Fitness Tools A B aerobic anything that makes your heart go fast hamstring The muscle in the back of your leg, above your knee heart The muscle that pumps blood target heart rate 140-180 beats per minute pulse your heart beat quadriceps the muscle in front of your legs, above your knees triceps push ups make them stronger abdominals crunches make them stronger sweat it cools your body down when you exercise stretch it makes your muscles longer chest neck wrist three places to take your pulse sweat trophy a drop of sweat running down your face