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Instrumenting the six-minute walk test (6MWT) adds information about gait quality and insight into fall risk. Being physically active and preserving multi-directional stepping abilities are also important for fall risk reduction. This analysis investigated the relationship of gait quality during the 6MWT with physical functioning and physical activity. Twenty-one veterans (62.2 ± 6.4 years) completed the four square step test (FSST) multi-directional stepping assessment, a gait speed assessment, health questionnaires, and the accelerometer-instrumented 6MWT. An activity monitor worn at home captured free-living physical activity. Gait measures were not significantly different between minutes of the 6MWT. However, participants with greater increases in stride time (ρ = −0.594, p < 0.01) and stance time (ρ = −0.679, p < 0.01) during the 6MWT reported lower physical functioning. Neither physical activity nor sedentary time were related to 6MWT gait quality. Participants exploring a larger range in stride time variability (ρ = 0.614, p < 0.01) and stance time variability (ρ = 0.498, p < 0.05) during the 6MWT required more time to complete the FSST. Participants needing at least 15 s to complete the FSST meaningfully differed from those completing the FSST more quickly on all gait measures studied. Instrumenting the 6MWT helps detect ranges of gait performance and provides insight into functional limitations missed with uninstrumented administration. Established FSST cut points identify aging adults with poorer gait quality. [ABSTRACT FROM AUTHOR]

Myosteatosis, or the infiltration of fatty deposits into skeletal muscle, occurs with advancing age and contributes to the health and functional decline of older adults. Myosteatosis and its inflammatory milieu play a larger role in adipose tissue dysfunction, muscle tissue dysfunction, and increased passive muscle stiffness. Combined with the age‐related decline of sex hormones and development of anabolic resistance, myosteatosis also contributes to insulin resistance, impaired muscle mechanics, loss of force production from the muscle, and increased risk of chronic disease. Due to its highly inflammatory secretome and the downstream negative effects on muscle metabolism and mechanics, myosteatosis has become an area of interest for aging researchers and clinicians. Thus far, myosteatosis treatments have had limited success, as many lack the potency to completely rescue the metabolic and physical consequences of myosteatosis. Future research is encouraged for the development of reliable assessment methods for myosteatosis, as well as the continued exploration of pharmacological, nutritional, and exercise‐related interventions that may lead to the success in attenuating myosteatosis and its clinical consequences within the aging population. [ABSTRACT FROM AUTHOR]

The aim of the present study was to develop a standardized contrast-enhanced duplex ultrasound (CE-DUS) protocol to assess lower-extremity muscle perfusion before and after exercise and determine relationships of perfusion with clinical and functional measures. CE-DUS (EPIQ 5G, Philips) was used before and immediately after a 10-minute, standardized bout of treadmill walking to compare microvascular perfusion of the gastrocnemius muscle in older (55-82 years) patients with peripheral arterial disease (PAD) (n = 15, mean ankle-brachial index, 0.78 ± 0.04) and controls (n = 13). Microvascular blood volume (MBV) and microvascular flow velocity (MFV) were measured at rest and immediately following treadmill exercise, and the Modified Physical Performance Test (MPPT) was used to assess mobility function. In the resting state (pre-exercise), MBV in patients with PAD was not significantly different than normal controls (5.17 ± 0.71 vs 6.20 ± 0.83 arbitrary units (AU) respectively; P =.36); however, after exercise, MBV was ∼40% lower in patients with PAD compared with normal controls (5.85 ± 1.13 vs 9.53 ± 1.31 AU, respectively; P =.04). Conversely, MFV was ∼60% higher in patients with PAD compared with normal controls after exercise (0.180 ± 0.016 vs 0.113 ± 0.018 AU, respectively; P =.01). There was a significant between-group difference in the exercise-induced changes in both MBV and MFV (P ≤.05). Both basal and exercise MBV directly correlated with MPPT score in the patients with PAD (r = 0.56-0.62; P <.05). This standardized protocol for exercise stress testing of the lower extremities quantifies calf muscle perfusion and elicits perfusion deficits in patients with PAD. This technique objectively quantifies microvascular perfusion deficits that are related to reduced mobility function and could be used to assess therapeutic efficacy in patients with PAD. [ABSTRACT FROM AUTHOR]

Background and Purpose: Sarcopenic obesity is associated with loss of independence among older adults, but the epidemiology of sarcopenic obesity and associated geriatric vulnerabilities are poorly understood. Thus, our objectives were to: (1) estimate the prevalence of older adults with sarcopenic obesity and (2) examine rates of geriatric vulnerabilities among obese older adults, with and without sarcopenia. Methods: A nationally representative sample of 1600 community-dwelling older adults 65 years and older with obesity and documented measures of muscle function from the National Health and Aging Trends Study (NHATS) was identified as sarcopenic using sex-adjusted grip strength and Short Physical Performance Battery scores. Differences in the prevalence of geriatric vulnerabilities (including pain, depression, disability, and social isolation) were compared between obese older adults with and without sarcopenia. Results and Discussion: Among obese older adults, 18% (n = 318/1600) were sarcopenic. After adjusting for age and sex, sarcopenic obese older adults had 3.7 times the odds of having 2 or more comorbid conditions (odds ratio [OR] = 3.7; 95% CI 2.2-5.0) and 6.4 times the odds of being frail (OR = 6.4; 95% CI 4.4-9.5) as compared with nonsarcopenic obese older adults. Sarcopenic obese older adults were also more likely to have 1 or more activities of daily living disabilities (OR = 3.7; 95% CI 2.5-5.4), be socially isolated (OR = 2.1; 95% CI 1.3-3.2), and report activity-limiting pain (OR = 2.0; 95% CI 1.5-2.7) as compared with nonsarcopenic obese older adults. These findings, in a nationally representative cohort, suggest obese older adults who are sarcopenic have higher rates of geriatric vulnerabilities that could impact delivery and outcomes of exercise and nutrition interventions. Conclusions: Concomitant obesity and sarcopenia are associated with higher rates of geriatric vulnerabilities among a nationally representative sample of older adults. More comprehensive interventions, beyond exercise and diet modifications, may be necessary to additionally address these newly identified social and physiological risks. [ABSTRACT FROM AUTHOR]

Veterans represent a unique population of older adults, as they are more likely to self-report a disability and be overweight or obese compared with the general population. We sought to compare changes in mobility function across the obesity spectrum in older veterans participating in 6 months of Gerofit, a clinical exercise program. A total of 270 veterans (mean age: 74 years) completed baseline, 3-, and 6-month mobility assessments and were divided post hoc into groups: normal weight, overweight, and obese. The mobility assessments included 10-m walk time, 6-min walk distance, 30-s chair stands, and 8-foot up-and-go time. No significant weight x time interactions were found for any measure. However, clinically significant improvements of 7-20% were found for all mobility measures from baseline to 3 months and maintained at 6 months (all ps < .05). Six months of participation in Gerofit, if enacted nationwide, appears to be one way to improve mobility in older veterans at high risk for disability, regardless of weight status. [ABSTRACT FROM AUTHOR]