The trio headed to Queen Elizabeth Olympic Park's London Marathon Community Track, where they met with 150 volunteers from the Heads Together mental-health organization who were training for the 2017 London Marathon, which will take place on April 23.
Kate, 35, rocked a Perfect Moment red puffer jacket, black skinny jeans and black sneakers for the event. William, 34, wore a navy sweater over a white button-down shirt, gray pants and blue shoes. Harry, 32, sported a midnight blue ski jacket, navy chinos and gray sneakers.
Harry came in first place, William placed second and Kate finished last. At the end of the race, the Duke and Duchess of Cambridge, who share kids Prince George, 3, and Princess Charlotte, 21 months, embraced in a sweet hug.
"We want to normalize mental health," William told the Heads Together runners at the Copper Box Arena after the race. "We want to get people talking about it, to make it more normal and to reduce the stigma. What you are doing and having so many of you here today, you've already seen the benefit of joining in by being part of this marathon. We want to make it a mental-health marathon."
"You are crucial to making this happen and we can't do it without you," he continued. "We really hope your training goes very well. Good luck with the training and we look forward to seeing you on the big day."
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