this shyt is not true
working legs gets your upper body bigger??? i need some links breh
Your body is system composed of different parts. If your real goal is total strength, then you should be doing comprehensive workouts. People mentioned a lot of good compound exercises--squats, dips, deadlifts, chin-ups, bench etc.
You should really incorporate more compounds if strength is your goal. If you isolate a muscle group and neglect the stabilizers you'll have nice looking muscles but a shytty "foundation" if you what I'm saying.
It'll help you get stronger, look more proportionate, and most importantly, it will ensure you stay safe when lifting.
There's no reason for you to be working out biceps three days in a row.
Your splits should be more comprehensive i.e. chest/back day, shoulders/legs, then maybe a "light" day that's more accessory workouts like core exercsies, isolated curls i.e. preacher curls, hammer curls, tricep exercises, etc.
I don't really have a super strict regimen but I have a goal in mind during my three-day splits to target/isolate certain muscle groups.
You could probably get away with doing core exercises everyday you work out, but again, if your goal is just to "look" bigger, by all means, isolate certain muscle groups, but if total strength is your goal, you should really incorporate more compounds.
Really look into doing a lot more deadlifts and dips though.