- All subjects will be sedentary. Sedentary will be defined as those with an occupational calorie expenditure that is not estimated at greater than 50% above basal (desk job or light activity at work: on feet 30-50% of the work day) and whose exercise activity is defined as sedentary according to a self-reported activity questionnaire, and confirmed by actigraphy measurements. Sedentary lifestyle will be defined as fewer than four 20 min episodes of moderate or vigorous intensity activity in the previous four weeks.