Although the classic pullup actually targets the back muscles of the latissimus dorsi, or вЂњlats,вЂќ this body-weight exercise engages muscles as diverse as the deltoids, rhomboids, trapezius, pectoralis and biceps as synergists, or muscles that help other muscles perform a movement. The arm-building pullup comes in numerous variations; while there is no single вЂњbestвЂќ pullup for the biceps, some of these varieties target the biceps more than others.
Also known as the close-grip pull-up, this pull-up variation requires you to place your hands closer together than the standard variety of the exercise, which requires you to hold the bar with your hands slightly more than shoulders-width apart. For a narrow-grip pull-up, your hands grip the bar only about 6 to 10 inches apart. This type of grip targets the arms specifically, taking some of the focus away from the upper back.
In this variation, your palms face each other. This grip style can be done using a parallel bar at the gym, or using the parallel grips on certain types on home pullup bars. Like the narrow-grip pullup, the parallel grip helps shift focus from the back to the arms. You can perform narrow-grip pullups with a parallel grip style to target the biceps even further. Neurophysiologist Chad Waterbury, director of the Rickson Grace International Jiu Jitsu Center in Los Angeles, places parallel narrow-grip pullups at number one on his list of the best biceps exercises.
This common pullup variation also goes by the name вЂњchin-up.вЂќ As its name implies, the underhand pullup requires you to grip the bar with an underhand grip - palms facing you - with your hands about shoulders-width apart. At the top of the motion, your chin should clear the pullup bar, as it does in a standard pullup. According to Certified Strength and Conditioning Specialist and BuiltLean program founder Marc Perry, this variety engages the biceps more so than most other types of pullups. Compared to the standard pullup, it also shifts focus from the upper lats to the lower lats.
For any pullup variety, your biceps - and the rest of your upper body - will get a better workout if you focus on slow and controlled motion throughout the exercise. If you've mastered each variety, you can increase the challenge by adding weight to the pullup, either equipping yourself with a weight belt or holding a weight plate between your ankles. Incorporate numerous pullup varieties into your regimen to keep your biceps and other muscles from getting acclimated to a certain variety - vary your grip width, but avoid gripping the bar more than shoulders-width apart. Allow your biceps to recover for at least 24 hours before working them again to promote healthy muscle growth.