They produce less waste, they provide better contrast, and they are faster.
The correct answer to your question is dyspnea
let me know if you have any other questions
:)
The best way is to eat enough of protein every day. Different recommendations can be found but a very good ballpark is that you eat around 0.6-0.8g or protein per pound of your own weight.
Another and more important thing is to add a weight training regimen into your life which will help and slow down muscle loss.
Answer:
to get the energy they need for short bursts of intense activity.