Tour de France winner Chris Froome rides for GB again, as does fellow GB rider Geraint Thomas, who crashed out dramatically in the final descent of the men’s road race.
In the women, Emma Pooley rides for Britain, joining a field that includes road race winner and time trial favourite Anna Van der Breggen. She’s aiming to becoming the first rider, male or female, to win both the Olympic road race and time trial at the same Games.
Here’s everything you need to know.
When is the Rio 2016 Olympic time trial live on TV?
Both races use much of the same circuit used during the road race, with both the Grumani and Grota Funda climbs making an appearance here. The men do two laps of the course, a total distance of 54.6km, while the women’s race is one lap totalling 29.9km. At the weekend, BBC commentator Chris Boardman criticised the course after women’s race leader Annemiek van Vleuten suffered a horrible crash just before the finish.
The Time Trial is known as the “race of truth”, but for most practitioners it’s actually a race of uncertainty. Riders set off individually and attempt to set the fastest time for the course. The general rule is that if you’re going at a pace you’re certain you can sustain to the finish then you’re not working hard enough to win. The ideal time trial is ridden alone, in a state of anxiety.
Because each rider sets off alone there’s no opportunity to nestle in the slipstream of other riders and stay out of the wind, which makes aerodynamic equipment vitally important for time triallists. Riders wear one-piece skinsuits without seams or creases in order to minimise drag, and a finned helmet that smooths the airflow over their head. Bikes are similarly aerodynamic, with disc wheels rather than spokes, and long, low handlebars that extend out in front of the bike, forcing the rider to tuck into a low, elongated position.
Position is vital in time trialling in order to optimise the strength of the rider’s legs but minimise aerodynamic drag. Riders adopt a flat-backed, head up position, and will move around as little as possible. You can tell when a time triallist has gone too deep into energy reserves as they begin to wriggle from side to side in an attempt to use their body weight on the pedals. Backs hump and heads lower in exhaustion, turning an elongated helmet from a helpful fairing into a hindering sail.
Who are the favourites?
The past masters of this discipline are Britain’s Bradley Wiggins, Germany’s Tony Martin and Switzerland’s Fabian Cancellara, but as the years creep up, Britain’s Chris Froome and Holland’s Tom Dumoulin are seen as the heirs apparent. The 54km men’s time trial race is up in the air – Wiggins has chosen to ride the track events instead of the road, Martin and Dumoulin are both recovering from injuries and Froome may be tired from his Tour winning efforts. Keep an eye on Belarussian Time Trial World Champion Vasil Kiriyenka if the beleaguered favourites aren’t on their best form.
In the women’s event, Britain’s Emma Pooley favours a hilly time trial, so the 30km women’s course might suit her, but it’s likely that her rivals will have better form. Keep an eye out for Anna van der Breggen (winner of the road race), World Champion Linda Villumsen of New Zealand and the veteran two-time gold medallist Kristin Armstrong from the USA.