How do muscles continue to get energy during high levels of activity when there is not enough oxygen?

Your muscles use Anaerobic Respiration or more commonly fermentation of Glucose.

Glucose ---> Lactic Acid + Energy (ATP)

C6H12O6 ---> 2C3H6O3 + 2 ATP

The energy released is about 120kJ per mole Glucose.


Lactic Acid is produced as a byproduct as well as Energy. Should levels of activity continue past your glucose reserves the body will start to feed off of itself and consume muscle . This can be reduced by replacing glucose stores during workouts, i.e. sports drinks that are high in glucose and electrolytes.

anaerobic respiration

pussy

They do only the first phase of sugar breakdown - glycolysis because the Krebs cycle is much more oxygen intensive. You take sugar and turn it into lactic acid in the muscle. The lactic acid is picked up and moved elsewhere to finish the breakdown of it.

This happens through fermentation.

Breif explanation:

The glycolysis cycle takes place in the cells and ends up with producing two pyruvic acid, then if oxyegen exists , those pyruvic acids is utilized in krebs cycle (citric acid cycle), while if oxygen is absent, it goes for fermentation..

The study of fermentation and its applications is called zymurgy

So, there are two ways for the muscle cells to obtain energy.

First, they still undergo aerobic respiration to release energy.
glucose + O2 ----> CO2 + H2O + 36 ATP

Thus, when extra energy is in need, the cells can undergo anaerobic respiration to release extra energy.
glucose ----> 2C3H6O3 + 2 ATP

by anaerobic glycosis - 2 molecules of ATP is produced. the end product is lactic acid.

This is the Kreb's cycle. The muscle goes into oxygen debt and the by product now is Lactic acid. This is the "pain" you feel.

Well, I was going to say that muscles can't function without oxygen, but looks like your panel of "experts" has something far more logical than anything I could ever imagine.

Glucose reacts with something else. whatever it is. This gives out energy and latric acid meaning pain.

by undergoing anaerobic respiration. by product is lactic acid, and is responsible for the "burn" that we feel in aching muscles.

lactic acid, which is why your muscles start to burn...drink gatorade to up your electrolytes after an intense workout, and if you're going to be doing high-energy, aerobic exercise for more than 90 minutes, make sure you stop for a quick carbo and protein snack, like a powerbar or half a PB sanwhich on whole wheat bread.