I own a gym and I train and compete in triathlon, so you would think I move around a lot, but the truth is I own a business – which means I sit a lot – more than I would like. There are days that, after my morning workout, I sit for 12 to 16 hours and I am here to tell you it hurts.

It’s kind of like a big eraser removing the benefit of the training I just did. Muscles don’t recover properly, blood doesn’t flow well, nerves are numbed, circulation reduced – it’s a problem.

Several studies have been done on people who sit a lot and those who don’t.

The results are alarming. And what gets me is an hour a day of exercise cannot erase the damage of four-plus hours of sitting.

This morning I ran for just over two hours but since then, I have been sitting at my desk for 10 hours. One study showed that people who sat at a desk or on a couch watching TV for more than four hours a day had an increase in death from any cause of over 50%.

In a study done by Dr. James Levine, a group of test subjects were all given 1,000 calories per day more than they needed. Some of the subjects didn’t gain a thing, while others gained weight quickly and to excess. Clearly the food itself wasn’t the issue, so Dr. Levine went about exploring further.

Those that sat less than two hours a day, who moved around more, who fidgeted and unconsciously moved all day long, burned up the extra calories, while those that sat more than four hours per day stored them as fat.

So why is this happening? Our legs are the biggest muscles in our body.

When we sit – we turn them off because they are not required. When your biggest muscles stop burning energy, stop flowing blood, stop creating circulation of fluids and turn off, your body will store fat, slow down and cause all manner of problems.

The studies showed increases in DVT (Deep Vein Thrombosis), cancer, diabetes, insulin resistance and fat stored around the midsection.

Another study, published in the online medical journal BMJ Open in July

2012, found that we could gain an estimated two years of life expectancy by reducing sitting to less than three hours a day, and gain 1.38 years from reducing television watching to less than two hours a day.

So what can we do about it? At work I sit on a rubber ball chair called the Evo Chair. It’s like an exercise ball, on a frame that has wheels on it so I can move around. It isn’t perfect, but at least it creates movement in my legs. I try to make sure I get up for frequent breaks and plan my day to have training clients spaced out to keep my sitting to a minimum when I can.

What else can you do? There is a growing trend towards treadmill desks, so that you can walk while you work. Apparently this takes some getting used to but I can also see how it would really keep your legs active and bring you back towards our ancestral heritage of always moving.

You don’t need to get fancy either; a cheap treadmill with some basic supports will work. You can also raise the height of your desk and stand instead of sit – of course standing all day can cause varicose vein issues, so that’s not a great solution.

At the end of the day, if you are one of those people who exercises faithfully for an hour a day, but still cannot get rid of that belly fat and you sit for more than four hours a day, this could be the secret change that not only saves your life, but gets you lean.