Assessing Moderate to Vigorous Physical Activity in Older Adults: Validity of a Commercial Activity Tracker.

Purpose: Despite the potential for commercial activity devices to promote moderate to vigorous physical activity (MVPA), limited information is available in older adults, a high-priority target population with unique gait dynamics and energy expenditure. The study purpose was to investigate the content validity of the Garmin Vivosmart HR device for step counts and MVPA in adults ≥65 years of age in free-living conditions. Methods: Thirty-five participants (M age= 73.7 (6.3) years) wore Garmin and ActiGraph GT3X+ devices for a minimum of 2 days. Accuracy and intra-person reliability were tested against a hip worn ActiGraph device. Separate analyses were conducted using different accelerometer cut-off values to define MVPA, a population-based threshold (≥2,020 counts/minute) and a recommended threshold for older adults (≥1,013 counts/minute). Results: Overall, the Garmin device overestimated MVPA compared with the hip-worn ActiGraph. However, the difference was small using the lower, age-specific, MVPA cut-off value [median (IQR) daily minutes; 50(85) vs. 32(49), p = 0.35] in contrast to the normative standard (50(85) vs. 7(24), p < 0.001). Regardless of the MVPA cut-off, intraclass correlation showed poor reliability [ICC (95% CI); 0.16(-0.40, 0.55) to 0.35(-0.32, 0.7)] which was supported by Bland-Altman plots. Garmin step count was both accurate (M step difference: 178.0, p = 0.22) and reliable [ICC (95% CI; 0.94) (0.88, 0.97)]. Conclusion: Results support the accuracy of a commercial activity device to measure MVPA in older adults but further research in diverse patient populations is needed to determine clinical utility and reliability over time.

Short Communication: Low Muscle Mass Is Associated with Osteoporosis in Older Adults Living with HIV.

Sarcopenia, age-related low muscle mass and function, is a well-established independent risk factor for bone fracture in the geriatric population but is understudied in older people living with HIV (PLWH). The objective of this cross-sectional study was to investigate in older PLWH the relationship between muscle mass and bone mineral density (BMD). Sedentary PLWH who were ≥50 years of age, receiving antiretroviral therapy, and enrolled in an exercise intervention trial were included. Established definitions for sarcopenia and osteopenia/osteoporosis were applied to muscle mass data and BMD collected by dual-energy X-ray absorptiometry before exercise training. Participants were 93% male and 33% Caucasian race with median age 61 years, and median CD4 lymphocytes 707 cells/µL. The majority (64%) were overweight and obese by body mass index. Appendicular skeletal muscle index (ASMI) correlated with BMD at the femoral neck (r = 0.49, p < .01), total hip (r = 0.54, p < .01), and lumbar spine (r = 0.48, p < .05). Low BMD at the femoral neck was present in 39% (26% osteopenia, 13% osteoporosis). ASMI was lower among those with low BMD compared with normal BMD (p = .02). Low muscle mass measured by ASMI is associated with low BMD in clinically stable older PLWH. Detailed body composition assessment may help guide lifestyle recommendations to prevent bone fractures in older PLWH.

Mobility Improvements are Found in Older Veterans After 6-Months of Gerofit Regardless of BMI Classification.

Veterans represent a unique population of older adults as they are more likely to self-report disability and be overweight or obese compared to the general population. We sought to compare changes in mobility function across the obesity spectrum in older Veterans participating in six-months of Gerofit, a clinical exercise program. 270 Veterans completed baseline, three, and six-month functional assessment and were divided post-hoc into groups: normal weight, overweight, and obese. Physical function assessment included: ten-meter walk time, six-minute walk distance, 30-second chair stands, and eight-foot up-and-go time. No significant weight x time interactions were found for any measure. However, significant (P<0.02) improvements were found for all mobility measures from baseline to three-months and maintained at six-months. Six-months of participation in Gerofit, if enacted nationwide, appears to be one way to improve mobility and function in older Veterans at high risk for disability regardless of weight status.

Should Structured Exercise Be Promoted As a Model of Care? Dissemination of the Department of Veterans Affairs Gerofit Program.

Exercise provides a wide range of health-promoting benefits, but support is limited for clinical programs that use exercise as a means of health promotion. This stands in contrast to restorative or rehabilitative exercise, which is considered an essential medical service. We propose that there is a place for ongoing, structured wellness and health promotion programs, with exercise as the primary therapeutic focus. Such programs have long-lasting health benefits, are easily implementable, and are associated with high levels of participant satisfaction. We describe the dissemination and implementation of a long-standing exercise and health promotion program, Gerofit, for which significant gains in physical function that have been maintained over 5 years of follow-up, improvements in well-being, and a 10-year 25% survival benefit among program adherents have been documented. The program has been replicated at 6 Veterans Affairs Medical Centers. The pooled characteristics of enrolled participants (n = 691) demonstrate substantial baseline functional impairment (usual gait speed 1.05 ± 0.3 m/s, 8-foot up and go 8.7 ± 6.7 seconds, 30-second chair stands 10.7 ± 5.1, 6-minute walk distance 404.31 ± 141.9 m), highlighting the need for such programs. Change scores over baseline for 3, 6, and 12 months of follow-up are clinically and statistically significant (P < .05 all measures) and replicate findings from the parent program. Patient satisfaction ratings of high ranged from 88% to 94%. We describe the implementation process and present 1-year outcomes. We suggest that such programs be considered essential elements of healthcare systems.

Providing Rural Veterans With Access to Exercise Through Gerofit.

Clinical video telehealth can be used to deliver functional circuit exercise training to older veterans in remote locations.