Muscles that interfere with other muscles?

Question

i was watching something on tv where some karate dude was talking about how building up your biceps interfere with some other muscle (the one that helps you push things). is there any truth to this?

Answer 1

I'm not sure what he means by "interfere."  

However, in the case of two muscles that oppose each other, such as the biceps and triceps example which you mentioned, if you over-train one set (biceps), you can become susceptible to injury in the opposing set (triceps) if you don't train both muscle groups.

Hope that helps!