Glucose
The muscles continue to get enough energy during high levels of activity when there is not enough oxygen through the absorption of water. It is a good idea to drink water frequently when doing strenuous exercise.
I think it's because of a process called fermentation
During high intensity exercise, muscles primarily get their energy from stored glycogen in the muscles and glucose in the bloodstream.
Muscles turn chemical energy into heat and work during contraction. Straight from the science book.
When you exercise you use your muscles and your muscles contain Glycogen which could be considered your "energy source". during exercise your muscles use glycogen depleting your energy levels making you feel tired.
After 3 hours of exercise, the main sources of energy utilized by the body are carbohydrates stored in muscles and liver, as well as fats stored in adipose tissue. These energy sources are broken down to provide fuel for the muscles to continue working during prolonged physical activity.
In order to continue living, the body begins to steal nutrients and energy from the muscles.
Fermentation
protein....muscles.
Yes, muscular energy is renewable because our muscles have the ability to recover and regenerate energy through processes like aerobic respiration and stored energy sources like glycogen. With adequate rest, hydration, and nutrition, muscles can replenish their energy stores and continue to function effectively.
Chemical energy stored in the muscles is converted to thermal energy during muscle contraction. This process is not 100% efficient, with some energy being lost as heat.
The macromolecule that stores energy in muscles is glycogen. Glycogen is a polysaccharide that serves as a readily available energy source for muscle cells during physical activity.