Train your legs by including unilateral and regular squats for stronger, bigger legs. Research shows that you have to be careful when programming single-limb exercises because if you aren’t, you won’t get the greatest anabolic response. At the same time, unilateral training is critical to correct structural imbalances and provide variation to your program.
Structural imbalances in between the limbs are common in individuals who play a sport where one side of the body is dominant or an implement is held such as tennis, golf, fencing, or speed skating. Imbalances increase the risk of injury and can lead to improper motor patterns, meaning that for optimal performance, health, and longevity, your training program should include structural balancing exercises. Plus, unilateral lower body training in addition to regular bilateral training has been shown to result in faster short sprint times, even in elite sprinters. It makes sense that training each leg individually will make you faster and more powerful since running and jumping requires you to produce force off of a single leg.
A new study in the Journal of Strength and Conditioning Research tested the difference in muscle activity and testosterone response to unilateral and regular back squats. Participants were male college football players and track athletes. They performed four sets of ten reps of back squats and unilateral dumbbell “pitcher” squats with a 10-RM load on two different days (one type of squat a day). The “pitcher” squat is sometimes called the “rear-foot elevated” squat and is done with one foot elevated on a bench behind the athlete. Muscle activity of the lower back and legs was measured with electromyography and testosterone levels were tested.
Results showed that the two types of squats produced statistically equal testosterone response to training. Researchers were surprised that the unilateral squats actually triggered a slightly greater testosterone response at all time points of the study than the bilateral back squats. This was particularly unexpected because the total volume of work was more than double for the back squats over the unilateral squats. Both exercises produced comparable muscle activity in the lower body, although the quad was slightly more activated in the back squat exercise than the unilateral squat exercise, but not to a statistically relevant degree.
Researchers explain the similar neuromuscular activity and hormonal responses between the two squats by noting that in the unilateral squat, weight distribution is biased to one side of the body, placing additional stabilization demands upon the neuromuscular system. They suggest the unilateral squats triggered an anabolic response of testosterone that was equal to the back squats because, although they only used one side of the body, the “pitcher” squats were a multi-joint exercise that used the largest muscle groups in the body at a heavy weight. Previous studies that tested the effect of unilateral training onhormone response have not demonstrated a very large anabolic response—elevations in both testosterone and growth hormone have tended to be small from unilateral training.
For best strength and anabolic results, unilateral lifts can be used, but ensure that when you train unilateral lifts that you start with large muscle mass exercises to trigger testosterone—lower body exercises such as squats, power cleans, and deadlifts are recommended at a high percentage of the 1 RM, with a high total volume. Based on this study, heavy unilateral squats can be trained on certain days in place of the regular back squat, but it’s never ideal to exclusively perform one style of lift. Train strategically and you’ll get faster, stronger, and bigger.
Jones, M., Ambegoankar, J., et al. Effects of Unilateral and Bilateral Lower-Body Heavy ResistanceExercise on Muscle Activity and Testosterone Response. Journal of Strength and Conditioning Research. 2012. Published Ahead of Print.