Guys with a lot of muscle and a heavy back squat are instantly cut down to size when performing side lying adductions as the entire movement is dominated by the inner thighs and obliques. Attempting to get one leg to touch the other while maintaining a straight bottom leg is the goal here. Using a mat on top of the box will help the working leg feel comfortable. Sets of 10 reps per side should be more than enough. – Lee Boyce
