A "NEAT" Approach to Obesity Prevention in the Modern Work Environment.

Increased prevalence of obesity may be due to an increase of being sedentary at work. Increasing non-exercise activity thermogenesis (NEAT) using walking workstations may increase total physical activity and promote a leaner physical body composition (or phenotype). The purpose of this study was to test whether walking slowly during work was sufficient to promote a leaner phenotype by increasing physical activity in sedentary desk workers without inducing compensation or a decrease in activity or energy expenditure during the nonworking hours. We conducted a prospective cohort study using a within-subjects crossover design. The design involved two phases each lasting 2 weeks: a treadmill exercise phase in which subjects used a walking workstation for 2.5 hours a day 5 days/week and a control phase in which subjects maintained their normal work activity. Twenty-five sedentary adults working at the Minneapolis VA Health Care System. We measured body weight, body composition, food intake, 24-hour physical activity, and self-reported physical activity with the International Physical Activity Questionnaire (IPAQ). Treadmill exercise caused a leaner phenotype (lean mass gain and fat mass loss) and significantly increased their 24-hour physical activity. Walking workstation use had favorable effects on physical well-being and mental focus and did not adversely affect productivity. Light treadmill exercise during work can increase physical activity and result in a leaner body composition. This is a potentially useful intervention to increase NEAT in the modern sedentary work environment.

Effect of Housing Types on Growth, Feeding, Physical Activity, and Anxiety-Like Behavior in Male Sprague-Dawley Rats.

BACKGROUND: Animal welfare and accurate data collection are equally important in rodent research. Housing influences study outcomes and can challenge studies that monitor feeding, so housing choice needs to be evidence-based. The goal of these studies was to (1) compare established measures of well-being between rodents housed in wire grid-bottom floors with a resting platform compared to solid-bottom floors with bedding and (2) determine whether presence of a chewable device (Nylabone) affects orexin-A-induced hyperphagia. METHODS: Rodents were crossed over to the alternate housing twice after 2-week periods. Time required to complete food intake measurements was recorded as an indicator of feasibility. Food intake stimulated by orexin-A was compared with and without the Nylabone. Blood corticosterone and hypothalamic BDNF were assessed. RESULTS: Housing had no effect on growth, energy expenditure, corticosterone, hypothalamic BDNF, behavior, and anxiety measures. Food intake was disrupted after housing cross-over. Time required to complete food intake measurements was significantly higher for solid-bottom bedded cages. The Nylabone had no effect on orexin-A-stimulated feeding. CONCLUSION: Well-being is not significantly different between rodents housed on grid-bottom floors and those in solid-bottom-bedded cages based on overall growth and feeding but alternating between housing confounds measures of feeding.

The orexin neuropeptide system: physical activity and hypothalamic function throughout the aging process.

There is a rising medical need for novel therapeutic targets of physical activity. Physical activity spans from spontaneous, low intensity movements to voluntary, high-intensity exercise. Regulation of spontaneous and voluntary movement is distributed over many brain areas and neural substrates, but the specific cellular and molecular mechanisms responsible for mediating overall activity levels are not well understood. The hypothalamus plays a central role in the control of physical activity, which is executed through coordination of multiple signaling systems, including the orexin neuropeptides. Orexin producing neurons integrate physiological and metabolic information to coordinate multiple behavioral states and modulate physical activity in response to the environment. This review is organized around three questions: (1) How do orexin peptides modulate physical activity? (2) What are the effects of aging and lifestyle choices on physical activity? (3) What are the effects of aging on hypothalamic function and the orexin peptides? Discussion of these questions will provide a summary of the current state of knowledge regarding hypothalamic orexin regulation of physical activity during aging and provide a platform on which to develop improved clinical outcomes in age-associated obesity and metabolic syndromes.