Running is a sport practiced by many. Convenient because it can be practiced anywhere, in any climatic condition, in company or alone, outdoors or indoors, it is an economical sport. A mix of excellence to make it a fascinating and attractive sport. It is a simple sport that allows you to maintain and develop good physical shape by improving cardiac and circulatory efficiency. But it is also a pleasant activity. In fact, it seems that it has a relaxing activity and improves mood. It is now amply demonstrated that running regularly is good for your health, it lowers the amount of sugar in the blood, it helps circulation, it helps you lose weight and stimulates a good mood. You can run to get moving, you can run to lose weight, or you can run to compete. Against other runners, sure, but also against your own limits. Trying to overcome human abilities is perhaps the most hidden thought of many agonists. Go further and further, to infinity, without ever setting limits. And this is where science comes in: to mark the arrival! Man could run up to 65 km/h, significantly exceeding the 45 achieved by Usain Bolt for his 100m world record. This was stated by research published in the Journal of Applied Phisiology, according to which the limiting factor is not power muscle, but the contact time between the foot and the ground during running, a factor that improves with training but also with the increase in height of the runners.