Lying triceps extensions, also known as skull crushers and French extensions or French presses, are a strength exercise used in many different forms of strength training. Lying triceps extensions are one of the most stimulating exercises to the entire triceps muscle group in the upper arm. It works the triceps from the elbow all the way to the latissimus dorsi. Due to its full use of the Triceps muscle group, the lying triceps extensions are used by many as part of their training regimen. Triceps extensions are isolation exercises, meaning they use just one joint. While compound exercises are recommended for developing all the muscle groups involved in the functional movement, triceps extensions can be beneficial for fixing imbalances in the triceps or rehabilitating from injury. In bodybuilding, this exercise is used to target the triceps for growth. A study sponsored and done by the American Council on Exercise revealed that the extensions are around 70–90 percent effective compared to the triangle push up for the triceps. However, extensions put no pressure on the wrists so they are an alternative for people with wrist strain or injury. Execution Instructions: Lie on a flat bench with feet on the ground and head hanging just off the top of the bench, so that the edge of the bench rests in the pit between neck and head. Take the barbell with an overhand grip (palms away from body) and hold it out above the head so that the arms are supporting the weight. Do not hold the arms straight over the face at 12 o'clock, but rather at an angle more like 10 o'clock, with feet at 3 o'clock. All of the weight should be on the triceps. Now bend the arms at the elbow, bringing the bar down close to the top of the forehead. Keep the elbows in the same position, do not let them sway outward. Press back up to starting 10 o’clock position. Try to avoid moving your elbows too much; try to keep them the same width apart during the whole movement. Variations Vertical French extension In this variation, the exercise is performed while standing (or sitting on a device with a low backing—that allows the shoulders full range of movement). With respect to gravity, the weight is still lifted in the same manner. With respect to the body, . As with all weight training movements, it is