Grant: Operating Grant

Cardiovascular disease (CVD) is the number one cause of death and sickness in Canada, killing 1 in 3 Canadians. The underlying cause behind CVD is atherosclerosis (fatty thickening of artery walls that blocks/slows blood passage). Atherosclerosis is a process that begins silently very early in life, long before the usual risk factors appear (high blood pressure, diabetes). We were shaken to discover atherosclerosis in up to 80% of young men before their 30th birthday, before any of the tell-tale symptoms (chest pain/angina) or risk factors (high blood pressure, etc.) revealed themselves. As it grows, usually by age 50 or more, atherosclerosis in the heart finally does reveal itself and causes heart attacks, or when localized to the brain causes stroke. Prevention of hidden atherosclerosis in all young adults should therefore become a priority to keep it from causing heart attack/stroke decades later. A potentially powerful way to prevent atherosclerosis is with physical activity. Unfortunately, only 15% of Canadians follow the recommendations of 150min/week of moderate activity (brisk walk/jog). Adopting a "some is better than none" approach and to avoid discouraging patients, recently some health advocates have suggested that less physical activity may be enough to prevent CVD. Being cardiologists ourselves, however, we want to give our patients the best advice: if less exercise is as effective in preventing atherosclerosis then we/and our patients should be fine with less. But if less exercise is simply not as effective than more, then we need to know the truth and encourage and motivate our patients to stick with the more stringent recommendations. We will recruit inactive "couch potato" young men and women and assign them to either 1) more exercise, 2) less exercise, or 3) continued inactivity and measure how and why this prevents atherosclerosis to better counsel our patients in the future and hopefully impact policy for a healthier population of adults.