If volume is (sets x reps) x weight, then:
sets…reps…weight…volume
…3…3…400…3600
…8…5…100…4000
BUT we all know that the above isn’t gonna build muscle, at least not the second one. So my question is this: what’s the range that you can change the reps and sets? keep the weight close to the original? or do I have the equation wrong?
About 25-50 total (set x reps) repetitions per muscle group per training session, excluding specialized isolation stuff for small muscles.
But there are huge variations between different individuals and even between muscle groups for the same person, its more like a guideline.
[quote]Petrichor wrote:
About 25-50 total (set x reps) repetitions per muscle group per training session…[/quote]
but by that method, the second one has 40 total reps, while the first leaves room for many more 3x3 exercises, making the first much better for muscle gains. I understand you said that it’s more like a guideline, so I’m not sandbagging you here, but I’m just trying to clear this up.
Let’s pretend this is dealing with squats. let’s say that I can squat 400 pounds for 3 sets of 3. if I was going to remake my plan after being on it for 3 months, I couldn’t just go and squat 100 pounds for 8 sets of 5, even though the total volume is greater.
[quote] BUT we all know that the above isn’t gonna build muscle,
[/quote]
Why not? Lol. Maybe I missed the memo, but since when does lifting stuff NOT build muscle? 
Looking at your example, I’m pretty sure you could actually gain some mass with 8 sets of 5 reps after your 3 sets of 3 approach. Not that I believe in a formulae to calculate volume, but it sounds like a pretty similar effort to me. 
but the weight is so small. you’d need a 25 on each side to get that, as opposed to the original 3 45’s on each side.
I agree man, but this goes by the same logic as the psychological principle of conservation. When you have 2 identical glasses with the exact same amount of water in em, and you just pour one into a much larger, but few inches shorter glass, it can be hard to believe that you have the same amount of liquid in both. Same goes for your example, at least the way I see it.
hmm…maybe you’re right. not to say you’re wrong, but it’s hard to tell if you’re right with only 1 other person replying to this. I’ll wait it out, then most likely say you’re right. haha
i doubt its the volume that matters most.
you could have the biggest volume anyone has achieved in one day by resting and lifting small weights with lots of reps
in the end you could easily get in over 100 sets of 20 reps.
IMO dont forget the basic thing(the stimuli). your brain must realize it needs to build more muscle. light weights will only make it build a little more, heavy weights it will need to build more.
in the end its the food that mostly matters.
and it varies on the individual.
i also had read an article that suggested rep ranges around 8-12, but it also said that bodybuilders get the “pump”(not sure if its the same as the pump that probably all of us have felt at some time in the gym) and only during that short period are their muscles as big as they can be, whereas without the pump they seem smaller.
on the other hand those who go for strength with higher weights build muscles and are tight 24/7. as tight as they are during rest they will be as tight and big during … whatever.
or something like that, i dont remmeber fully cause this stuff doesnt interest me all that much personally
It has to do with the various kinds of hypertrophy each type of training induces. Typically bodybuilding training elicits more of the non-functional (dont get out the PC people on me for saying this!) muscle growth whereas heavy strength training typically increases neurogenic tone and a different type of hypertrophy (the technical term eludes me at this time 
) that gives you muscles that bad azz look of being dense, thick and tight all the time.
Someone correct me if I am wrong.
Basically it is just the overload principle that needs to be addressed right? You need to tax the musculoskeletal system as hard (and safe) as possible within as small a time frame as possible to get results.
That would make lifting 100 pounds 3 times in 45 seconds more efficient than lifting 1 pound 300 times in the course of a day.
Thats not to say someone should go into the gym and bench 1 set of 200 pounds for 3 reps and call it a day, as there are obvious problems with that as well.
This sounds a lot like Power Factor Training by Pete Cisco or John Little, or both. I found their theory to be a bunch of crap.
[quote]Eppert wrote:
If volume is (sets x reps) x weight, then:
sets…reps…weight…volume
…3…3…400…3600
…8…5…100…4000
BUT we all know that the above isn’t gonna build muscle, at least not the second one. So my question is this: what’s the range that you can change the reps and sets? keep the weight close to the original? or do I have the equation wrong?[/quote]
So there you have it. You just demonstrated that volume is not the only determinant of muscle growth.
In the 8x5, I would be amazed if you couldn’t handle at least 250 lbs, if you can nail 3x3 at 400. Your volume would be much higher, but your intensity would be lower.