Different Arm Sizes

Nobody is truly symmetrical and every single one of us has a larger side to the body. This would typically be the right hand side of the body - irrespectve of whether you are left or right handed. I believe this may have something to do with the way blood circulates in the body from the heart on the left. The left ventricle and atrium chambers of the heart are massive when compared to their equivalents on the right. Blood is pumped under massive pressure from the left and branches out that way, so the return circulation on the right hand side will see more blood pooling on the right because return circulation is partly passive. Imperceptible, yes, but possibly enough to make a diffference.

None of that is important really, except to say asymmetry is natural. However, how we train can make this asymmetry worse. The solution to correcting asymmetry is to base all training on the weaker side's abilities and to do more isolation training.

Use isolation exercises as much as possible - dumbells rather than machines - cables rather than machines, barbells rather than machines, etc. If the weak side tires after 9 reps, but the strong side could still continue repping - stop. This way, the stronger side will not get any stronger until the weak side strengthens. The weak side will strengthen as all muscles do when trained properly - and it will eventually become stronger than even the stronger side was when you started out. When this crossover happens both sides of the body will continue at the same rate.

Muscle size and strength is largely determined by exercise intensity - how hard you train. If you only train as hard as the weaker side can manage, that will determine your strength and muscle size on both sides. The weak side will get stronger and the stronger side will stagnate - until the weaker side catches up.

This is hard to believe initially, but it always happens and most people experience this when they first start lifting weights. The size and strength of your muscles are closely related. Once you have reached a stage where strength has balanced your strength potential for both sides of the body becomes the same.

Size of the two limbs will always differ - but it should not be very obvious any more and this is natural. Every professional bodybuilder has different arm circumferences, as does every trained athlete. But that is more anatomical than anything else - the muscles are actually shaped slightly differently. Mathematical perfection is not biologically possible, so perfect symmetry does not exist in animals.

The key is to focus on the weaker side through isolation exercises. If you have to do each side separately for a particular exercise, such as cable lateral raises, do the weaker side first. Whatever reps and poundages you used for that arm must be replicated for the stronger arm, even if it can do much more.

It will work, unless your exercises are not making you stronger (which would mean you are not training effectively).

Idai Makaya
www.idaimakaya.com