Try the Ironman Position of Flexion 4x Downward Progression Pyramid Workout for Big Biceps

Midrange: Seated DB curls, 4 x 12, 10, 8, 6
Stretch: Incline curls, 3 x 12, 9, 7
Contracted: Concentration curls, 3 x 12, 9, 7
Finisher: Undergrip pulldowns (X-centric), 1 x 7

Increase the weight slightly on each set. Rest 45 seconds between sets.

An X-centric set is raising the weight in one second and lowering in six on every rep.

Source:
X-Reps

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