Dominick Alejandro Garcia Lopez

Hello everyone and welcome to Move With Me, the mini podcast where we explore how our body works. I'm Dominick Alejandro Garcia Lopez, and today we'll talk about muscles and how they work when we lift something heavy, like some weights. The muscular system is the set of all the muscles of our body. We have more than 600 muscles! Muscles are like ropes or elastic bands that can be tightened and relaxed. The main function of muscles is to contract to generate movement. Thanks to them we can raise our arms, walk, run or throw a ball. In addition, they help us maintain posture and stand up. Let's imagine that we are going to lift a weight, for example a dumbbell from the floor to chest height. First, the brain sends a signal through the nerves to the muscles. When you receive the order, the fibers of the muscles contract; that is, they shorten and tighten, as when you stretch a garter. To lift the weight with the arm, the main muscle that works is the biceps (that of the front of the arm). When contracting, the biceps shortens and pulls from the forearm bone, causing the elbow to bend and the weight to rise towards the chest. At the same time, another muscle in the back of the arm, the triceps, relaxes so as not to interfere. This action where the muscle shortens while lifting the load is called concentric contraction. When you have already lifted the weight to the chest, you could hold it like this for a moment before lowering it. At that moment, your muscles maintain the contraction without moving the weight more; it would be a brief isometric contraction. Then, when the weight slowly lowers, the same muscles (such as the biceps) continue to work, but now they lengthen in a controlled way so that the weight does not fall suddenly. This movement of descending carefully is an eccentric contraction. It is important to mention that the muscles always work with the bones as support: imagine them anchored to the bones as hooks or levers. When a muscle contracts, it drails the bones and thus we achieve the movement. In other words, bones are the firm structure, and muscles are the engines that pull that structure to move us. Funny fact! Did you know that our body has more than 600 muscles and that each muscle fiber is thinner than a human hair? Despite being so thin, each fiber can support a thousand times its own weight. This shows how strong our muscular system is. Well, friends, that's all for today. Remember that lifting weight is just a way to understand how our muscles work every day. So the next time you lift something heavy, think about how your biceps and other muscles contract and make that happen. Thank you very much for listening to Move With Me. I hope you enjoyed this episode and feel inspired to keep moving. Until next time, stay active and energetic!