You go to the gym five times a week so you get enough exercise, right? Not necessarily. Turns out, daily exercise may not negate the adverse effects of sitting for hours on end.

The concept that a sedentary lifestyle could lead to unhealthy outcomes is neither new, nor surprising.

What is new, and disappointing to those who work out regularly, is that daily exercise by itself is not enough to make up for all those hours sitting at a desk.

Indeed, mounting evidence suggests that those who spend hours with little movement are at higher risk of developing cardiovascular disease, blood clots, diabetes and a slew of other conditions fuelled by insufficient physical activity.

Guidelines from the American Heart Association call for 150 minutes of moderate physical activity per week, or about 30 minutes of exercise five times a week. But these guidelines fail to address energy expenditure during the rest of the day.

Assuming the average adult spends 16 hours a day awake, 30 minutes of exercise a day comprises a trivial 3 per cent spent actively. It should come as no surprise that the 97 per cent of time most adults spend in a low-activity state affect their physical wellbeing.

Cardiologists and exercise physiologists use a number called MET to measure how much energy one spends during specific activities.

MET, which stands for metabolic equivalent of task, is the basic unit of energy use. Moderate walking equals three to four METs, while running equals about eight METs. Sedentary activities generally expend no more than 1.5 METs.

The dangers of a sedentary life

Here is the evidence:

1. Absence of muscle contraction during long, uninterrupted stretches of inactivity can unlock a cascade of negative biochemical reactions hindering adequate breakdown of cholesterol and sugar, the chief culprits in coronary disease, strokes and diabetes.

2. People who spend more time sitting have higher levels of triglycerides, as well as lower levels of heart-protective HDL, or “good” cholesterol.

3. Sitting for too long has been shown to increase the amount of calcium and fat build-up inside the heart’s arteries.

4. Sedentary behaviour increased the risk of type 2 diabetes by 14 per cent.

5. A study of more than 50,000 women followed over six years found that each two-hour increase in daily TV viewing led to a 23 per cent jump in obesity.

6. A newly published review of 47 studies reveals that, regardless of exercise, people who spend more time inactive had notably higher risk for cancer.

They were also more likely to die prematurely. And although more physically active people fared better overall, they were not immune to the negative effects of sedentary behaviour.

Get up and walk

1. Count your steps: It can be a great motivator to get up and move. You do not need a fancy tracker device; a simple pedometer will do. Aim for 10,000 steps daily, although more is better.

It is worth mentioning that a recent study questioned that notion, especially when used as the sole target to gauge activity level, not taking into account the speed of walk, the nature of the walking trail, the value of other exercises and the role of diet.

All these additional features have to be factored in.

2. Sit less, move often: Here’s the really good news — you don’t have to replace sitting with vigorous exercise. Research shows that moderate activity, such as a brisk walk or gardening, boosts the value of your health wealth.

3. Don’t give up on exercise: As recommended by the AHA, 30 minutes of exercise five times a week is still vital for your health.

4. The 20-8-2 rule: Some experts recommend that for every 20 minutes of sitting at home or at work, you should stand for eight minutes and move for two minutes.

5. Get bleeped into moving: Set your watch or alarm to remind you to stand up, stretch and take a short walk for a few minutes every hour.

If that is impractical, consider adding a 15-minute power walk to your morning, lunch break and evening.

6. Work while moving: Hold “walking meetings” with a colleague instead of sitting in someone’s office.

7. Find excuses to take more steps: Walk over to a colleague’s desk instead of sending an e-mail, take the stairs instead of the elevator, park in the back of parking lot and walk farther.

• Joe Yammine is a cardiologist at Bermuda Hospitals Board. He trained at the State University of New York, Brown University and Brigham and Women’s Hospital. He holds five American Board certifications. He was in academic practice between 2007 and 2014, when he joined BHB. During his career in the US, he was awarded multiple teaching and patients’ care recognition awards. The information herein is not intended as medical advice nor as a substitute for professional medical opinion. Always seek the advice of your physician. You should never delay seeking medical advice, disregard medical advice or discontinue treatment because of any information in this article.