Insulin resistance, cognition, and functional brain network topology in older adults with obesity.

Objective: Cross-sectional data from a sample of older adults with obesity was used to determine how peripheral and neuronal insulin resistance (IR) relate to executive function and functional brain network topology.

Methods: Older adults (n=71) with obesity but without type 2 diabetes were included. Peripheral IR was quantified by HOMA2-IR.

Neural Determinants of Sedentary Lifestyle in Older Adults: A Brain Network Analysis.

Purpose: The prevalence of sedentary lifestyles (SL), which includes both high volumes of extended sitting behavior and a low volume of steps accumulated across the day, among older adults continues to rise contributing to increases in associated comorbidities and the loss of independence. The social, personal, and economic burdens are enormous. In recognition of the health implications of SL, current public health physical activity guidelines now emphasize the complimentary goals of sitting less by moving more.

Sex differences in the association between skeletal muscle energetics and perceived physical fatigability: the Study of Muscle, Mobility and Aging (SOMMA).

Greater perceived physical fatigability and lower skeletal muscle energetics are both predictors of mobility decline. Characterizing associations between muscle energetics and perceived fatigability may provide insight into potential targets to prevent mobility decline. We examined associations of in vivo (maximal ATP production, ATPmax) and ex vivo (maximal carbohydrate supported oxidative phosphorylation [max OXPHOS] and maximal fatty acid supported OXPHOS [max FAO OXPHOS]) measures of mitochondrial energetics with two measures of perceived physical fatigability, Pittsburgh Fatigability Scale (PFS, 0-50, higher = greater) and Rating of Perceived Exertion (RPE Fatigability, 6-20, higher = greater) after a slow treadmill walk.

The Bone, Exercise, Alendronate, and Caloric Restriction (BEACON) trial design and methods.

Background: Among older adults living with obesity, intentional weight loss (WL) improves prognosis of many comorbidities. However, concomitant decline in bone mineral density (BMD) limits overall benefit of WL by increasing osteoporotic fracture risk. Identification of intervention strategies to maximize body fat loss, while minimizing harm to the musculoskeletal system, is an important area of clinical research.

Role of Walking Energetics and Perceived Fatigability Differs by Gait Speed: The Study of Muscle, Mobility and Aging (SOMMA).

Background: Slower gait speed may be driven by greater energy deficits and fatigability among older adults. We examined associations of walking energetics and perceived physical fatigability with gait speed among slower and faster walkers. Additionally, we used statistical mediation to examine the role of fatigability in the associations of walking energetics and gait speed using the Study of Muscle, Mobility and Aging (SOMMA).