The Hammer Curl

Vital Variations 1: The Hammer Curl

Louis Degnan, EP


If you were to think about what it means to  “lift weights” or “workout” your first instinct may be to start flexing your arms to show a standard bicep curl. It’s the standard go-to for most who are in pursuit of “guns” or bigger arms. Typically, curls are performed with your palms facing up to optimally recruit the biceps, but it becomes a slightly different exercise when you perform with your hands facing each other. In this blog, we’ll discuss the hammer curl and its unique benefits. 

The hammer curl gets its name from how the exercise looks when you’re holding the weight. This, combined with the motion of the exercise mimics using a hammer to drive in a nail. By flipping your grip so that your palms face each other, the line of pull changes between the weight and your arm muscles. This biomechanical shift requires more recruitment from the brachialis and the brachioradialis muscles whereas the traditional bicep curl isolates the biceps brachii more.  There are several benefits for incorporating hammer curls into your workout:


  • Heavier Weights
    With additional muscle recruitment, one can objectively lift more weight with the hammer grip position than with a traditional supinated (palms-up) position. What is sacrificed in biceps brachii isolation is gained through total weight lifted. Heavier workloads are typically associated with increased muscle size and physical strength. It’s important to perform both variations of this curl to ensure that all of the muscles that make up the “biceps” are trained.
  • Increased Forearm Bone Density
    The heavier resistance placed on the forearm during this exercise may help increase bone density. Studies have shown that heavy resistance training can help stimulate new bone growth. This effect is compounded when heavier weights are lifted over longer periods of time. Not only does the hammer curl put your arms at a biomechanical advantage to lift more weight, it also allows for more load on the forearm joint to help promote increased bone density. 
  • Increased Grip Strength
    Although most upper body exercises require grip strength to perform, the hammer curl is arguably the most sport-specific arm exercise for testing grip strength. Grip Strength is measured using a hand grip dynamometer. Hand and arm positioning for the test is similar to the midway point of a hammer curl repetition. While this benefit might be more neurological than musculoskeletal, the hammer curl is still a great way to work on  grip strength from the ability to lift heavier weights alone.