Multiple Risk Factor Intervention Trial in Breast Cancer Survivors

This study aims to produce new evidence on the efficacy of exercise and diet for cardiometabolic risk reduction in BC survivors. Using a 3-arm RCT with to 6 months of 1) exercise following Health Canada guidelines; 2) the same exercise plus counselling to follow Canada's Dietary Guidelines to improve diet quality; or 3) stretching group, this study will answer the following questions:

* What is the impact of exercise on cardiometabolic health and body composition in BC survivors? * What is the effect modification of adding a diet quality intervention to exercise on cardiometabolic health and body composition? * Is there a link between the capacity of skeletal muscle adaptation to exercise (and diet) and insulin resistance in BC survivors?

The investigators hypothesize that: 1) exercise will improve cardiometabolic and body composition outcomes 2) improvements in cardiometabolic outcomes will be enhanced by the addition of diet quality, which will be essential or additive for Matsuda index, metabolic syndrome, Framingham CVD risk, thigh myosteatosis, muscle mass, VO2peak, 3) skeletal muscle insulin signalling transduction will be impaired in BC survivors via dampened expression of insulin-responsive proteins (e.g. GLUT4) and co-occur with impaired muscle quality (e.g., higher rates of fat depots, presence of fibrous tissue) negatively impacting insulin signalling.