Muscles worked: This exercise emphasizes and develops the biceps muscles, which are located on the front of your upper arms and are primarily responsible for bending your elbows, as well as the brachialis and brachioradialis.
• Sit on the bench with one leg on either side of it.
• Reach down and pick up the PowerBlocks (or Dumbbells) and bring them to your side your palms facing forward.
• Sit upright or lean forward slightly with your upper arms by your sides (although not "smashed" against them). Lift your chest, tighten your abdominals and maintain a very slight arch in your lower back.
• Curl the PowerBlocks (or Dumbbells) forward, then upward, and then in toward shoulders while keeping your elbows at your sides and your upper arms completely still.
• Slowly lower to the starting position by performing the same arcing motion.
• Keep elbows at your sides.
• Keep wrists straight.
• Keep your trunk muscles tight and maintain a very slight arch in your lower back.