This allows you to focus your efforts on just your triceps muscles. Other exercises work the triceps as secondary muscles, such as the chest press or push-up. The tricep extension targets only the triceps without assistance from any other muscle group. The biceps tend to be stronger because it gets more use in everyday life than the triceps. Flexing yourarm to lift and carry loads is more common than extending the arm to lift loads overhead, which works the triceps.