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Lakewood, CA
A 32-year-old male asked:

Is it normal for dominant arm bicep and triceps to be slightly large than my left arm. muscle imbalance? no weakness. neuro for emg to check als?

3 doctor answers10 doctors weighed in
Dr. Mark Fisher
Neurology 31 years experience
Yes: I wouldn't call it "normal." It is, however, practically universal.
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Dr. Olav Jaren
Neurology 21 years experience
Dominant arm strongr: Since ALS is a painless weakness, and you do not have weakness, ALS should not be considered the cause. If you use the dominant arm for weights and do not use the other arm, the muscles will be different sizes. Normally they are pretty close. The easiest way to sort this out is to see if you can make the left arm stronger. That would rule out an illness.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Bennett Machanic
Neurology 54 years experience
Not uncommon: OK to have some imbalance and asymmetry, and is NOT a sign of ALS, unless you have progressive weakness, muscular atrophy, and fasciculations all together.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Nov 28, 2017

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