Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Adjust the height of the seat on the preacher bench so that when you sit on it, the back of your upper arms sit comfortably flat on the padding. Grab a dumbbell with your left hand and sit on the preacher bench. The back of your left arm should rest flat on the padding with your arm fully extended. Place your right forearm on the padding for support. Execute the exercise by slowly raising the dumbbell and squeezing the bicep at the top of the movement. Slowly lower the dumbbell until your arm is fully extended. Repeat for desired reps, and then repeat the same for the right arm.
As a general rule, always hit the weakest arm first. In most cases, this is the left arm. Keep the rep timing slow, and control the weight on the way down. Focus on only moving your forearm.
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