Sport: these four received ideas that harm our health

Jean-Marc Delorme, with Europe 1 6:59 p.m., August 26, 2021

DECRYPTION

Like bad habits, bad sports ideas are tough.

We always hear everything and its opposite when it comes to physical activity.

Sweating which would make you lose weight, running which would be bad for the back or even stretching which would prevent the appearance of aches… So many received ideas that harm the sports practices of the French, lost in a flood of contradictory injunctions.

But it is not too late to start the return to school in top form and well informed, thanks to columnist Jean-Marc Delorme who sets the record straight on the program

on Europe 1.

Sweating makes you lose weight

"People who still think that are wrong. It's simple: when you sweat, you lose water that you will take back immediately after you are hydrated post-exercise. Because sweating actually comes from thermoregulation, c that is to say that the body changes its temperature according to the intensity of the exertion. The human body is made up of 60% water and it is absolutely aberrant to see people who play sports with sweat suits, which are made of a non-breathable material. It only has a few benefits but if you continue you can get dehydration and start losing amino acids. It's dangerous for muscle function. And then, when our body lacks water, we have cramps,breakdown… 1% dehydration is equivalent to 10% loss of physical capacity. As you can see, you have to drink as soon as you sweat. "

Running is bad for the back 

"It's an excuse not to go for a run because running is really a great activity for building back muscles. According to an Australian study from Belavy Deakin University from 2017, a run at 9 km / h would allow rehydrate the intervertebral discs a little bit, making them thicker. It also strengthens all the muscles surrounding the spine. However, you must run in good conditions, that is to say with good shoes and in having an adapted running technique. "

You have to do sit-ups to lose belly fat

"The 'BBQ' effect doesn't work! The abdominals are made up of the transverse, straight, small obliques and large obliques. Doing sit-ups as we know them, in the traditional way, on the lifts of the trunk, is a concentric effort. , in other words the abdominal muscles will grow bigger without removing the fat already present. You will therefore get the chocolate bars as well as the mousse, which will remain! And for sure you will appear more voluminous on the belly, which is not not really the desired effect… To eliminate this abdominal fat, you will have to manage your diet, do expensive calorie exercises, and you can accompany this with a sheathing exercise which will solicit the fibers of the transverse muscle and reduce your periphery abdominal. "

Stretching is necessary to have less muscle soreness

“Stretching will allow the muscle fibers to be returned to their initial length. When we have aches, they come from a contraction that we call eccentric, called braking, and this contraction breaks the fibers. cannot repair broken fibers. On the other hand, 30 to 45 seconds of stretching per muscle group will eliminate the stiffness. It is often even advisable to wait 48 hours before practicing the stretching in case of great eccentric efforts. In case of muscle aches, which will usually appear 48 hours after exercise, be patient, your body will take care of the rest. "