"When I was a child, I was like a monkey and loved to climb trees. I like the Spartan Race because it combines cross-country running with tests of endurance," says Zhao.

"Even though I'm good at running, I still need to build up my strength for the race. Everyone has to overcome their personal weaknesses to make it to the finish line."

For each of the obstacles in the Spartan Race, a warrior is only given one attempt to complete it. If they fail an obstacle, they are handed a punishment of 30 "burpees" - a push-up where the chest touches the ground followed by a jump in the air with both hands held behind their ears - before they are allowed to try again. Elite group and Age group warriors have to finish the obstacles alone, while open group participants are allowed to help each other.

Competitor Xu Wanwei opted to try a new approach in the recent Spartan event in Beijing. In her first attempt at cracking the Women's Elite Group event, Xu tried to achieve the best time possible by opting to bypass obstacles she failed on her first attempt rather than spending time on punishment rounds.

Aiming to achieve a better result in this competition, she planned to overcome all the obstacles along the course to give her a better chance at qualifying for the Spartan World Championships. While the former national athlete failed four obstacles during her first Elite event, on this occasion she initially failed three obstacles. After repeatedly failing to overcome each hurdle, she opted to repeat the series of penalty burpees before trying to overcome the obstacle once again. After several attempts at each obstacle, she finally overcame each hurdle.

"Last time I took part, I failed to get a good result. But this time I came mentally prepared to conquer all the obstacles and tried to figure out techniques to overcome them in advance," says Xu, who was named a Spartan ambassador in February.

"To complete the Spartan Race, you need to be able to run long distances, and also have strong muscular endurance," says Xu. "You also need to assign your strength rationally."