Human movement is reciprocal in nature: Opposing muscle groups must coordinate for proper movement.
Muscle length and strength between opposing muscle groups need to be in balance for normal movement and function.
There are two primary types of muscle imbalances:
- Body muscular imbalance. The muscles on each side of your body should be symmetrical with each other in size and strength. When a muscle (or muscles) on one side of your body is larger, smaller, stronger, or weaker than the corresponding muscle(s) on the other side, you have a muscle imbalance.
- Joint muscular imbalance. Each of the muscles that surround a joint work together with opposing force that keeps the bones of the joint centered for optimum movement. If one or more of these muscles becomes weaker, stronger, looser, or tighter than normal, you have a muscle imbalance and joint movement can be limited.
What causes a muscle imbalance?
A muscle imbalance is often the result of:
- natural development
- certain activities of daily life
- bad posture
- an unbalanced exercise program
- exercising with improper form
Antagonistic muscle pairs are basically partners: One is responsible for pulling, and one is responsible for pushing.
When one (the agonist) contracts, the other (the antagonist) relaxes. This allows for full joint motion.
You can see this in action when you’re drinking water out of a bottle.
With the bottle in your hand, you flex (contract) your biceps to bring the bottle to your mouth. As your biceps contract, your triceps relax.
If either your biceps or triceps is developed more than its counterpart, you might not have full range of motion. In some situations, the more developed muscle may contract more and tighten up.
What are the effects of a muscle imbalance?
Strengthening your muscles is generally beneficial. However, if you over-focus on some areas of the body while neglecting others, you may end up with a muscle imbalance.
Muscle imbalances can lead to physical issues, such as:
- limited mobility
- unbalanced appearance
Muscle imbalances can also result in instability. This can lead to an increased risk of injury, including damage to:
- connective tissue
How do you fix muscle imbalances?
Everything in your body is connected, so something that impacts one part of your body affects — in either a major or minor way — everything else.
Your first step in fixing a muscle imbalance is identification.
Muscle strength and endurance testing
One method of identification is biometric testing. This method uses a machine to measure muscular contractions which can reveal strength deficiencies and muscle imbalances.
Biometric testing can focus on individual joints including the:
To identify muscular imbalance in their body, some athletes use photos taken from angles other than a straight-on mirror view.
This helps them see where their body is symmetrical and where they may have some size imbalances. These photos can help identify imbalances in muscle pairs affecting:
- head position
- hunched shoulders
- pelvic tilt
- leg rotation
Correcting imbalances with exercise
Imbalances can often be corrected through exercise.
A 2015 studyTrusted Source on elite fencers showed that the heavy use of lunging while fencing results in an imbalance of the lower and upper limb muscles.
By improving global muscle balance, the fencers’ lower extremity balance was improved during sport.
Another step for avoiding or fixing muscle imbalances is making sure that your exercise form is proper.
Check your form with an exercise professional (such as a trainer or coach) or by looking in the mirror while you work out, to make sure you’re working your body in the right way.
One way to avoid exercise-induced muscle imbalance is to focus on function and the whole body.
Avoid trying to build huge muscles in one area. For example, if lifting weights or performing a specific exercise like a lunge, always do the same number of reps on both sides of the body.
For proper movement, your opposing muscle groups must coordinate with each other. Proper coordination for normal movement and function is dependent on these opposing muscle groups being in balance.
Muscle imbalance can result in:
- limited mobility
- unbalanced appearance
If you’re experiencing muscle imbalance, you may be able to address it via targeted exercise. Consider working with a trainer or physical therapist. They can help you diagnose and address any imbalances you may have.