Six things you need to know about the World Championships team time trials

What exactly is the team time trial?

The team time trial traditionally kicks off the annual UCI Road World Championships. Teams of six riders compete against each other to set the fastest time over a given course. Both women's and men's events take place on the same day, which this year is Sunday, September 17.

The discipline is the essence of team work: squads must perfectly pace their effort and ensure that they do not drop weaker riders by riding too fast. Riders generally take it in turns to ride at the front, with stronger riders either doing more and/or longer turns at the front to drive the pace.

Finish times are given when the fourth member of the team crosses the line, so six-rider teams can drop two riders during the event.

>>> UCI Road World Championships 2017: Latest news, reports and race info

Why do they compete as trade teams?

Unlike the rest of the World Championships – the individual time trials and road races – team time trials are contested by trade teams rather than national teams. The reason for this is that team time trials require a distinct amount of training and experience to get right.

Riders in trade teams ride with each other throughout the season, including in TTT events in Grand Tours and other stage races. National teams simply would not have time to train together. It's also a nice bit of 'payback' for trade team sponsors to get some TV airtime at an official UCI event.

How come the winners do not get to wear a rainbow jersey?

Unlike the other disciplines in the Worlds, the winners of the TTT do not get to wear a rainbow jersey the following year. Instead, the winners receive a trophy and medals, and those in second and third places also receive medals. The national anthem of the country in which the winning team is registered will be played during the podium ceremony.

The winning team – all of them, not just those who competed in the TTT – have a small logo on their team kit the following year to denote that they are TTT champions. And if you are on the winning team but then change squads for the following season, then hard luck... you can't take it with you.

Which teams take part?

All WorldTour teams receive an invitation to take part, although it is not compulsory to do so. Professional Continental and Continental level (ie second and third division) teams can all take part as long as they have met the UCI's selection criteria.

The women's event is slightly different in that the top 15 UCI women’s teams on the UCI women team ranking are invited, although not all may accept the invitation. A further 10 teams can also apply to take part.

Who are the defending champions?

The 2016 team time trial world titles are held by Etixx-Quick-Step (now known as Quick-Step Floors - men) and Boels-Dolmans (women).

Previous winners since the event returned to the Worlds in 2012:

2016 - Etixx-QuickStep (men); Boels-Dolmans (women)

2015 - BMC Racing Team (men); Velocio–SRAM (women)

2014 - BMC Racing Team (men); Specialized–lululemon (women)

2013 - Omega Pharma-QuickStep (men); Specialized–lululemon (women)

2012 - Omega Pharma-QuickStep (men); Specialized–lululemon (women)

What's this year's team time trial course like, and when does it take place?

This year's TTT championships take place in Bergen, Norway. Both men's and women's teams tackle the same hilly course around Bergen, which is 42.5km (26.4 miles) long and includes the testing 3km Birkelundsbakken climb.

The women's TTT takes place on Sunday, September 17, between 12:05-13:55 (local time), with the men's teams riding between 13:35-17:25 that afternoon.