The royal couple and Prince Harry cheer on runners at London Marathon

What's better than crushing a tough race and seeing your loved ones on the sidelines? Seeing Prince Harry and the Duke and Duchess of Cambridge on the sidelines!

(We imagine. The most strenuous exercise this reporter has done today is a coffee run.)

UK Press via Getty Images
Prince William; Catherine, Duchess of Cambridge; and Prince Harry give a round of applause at the 2017 London Marathon.

The royal trio kicked off the 2017 London Marathon on Sunday (they got to press a large button!), then camped out at a cheering point to support the runners. Officially, they were representing Heads Together, their mental health initiative and the London Marathon's official Charity of the Year.

Unofficially, they were nailing the cheerleader game.

They flashed the requisite sports gestures ...

The duchess gives the marathon two thumbs up!

... They donned giant foam fingers ...

... They kept the people hydrated ...

AFP/Getty Images
When the royal couple offers you a drink, you should probably take it.

... The people kept them hydrated ...

Getty Images
Watch out, Prince William!

... They awarded medals at the finish line ...

... And they doled out high-fives to even the most, ahem, interesting characters.

AFP/Getty Images
This photo is, dare we say, amazing.

More than 40,000 people took part in today's 26.2-mile race. Many were wearing headbands in support of Heads Together, William, Kate and Harry’s campaign to end stigma surrounding mental health.

Their support of the cause has taken a personal tone lately, as both William and Harry have come forward about their struggles to cope with the untimely death of their mother, the late Princess Diana.

RELATED: Prince William admits he and Prince Harry should've talked about Diana's death

Harry, the Patron of the London Marathon Charitable Trust, presented the elite runners in the marathon with trophies, and good (and meaningful) times were had by all.

The duke and duchess were there to make some noise.

Congrats to the runners on a spectacular achievement!

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