Olympic athletes come in all shapes and sizes.

And that couldn't have been more apparent after Simone Biles posted a photo on her Twitter account.

In the photo, the 19-year-old gymnast can be seen standing back to back with Olympic volleyball player David Lee.

Lee, 34, stands at 6-foot-8 -- two whole feet taller than Biles, a three-time world all-around champion who is 4 feet 8 inches tall.

"Size difference in olympians doesn't matter," Biles captioned the photo.

The Opening Ceremony for the 2016 Olympic Games in Rio is Friday.