We all know that running makes us healthy. Whether it’s lowering our risk of heart disease or improving our mental health, as regular runners we feel safe in the knowledge we’re doing the best we can to keep fit and well. However, there’s a health risk you might be taking everyday, something you’re unaware of. It can increase your risk of many diseases and running further or faster isn’t going to help. What it is?
Sitting. Yes, the office chair, the sofa, the driver’s seat, all pose a risk. For some, work or small children make a long sit-down a thing of dreams. But for many, working days involve long hours at a desk, and in transport. Sitting has been referred to as the new smoking and it’s important we’re aware of the effect it may be having on our health.
The Chief Medical Officer’s guidelines for physical activity advise a weekly target of 150 minutes of moderate activity (such as fast walking) or 75 minutes of vigorous activity (such as running). What you might not know is that the guidelines also say you need to reduce your sedentary time. Medical research has now shown that the time we spend sitting has its own health risks, particularly type 2 diabetes, which can’t simply be cancelled out by doing half an hour’s exercise. So, that spin class on the way home from work or that Saturday morning parkrun doesn’t mean you can spend the rest of the day sitting at a desk or on the sofa watching TV.
There is good news, however. Once you understand what’s going on in your body, making a few simple changes to your everyday life can reduce the risks of diseases associated with sedentary behaviour.
Most of the major diseases such as cancer, heart disease and type 2 diabetes are in part caused by a low level of inflammation that’s going on in our body. Anything that causes more inflammation will increase our risk. So what causes inflammation inside us and how can we stop it?
The mitochondria are the batteries of our cells. They turn the food we eat into energy for our body to use. Some cells, such as those in the muscles, are packed with mitochondria. They’re constantly churning out energy in anticipation of it being used up. If we don’t use it, then a charge builds up in the cell and the energy is released in the form of free radicals. Free radicals are harmful – they damage the cell’s DNA, which can lead to the cell dying early. Early cell death causes inflammation.
We can avoid this situation by not letting the charge build up. Moving frequently, every 20 minutes or so, will use up the energy, resulting in fewer free radicals forming; those that do are mopped up by anti-oxidants in the cell. The DNA remains undamaged, the cell lives on and there’s no inflammation. Think of that torch in your kitchen drawer that you ignore until there’s a power cut. When you dig it out from under the pile of old phone chargers and cables, you find it doesn’t work because the batteries have leaked and are all crusted up. It’s the same story inside us. Our mitochondria are producing energy for us and we need to use it or damage will result.
One of the other things that causes inflammation in the body is visceral fat. This is the fat around our internal organs and it’s more harmful than the fat just underneath our skin (sub-cutaneous fat). Visceral fat is very responsive to physical activity so, if we’re regularly active and avoid too much sitting, we’re likely to have smaller amounts of harmful visceral fat. You can’t tell how much visceral fat a person has by looking at them. Some slim people have high levels and are metabolically unhealthy. Sitting for long periods of time disrupts the body’s metabolism and the way it uses and stores fats and sugars. The key is to move often. Being active will reduce your visceral fat, limit inflammation and make you healthier, even if it doesn’t result in weight loss.
The other bonus of moving is that, when you move, you use your muscles and they release substances called myokines. Myokines are anti-inflammatories and they zoom around in your circulation even after you’ve stopped moving. That’s a great reason to increase your muscle bulk and add in some strength and conditioning to your fitness routine. Prolonged sitting weakens muscles, particularly the glutes, which is bad news for runners. Weak glutes can result in poor running technique and make you more injury prone.
So now you know how important it is to keep moving frequently throughout the day and avoid sitting for too long.
Always use the stairs, not the lift.