Derrick Henry Shows Off Massive Biceps During Intense, Shirtless Workout

working on the bodDerrick Henry is proving once more he's superhuman ... showing off a pair biceps on Wednesday that'd make even the biggest pro bodybuilder envious.

It was apparently arm day for the NFL superstar on Wednesday ... and in a video of his sweat sesh posted by his trainer, you can see the running back had a whole lot of bis and tris to work out once he got in the gym.

Henry -- sans shirt -- got a pump in through various different exercises ... including a bunch of curls with heavy weights -- and some pushups with a plate on his back.

4/24/23

PUSH THROUGH THE PAIN Instagram / @theshanemcmahon

Of course, seeing Henry toss around iron is nothing new ... the 6-foot-3, 247-pound tailback…