Work your whole body and give emphasis in your program to the muscles and muscle groups you see are biggest on your goal physique. Simple as that. Nothing wrong with doing it from day 1

I believe just do it from day one. If you want big legs and big arms, start working towards it now. You'll build your base anyways as long as you're training everything anyways. You may even want to limit training on certain body parts or muscle groups to match your physique goals.

people who say you need to build a base before bodybuilding are just giving an ever- receding smidge of recommendation for powerlifting, because to say that you can hop directly into bodybuilding would mean having to confront the realization that they got sucked into the powerlifting meme and wasted a bunch of time. rather than admit this, they say well I didn't waste that much time, cause there's value in building a base. no there is not. "just get stronger" is bs. train for your goals

same for the other pursuits. train for your goals from day 1. if you have zero athletic background at all and are very uncoordinated it could be helpful to play in a rec league in a random sport, or go throw around a baseball with a friend, shoot hoops at the park, go for runs etc. just something to build coordination/ athleticism. but build this base alongside working towards your goal.

name one other pursuit where people say they want X and people say "that's nice, but you should work towards Y for a few years first"

This presupposes a beginner on day 1 has any clue how to train for a particular aesthetic.

Like they might see an arm wrestler with big ass forearms and not realize their forearms are just especially big. They have big chest, back, legs, etc and just have especially big forearms.

So somebody bushwacking their own beginner physique program might just spam wrist curls at the expense of everything else.

Following a well rounded program gets you well rounded development while you learn what you are doing.

If someone works with a coach or trainer with a reference physique as a goal that's a different story.

There's nothing wrong with doing it from day 1. I think a lot of people mess it up though cause they are too young in their lifting journey to properly analyze what they are seeking in their dream body

I mean it always depends exactly what they're going for. But most physiques which aren't bodybuilders that a person might aspire to have, like an Olympic lifter - they don't have early intermediate biceps and triceps. For the random guy wanting to look like that, the Oly lifters' arms could, unfortunately, be what this guy's arms will look like well into the advanced level. 

If we're talking about a body part that's actually highly underdeveloped then I guess we could talk about gymnasts with jacked upper bodies and slim legs. I mean if you don't care about legs then you don't care about legs. I'd personally still want to see somebody train their legs until they're out of the novice stage just because I associate that baseline of lower body strength as kind of a metric of health. 

It's worth aiming for your goal from day one. If you start seeing progress toward your goal and you decide you don't like it, you can always adjust later. Example: if your goal was to have overdevelopd arms, but you started seeing your arms get out of proportion and actually realized you don't like the imbalanced look, you could just start de-emphaszing arms and focusing more on getting other muscles to develop and "catch up."

Bottom line: it's your body, build it how you want.

That all depends on your goals. A bit of development throughout your body is good because it prevents imbalances and provides an overall athletic benefit, but it's not strictly necessary.

Here's a video from Basement Bodybuilding talking about it: "But I'm weak, don't I need to build a strength base first?"

Initially the thought might be "train the whole body", but in working with motivation, I think someone is more likely to stick with training if they train how they would like.

So they should train what they want. Interest and adherence is going to be higher.

If they catch the workout bug, then they will move to more full body stuff.

Telling someone to "train your whole body first" if someone has limited specific goals is asking someone to take a lot of time doing stuff that they don't want to do.

To me it is analogous to someone saying they want to learn how to make good Spaghetti Sauce, and telling them they need to first learn the French Mother Sauces so they have a good base.

BB is about crafting your body to your favorite aesthetics. There is actually no point in "building your base first", it will just do more harm then good. If u want the aesthetics of big chest and arms, why throw arms in the end of push and pull days, and why not do less shoulder pressing and more chest pressing ?

Genetics plays a large role in what is and isn’t a possible outcome. A certain aesthetic may be permanently out of reach unless you’re genetically predisposed to it.

Insertion points and skeletal structure are what they are and the best you can do is maximise potential. Understand that and accept your limitations because some of them are never going to change.

Just lift bro

You should immediately start pursuing your goal. Some of us more experienced folks will only say otherwise as cope for not having done that ourselves

I think striving to look like a subset of people who are already genetically inclined to look a certain way is going to be an exercise in futility.

Everyone, outside of very specific medical limitations, can add muscle and get lean. Almost nobody can look like somebody else.

So, it kind of depends.

Focusing on your natural aesthetic strengths is pretty likely to give you great results the fastest, but A) most beginners don’t necessarily know what their natural strengths are until they start getting stronger and have a decent base, and B) the aesthetic you want might not necessarily align with your natural strengths.

So, nothing wrong at all with going after a specific build from day 1 depending on your plan and experience.

But it’s worth considering just getting stronger and consistent with lifting will greatly improve your aesthetic anyway, in addition to giving you a great deal of information about what your body best responds to. Oftentimes, this is the quickest way to a goal anyway

Go after what you want right off the bat. The “base” is horse manure. A base is built no matter how you skin the cat, as long as you get after it hard enough.

I agree with the others that said go for your goals straight away, but I think there is some merit to doing a course of powerlifting or strength training, because there are some good training habits you can get from it: - it teaches you to progress, because it's kind of the whole point to get stronger  - the training tends to be 'well calibrated' because back off work tends to be a set percentage of 1RM and the accessory work is usually just done to failure. So you pick up a feel for what quality volume should feel like. - there's far less bullshit in powerlifting. Because progression is so explicit compared to bodybuilding (it's obvious if you put weight on the bar or not), training methods that don't work can't hide, and so powerlifting has much less of the grifter training methods that bodybuilding tends to produce (e.g. superslow, power factor training, 30-10-30, max contraction training, all that bullshit). So you get a more grounded experience of training.