I'm planning a Japanese-style action-adventure graphic novel based on characters psychic abilities. One of my characters is going to have the ability to create organic structures within his body. One of the ways I envision him using this ability is to find ways to improve his stamina and endurance.

I had the idea that he could create new cells within his muscles designed to process the toxic products of anaerobic respiration and allow him to respire anaerobically for extended periods of time without tiring.

Is this concept theoretically possible, and would it be the best solution, assuming it were possible to modify one's body?

Thank you for your time!

I think some enzyme that catalyse biochemical reactions to break down lactate may be more plausible than to have specialised cells within muscles.

Lactate is thought to be a possible cause of muscle pain after intense excercise but the build up of which should not really prohibit further anaerobic respiration. On the contrary, pyruvate breakdown into lactate regenerates NAD+ an activated carrier molecule that is consumed in the process of glycosis, and thus should allow for further anaerobic respiration. Though compared to oxidation, this process produces much less energy overall.

So your superhuman character would have impressive recovery after vigorous muscle contractions but I think an improvement in oxygen transport to muscles would be a far better superhuman ability. After all, anaerobic breakdown of pyruvate within muscles occur because oxygen delivery cannot simply catch up with the amount consumed during rapid and intense muscular contractions. In other words, if you can efficiently supply more oxygen to muscles, then that should allow for improved energy generation and muscular performance...

Something that birds have done by developing lungs that allow unidirectional airflow, that prevents the mixing of incoming and outgoing air (that we mammals with our sac-like lungs have to deal with). They also have a more efficient structure supporting their pulmonary capillaries, that improves the efficiency of oxygen exchange and removal of CO2 in the lungs.

If your character could give themself a more efficient lung, perhaps based on a that of a bird, it would probably do the trick.