It’s that time of the year again, to take a step back in time to remember this year’s Dextro Energy Triathlon ITU World Championship Series through the eyes of some of the world’s best sports photographers. They were on hand to capture every twist, turn, and colourful moment in the each and every world series race, but now it’s your turn to decide the official ITU Photo of the Year by voting on your favourite image below. Each weekly winner then earns the right to appear in the ITU Photo of the Year final. In addition to the contest, readers will hear from each event photographer about their favourite shot from the event, which will be published alongside the winning pictures from each week.

In week six of this competition, we revisit one of the most popular events all year, Lausanne. Both the ITU Elite Sprint Triathlon World Championships and Team Triathlon World Championships were captured by photographers Delly Carr and Janos Schmidt.

In the sprint races, Chile’s Barbara Riveros Diaz outsprinted Australia’s Emma Jackson to win her first world title, and the ITU World Championship for Chile. Read the race recap and watch video highlights here. In the men’s race, Jonathan Brownlee successfully defended his title, beating Javier Gomez and brother Alistair Brownlee over the line. Read the race recap and watch video highlights here.

Then came the mixed relay world titles. It was a huge year for the format, which was introduced in 2009, with confirmation it was accepted into the Asian Games and Commonwealth Games. And these world titles were also a resounding success, with a record 35 teams representing 28 countries starting and the star-studded Great Britain dream team, with Jodie Stimpson, Jonathan Brownlee, Helen Jenkins and Alistair Brownlee taking the title. But it wasn’t just the numbers, it’s evident in these finalist shots just how much passion and excitement the athletes have for the format. Read the race recap and watch video highlights here.

Remember to scroll to the bottom of the images and vote for your favourite, to determine which image from Lausanne makes it into the final of the 2011 ITU Photo of The Year.