Tricep extensions - These are done while lying flat on your back with your knees bent and feet slightly apart on the floor. Hold the weights with your palms facing each other. The weights should be held straight up above your chest about as far apart as your shoulders. Slowly bend your elbows and lower the weights until the elbows are bent at 90 degrees. The upper arm should remain in the upright position as you lower your lower arms bringing the weights down toward the floor. At the end of the extension, the lower arm should be perpendicular to the floor. Hold the position for ten seconds, then slowly straighten your arms at the elbow until you are, once again, in the straight arm (extended) position. Repeat this for at least 10 times. Rest for one minute, and repeat at least one more time. To increase the tension on the muscle, you can increase the weight or develop the exercise until your lower arm allows the weight to touch the floor near your ears. Note: you don't need to invest in handweights or dumbbells to do extensions. Books are easy to hold on to and you can vary the weight by choosing thicker books. As your strength and endurance improve, you may want to consider a dumbbell set so that you can gradually increase the weight. In lieu of increasing the weight, you can perform more repetitions.