Dr Timothy Byers, co-chair of the American Cancer Society’s Cancer Prevention Committee and professor of preventive medicine at the University of Colorado says that of all the behaviours that are health related, exercise is by far the most important: "It is strongly protective for heart disease, diabetes and some forms of cancer…and is essential for a lifetime of weight control."

Byers said in a recent article in USA Today, that if there were one guideline he wishes people would take seriously, it is the original federal guideline to do at least 30 minutes of moderate activity most days of the week: "It can be done in 10 to 15-minute increments. Any activity is better than none, and more is better than a little, he says.