M. Tieland

Low vitamin D status is associated with reduced muscle mass and impaired physical performance in frail elderly people

Background/Objectives:Serum 25-hydroxyvitamin D (25(OH)D) status has been associated with muscle mass, strength and physical performance in healthy elderly people. Yet, in pre-frail and frail elderly people this association has not been studied. The objective of this study was to explore the association between vitamin D intake and serum 25(OH)D status with muscle mass, strength and physical performance in a pre-frail and frail elderly population.Subjects/Methods:This cross-sectional study included 127 pre-frail and frail elderly people in The Netherlands. Whole body and appendicular lean mass (ALM) (dual energy X-ray absorptiometry), leg strength (one repetition maximum), handgrip strength and physical performance (short physical performance battery) were measured, and blood samples were collected for the assessment of serum 25(OH)D status (liquid chromatography-tandem mass spectrometry). In addition, habitual dietary intake (3-day food records) and physical activity data (accelerometers) were collected.Results:In total, 53% of the participants had a serum 25(OH)D level below 50 nmol/l. After adjustment for confounding factors, 25(OH)D status was associated with ALM (β=0.012, P=0.05) and with physical performance (β=0.020, P<0.05). Vitamin D intake was associated with physical performance (β=0.18, P<0.05) but not with ALM (P>0.05).Conclusion:In this frail elderly population, 25(OH)D status is low and suggests a modest association with reduced ALM and impaired physical performance. In addition, vitamin D intake tended to be associated with impaired physical performance. Our findings highlight the need for well-designed intervention trials to assess the impact of vitamin D supplementation on 25(OH)D status, muscle mass and physical performance in pre-frail and frail elderly people.

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.

The impact of 1-year vitamin D supplementation on vitamin D status in athletes: a dose-response study.

Background/Objectives:To assess the prevalence of vitamin D deficiency in Dutch athletes and to define the required dosage of vitamin D3 supplementation to prevent vitamin D deficiency over the course of a year.Subjects/Methods:Blood samples were collected from 128 highly trained athletes to assess total 25(OH)D concentration. Of these 128 athletes, 54 male and 48 female athletes (18–32 years) were included in a randomized, double blind, dose–response study. Athletes with either a deficient (<50 nmol/l) or an insufficient (50–75 nmol/l) 25(OH)D concentration were randomly assigned to take 400, 1100 or 2200 IU vitamin D3 per day orally for 1 year. Athletes who had a total 25(OH)D concentration above 75 nmol/l at baseline continued with the study protocol without receiving vitamin D supplements. Serum total 25(OH)D concentration was assessed every 3 months, as well as dietary vitamin D intake and sunlight exposure.Results:Nearly 70% of all athletes showed an insufficient (50–75 nmol/l) or a deficient (<50 nmol/l) 25(OH)D concentration at baseline. After 12 months, serum 25(OH)D concentration had increased more in the 2200 IU/day group (+50±27 nmol/l) than the sufficient group receiving no supplements (+4±17 nmol/l; P<0.01) and the 1100 IU/day group (+25±23 nmol/l; P<0.05). Supplementation with 2200 IU/day vitamin D resulted in a sufficient 25(OH)D concentration in 80% of the athletes after 12 months.Conclusions:Vitamin D deficiency is highly prevalent in athletes. Athletes with a deficient or an insufficient 25(OH)D concentration can achieve a sufficient 25(OH)D concentration within 3 months by taking 2200 IU/day.

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‐1&bgr;, IL‐6, IL‐8 and TNF‐&agr; 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‐&agr;. However, exercise training led to a small but significant increase of 0.052 pg/mL in IL‐1&bgr;. Higher circulating levels of TNF‐&agr;, IL‐8 and IL‐6 during the training period were negatively associated with strength gains for the leg press. A doubling of plasma TNF‐&agr;, 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‐&agr; 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‐&agr;, IL‐6 and IL‐8) are associated with lower strength gains during resistance exercise training.

Digitally supported dietary counseling increases protein intake in community dwelling older adults: Preliminary results of the vitamin RCT

BACKGROUND. In order to prevent sarcopenia in community dwelling older adults a higher daily protein intake is needed. A new e-health strategy for dietary counseling was used with the aim to increase total daily protein intake to optimal levels (minimal 1.2 g/kg/d, optimal 1.5 g/kg/d) through use of regular food products.METHODS. The VITAMIN (VITal AMsterdam older adults IN the city) RCT included 245 community dwelling older adults (age ≥ 55y): control, exercise, and exercise plus dietary counseling (protein) group. Dietary intake was measured by a 3d dietary record at baseline and after 6 months intervention. In total 173 subjects were eligible for analysis. A two-way mixed ANOVA with time, group, and time*group interaction was performed. Post-hoc Bonferroni was performed with significance level at p<0.05.RESULTS. Mean age of the subjects was 72.1±6.3y, with a BMI of 25.7±4.2 of which 68% were females. ANOVA revealed significant effect of time, group and time*group (p<0.001). Table 1 shows higher protein intake over time in the dietary counseling group than either control (p=0.038) or exercise (p=0.008) group. Additional analyses revealed no change in vegetable protein intake. The higher protein intake was fully accounted for by animal protein intake. In the dietary counseling group 72% of subjects increased protein intake above the minimum intake level. DISCUSSION. This study shows digitally supported dietary counseling improves protein intake sufficiently in community dwelling older adults. Protein intake increase by counseling with e-health is a promising strategy for dieticians with the upcoming rising ageing population.