Answer:
Gets the blood pumping
Step-by-step explanation:
Honestly im not sure which muscles or muscle group you were reffering to, but when doing warm ups whether that be push ups, jumping jacks, squats etc.. they all increase your heart rate and make the blood in your body pump faster, especially the muscle your specifically working at the moment. Muscle strains, torn muscles, sprains, and broken bones can be prevented by warming up the body first.