Giveaway prompt: Marathon

John watched in amusement as Sherlock and their client jogged around the sidewalk loop in the park. Sherlock had left his coat with John, sleeves rolled up as he kept pace with Henry, the insurance CEO, training to participate in the upcoming marathon next month. He was putting on a front, Sherlock had told John, by running the 5000km for charity donations. The two were now engaged in breathless conversation, exchanging details and advice. As the businessman's training session came to a close, he slowed and stopped near John's bench, tipping his entire torso back to drink energetically from a water bottle. Sherlock was right on his tail, and John handed him a bottle he'd brought along for the day.

"You're quite good at this," Henry said after he'd had his fill, his breathing returning to normal after a bit. He gave Sherlock a friendly, encouraging slap on the back and started a few cool-down stretches. "Maybe you should enter into the marathon too!"

Sherlock retrieved his coat and re-donned it, smirking at the compliment, "I suppose all those nights chasing after criminals through the back-streets of London has some secondary benefits. Perhaps I'll consider it if nothing else of importance interferes."

John had to stifle a giggle at the idea of Sherlock in a tank-top and running shorts.