Free under the Pexels License (https://www.pexels.com/license/) — no attribution required, credit appreciated.
- softball.jpg — Erik Mclean — https://www.pexels.com/photo/7561177/ (optic yellow softball on grass)
- basketball.jpg — Reinis Brūzītis — https://www.pexels.com/photo/34688571/ (ball on blue/hardwood court)
- volleyball.jpg — Critical Smith — https://www.pexels.com/photo/32602956/ (ball on red indoor court)
- running.jpg — Sarawut Horpetch — https://www.pexels.com/photo/31756484/ (running shoes on red track, 400m lane)