The Olympic omnium tests cyclists in a variety of disciplines over two days of racing.
The first event is a scratch race, similar to a road race – the riders set off together, all on the track at the same time, and the winner is the one across the line first. Men race over 15km, women over 10km.
Next up is the individual pursuit (4km for men, 3km for women), with each rider competing once. The leaderboard is based purely on times against the clock.
The third race is the elimination race. The last rider across the line every two laps is eliminated, until only one remains.
Day two kicks off with a time trial – 1km for men, 500m for women – and then there’s a 200m flying lap against the clock.
The omnium culminates in the points race, which can have a huge bearing on the final rankings. Riders win points by being in the top four in the intermediate sprints, or by lapping the field, and these points are simply added onto the totals accrued over the previous two days, so quite large deficits can be overcome.