Back dimples, or Venus dimples, are desirable indentations on either side of the spine just above the butt. Back dimples are caused by a visible cleft in the sacroiliac joint and are widely believed to be genetic. However, a high percentage of lean athletes sport Venus dimples. While spot reduction is not possible, a combination of cardiovascular conditioning and lower back exercises may help you achieve back dimples.
According to Scientific American, the average body fat percentage for men and women in the United States is 22 percent and 32 percent, respectively. When muscles are covered by a layer of fat, a toned appearance is impossible. Because elite athletes aim for body fat percentages in the range of 6 percent for men and 12 percent for women, the kind of definition that creates back dimples is more possible. Cardiovascular conditioning coupled with a healthy diet is the best way to achieve a lower body fat percentage and achieve visible Venus dimples. Rowing machines provide both aerobic and anaerobic conditioning, and strengthen the lower back muscles more than other cardiovascular exercises.
Back extensions target various muscles, including the spinal erectors. They are connected to weight blocks that can be adjusted according to your strength. Sit on the machine with your butt against the back of the seat and adjust the padded rollers so they rest against your shoulders. From an upright position, push against the rollers using your lower back muscles until your body is almost horizontal. Slowly return to an upright position and repeat.
A Smith machine is a barbell attached to two vertical guide rails that limit the range of motion. Smith machines allow individuals to perform barbell exercises safely and without spotters, as the bar cannot be dropped if the user loses her grip or cannot complete the lift. Both deadlifts and overhead squats can be performed on a Smith machine to increase lower back definition. Scott Carrell, ISMA Certified Personal Trainer, states that the deadlift is one of the most effective exercises for targeting the muscles in the lower back. The overhead squat is another back-focused exercise that can help you achieve Venus dimples. Unlike a regular squat, overhead squats require the user to hold the barbell above her head while performing the movement, activating the back and core muscles to maintain balance, control and stability.
A popular core machine, the Roman chair can also target the lower back muscles. The Roman chair offers a movement similar to the back extension without additional weight. Position the front of your thighs on the large pad and secure your feet and lower legs under the second padded bar. Bend at the waist until your body is at a right angle with your head closest to the ground. Using your lower back muscles, lift your torso until it is parallel with your legs. Keep your hands behind your head throughout the movement to help isolate your lower back muscles.