IQ is and has always been mostly Genetic, so neither of those would effect that much. There almost certainly give people brain damage/not fully formed brains or turn them into drooling retards, but that is a separate type of idiocy than pure IQ even if the test measuring it cannot tell the difference.

The difference between someone who is genetically just a lanky boy being unable to gain much muscle, and someone who has a medical issue that prevents them from doing the lifts to gain muscle.