To answer this question, I reached out to five elite ultrarunners who have logged thousands of miles in triple-degree temperatures. Here are the hats they鈥檒l grab this summer when heading out to train or race.
Matt Hart: Mountain Hardwear Quasar Running Hat

I caught up with Hart after he聽spent the weekend training for up to six hours per day on the Hardrock 100 course in Silverton, Colorado. His pick, , is light, super-breathable, and quick-drying. Hart also appreciates that the UPF 50 hat is malleable and packs down to next to nothing. 鈥淚 can put it in my waistband,鈥 he says. On top of breathing well, it features Mountain Hardwear鈥檚 Cool.Q ZERO technology, which actively cools the user鈥檚 head when wet. 鈥淚 don鈥檛 know how it works on the scientific side,鈥 Hart says. 鈥淏ut I can actually feel it cool my head down.鈥
Jeff Browning: Patagonia Duckbill Cap

, the Zion 100 course record holder, has used the exclusively since he started running ultras 15 years ago. 鈥淚 found an old one in a secondhand store in 2002 and wore it out, then found another, and finally talked Patagonia into bringing it back two years ago,鈥 Browning wrote in an email. An airy mesh webbing is built throughout most of the hat, so it聽protects your head while still letting in plenty of air, Browning wrote. 鈥淭hat mesh material is great for dipping in water (creeks, rivers, etc.) to keep your head wet in the heat.鈥
Stephanie Howe: The North Face Better Than Naked Visor

, who won the 2014 Western States 100 in blistering heat, prefers over any hat. 鈥淚t shades my face, it鈥檚 light, and it doesn鈥檛 trap in heat like a hat. I never wear hats because so much heat loss is from the head. You don鈥檛 want to trap that in,鈥 Howe wrote in an email. She suggests purchasing a light color to minimize sun absorption.聽
Max King: Straw Cowboy Hat

This year鈥檚 100K world champion,聽Max King, usually wears a trucker聽hat when he runs because he prefers the non-teched-out look. But when it鈥檚 really hot, he breaks out the . 鈥淜eeps sun off the face, head, and neck better than anything. It鈥檚 super-breathable聽and looks badass,鈥 King wrote in an email.
Jenn Shelton: Patagonia Duckbill Trucker Hat

Ultrarunning legend Shelton wore the (a burlier version of Browning鈥檚 pick)聽for four eight-hour days while attempting an FKT on the John Muir Trail in 2014. 鈥淲e are still friends.聽So that must mean it鈥檚 a good hat,鈥 Shelton wrote in an email. On top of making her 鈥渇eel like a Lego man鈥 when she wears it, Shelton likes that it keeps the sun off her face but doesn鈥檛 make her overheat.