What is the amount of energy released when nutrients are burned

How can a person  best  reduce the risk of injuries on the road?  

Can occur if you do not modify your workout after a break

The amount of oxygen that is actually used by the body during the rest or a hand workout is determined by the heart rate, the stroke volume, and the amount of a. blood circulating in the vascular system b. oxygen removed from the vascular system c. oxygen provided to the vascular system d. blood that individual has in the body e. hemoglobin in the red blood cells