Daytime Naps Once or Twice a Week Can Be Good for Your Heart, Study Finds A new study says just one or two naps per week can reduce the chances of a heart attack. The five-year analysis can be found in the medical journal, Heart. Nearly 3,500 subjects were tracked by a team from Switzerland's University Hospital of Lausanne. All of those involved in the study ranged from 35 to 75 years old. To get results, researchers observed the relation between cardiovascular disease development and napping regularity. They found that those who napped up to an hour had a near 50 percent less chance of developing health issues. Researchers add that a nap could be as short as five minutes. They also say that the number of naps taken per week was irrelevant in terms of a connection to heart health.