 The objective of this study is to provide insight into the effects combined training frequency has on improving fitness, ease of physical activity, and maintenance of a high total energy expenditure. Such information is critical to our understanding of ways to improve well-being, quality of life, and independence of an aging population. 105 participants will be enrolled in this study. The length of time for your involvement in the study will be 32 weeks. You will undergo the procedures listed in this consent form on 3 separate occasions-initially at your entry, at 16 weeks and again at 32 weeks. 