4. Do Heavy Biceps Curls

Your biceps are the secondary muscle groups to the back (primary muscle group) when performing pullups. Duffy recommends performing mixing in heavy biceps curls every other week or so. Shoot for 4-6 reps, whereas the other weeks, shoot for 8-12 reps.

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5. Do Heavy Pulldowns

"Heavy pulldowns build up your lats, biceps, and forearms, which are the exact muscles and range of motion needed to do a pullup," Duffy says. We recommend working the following: Weeks 1, 2, and 4, perform 3-5 sets of 4-6 reps with heavy weight, for Weeks 3, 5, and 6 perform 3-5 sets of 10-15 reps with lighter weight.

Move to Know: The Pulldown-Row >>>

6. Perform TRX Modified Pullups

Performing several different variations or modifications of the pullup with the TRX, "changes the angle of your pullup," says Duffy. These slight changes in the movement pattern will develop different areas of the muscles in your back, forearms, and biceps to build up more muscular strength and endurance. Work with the TRX on modified pullups once per week for a total of 3-5 sets to muscular failure.

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7. Perform Squat Pullups

The purpose of the squat pullup is to utilize both your legs and your arms to complete a full pullup. "As your arms tire out, you can use more of your legs," Duffy says. "This will slowly help you build more strength in your lats." 

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How to Perform:

Set yourself up in the Smith machine and adjust the bar as needed. Start in a deep squat position and hold onto the bar with your arms fully extended. Use your lats until failure, and as you tire, start using more of your legs in the movement.