Cleveland Browns Star Myles Garrett Deadlifts Over 450 Pounds!

Check this out, James Harrison ... there's a defensive lineman who's throwing around a ridiculous amount of weight in the gym ... and it's super impressive.

Myles Garrett did his best impression of the former Steelers superstar Thursday ... posting a video of himself deadlifting what appears to be about 465 pounds with a trap bar -- multiple times!!!

Oh ... and for some of the reps, he's wearing a big-ass weighted vest loaded with 100 pounds.

Now, Garrett lifting heavy weights ain't exactly breaking news ... the dude threw up 225 pounds 33 times at the NFL Combine in 2017.

FYI -- only 2 other guys in the entire draft completed more reps.

Back in January, the Browns star also posted video of himself benching 425 pounds.

MG's still indefinitely suspended for swinging a helmet at Mason Rudolph's head ... so seeing him get after it hard in the gym is a sight for sore eyed Cleveland Browns fans who want Myles back on the field.

Garrett looks shredded -- and is obviously crazy strong -- but he's still got work to do if he wants to match feats of strength with the dude who once benched 500 pounds and pushed around an 1,800-pound sled.