Dylan R. Kirn

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.

What is a Clinically Meaningful Improvement in Leg-Extensor Power for Mobility-limited Older Adults?

BACKGROUND Muscle power is a key predictor of physical function in older adults; however, clinically meaningful improvements in leg-extensor muscle power have yet to be identified. The purpose of this study is to establish the minimal clinically important improvement (MCII) and substantial improvement (SI) for leg-extensor power and muscle contraction velocity in mobility-limited older adults. METHODS Data were extracted from three randomized trials of leg-extensor muscle power training interventions (3- to 6-month duration). Measurements of leg-extensor power and velocity were obtained using dynamic bilateral leg press at 40% and 70% of the one-repetition maximum. Anchor-based MCIIs were calculated using selected items extracted from the Late Life Function and Disability Instrument. Standard error of measurement and effect size methods were used to calculate the distribution-based MCII. RESULTS Data from 164 participants (mean age: 76.6 ± 5.6 years; Short Physical Performance Battery score: 7.8 ± 1.3) were used in this analysis. The respective MCII and SI estimates for 40% leg-extensor power were 18.3 (9%) and 30.5 (15%) W, and 23.1 (10%) and 41.6 (18%) W for 70% leg-extensor power. The respective MCII and SI estimates for 40% average velocity were 0.03(7%) and 0.08(18%) m/s, and 0.02(6%) and 0.05(15%) m/s for 70% average velocity. CONCLUSIONS This is the first study to establish a clinically meaningful improvement of leg-extensor power (9%-10%) and velocity (6%-7%) in mobility-limited older adults. These findings should be used to aid in the design and interpretation of clinical trials and interventions that target improvements in muscle power in this high-risk population.

Recruitment of Mobility Limited Older Adults Into a Facility-Led Exercise-Nutrition Study: The Effect of Social Involvement

PURPOSE OF THE STUDY Older adults are among the most challenging population groups to enroll into health-related research. This article describes two methods used by investigators to recruit mobility limited older adults residing at assisted living or senior housing (SH) facilities into a facility-led exercise-nutrition research study. DESIGN AND METHODS Sedentary older adults were recruited from 42 different assisted living facilities (ALFs) or SH communities. Two different recruitment approaches were used: At 22 sites, investigators conducted heavily advertised informational sessions to recruit participants (Info only). At 20 locations, these sessions were preceded by attendance of a study team member at various activities offered by the facility over the preceding 2 weeks (activity attendance). Population reach, enrollment, personnel cost, and time required to recruit at least five participants at each facility was measured. Reasons for declining participation and withdrawal rate were also measured. RESULTS Sixty percent more residents elected to be screened for eligibility when study personnel attended an activity offered by the facility. Activity attendance resulted in significantly less time, costs, and participant withdrawals compared with facilities with no activity attendance. IMPLICATIONS Study team member attendance at activities offered by senior living facilities reduces cost and duration of recruitment and improves study retention. Interventions targeting this demographic are likely to benefit from deliberately building trust and familiarity among the resident population at senior living communities as part of the recruitment process.

Accelerometer Assessment of Physical Activity and Its Association with Physical Function in Older Adults Residing at Assisted Care Facilities.

ObjectivesTo describe levels of physical activity among older adults residing at assisted care facilities and their association with physical function.DesignCross-sectional analysis.SettingAssisted care facilities within the greater Boston, MA area.ParticipantsOlder adults aged 65 years and older (N = 65).MeasurementsPhysical Activity Level (PAL) as defined by quartiles from accelerometry (counts and steps), Short Physical Performance Battery (SPPB) Score, gait speed, and handgrip strength.ResultsParticipants in the most active accelerometry quartile engaged in 25 minutes/week of moderate to vigorous physical activity (MVPA) and walked 2,150 steps/day. These individuals had an SPPB score, 400 meter walk speed, and handgrip strength that was 3.7–3.9 points, 0.3–0.4 meters/second, and 4.5–5.1 kg greater respectively, than individuals in the lowest activity quartile, who engaged in less than 5 min/wk of MVPA or took fewer than 460 steps/day.ConclusionDespite engaging in physical activity levels far below current recommendations (150 min/week of MVPA or > 7000 steps/day), the most active older adults in this study exhibited clinically significant differences in physical function relative to their less active peers. While the direction of causality cannot be determined from this cross-sectional study, these findings suggest a strong association between PAL and physical function among older adults residing in an assisted care facility.

The Vitality, Independence, and Vigor in the Elderly 2 Study (VIVE2): Design and methods

BACKGROUND Nutritional supplementation may potentiate the increase in skeletal muscle protein synthesis following exercise in healthy older individuals. Whether exercise and nutrition act synergistically to produce sustained changes in physical functioning and body composition has not been well studied, particularly in mobility-limited older adults. METHODS The VIVE2 study was a multi-center, randomized controlled trial, conducted in the United States and Sweden. This study was designed to compare the effects of a 6-month intervention with a once daily, experimental, 4 fl.oz. liquid nutritional supplement providing 150 kcal, whey protein (20 g), and vitamin D (800 IU) (Nestlé Health Science, Vevey, Switzerland), to a low calorie placebo drink (30 kcal, non-nutritive; identical format) when combined with group-based exercise in 150 community-dwelling, mobility-limited older adults. All participants participated in a structured exercise program (3 sessions/week for 6 months), which included aerobic, strength, flexibility, and balance exercises. RESULTS The primary outcome was 6-month change in 400 m walk performance (m/s) between supplement and placebo groups. Secondary outcomes included 6 month change in: body composition, muscle cross-sectional area, leg strength, grip strength, stair climb time, quality of life, physical performance, mood/depressive symptoms and nutritional status. These outcomes were selected based on their applicability to the health and well-being of older adults. CONCLUSIONS The results of this study will further define the role of nutritional supplementation on physical functioning and restoration of skeletal muscle mass in older adults. Additionally, these results will help refine the current physical activity and nutritional recommendations for mobility-limited older adults.

Serum Predictors of Percent Lean Mass in Young Adults.

Abstract Lustgarten, MS, Price, LL, Phillips, EM, Kirn, DR, Mills, J, and Fielding, RA. Serum predictors of percent lean mass in young adults. J Strength Cond Res 30(8): 2194–2201, 2016—Elevated lean (skeletal muscle) mass is associated with increased muscle strength and anaerobic exercise performance, whereas low levels of lean mass are associated with insulin resistance and sarcopenia. Therefore, studies aimed at obtaining an improved understanding of mechanisms related to the quantity of lean mass are of interest. Percent lean mass (total lean mass/body weight × 100) in 77 young subjects (18–35 years) was measured with dual-energy x-ray absorptiometry. Twenty analytes and 296 metabolites were evaluated with the use of the standard chemistry screen and mass spectrometry–based metabolomic profiling, respectively. Sex-adjusted multivariable linear regression was used to determine serum analytes and metabolites significantly (p ⩽ 0.05 and q ⩽ 0.30) associated with the percent lean mass. Two enzymes (alkaline phosphatase and serum glutamate oxaloacetate aminotransferase) and 29 metabolites were found to be significantly associated with the percent lean mass, including metabolites related to microbial metabolism, uremia, inflammation, oxidative stress, branched-chain amino acid metabolism, insulin sensitivity, glycerolipid metabolism, and xenobiotics. Use of sex-adjusted stepwise regression to obtain a final covariate predictor model identified the combination of 5 analytes and metabolites as overall predictors of the percent lean mass (model R2 = 82.5%). Collectively, these data suggest that a complex interplay of various metabolic processes underlies the maintenance of lean mass in young healthy adults.

Effect of structured physical activity and nutritional supplementation on physical function in mobility-limited older adults: Results from the VIVE2 randomized trial

ObjectivesThe interactions between nutritional supplementation and physical activity on changes in physical function among older adults remain unclear. The primary objective of this study was to examine the impact of nutritional supplementation plus structured physical activity on 400M walk capacity in mobility-limited older adults across two sites (Boston, USA and Stockholm, Sweden).DesignAll subjects participated in a physical activity program (3x/week for 24 weeks), involving walking, strength, balance, and flexibility exercises. Subjects were randomized to a daily nutritional supplement (150kcal, 20g whey protein, 800 IU vitamin D) or placebo (30kcal, non-nutritive).SettingParticipants were recruited from urban communities at 2 field centers in Boston MA USA and Stockholm SWE.ParticipantsMobility-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.MeasurementsPrimary outcome was gait speed assessed by the 400M walk. Results: 149 subjects were randomized into the study (mean age=77.5±5.4; female=46.3%; mean SPPB= 7.9±1.2; mean 25(OH)D=18.7±6.4 ng/ml). Adherence across supplement and placebo groups was similar (86% and 88%, respectively), and was also similar across groups for the physical activity intervention (75% and 72%, respectively). Both groups demonstrated an improvement in gait speed with no significant difference between those who received the nutritional supplement compared to the placebo (0.071 and 0.108 m/s, respectively (p=0.06)). Similar effects in physical function were observed using the SPPB. Serum 25(OH)D increased in supplemented group compared to placebo 7.4 ng/ml versus 1.3 ng/ml respectively.ConclusionResults suggest improved gait speed following physical activity program with no further improvement with added nutritional supplementation.

Physical performance and serum 25(OH)vitamin D status in community dwelling old mobility limited adults: A cross-sectional study

ObjectivesTo examine the potential association between serum 25(OH) vitamin D and the performance on the Short Physical Performance Battery (SPPB) including the sub-components; five repeated chair stands test, 4 meters walk test and balance in older mobility-limited community-dwelling men and women.DesignA cross sectional study was performed in American and Swedish subjects who were examined for potential participation in a combined exercise and nutrition intervention trial. Logistic regression analysis and linear regression analyses were performed to evaluate the association for 25(OH)D with the overall score on the SBBP, chair stand, gait speed and balance.ParticipantsCommunity-dwelling (mean age 77.6 ± 5.3 years) mobility limited American (n=494) and Swedish (n=116) females (59%) and males.MeasurementsThe SPPB (0-12 points) includes chair stand (s), gait speed (m/s) and a balance test. Mobility limitation i.e., SPPB score ≤ 9 was an inclusion criterion. A blood sample was obtained to measure serum 25(OH)vitamin D concentrations.ResultsNo clear association of 25(OH)D with SPPB scores was detected either when 25(OH)D was assessed as a continuous variable or when categorized according to serum concentrations of <50, 50-75 or <75 nmol/L. However, when analyzing the relationship between 25(OH)D and seconds to perform the chair stands, a significant quadratic relationship was observed. Thus, at serum levels of 25(OH)D above 74 nmol/L, higher concentrations appeared to be advantageous for the chair stand test, whereas for serum levels below 74 nmol/L this association was not observed.ConclusionThis cross- sectional study lacked clear association between serum 25(OH)D and physical performance in mobility limited adults. A potentially interesting observation was that at higher serum levels of 25(OH)D a better performance on the chair stand test was indicated.

“Feeling More Self-Confident, Cheerful and Safe”. Experiences from a Health-Promoting Intervention in Community Dwelling Older Adults — A Qualitative Study

ObjectivesStudies show that regular exercise in combination with nutritional support can be effective in managing sarcopenia, which is age-related involuntary loss of skeletal muscle mass and strength. Qualitative investigations of participants’ experiences from interventions in this domain are scarce. In this study, we explored older persons’ experiences from an intervention designed to prevent sarcopenia, with the aim of capturing the participants’ thoughts and opinions.DesignA qualitative study embedded in the multicenter randomized clinical trial The Vitality and Vigor in the Elderly study, VIVE2. Focus group interviews were conducted. Manifest and latent content analyses were performed.ParticipantsCommunity dwelling older adults (n=20) 71-86 years of age with minor limitations in mobility.ResultsThe experiences from the intervention were categorized and interpreted in one overall theme “Feeling more self-confident, cheerful and safe”. The theme encompasses the categories psychological effects of participating in the intervention, physical effects of participating in the intervention, the importance of social support and the importance of a tailored set-up. The participants described their motives for participating in the intervention as being based on concerns regarding the negative health effects of continuing a sedentary lifestyle, difficulties of getting started on their own and lack of confidence in accomplishing change on their own. Participants also expressed that one main objective for participating was to lose weight.ConclusionIn this study we have captured the experiences of older adults with minor mobility limitations who participated in a lifestyle intervention. The experiences are interpreted in one overall theme “Feeling more self-confident, cheerful and safe”. The central understanding of the participants’ experiences was that the intervention affected them in several ways, both psychologically and physically, and that supporting factors included the social support, which became a prerequisite for success. A noticeable finding was the discrepancy between the motive of the participants, to lose weight, and the aim of the study, to improve muscle function. The expectation to lose weight seems to reflect what is commonly known as to be healthy. To our knowledge, at least in Sweden, there are no campaigns or public information highlighting the risks of sarcopenia and the complex issue of if, and when weight loss is desirable for older individuals. This finding highlights the importance of providing such information to this target group. The findings in this study provide valuable knowledge for research teams, practitioners and decision makers when designing and setting objectives for health-promoting interventions for older individuals.

Translating the Lifestyle Interventions and Independence for Elders Clinical Trial to Older Adults in a Real-World Community-Based Setting

BACKGROUND The Lifestyle Interventions and Independence for Elders (LIFE) clinical trial demonstrated that a structured program of physical activity (PA) reduced mobility-disability in older adults by up to 28%. It remains unknown whether the benefits of LIFE PA can be translated to older adults at risk for mobility-disability in real-world community-based settings. To address this knowledge gap, we conducted the ENhancing independence using Group-based community interventions for healthy AGing in Elders (ENGAGE) pilot study and examined the safety, feasibility, and preliminary effectiveness of translating LIFE PA to a community-based senior center. METHODS Forty older adults with severe lower extremity functional limitations (age: 76.9 ± 7.3 years; body mass index: 32.7 ± 8 kg/m2; 85% female; short physical performance battery score: 6.3 ± 2.2) were randomized to 24 weeks of PA or a health education control intervention. RESULTS Community-based PA was safe (serious adverse events: PA vs health education, 0:2; nonserious adverse events: PA vs health education, 3:1) and participants successfully adhered to the PA intervention (65.2%). Compared to health education, PA participants who attended ≥25% of scheduled visits had meaningful and sustained short physical performance battery improvements at follow-up (between group short physical performance battery score differences: ~0.7 units). CONCLUSIONS ENGAGE has demonstrated the preliminary safety, feasibility, and effectiveness of LIFE PA in a real-world community-based setting. Larger-scale translational studies are needed to further disseminate the benefits of LIFE PA to vulnerable older adults in a variety of community-based settings.