groups: control, exercise, or exercise plus dietary counselling. The dietary counselling during the 6-month intervention was a blended approach of face-to-face contacts and videoconferencing, and it was discontinued for a 6-month follow-up. Dietary protein intake, sources, product groups, resulting amino acid intake, and intake per eating occasion were assessed by a 3-day dietary record. The dietary counselling group was able to increase the protein intake by 32% at 6 months, and the intake remained 16% increased at 12 months. Protein intake mainly consisted of animal protein sources: dairy products, followed by fish and meat. This resulted in significantly more intake of essential amino acids, including leucine. The protein intake was distributed evenly over the day, resulting in more meals that reached the protein and leucine targets. Digitally supported dietary counselling was effective in increasing protein intake both per meal and per day in a lifestyle intervention in community-dwelling older adults. This was predominantly achieved by consuming more animal protein sources, particularly dairy products, and especially during breakfast and lunch.

Dietary Protein Intake in Older Adults from Ethnic Minorities in the Netherlands, a Mixed Methods Approach

Optimizing protein intake is a novel strategy to prevent age associated loss of muscle mass and strength in older adults. Such a strategy is still missing for older adults from ethnic minority populations. Protein intake in these populations is expected to be different in comparison to the majority of the population due to several socio-cultural factors. Therefore, the present study examined the dietary protein intake and underlying behavioral and environmental factors affecting protein intake among older adults from ethnic minorities in the Netherlands. We analyzed frequency questionnaire (FFQ) data from the Healthy Life in an Urban Setting (HELIUS) cohort using ANCOVA to describe dietary protein intake in older adults from ethnic minorities in the Netherlands (N = 1415, aged >55 years, African Surinamese, South Asian Surinamese, Moroccan, and Turkish). Additionally, we performed focus groups among older adults from the same ethnic minority populations (N = 69) to discover behavioral and environmental factors affecting protein intake; 40-60% of the subjects did not reach minimal dietary protein recommendations needed to maintain muscle mass (1.0 g/kg bodyweight per day (BW/day)), except for Turkish men (where it was 91%). The major sources of protein originated from animal products and were ethnic specific. Participants in the focus groups showed little knowledge and awareness about protein and its role in aging. The amount of dietary protein and irregular eating patterns seemed to be the major concern in these populations. Optimizing protein intake in these groups requires a culturally sensitive approach, which accounts for specific protein product types and sociocultural factors.

Blended home-based exercise and dietary protein in community-dwelling older adults: a cluster randomized controlled trial

BACKGROUND

Effective and sustainable interventions are needed to counteract the decline in physical function and sarcopenia in the growing aging population. The aim of this study was to determine the 6 and 12 month effectiveness of blended (e-health + coaching) home-based exercise and a dietary protein intervention on physical performance in community-dwelling older adults.

METHODS

This cluster randomized controlled trial allocated 45 clusters of older adults already engaged in a weekly community-based exercise programme. The clusters were randomized to three groups with ratio of 16:15:14; (i) no intervention, control (CON); (ii) blended home-based exercise intervention (HBex); and (iii) HBex with dietary protein counselling (HBex-Pro). Both interventions used a tablet PC with app and personalized coaching and were targeting on behaviour change. The study comprised coached 6 month interventions with a 6 month follow-up. The primary outcome physical performance was assessed by modified Physical Performance Test (m-PPT). Secondary outcomes were gait speed, physical activity level (PAL), handgrip muscle strength, protein intake, skeletal muscle mass, health status, and executive functioning. Linear mixed models of repeated measured were used to assess intervention effects at 6 and 12 months.

RESULTS

The population included 245 older adults (mean age 72 ± 6.5 (SD) years), 71% female, and 54% co-morbidities observed. Dropout of the intervention was 18% at 6 months and 26% at 12 months. Participants were well functioning, based on an m-PPT score of 33.9 (2.8) out of 36. For the primary outcome m-PPT, no significant intervention effects (HBex, +0.03, P = 0.933; HBex-Pro, -0.13, P = 0.730) were found. Gait speed (+0.20 m/s, P = 0.001), PAL (+0.06, P = 0.008), muscle strength (+2.32 kg, P = 0.001), protein intake (+0.32 g/kg/day, P < 0.001), and muscle mass (+0.33 kg, P = 0.017) improved significantly in the HBex-Pro group compared with control group after 6 month intervention. The protein intake, muscle mass, and strength remained significantly improved after 12 months as compared with those of control. Health change and executive functioning improved significantly in both intervention groups after 6 months.

CONCLUSIONS

This HBex and dietary protein interventions did not change the physical performance (m-PPT) in community-dwelling older adults. Changes were observed in gait speed, PAL, muscle mass, strength, and dietary protein intake, in response to this combined intervention.

Determinants of dietary behaviour in wheelchair users with spinal cord injury or lower limb amputation: Perspectives of rehabilitation professionals and wheelchair users

Objective

This study aims to identify determinants of dietary behaviour in wheelchair users with spinal cord injury or lower limb amputation, from the perspectives of both wheelchair users and rehabilitation professionals. The findings should contribute to the field of health promotion programs for wheelchair users.

Methods

Five focus groups were held with wheelchair users (n = 25), and two with rehabilitation professionals (n = 11). A thematic approach was used for data analysis in which the determinants were categorized using an integrated International Classification of Functioning, Disability and Health and Attitude, Social influence and self-Efficacy model.

Results

Reported personal factors influencing dietary behaviour in wheelchair users were knowledge, boredom, fatigue, stage of life, habits, appetite, self-control, multiple lifestyle problems, intrinsic motivation, goal setting, monitoring, risk perception, positive experiences, suffering, action planning, health condition, function impairments, attitude and self-efficacy. Reported environmental factors influencing dietary behaviour in wheelchair users were unadjusted kitchens, monitoring difficulties, eating out, costs, unfavourable food supply, nutrition education/counselling, access to simple healthy recipes, eating together, cooking for others, and awareness and support of family and friends.

Conclusions

Important modifiable determinants of dietary behaviour in wheelchair users that might be influenced in lifestyle interventions are knowledge, fatigue, habits, self-control, intrinsic motivation, risk perception, attitude and self-efficacy. It is recommended to involve relatives, since they appear to significantly influence dietary behaviour.

Dietary Protein, Exercise, and Frailty Domains

Increasing awareness of the impact of frailty on elderly people resulted in research focusing on factors that contribute to the development and persistence of frailty including nutrition and physical activity. Most effort so far has been spent on understanding the association between protein intake and the physical domain of frailty. Far less is known for other domains of frailty: cognition, mood, social health and comorbidity. Therefore, in the present narrative review, we elaborate on the evidence currently known on the association between protein and exercise as well as the broader concept of frailty. Most, but not all, identified studies concluded that low protein intake is associated with a higher prevalence and incidence of physical frailty. Far less is known on the broader concept of frailty. The few studies that do look into this association find a clear beneficial effect of physical activity but no conclusions regarding protein intake can be made yet. Similar, for other important aspects of frailty including mood, cognition, and comorbidity, the number of studies are limited and results are inconclusive. Future studies need to focus on the relation between dietary protein and the broader concept of frailty and should also consider the protein source, amount and timing.

Decreased Appetite is Associated with Sarcopenia-Related Outcomes in Acute Hospitalized Older Adults

Decreased appetite is one of the main risk factors of malnutrition. Little is known on how appetite changes during hospitalization and after discharge and how it relates with sarcopenia-related outcomes. We analyzed data of the Hospital-ADL study, a multicenter prospective cohort study that followed 400 acutely hospitalized older adults (≥70 year). Appetite (SNAQ), handgrip strength (Jamar), muscle mass (BIA), mobility (DEMMI), and physical performance (SPPB) were assessed within 48 h of admission, at discharge, and at one and three months post-discharge. The course of decreased appetite was analysed by Generalised Estimating Equations. Linear Mixed Model was used to analyse the associations between decreased appetite and the sarcopenia-related outcomes. Decreased appetite was reported by 51% at hospital admission, 34% at discharge, 28% one month post-discharge, and 17% three months post-discharge. Overall, decreased appetite was associated with lower muscle strength (β = −1.089, p = 0.001), lower mobility skills (β = −3.893, p < 0.001), and lower physical performance (β = −0.706, p < 0.001) but not with muscle mass (β = −0.023, p = 0.920). In conclusion, decreased appetite was highly prevalent among acute hospitalized older adults and remained prevalent, although less, after discharge. Decreased appetite was significantly associated with negative sarcopenia-related outcomes, which underlines the need for assessment and monitoring of decreased appetite during and post hospitalization.

Sarcopenic obesity in the ICU

PURPOSE OF REVIEW

Sarcopenic obese in older ICU patients may have a higher risk of poor recovery during and after ICU stay, which may lead to longer hospital stay and poor quality of life. In this review, causes, consequences, and nutrition strategies to combat sarcopenic obesity in the ICU are discussed.

RECENT FINDINGS

Physical inactivity, inflammation, anabolic resistance, as well as disturbances in hormone levels are, important causes for the strongly accelerated decline in muscle mass and muscle strength in ICU patients. These causes may lead to changes in amino acid metabolism and anabolic resistance. Obese individuals show specific muscle characteristics (e.g. adipose infiltration, lower capillary density) which are associated with impaired functionality. Specific energy and protein intake recommendations are needed to attenuate sarcopenic obesity in ICU patients.

SUMMARY

Nutrient utilization in sarcopenic obese ICU patients is a complex challenge as many metabolic factors and clinical situations may impact the efficacy of nutritional interventions. Nutritional strategies should consist of high-protein and hypocaloric feeding along with nonprotein sources such as vitamin D, omega-3 fatty acids, or physical activity. There is a great need, however, for randomized controlled trials (RCTs) combining various nutritional strategies with physical activity in sarcopenic obese ICU patients.

A digitally supported home-based exercise training program and dietary protein intervention for community dwelling older adults: protocol of the cluster randomised controlled VITAMIN trial

Background

Increased physical activity and dietary protein intake are promising interventions to prevent or treat the age-related decline in physical performance in older adults. There are well-controlled exercise as well as dietary intervention studies that show beneficial effects on physical performance in older adults. In practice, however, weekly group based exercise or nutritional programs may not be as effective. To optimise these exercise programs for community dwelling older adults, a digitally supported and personalised home-based exercise training program has been designed aiming to improve physical performance in older adults. In addition, a protein intervention in combination with the training program may further improve physical performance in older adults.

Methods

The VITAMIN study will be a cluster randomised controlled trial with three parallel arms. In total, 240 community dwelling older adults (≥ 55 years) participating in weekly group exercise are randomly allocated into: 1) regular weekly exercise program (Control group, n = 80), 2) digitally supported personalised home-based exercise training program group (VITA group, n = 80) and 3) digitally supported personalised home-based exercise training program group plus dietary protein counselling (VITA-Pro group, n = 80). The VITAMIN study aims to evaluate effectiveness of the digitally supported personalised home-based exercise training program as well as the additional value of dietary protein on physical performance after 6 months. In addition, a 12 month follow-up measurement will assess the retaining effect of the interventions. Primary outcome is physical performance measured by the Modified Physical Performance Test (M-PPT) and relevant secondary and observational outcomes include habitual physical activity and dietary intake, body composition, cognitive performance, quality of life, compliance and tablet usage. Data will be analysed by Linear Mixed Models.

Discussion

To our knowledge, the VITAMIN study is the first study that investigates the impact of home-based exercise, protein intake as well as use of persuasive technology in the population of community dwelling older adults.

Trial registration

NL56094.029.16 / NTR (TC = 5888; registered 03–06-2016).

Exercise and Nutrition Strategies to Counteract Sarcopenic Obesity

As the population is aging rapidly, there is a strong increase in the number of individuals with chronic disease and physical limitations. The decrease in skeletal muscle mass and function (sarcopenia) and the increase in fat mass (obesity) are important contributors to the development of physical limitations, which aggravates the chronic diseases prognosis. The combination of the two conditions, which is referred to as sarcopenic obesity, amplifies the risk for these negative health outcomes, which demonstrates the importance of preventing or counteracting sarcopenic obesity. One of the main challenges is the preservation of the skeletal muscle mass and function, while simultaneously reducing the fat mass in this population. Exercise and nutrition are two key components in the development, as well as the prevention and treatment of sarcopenic obesity. The main aim of this narrative review is to summarize the different, both separate and combined, exercise and nutrition strategies so as to prevent and/or counteract sarcopenic obesity. This review therefore provides a current update of the various exercise and nutritional strategies to improve the contrasting body composition changes and physical functioning in sarcopenic obese individuals.

Cholecalciferol or 25-Hydroxycholecalciferol Supplementation Does Not Affect Muscle Strength and Physical Performance in Prefrail and Frail Older Adults

Background

Vitamin D supplementation is proposed as a potential treatment strategy to counteract functional decline in older adults. However, data from randomized trials are either limited or inconsistent.

Objective

This study investigated the effect of daily supplementation with 25-hydroxycholecalciferol [25(OH)D3] or cholecalciferol (vitamin D3) on muscle strength and physical performance in older adults.

Methods

This was a randomized, double-blind, placebo-controlled trial of 6 mo including 78 prefrail or frail (according to the Fried criteria), community-dwelling older adults (n = 43 men) aged ≥65 y, with a baseline 25-hydroxyvitamin D [25(OH)D] concentration between 20 and 50 nmol/L. Participants were supplemented daily with 10 µg 25(OH)D3, 20 µg vitamin D3, or a placebo capsule. Serum 25(OH)D was measured by liquid chromatography-tandem mass spectrometry. The primary outcome was maximal isometric knee-extension strength (Biodex System 4); secondary outcomes included knee-flexion and hand grip strength, Short-Physical Performance Battery score, Timed Up and Go score, postural sway, muscle mass (dual-energy X-ray absorptiometry), and muscle fiber type and size.

Results

The mean baseline serum 25(OH)D concentration was 37.7 nmol/L (95% CI: 35.4, 39.9 nmol/L). After 6 mo of supplementation, concentrations increased to 98.7 nmol/L (95% CI: 93.1, 104.4 nmol/L) in the 25(OH)D3 group and to 72.0 nmol/L (95% CI: 66.1, 77.8 nmol/L) in the vitamin D3 group, compared with 47.5 nmol/L (95% CI: 41.8, 53.3 nmol/L) in the placebo group (P-interaction < 0.01). Knee-extension strength did not significantly change in the 25(OH)D3 group (5.9 Nm; 95% CI: -6.2, 18.0 Nm), in the vitamin D3 group (5.5 Nm; 95% CI: -6.8, 17.8 Nm), or in the placebo group (1.8 Nm; 95% CI: -10.7, 14.4 Nm) (P-interaction = 0.74). Furthermore, mean changes in physical performance tests, muscle mass, and muscle fiber type and size did not differ between the groups.

Conclusion

Increasing the serum 25(OH)D concentration over a period of 6 mo did not significantly change muscle strength and physical performance in prefrail and frail older adults. This trial was registered at www.clinicaltrials.gov as NCT02349282.

Attenuated strength gains during prolonged resistance exercise training in older adults with high inflammatory status

OBJECTIVES

Chronic systemic low grade inflammation is associated with the age-related loss of muscle mass. Resistance exercise has been suggested to reduce or lower chronic systemic low grade inflammation. However, systemic chronic low-grade inflammation may adversely affect the adaptive response to exercise training. We investigated the effect of resistance exercise training on systemic chronic low-grade inflammation in older adults. In addition, we studied the association between systemic chronic low-grade inflammation and the adaptive response to exercise training.

DESIGN/SETTING/PARTICIPANTS

Frail and pre-frail older adults (61 subjects) performed 24 weeks of progressive resistance exercise training. Frailty was assessed using the Fried frailty criteria.

MEASUREMENTS

Lean body mass (DXA), strength (1RM), circulating levels of IL-1β, IL-6, IL-8 and TNF-α were measured prior to exercise training, after 12 weeks of training, and after 24 weeks of training.

RESULTS

Prolonged progressive resistance exercise training did not affect circulating levels of IL-6, IL-8 and TNF-α. However, exercise training led to a small but significant increase of 0.052 pg/mL in IL-1β. Higher circulating levels of TNF-α, IL-8 and IL-6 during the training period were negatively associated with strength gains for the leg press. A doubling of plasma TNF-α, IL-8 or IL-6 resulted in reduced strength gains for leg press with coefficients of -3.52, -3.42 and -1.54 respectively. High levels of circulating TNF-α were also associated with decreased strength gains for the leg extension (coefficient -1.50). Inflammatory cytokines did not appear to have an effect on gains in lean mass.

CONCLUSION

Our findings suggest that increased levels of plasma cytokines (TNF-α, IL-6 and IL-8) are associated with lower strength gains during resistance exercise training.

Skeletal muscle performance and ageing

The world population is ageing rapidly. As society ages, the incidence of physical limitations is dramatically increasing, which reduces the quality of life and increases healthcare expenditures. In western society, ~30% of the population over 55 years is confronted with moderate or severe physical limitations. These physical limitations increase the risk of falls, institutionalization, co-morbidity, and premature death. An important cause of physical limitations is the age-related loss of skeletal muscle mass, also referred to as sarcopenia. Emerging evidence, however, clearly shows that the decline in skeletal muscle mass is not the sole contributor to the decline in physical performance. For instance, the loss of muscle strength is also a strong contributor to reduced physical performance in the elderly. In addition, there is ample data to suggest that motor coordination, excitation-contraction coupling, skeletal integrity, and other factors related to the nervous, muscular, and skeletal systems are critically important for physical performance in the elderly. To better understand the loss of skeletal muscle performance with ageing, we aim to provide a broad overview on the underlying mechanisms associated with elderly skeletal muscle performance. We start with a system level discussion and continue with a discussion on the influence of lifestyle, biological, and psychosocial factors on elderly skeletal muscle performance. Developing a broad understanding of the many factors affecting elderly skeletal muscle performance has major implications for scientists, clinicians, and health professionals who are developing therapeutic interventions aiming to enhance muscle function and/or prevent mobility and physical limitations and, as such, support healthy ageing.

An Even Distribution of Protein Intake Daily Promotes Protein Adequacy but Does Not Influence Nutritional Status in Institutionalized Elderly

OBJECTIVE

Although it has been established that sufficient protein is required to maintain good nutritional status and support healthy aging, it is not clear if the pattern of protein consumption may also influence nutritional status, especially in institutionalized elderly who are at risk of malnutrition. Therefore, we aim to determine the association between protein intake distribution and nutritional status in institutionalized elderly people.

DESIGN

Cross-sectional study among 481 institutionalized older adults.

METHODS

Dietary data from 481 ambulant elderly people (68.8% female, mean age 87.5 ± 6.3 years) residing in 52 aged-care facilities in Victoria, Australia, were assessed over 2 days using plate waste analysis. Nutritional status was determined using the Mini-Nutritional Assessment tool and serum (n = 208) analyzed for albumin, hemoglobin, and IGF-1. Protein intake distribution was classified as: spread (even distribution across 3 meals, n = 65), pulse (most protein consumed in one meal, n = 72) or intermediate (n = 344). Regression analysis was used to investigate associations.

RESULTS

Mean protein intakes were higher in the spread (60.5 ± 2.0 g/d) than intermediate group (56.0 ± 0.8 g/d, P = .037), and tended to be higher than those in the pulse group (55.9 ± 1.9 g/d, P = .097). Residents with an even distribution of protein intake achieved a higher level of the recommended daily intake for protein (96.2 ± 30.0%) than the intermediate (86.3 ± 26.2%, P = .008) and pulse (87.4 ± 30.5%, P = .06) groups, and also achieved a greater level of their estimated energy requirements (intermediate; P = .039, pulse; P = .001). Nutritional status (Mini-Nutritional Assessment score) did not differ between groups (pulse; 20.5 ± 4.5, intermediate; 21.0 ± 2.5, spread; 20.5 ± 3.5), nor did any other indices of nutritional status.

CONCLUSIONS

Meeting protein requirements is required before protein distribution may influence nutritional status in institutionalized elderly. Achieving adequate protein and energy intakes is more likely when protein is distributed evenly throughout the day. Provision of high protein foods especially at breakfast, and in the evening, may support protein adequacy and healthy aging, especially for institutionalized elderly.

The Diuretic Action of Weak and Strong Alcoholic Beverages in Elderly Men: A Randomized Diet-Controlled Crossover Trial

With ageing, there is a greater risk of dehydration. This study investigated the diuretic effect of alcoholic beverages varying in alcohol concentration in elderly men. Three alcoholic beverages (beer (AB), wine (AW), and spirits (S)) and their non-alcoholic counterparts (non-alcoholic beer (NAB), non-alcoholic wine (NAW), and water (W)) were tested in a diet-controlled randomized crossover trial. For the alcoholic beverages, alcohol intake equaled a moderate amount of 30 g. An equal volume of beverage was given for the non-alcoholic counterpart. After consumption, the urine output was collected every hour for 4 h and the total 24 h urine output was measured. AW and S resulted in a higher cumulative urine output compared to NAW and W during the first 4 h (effect size: 0.25 mL p < 0.003, effect size: 0.18 mL, p < 0.001, respectively), but not after the 24h urine collection (p > 0.40, p > 0.10). AB and NAB did not differ at any time point (effect size: -0.02 mL p > 0.70). For urine osmolality, and the sodium and potassium concentration, the findings were in line. In conclusion, only moderate amounts of stronger alcoholic beverages, such as wine and spirits, resulted in a short and small diuretic effect in elderly men.

Dose-response effects of supplementation with calcifediol on serum 25-hydroxyvitamin D status and its metabolites: A randomized controlled trial in older adults

BACKGROUND & AIMS

Oral supplementation with vitamin D is recommended for older adults to maintain a sufficient 25-hydroxyvitamin D (25(OH)D) status throughout the year. While supplementation with vitamin D₂ or D₃ is most common, alternative treatment regimens exist which require further investigation with respect to increasing 25(OH)D concentration. We investigated the dose-response effects of supplementation with calcifediol compared to vitamin D₃ and assessed the dose which results in mean serum 25(OH)D₃ concentrations between 75 and 100 nmol/L.

METHODS

This randomized, double-blind intervention study included men and women aged ≥65 years (n = 59). Participants received either 5, 10 or 15 μg calcifediol or 20 μg vitamin D₃ per day, for a period of 24 weeks. Blood samples were collected every four weeks to assess response profiles of vitamin D related metabolites; serum vitamin D₃, 25(OH)D₃, 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) and 24,25-dihydroxyvitamin D₃ (24,25(OH)₂D₃). Further, serum calcium, plasma parathyroid hormone, and urinary calcium were evaluated.

RESULTS

Supplementation with 20 μg vitamin D₃ increased 25(OH)D₃ concentrations towards 70 nmol/L within 16 weeks. Supplementation with 10 or 15 μg calcifediol increased 25(OH)D₃ levels >75 nmol/L in 8 and 4 weeks, respectively. Steady state was achieved from week 12 onwards with serum 25(OH)D₃ levels stabilizing between 84 and 89 nmol/L in the 10 μg calcifediol group. A significant association was observed between the changes in 25(OH)D₃ and 24,25(OH)₂D₃ (R² = 0.83, P < 0.01), but not between 25(OH)D₃ and 1,25(OH)₂D₃ (R² = 0.04, P = 0.18). No cases of hypercalcemia occurred in any treatment during the study period.

CONCLUSIONS

Calcifediol supplementation rapidly and safely elevates serum 25(OH)D₃ concentrations to improve vitamin D status in older adults. A daily dose of 10 μg calcifediol allows serum 25(OH)D₃ concentrations to be maintained between 75 and 100 nmol/L.

TRIAL REGISTRATION NUMBER

NCT01868945.

Translation of a tailored nutrition and resistance exercise intervention for elderly people to a real-life setting: adaptation process and pilot study

BACKGROUND

Combining increased dietary protein intake and resistance exercise training for elderly people is a promising strategy to prevent or counteract the loss of muscle mass and decrease the risk of disabilities. Using findings from controlled interventions in a real-life setting requires adaptations to the intervention and working procedures of healthcare professionals (HCPs). The aim of this study is to adapt an efficacious intervention for elderly people to a real-life setting (phase one) and test the feasibility and potential impact of this prototype intervention in practice in a pilot study (phase two).

METHODS

The Intervention Mapping approach was used to guide the adaptation in phase one. Qualitative data were collected from the original researchers, target group, and HCPs, and information was used to decide whether and how specified intervention elements needed to be adapted. In phase two, a one-group pre-test post-test pilot study was conducted (n = 25 community-dwelling elderly), to elicit further improvements to the prototype intervention. The evaluation included participant questionnaires and measurements at baseline (T0) and follow-up (T1), registration forms, interviews, and focus group discussions (T1). Qualitative data for both phases were analysed using an inductive approach. Outcome measures included physical functioning, strength, body composition, and dietary intake. Change in outcomes was assessed using Wilcoxon signed-rank tests.

RESULTS

The most important adaptations to the original intervention were the design of HCP training and extending the original protein supplementation with a broader nutrition programme aimed at increasing protein intake, facilitated by a dietician. Although the prototype intervention was appreciated by participants and professionals, and perceived applicable for implementation, the pilot study process evaluation resulted in further adaptations, mostly concerning recruitment, training session guidance, and the nutrition programme. Pilot study outcome measures showed significant improvements in muscle strength and functioning, but no change in lean body mass.

CONCLUSION

The combined nutrition and exercise intervention was successfully adapted to the real-life setting and seems to have included the most important effective intervention elements. After adaptation of the intervention using insights from the pilot study, a larger, controlled trial should be conducted to assess cost-effectiveness.

TRIAL REGISTRATION

Trial registration number: ClinicalTrials.gov NL51834.081.14 (April 22, 2015).

The Impact of Dietary Protein or Amino Acid Supplementation on Muscle Mass and Strength in Elderly People: Individual Participant Data and Meta-Analysis of RCT's

OBJECTIVES

Increasing protein or amino acid intake has been promoted as a promising strategy to increase muscle mass and strength in elderly people, however, long-term intervention studies show inconsistent findings. Therefore, we aim to determine the impact of protein or amino acid supplementation compared to placebo on muscle mass and strength in older adults by combining the results from published trials in a meta-analysis and pooled individual participant data analysis.

DESIGN

We searched Medline and Cochrane databases and performed a meta-analysis on eight available trials on the effect of protein or amino acid supplementation on muscle mass and strength in older adults. Furthermore, we pooled individual data of six of these randomized double-blind placebo-controlled trials. The main outcomes were change in lean body mass and change in muscle strength for both the meta-analysis and the pooled analysis.

RESULTS

The meta-analysis of eight studies (n=557) showed no significant positive effects of protein or amino acid supplementation on lean body mass (mean difference: 0.014 kg: 95% CI -0.152; 0.18), leg press strength (mean difference: 2.26 kg: 95% CI -0.56; 5.08), leg extension strength (mean difference: 0.75 kg: 95% CI: -1.96, 3.47) or handgrip strength (mean difference: -0.002 kg: 95% CI -0.182; 0.179). Likewise, the pooled analysis showed no significant difference between protein and placebo treatment on lean body mass (n=412: p=0.78), leg press strength (n=121: p=0.50), leg extension strength (n=121: p=0.16) and handgrip strength (n=318: p=0.37).

CONCLUSIONS

There is currently no evidence to suggest that protein or amino acid supplementation without concomitant nutritional or exercise interventions increases muscle mass or strength in predominantly healthy elderly people.

Reduction in energy expenditure during weight loss is higher than predicted based on fat free mass and fat mass in older adults

BACKGROUND & AIM

The aim of this study was to describe a decrease in resting energy expenditure during weight loss that is larger than expected based on changes in body composition, called adaptive thermogenesis (AT), in overweight and obese older adults.

METHODS

Multiple studies were combined to assess AT in younger and older subjects. Body composition and resting energy expenditure (REE) were measured before and after weight loss. Baseline values were used to predict fat free mass and fat mass adjusted REE after weight loss. AT was defined as the difference between predicted and measured REE after weight loss. The median age of 55 y was used as a cutoff to compare older with younger subjects. The relation between AT and age was investigated using linear regression analysis.

RESULTS

In this study 254 (M = 88, F = 166) overweight and obese subjects were included (BMI: 31.7 ± 4.4 kg/m², age: 51 ± 14 y). The AT was only significant for older subjects (64 ± 185 kcal/d, 95% CI [32, 96]), but not for younger subjects (19 ± 152 kcal/d, 95% CI [-9, 46]). The size of the AT was significantly higher for older compared to younger adults (β = 47, p = 0.048), independent of gender and type and duration of the weight loss program.

CONCLUSIONS

We conclude that adaptive thermogenesis is present only in older subjects, which might have implications for weight management in older adults. A reduced energy intake is advised to counteract the adaptive thermogenesis.

Expression of protocadherin gamma in skeletal muscle tissue is associated with age and muscle weakness

BACKGROUND

The skeletal muscle system plays an important role in the independence of older adults. In this study we examine differences in the skeletal muscle transcriptome between healthy young and older subjects and (pre-)frail older adults. Additionally, we examine the effect of resistance-type exercise training on the muscle transcriptome in healthy older subjects and (pre-)frail older adults.

METHODS

Baseline transcriptome profiles were measured in muscle biopsies collected from 53 young, 73 healthy older subjects, and 61 frail older subjects. Follow-up samples from these frail older subjects (31 samples) and healthy older subjects (41 samples) were collected after 6 months of progressive resistance-type exercise training. Frail older subjects trained twice per week and the healthy older subjects trained three times per week.

RESULTS

At baseline genes related to mitochondrial function and energy metabolism were differentially expressed between older and young subjects, as well as between healthy and frail older subjects. Three hundred seven genes were differentially expressed after training in both groups. Training affected expression levels of genes related to extracellular matrix, glucose metabolism ,and vascularization. Expression of genes that were modulated by exercise training was indicative of muscle strength at baseline. Genes that strongly correlated with strength belonged to the protocadherin gamma gene cluster (r = -0.73).

CONCLUSIONS

Our data suggest significant remaining plasticity of ageing skeletal muscle to adapt to resistance-type exercise training. Some age-related changes in skeletal muscle gene expression appear to be partially reversed by prolonged resistance-type exercise training. The protocadherin gamma gene cluster may be related to muscle denervation and re-innervation in ageing muscle.

The Muscle Metabolome Differs between Healthy and Frail Older Adults

Populations around the world are aging rapidly. Age-related loss of physiological functions negatively affects quality of life. A major contributor to the frailty syndrome of aging is loss of skeletal muscle. In this study we assessed the skeletal muscle biopsy metabolome of healthy young, healthy older and frail older subjects to determine the effect of age and frailty on the metabolic signature of skeletal muscle tissue. In addition, the effects of prolonged whole-body resistance-type exercise training on the muscle metabolome of older subjects were examined. The baseline metabolome was measured in muscle biopsies collected from 30 young, 66 healthy older subjects, and 43 frail older subjects. Follow-up samples from frail older (24 samples) and healthy older subjects (38 samples) were collected after 6 months of prolonged resistance-type exercise training. Young subjects were included as a reference group. Primary differences in skeletal muscle metabolite levels between young and healthy older subjects were related to mitochondrial function, muscle fiber type, and tissue turnover. Similar differences were observed when comparing frail older subjects with healthy older subjects at baseline. Prolonged resistance-type exercise training resulted in an adaptive response of amino acid metabolism, especially reflected in branched chain amino acids and genes related to tissue remodeling. The effect of exercise training on branched-chain amino acid-derived acylcarnitines in older subjects points to a downward shift in branched-chain amino acid catabolism upon training. We observed only modest correlations between muscle and plasma metabolite levels, which pleads against the use of plasma metabolites as a direct read-out of muscle metabolism and stresses the need for direct assessment of metabolites in muscle tissue biopsies.

The effect of exercise training on the course of cardiac troponin T and I levels: three independent training studies

With the introduction of high-sensitive assays, cardiac troponins became potential biomarkers for risk stratification and prognostic medicine. Observational studies have reported an inverse association between physical activity and basal cardiac troponin levels. However, causality has never been demonstrated. This study investigated whether basal cardiac troponin concentrations are receptive to lifestyle interventions such as exercise training. Basal high-sensitive cardiac troponin T (cTnT ) and I (cTnI) were monitored in two resistance-type exercise training programs (12-week (study 1) and 24-week (study 2)) in older adults (≥65 years). In addition, a retrospective analysis for high sensitive troponin I in a 24-week exercise controlled trial in (pre)frail older adults was performed (study 3). In total, 91 subjects were included in the final data analyses. There were no significant changes in cardiac troponin levels over time in study 1 and 2 (study 1: cTnT −0.13 (−0.33–+0.08) ng/L/12-weeks, cTnI −0.10 (−0.33–+0.12) ng/L/12-weeks; study 2: cTnT −1.99 (−4.79–+0.81) ng/L/24-weeks, cTnI −1.59 (−5.70–+2.51) ng/L/24-weeks). Neither was there a significant interaction between training and the course of cardiac troponin in study 3 (p = 0.27). In conclusion, this study provides no evidence that prolonged resistance-type exercise training can modulate basal cardiac troponin levels.

Dietary Protein Intake in Dutch Elderly People: A Focus on Protein Sources

Introduction: Sufficient high quality dietary protein intake is required to prevent or treat sarcopenia in elderly people. Therefore, the intake of specific protein sources as well as their timing of intake are important to improve dietary protein intake in elderly people. Objectives: to assess the consumption of protein sources as well as the distribution of protein sources over the day in community-dwelling, frail and institutionalized elderly people. Methods: Habitual dietary intake was evaluated using 2- and 3-day food records collected from various studies involving 739 community-dwelling, 321 frail and 219 institutionalized elderly people. Results: Daily protein intake averaged 71 ± 18 g/day in community-dwelling, 71 ± 20 g/day in frail and 58 ± 16 g/day in institutionalized elderly people and accounted for 16% ± 3%, 16% ± 3% and 17% ± 3% of their energy intake, respectively. Dietary protein intake ranged from 10 to 12 g at breakfast, 15 to 23 g at lunch and 24 to 31 g at dinner contributing together over 80% of daily protein intake. The majority of dietary protein consumed originated from animal sources (≥60%) with meat and dairy as dominant sources. Thus, 40% of the protein intake in community-dwelling, 37% in frail and 29% in institutionalized elderly originated from plant based protein sources with bread as the principle source. Plant based proteins contributed for >50% of protein intake at breakfast and between 34% and 37% at lunch, with bread as the main source. During dinner, >70% of the protein intake originated from animal protein, with meat as the dominant source. Conclusion: Daily protein intake in these older populations is mainly (>80%) provided by the three main meals, with most protein consumed during dinner. More than 60% of daily protein intake consumed is of animal origin, with plant based protein sources representing nearly 40% of total protein consumed. During dinner, >70% of the protein intake originated from animal protein, while during breakfast and lunch a large proportion of protein is derived from plant based protein sources.

Protein intake and lean body mass preservation during energy intake restriction in overweight older adults

BACKGROUND

Dietary-induced weight loss is generally accompanied by a decline in skeletal muscle mass. The loss of muscle mass leads to a decline in muscle strength and impairs physical performance. A high dietary protein intake has been suggested to allow muscle mass preservation during energy intake restriction.

OBJECTIVE

To investigate the impact of increasing dietary protein intake on lean body mass, strength and physical performance during 12 weeks of energy intake restriction in overweight older adults.

DESIGN

Sixty-one overweight and obese men and women (63±5 years) were randomly assigned to either a high protein diet (HP; 1.7 g kg(-1) per day; n=31) or normal protein diet (NP; 0.9 g kg(-1) per day; n=30) during a 12-week 25% energy intake restriction. During this controlled dietary intervention, 90% of the diet was provided by the university. At baseline and after the intervention, body weight, lean body mass (dual-energy X-ray absorptiometry), leg strength (1-repetition maximum), physical performance (Short Physical Performance Battery, 400 m) and habitual physical activity (actigraph) were assessed.

RESULTS

Body weight declined in both groups with no differences between the HP and NP groups (-8.9±2.9 versus -9.1±3.4 kg, respectively; P=0.584). Lean body mass declined by 1.8±2.2 and 2.1±1.4 kg, respectively, with no significant differences between groups (P=0.213). Leg strength had decreased during the intervention by 8.8±14.0 and 8.9±12.8 kg, with no differences between groups (P=0.689). Physical performance as measured by 400 m walking speed improved in both groups, with no differences between groups (P=0.219).

CONCLUSIONS

Increasing protein intake above habitual intake levels (0.9 g kg(-1) per day) does not preserve lean body mass, strength or physical performance during prolonged energy intake restriction in overweight older adults.