Grant: Operating Grant - Priority Announcement: Aging (Bridge Funding)

Background: Aging, obesity, and obesity related health problems (ie, type 2 diabetes, metabolic syndrome, inflammation profile, etc.) have been associated with mobility problems in older individuals. A few well-controlled studies using exercise with or without intentional caloric restriction (CR) have investigated the effectiveness of these approaches on mobility and related factors in obese elderly (> 65 yrs). So far, results are inconsistent due to methodological issues and study designs. Also, most studies were done in osteoarthritic or coronary patients, and little was done in well-functioning obese elderly; a population at high risk of developing mobility problems that could benefit from primary prevention program. Based on the current scientific literature, additional studies are needed to better understand the impact of the various factors associated with mobility, and to quantify the impact of behavioural approaches and/or preventive interventions in order to maintain or restore mobility and long term independence in elderly individuals. We recently completed a pilot study in obese women aged 55 to 75 yrs to investigate the effects of a 12-week CR program with or without resistance training (RT) (1- CR alone, 2- RT alone, 3- CRT+RT) on mobility. We hypothesized that CR+RT would have greater effects on mobility than both modalities of intervention alone due to the independent effects of FM loss (CR) and improvement in muscle strength (RT). Overall, we found that mobility improved only in the RT group despite no changes in fat mass. No improvements in mobility were observed in the CR or CR+RT even though FM significantly decreased. Based on our results, the next step is to compare the independent and additive effects of CR, RT and aerobic training (AT)