WHAT CAUSES MUSCLE FATIGUE?
We have all felt it at one point or other in our lives. Whether it happened after a particularly intense workout session or towards the end of a competitive game of ball the result was the same; we just felt like we could not go on, and even though our minds wanted to keep going our bodies just could not. Our muscles were fatigued, and once that happens, there is no immediate way around it.
Let us remember briefly what muscles are and how they function before delving deeper into the subject of their dysfunction.
What Is Muscle Fatigue
Muscles are soft tissues found all throughout the body composed of protein fibers that slide past each other, thereby producing a contractile motion that generates movement. Muscles are mainly in charge of maintaining and altering posture, and providing mobility, as well as allowing the movement of internal organs, such as heart and intestines as they push food through the digestive tract.
Muscle fatigue is nothing more than a decline in the performance of muscle fibers. Muscle fatigue naturally occurs when the muscle fibers cannot exert their normal force, and when this happens, a greater effort than normal is required to activate them. There are various factors that can contribute to the development of muscle fatigue such as the accumulation of metabolic byproducts within the muscle fibers themselves to the generation of an insufficient command in the motor cortex. These factors are themselves governed by a number of causes, ranging from sustained physical activity to genetic predispositions that lead to an inherent weakness of the muscle fibers.
Although it is not difficult to identify when our muscles become fatigued, it is quite another story trying to determine the exact mechanisms that lead to fatigue. Muscle fatigue is a serious condition, and it can potentially lead to injury. Because of the dangers, it presents for individuals, especially those that attempt to “push” through it, constant research is being conducted in hopes of learning more about how and why muscles become less efficient over time.
There are two types of fatigue:
- Neural fatigue occurs when the nerves associated with muscle movement are unable to continue generating a sustained electric signal pathway.
- Metabolic Fatigue occurs when the muscle fiber itself loses its ability to contract efficiently.
When muscle fatigue is induced by intense physical activity, it is thought to be caused by the body temporarily depleting its energy supply. The body uses glycogen and ATP molecules as a sort of intracellular engine fuel. When these substances run out our body is not unlike a car running on empty. Eventually, it will stall. Some studies have also suggested that disruptions in the availability of calcium ions within the muscle fibers to be intricately connected to muscle fatigue. Muscle fatigue that is caused by physical activity is generally not treated as a medical problem because the body is able to replenish its stores of metabolic energy after enough rest, which is recommended by many bodybuilders such Jeremy Buendia. If on the other hand, intense physical activity is not the cause muscle fatigue it can potentially be a sign of some serious underlying condition and should be cause for concern.
There is a long-held belief that lactic acid build up leads to muscle fatigue. Lactic acid is synthesized during intense physical exertion and consumed for energy. Any remaining lactic acid after the body has metabolized all the lactate it can handle will slowly start to build up within the muscle tissue itself. Once enough lactic acid accumulates the tissue enters a highly acidic state which causes mild to intense pain in most individuals. Although this reduction in pH levels within the muscle tissue does cause significant discomfort, recent studies into the subject strongly suggest that lactic acid build up is not directly linked to the appearance of muscle fatigue.
Like we mentioned earlier, for most healthy adults, muscle fatigue will correct itself after your body has had enough time to rest; however, let’s look at a few ways in which to shorten the time needed:
Eat to replenish your body’s depleted stores. Consuming lean protein and other nutrient-rich food will go a long way to give your body the required “materials” for rebuilding any damaged tissue. Carbohydrate consumption is extremely important as well. Carbs are used by your body as the primary source of intracellular energy, so consume simple carbs that are easily digested to get the most benefit. While it is never recommended that you work out on a full stomach, it is very important to eat well a couple of hours before your workout and immediately afterward. Finally, staying hydrated goes a long way in staving off muscle fatigue. By drinking enough water, you will be aiding your body to recoup electrolytes. Ten to twelve glasses of water per day is the recommended amount.