Halloween falling on a Thursday meant even more costume photos on social media, given the Throwback Thursday theme.
Several Olympians and Olympic sports organizations took part on Twitter and Instagram, among other outlets.
Here’s a sampling of postings:
Four-time Olympic track and field champion Allyson Felix in a throwback:
Norway’s two-time Olympic champion javelin thrower Andreas Thorkildsen:
Members of the USA Hockey National Team Development Program:
USA Volleyball staff:
Two-time Olympic champion snowboarder Shaun White in what appears to be a throwback with his brother and sister:
Three-time Olympic swimming champion Rowdy Gaines:
Eight-time Olympic medalist short track speedskater Apolo Ohno (second from right, it appears):
2010 Olympic figure skater Rachael Flatt:
2010 Olympic figure skater Jeremy Abbott:
2010 Olympic bobsledder Steve Langton:
Finally, the founder of the modern Olympics, Baron Pierre de Coubertin: