This is the hilarious moment zoo staff tricked a volunteer into a sit-up contest with a walrus during a show.

Footage shows the enthusiastic man performing crunches while a female staff member guides the tusker off to the side of the stage in Guangdong, China.

Meanwhile, the host continued speaking while helping the animal hide behind the stage on July 14.

The crowd began counting the man's repetitions, unaware that his ‘opponent' had already left.

Moments later, the host approached him and asked if he could still continue, to which he energetically responded 'yes' before carrying on with the exercise.

This elicited laughter from the crowd as the man held his head and lay on the pink mat, continuing to do sit-ups.