Muggle Quidditch

Naginata jutsu

Naval Pentathlon

Netball

Newcomb Ball

Ninja Warrior

Northern Praying Mantis

Novuss

Obstacle Course Racing

Ocean Rowing

Offshore Rowing

Oil Wrestling

Oină

Okinawan Kobudō

Olympic Weight lifting

Open Water Swimming

Orange Races

Orienteering

Outdoor Handball

Outrigger Canoeing

Over the line

Oztag

Paddle boarding

Paddle Tennis