Haskell, James. 10 Reasons Why Women Should Always Lift Weights. January 19, 2017. Retrieved from
No matter your fitness level, every time you lift weights during your workout your muscles do become fatigued. It is part of working out and we all experience it. But the answer to this is not as straight forward as one may think.
Muscles become fatigued because of the process that they got through every time they are engaged repeatedly. According to Christian Moro (TED Ed on shockmansion.com) this process while complex, happens in a fraction of a second. Moro continues to describe the process by saying that the motor neurons are “the signals that travel from the brain…motor neuron and muscles are separated by a tiny gap.” (Moro TED Ed on shockmansion.com). Within this gap, there are two sides that the particles go across this gap that enables the contraction of muscles. One side contains the “motor transmitter called acetylcholine and then the other side has ions that line the cell’s membrane-potassium on the inside and sodium on the outside”(Moro TED Ed on shockmansion.com). This process is how our muscles contract all happening so quickly that we don’t give it much of a thought.
What we do give thought to is when our muscles get sore and it becomes harder to continue lifting. With the use of a molecule called ATP, it pumps the ions across the membrane, which resets the balance of potassium and sodium on either side (Moro on TED Ed on shockmansion.com). The longer someone works out and makes the muscles contract repeatedly, the more difficult the process becomes to repeat and is why we feel the need to stop or like we can’t lift the same weight anymore, at least for a small amount of time. When it becomes more difficult that means that there are not enough ions available for the cell membrane to continue the process with such ease. Taking a break for a few minutes to allow the potassium, sodium, and calcium to be sent up to the muscle in the arm from other parts of the body will allow you continue your workout again (Moro TED Ed on shockmansion.com).
As someone who is not an exercise junky but does appreciate those who do, this video did help me understand why my arms and legs truly get sore during my workouts. There are plenty of rumors but this video does make sense as to why people tire at different rates. The more you exercise, the stronger you become and the process does take longer for an area to tire while someone who does not do this as much tires sooner and more often. Watching this video was like getting a mini science lesson and made me rethink the idea of taking breaks during a routine. Until you have built up a stamina for this, it is hard in the beginning. But keep at it everyone and it will get easier!
To learn more about the entire process, watch the video here: