Barbell Bicep Curl (with lower back support)

Begin by standing up straight with an exercise ball between your lower back and a wall. With a barbell on the floor in front of your feet lower down and pick up the barbell holding it in front of the hips with both arms fully extended. Keep your elbows close to your torso and rotate the palms of your hands until they are facing forward. This will be your starting position.
Now, keeping the upper arms stationary, exhale and curl the weights while contracting your biceps. Continue to raise the weights until your biceps are fully contracted and the dumbbells are at shoulder level. Hold the contracted position for a brief pause as you squeeze your biceps. While doing this movement keep pressure into the exercise ball behind you.
Then, inhale and slowly begin to lower the dumbbells back to the starting position. Repeat for the recommended amount of repetitions.