Brittany Mahomes Continues Gym Workouts During 'Hardest' Pregnancy

Brittany Mahomes isn't letting her "hardest" pregnancy keep her away from the gym ... 'cause the Kansas City Chiefs superstar's wife is still working out in full force!!

Mahomes -- who's married to Patrick Mahomes -- shared her exercise session at the gym on Instagram ... weeks after she revealed she was pregnant with her third child.

The 28-year-old showcased her full-body sweat sesh ... and she looks good doing it, proving she wasn't playing around when it came to perfecting her Sports Illustrated Swimsuit bod.

What's impressive is that Mahomes is still able to train her body even with this being what she's considered the most difficult pregnancy out of all of 'em ... revealing last month she's experiencing "sickness, exhaustion" as well as skin issues.

Luckily for her, this might be the last go around. Patrick -- who signed a 10-year, $503 million deal in 2020 -- said he's done having kids after No. 3.