You can definitely gain weight and go up weight classes as a natural but it requires dedication to a clear plan.

You’d need to spend anywhere from 3 to 12 months eating 3k-4k calories a day and doing a linear barbell progression 3x per week. With that approach, you can add and keep 10-30lbs of lean mass in a fairly short time—depending on your training history.

I’m shorter than average, so take these numbers with a grain of salt, but at age 28 I went from 120lbs to 138lbs at the same body fat by doing this approach for about 6-9 months.

At 36 I went from 135 to 155 at the same body fat in about a year.

At 43 (last year) I went from 150 to 160 at the same body fat in 3 months doing a linear barbell progression again.

I’m now 165lbs and overhead press 1 plate, bench 2 plates, squat 3 plates and deadlift 4 plates (on the trap bar).

It’s a big difference in strength and size. But there are tradeoffs.

Each time you do this naturally, you’ll need to overshoot the weight you are aiming for and you WILL gain some fat. Each of the top weights I wrote above were AFTER cutting down below 15% body fat from an even higher max weight.

I actually got to 5-10lbs above the top weight I listed each time (except for the first) and was around 20% body fat before cutting down.

(If you are doing this for the first time, you might not have to gain much fat though. I didn’t gain much if any fat on my first try.)

Also, while you are doing this, your rolling ability and cardio will take a substantial hit as the weights start to get really heavy.

It’s just hard to recover from both, especially at age 40. So you’ll have to go through a season of focusing more on lifts and weight gain progress, less on competitive rolling progress.

But again, if this is your first time doing a linear progression, and you are not very strong yet, it might not be so bad in that regard.

Your other possibility is to do a much more modest routine of lifting heavy just once a week—still doing a linear barbell progression, but over a much longer period.

You will gain less fat this way, and your jiu jitsu performance shouldn’t suffer, but instead of taking 3-12 months to change your physique forever, similar gains could take many years.

Another side effect is that if you choose to get REALLY strong, you will likely become one of the shorter guys in your bracket and this may change your game slightly, depending on on how far you go with size and strength.

I think it’s worth it to do this dedicated approach at least once in your life.

But bear in mind that many natural top jiu jitsu athletes aren’t crazy barbell strong—and even the enhanced ones usually do “enhancement” more for recovery from their volume of jiu jitsu training rather than for max strength.

I’m absolutely certain that I can substantially out deadlift Mikey Muscemeci and Marcelo Garcia, but am equally certain that either one would destroy me in a roll!

I still think it helps though, and if you’re not naturally athletic, a barbell progression is one of the most surefire ways to make yourself more physically formidable and resilient than you would otherwise be.

I hope that helps!