What Is Muscle Fatigue and How Does It Occur? Muscle fatigue is a condition in which muscles cannot exert their normal force. Muscle fatigue occurs when the muscles cannot exert normal force, or when more effort than normal is required to achieve a desired level of force. There are a number of causes for muscle fatigue, ranging from exercise-induced fatigue to genetic conditions which lead to muscle weakness. Doctors and researchers have conducted a number of studies to learn how and why muscles get tired or fail to function normally, as muscle fatigue is recognized as a physical issue which can be very dangerous for patients. (Reference 1)
Where Does the Energy for Muscle Contractions Come From? The source …show more content…
Respiration is a series of reactions in which energy is released from glucose. Aerobic respiration is the form of respiration which uses oxygen. It can be summarised by this equation: (Reference 3)
What Is Anaerobic respiration? Not enough oxygen may reach the muscles during exercise. When this happens, they use anaerobic respiration to obtain energy.
Anaerobic respiration involves the incomplete breakdown of glucose. It releases around 5% of the energy released by aerobic respiration, per molecule of glucose. The waste product is lactic acid rather than carbon dioxide and water: (Reference 4)
What Is Oxygen Debt? Much less energy is released during anaerobic respiration than during aerobic respiration. This is because the breakdown of glucose is incomplete.
Anaerobic respiration produces an oxygen debt. This is the amount of oxygen needed to oxidise lactic acid to carbon dioxide and water. The existence of an oxygen debt explains why we continue to breathe deeply and quickly for a while after exercise. (Reference …show more content…
The air we breathe is a mixture of gasses, predominantly Nitrogen (78%) and Oxygen (20.9%). Although the percentages stay the same at high altitudes, lower atmospheric pressure creates "thin-air."
When your body is exposed to "thin air," it compensates for reduced oxygen levels by increasing the bloods oxygen-carrying capacity, as well as its ability to use that oxygen. Specifically, your body reacts to the thin air at high altitude by:
Increasing natural hormone erythropoietin (EPO) production = increases red blood cell mass for delivering oxygen to muscle cells and converting it into energy.
Boosting total blood volume to move oxygen more efficiently through your bloodstream.
An increase in V02 max (the maximum amount of oxygen the body can convert to work) = giving you more stamina for the long haul.
Elevating capillary volume = creating more blood pathways to muscle cells for improved muscle oxygenation.
Increasing the volume of mitochondria = the powerhouses in cells that help your body turn oxygen into energy.
Increasing the lungs ' ability = to exchange gases efficiently so that every breath you take more oxygen gets into the