The diamond pushup is a challenging close-grip pushup variation. All pushup exercise variations work the triceps muscles to some degree, but the diamond pushup not only works the triceps, it targets the deltoids, traps and pecs.
The diamond pushup has the same basic motion as a regular pushup. The only difference is your hand and upper arm position. For a diamond pushup, bring your hands close together so they set below the middle of your chest. Position your pointer fingers and thumbs so they just touch each other. This hand position forms a diamond shape in the space between your hands, giving this exercise its name. As you lower your body, keep your upper arms tucked in close to your sides.
Your triceps muscles are made up of three heads: the long head, the lateral head and the medial head. The long head originates on your scapula, or shoulder-blade and the other two heads originate on the humerus, your upper arm bone. All three heads attach to your ulna, one of the bones in your forearm. The triceps are mainly responsible for elbow extension, or straightening your arm.
As you press up during a diamond pushup, you extend your arms by straightening your elbows, making the triceps muscles the primary movers. Tucking your elbows into your sides minimizes movement at the shoulder, reducing the amount of work your chest does. However, even though the chest and shoulders are still active during a diamond pushup; they become secondary movers instead of primary movers.
Since your triceps muscles are smaller and weaker than your chest muscles, the diamond pushup is more challenging than a regular pushup. You can do incline or bent-knee diamond pushups to make the exercise easier, but still keep the focus on your triceps. Set your hands on an object that is higher than your feet or place your knees on the floor to reduce the amount of body weight you are lifting and make the exercise easier.