Re: How to get thin arms
Are your arms large with fat or muscle?
If they are fat, there may not be much you can do about it, other than losing fat in general, since your genetics determines the pattern of how you gain or lose fat (exercising a specific area to spot reduce is ineffective).
If they are muscular, avoiding exercising your arms will reduce the muscle. But why would you want to do that? Although if your upper body exercise overemphasizes arms, you may want to shift the emphasis to your larger muscles like chest (e.g. pushups, dips, bench press) and back (e.g. pullups, rows) to get greater usable strength and muscle growth to help burn fat even at rest.