Despite the rumors going around about her pregnancy, Duchess of Cambridge Kate Middleton hasn't slowed down in public appearances, the latest of which involved her Heads Together campaign, which aims to fight the stigma around mental health.

Promoting the cause, Middleton donned a pair of boxing gloves for a boxercise session. The royal threw some punches at former professional boxer Duke McKenzie in between laughs and smiles. McKenzie said via Telegraph that the mother of two had a "wicked punch."

Joining Middleton in the cause are Prince William and Prince Harry, who also showed off some boxing moves at the event. Boxercising is said to be a great way to improve mental well-being. The royal trio is joined by eight big mental health charities.

"Too often, people feel afraid to admit that they are struggling with their mental health. This fear of judgement stops people from getting the help they need, which can destroy families and end lives," Middleton said via Telegraph.

"Heads Together wants to help everyone feel much more confident with their everyday mental health, and to have the practical tools to support their friends and family," she added.

Middleton is rumored to be pregnant with Prince George and Princess Charlotte's little brother or sister, although no confirmation from the Kensington Palace has been made about it.

Despite this, media outlets continue to report about Middleton's third pregnancy, some even claiming that she is having twins. There are other rumors, however, saying that she and Prince William are planning to have their third child after their travels.

Middleton is allegedly sitting out her trip to Brazil with Prince William this August in an effort to avoid the Zika virus, which affects babies still inside their mothers' wombs. Because of this, the Duke of Cambridge will be the only one going there.

This is said to be an early precaution being taken by Middleton so that her third pregnancy will be smooth and that her baby will be healthy.