Independence – of thought, of movement, and of choice – often proves to be a deciding factor in whether you’re on the road to building the physique of your dreams or not. In the gym, one form of independence can come via unilateral training, which is the practice of training one side of your body independently from the other.
When we train, we often fail to consider that virtually any muscle group in the body can be isolated. We squat, we bench and we deadlift with both hands on the bar and both feet on the floor, but it’s possible — necessary, even — to effectively work one side without involving the other.
If you can perform a movement with two hands gripping a barbell, chances are you can do the same movement with one arm or leg. This ability to isolate is a critical element to muscle growth and strength.
WHO GO UNILATERAL
Unilateral training can lead to greater muscle growth. Research shows that when you work one arm, it is significantly stronger than it is during bilateral exercises. Scientists theorize that you are stronger unilaterally, because you use more fast-twitch muscle fibers in each muscle of the limb being trained than you do when using both limbs together. Being able to lift more weight with one side means that you place more overload on that muscle, which can result in greater gains in strength and growth over the long run. Plus, greater muscle activity means using more fibers within your muscles. More of those fibers are going to grow bigger, which will add up to greater mass gains.
>> A study from Iowa State (Ames) compared strength during unilateral and bilateral exercises. They had males do a biceps curl exercise with 1) the left arm only, 2) the right arm only, and 3) both arms at the same time. They measured the amount of force (strength) produced during each trial and measured the amount of muscle fiber activity with electromyography. To determine the strength deficit with bilateral training, they added the force measures from the left-arm-only and right-arm-only trials and compared the sums to the amount of force applied during the bilateral trials. Not only did the unilateral training allow more force to be applied by each arm (about 20% stronger; i.e., each arm was 10% stronger during unilateral training), but the activity of the muscle fibers in each arm was greater when trained unilaterally.
Unilateral training will make you stronger. Training one side of your body at a time significantly strengthens your core. And building a stronger core makes you stronger on almost every exercise.
>> Scientists from the Memorial University of Newfoundland (St. John’s) wanted to confirm which exercises were best for strengthening the core muscles. They tested the activity of three major core muscle groups — upper-lumbar muscles, erector spinae muscles and lower-abdominal muscles (including the deep transverse abdominis and internal obliques) — during several core exercises (bridge, pelvic tilt, alternate arm and leg extension, parallel hold, side bridge and superman on an exercise ball and on a stable platform, as well as during unilateral and bilateral dumbbell chest presses and shoulder presses. The unilateral shoulder press significantly activated the upper-lumbar and erector spinae core muscles, and the unilateral chest press significantly activated all three core muscle groups, compared to the bilateral versions of those exercises.
HOW TO ADD UNILATERAL TRAINING TO YOUR PROGRAM
Determine weak points. Do you have a lagging muscle group that’s negatively affecting your symmetry? Do you have form issues with compound lifts, such as the bench press and squat? Examine these things and be honest with yourself — or ask someone else to take a look at what you’re doing and give you their opinion.
Perform unilateral exercises first during training sessions. Since you are stronger at the beginning of a workout, do unilateral exercises first to maximize the amount of weight you can use.
Don’t let the weight being lifted become more important than range of motion. In order for unilateral lifts to be as effective as possible, allow your body to exploit the additional freedom of movement these exercises provide.
Unilateral training strengthens both sides of the body. Although your other side only comes into play in a supportive role — either for balance or to provide structural support to the muscle group being worked — research shows the nontraining side also gains strength. This is known as the contralateral effect.
>> A study from Australia that analyzed 16 investigations of contralateral training reported that the gains in strength of the nonworking side are on the average of over 10%. These results are due to the changes that the nervous system undergoes. How does this help you when you train each side unilaterally? If your resting side is getting a small benefit while the opposite side is working, then doing one set of unilateral exercises for each side is like doing one and a half sets for each side. With two or three sets per side, the resting side gains a contralateral benefit.
Unilateral training helps strengthen the mind-muscle connection, which can lead to even greater muscle growth. Rather than just lifting a weight for a prescribed number of reps, experienced bodybuilders stress the importance of achieving a strong mind-muscle connection to get the most benefit from their training and, thus, make greater gains.
THE ONE-SIDED WORKOUT
We’re sure you’ve heard of the one-sided workout split — training the left side of your body on one day and the right side the next. Hey, if you’ve been training long enough, you’ll try anything to keep it interesting, right? Yet, unilateral training is not an ideal way to work out on a routine basis, mainly because research has shown that anabolic hormones, growth hormone and testosterone are not boosted as high in unilateral training as they are in bilateral training. So, we recommend trying this method as a change of pace to keep your muscles guessing and growing.
Because you are only training half of your muscle mass with a one-sided training split, you do not release as much GH and testosterone as you normally would when you train both sides of your body. That’s because one of the critical elements of hormone release during weight training is the amount of muscle mass being trained. The more muscle mass you work, the higher the hormone response. With one-sided training, you are only working half the muscle mass you normally would, so fewer hormones are released.
ONE-SIDED SPLIT
MONDAY: Upper body, right side
TUESDAY: Upper body, left side
WEDNESDAY: Rest
THURSDAY: Lower body, right side
FRIDAY: Lower body, left side
SATURDAY: Rest
SUNDAY: Rest
INJURY PREVENTION AND REHABILITATION
Training one side of your body will improve your balance — not your symmetry, but your sense of balance. For example, when you perform single-leg squats, you’re forced to maintain your balance in order to complete a rep. Improving your physical balance will help you avoid injuries.
When you have an injury, sometimes unilateral training is the only way you’ll be able to get anything done, since you’ll either need to work around a bodypart or you’ll need to find a way to move without pain in order to avoid stalling your progress
