True or false? working muscle requires more oxygen. that is why we breathe harder when we exercise.

When we run or perform heavy exercise we run out of oxygen as our heart beats at a very fast rate to produce oxygen.When the body runs out of oxygen,the body produces lactic acid which acts as a substitute for oxygen. Excessive production of lactic acid results in muscle cramps. Hope this helped.

these are common warning signs of overtraining syndrome:

washed-out feeling, tired, drained, lack of energy

mild leg soreness, general aches, and pains

pain in muscles and joints

sudden drop in performance

insomnia

headaches

decreased immunity (increased number of colds, and sore throats)

decrease in training capacity/intensity

moodiness and irritability

depression

loss of enthusiasm for the sport

decreased appetite

increased incidence of injuries.

a compulsive need to exercise

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