Physical exercise: too little or too much?

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ou may be reading this as you’re comfortably lying on your sofa or sitting on your desk chair. Think about the amount of time you spend every day doing this and if you compensate for these doing some sort of exercise. You might be the opposite, maybe the sofa bores you to death and you’re one of those who run one endurance trail on the mountains every weekend and push your body to the limit.

Well, this is not intended as a criticism, only as a wake-up call if you’re concerned about your health. Research data confirm that physical inactivity is a serious global health problem but overtraining can also be a cause for concern (needless to say, only in the first world) especially now that Iron Mans and ultramarathons are in vogue and running a marathon is only small stuff (well, it isn’t and never will be!), it is worth some reflection. If your health is one of your concerns, I’ve got news for you: doing no exercise is a problem but so is doing too much of it.

DOING TOO LITTLE

As I was saying recently here: human beings are designed for movement and when they don’t do it, there are health problems involved. According to the WHO, physical inactivity accounts for one quarter –one quarter!– of risk factors of death rate worldwide. Not only that: again according to the WHO, physical inactivity is the main reason behind 21 and 25% of breast and colon cancers, 27% of diabetes and 30% of coronary heart disease. Now the sofa might not be such a good idea… but, on the other hand, going to the gym is such a chore! Let’s be honest, if paying religiously our monthly gym membership without setting foot in the gym had any health benefit whatsoever, we would all be strong as an oak.

Having said that, one does not have to go to the gym, as physical activity means any kind of body movement made by our muscles demanding energy consumption of some sort: walking, running, going upstairs, doing gardening work, lifting boxes, dancing… any type of exercises within the reach of everyone, at zero costs. Doing exercise and sports are relatively modern inventions: I could swear that 150 years ago nobody in their right mind would do sets of press-ups in the middle of the African savannah. Physical activity was inherent for human beings because our life was at stake. The mere fact of getting food was a physical activity in itself: the Hadza, one of the few untouched tribes of hunters-harvesters in the world, still walk an average of 15 kilometres a day to obtain food and water; we walk less than 50 metres to get to the supermarket… and come back with many more calories than we have used up to get there!

In this context, it is clear that going to the gym helps doing a well-planned and well-organized physical activity aimed to obtain specific results. An adequate level of regular activity for adults contributes to reducing the risk of hypertension, heart disease, strokes, diabetes, breast and colon cancer, depression, improves bone and functional health, and weight control. What do we mean by “adequate”? To put it in simple terms, experts recommend no less than 30 minutes a day of moderate exercise five times a week. This exercise does not have to be uninterrupted: we can do 10 minutes in the morning, 10 in the afternoon, 10 in the evening. This means walking fast, riding a bicycle, doing housework, doing gardening tasks… or going to the gym. Now we know that strength training or exercise is equally or more important than aerobic exercise because when we work our muscles, these muscles release hormones called myokines that, among other benefits, improve osteogenesis –formation of bone tissue–, reduce swelling or protect us from some tumours.

DOING TOO MUCH

The longer we devote to exercise, the more benefits. But there comes a time when overtraining becomes harmful to our health. When? The benefits of physical activity are based on the principle of overcompensation: we train, we push our cardiorespiratory and muscular system and our body, when we are resting, recovers and improves it a little bit, until after some time, this improvement is significant. If we alter the recovery periods, and train again before our body has had time to recover, our body cannot take the challenge and breaks.

Every person is a world in itself, but there are ways of detecting whether we are overtraining apart from doing analysis to measure real data (e.g. levels of catecholamines, cortisol or testosterone at rest). If we overtrain, our defences will decrease and will be much more prone to suffering recurrent infections (especially respiratory), but mainly will suffer an inexplicable poor performance that will not get any better even if we reduce training time or rest, and this situation can take weeks, months, sometimes years. We can even lose weight, sleep poorly, have concentration problems, lose appetite, get injured recurrently or even suffer depression. If you have experienced any of these symptoms, you should revise your relationship with physical exercise and get professional help. But if that’s not your case, go for it!