Prolonged time spent sitting and being sedentary is associated with an increased risk for heart disease, cancer and death, regardless of physical activity, according to a new study.

The meta-analysis review, published Monday in the Annals of Internal Medicine, examined 47 different studies that looked at sedentary behaviour and a range of negative health outcomes.

The review found that prolonged periods spent sitting was associated with a greater risk for all-cause mortality, heart disease incidence and death, cancer incidence and death, and Type 2 diabetes in adults.

This association was more pronounced among people who do little or no exercise, the study found.

"The findings suggest that the health risk of sitting too much is less pronounced when physical activity is increased,” PhD candidate and lead author Avi Biswas said in a statement.

Study co-author Dr. David Atler, from Toronto's University Health Network, said the study should serve as a "call to action" to the scientific community, and that more research needs to be done looking into the different ways sitting is detrimental to our health.

He also warned that despite the health benefits that come with physical activity, exercising by itself may not be enough to offset the risk from sitting.

"Our study finds that despite the health-enhancing benefits of physical activity, this alone may not be enough to reduce the risk for disease," he said in a statement. "It is not good enough to exercise for 30 minutes a day and be sedentary for 23 and a half hours."

He told CTV News that public health initiatives should not just promote physical activity, they should also promote "getting off our rears" to minimize sitting time.

"Decreasing sitting is not a replacement for exercise, and exercise is not a replacement for sitting more. They are both important to do,and do more of," he said.

Atler says people should aim to decrease the amount of time they are sedentary by two to three hours over the course of a 12-hour day.

He suggests the following strategies to help reduce the amount of time spent sitting:

  • Track time spent being sedentary so you can work to reduce the overall amount;
  • Set achievable goals and find opportunities to incorporate physical activity in your daily life;
  • Set an alarm to remind yourself to stand up at work and move around for one to three minutes every half hour;
  • Consider a standing work station;
  • While watching TV, stand up and exercise during the commercial breaks.

He noted that it is important for employers to recognize the impact of prolonged sitting on their employees, and encourage workers to get up and move throughout the day.

"The bottom line here is awareness," he said. "Let's get this out in the field and begin to talk about it and address it."

The study concludes there needs to be more public awareness about the hazards associated with sedentary behaviour.

The new study builds on a body of research examining the negative health effects associated with sitting.

A meta-analysis published last summer found that watching TV and other sedentary activities were associated with an increased risk for colon, endometrial and lung cancer.

With files from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip