Kylie Jenner Works Out In Sports Bra on Yacht in Mediterranean

Kylie Jenner is always going to keep it tight ... even while on a yacht in the Mediterranean, where she got in a workout while wearing a sports bra.

Check out the video from Kylie's onboard exercise ... she's in a black top and spandex shorts, maintaining her fitness routine on a reformer Pilates machine ... working her arms and her legs.

Kylie is on a mega yacht anchored off the coast of Sardinia ... she's with some friends and it looks like she's unwinding after a wild few weeks with boyfriend Timothée Chalamet.

KJ and TC cheered on his beloved New York Knicks on the way to their first NBA championship since 1973 ... and now it seems it's Kylie's turn to have some fun.

For Kylie, that means soaking in the Mediterranean sun ... while making sure her curves have the ultimate definition.