Recent studies show that training in the heat has asimilareffect on the body as training at altitude.But that doesn't make it pleasantor, in some cases,safe. Here are eightproducts to help you keep your core temperature down and your performance up as you adapt to summer weather.

MissionInstant Cooling Towels ($18)
are designed to absorb sweat and bring your temperature down after a workout. When soaked in water and rung out, the proprietary fabric cools to 30 degrees below the average body temperature—think about it like draping a bag of ice around your shoulders.

Medical Supplies and Equipment Company Hydrotherapy Tub ($5,255)
Ice-water immersion is the most effective treatment for heat-related illness in athletes, and it's a useful rehab technique, too. Medical Supplies and Equipment Company (MSEC) makes , similar to the kind you see in the locker room scenes of sports movies.

SolumbraUltra Athlete Shirt ($99)
Solumbra makes a wide range of sun-protective clothing, including a full body suit used by many ultramarathoners to run the Badwater 135-mile race in Death Valley. The was constructed with huge vented panels, and the fabric is rated at 100+ UPF.

HammacherEvaporative Cooling Cap ($29)
From the outside, the from HammacherSchlemmer looks like a dorky hiking lid. But the fabric and technology were developed by the military’s go-to source for cooling gear. The hat was designed to be submerged in water, which is absorbed into the inner liner and vaporizes slowly over a few hours, keeping your dome 20 degrees cooler than the air temp.

Columbia Zero Rules Short Sleeve Shirt ($39)
Columbia created an entire line of proprietary fabric for the sole purpose of keeping athletes cool. The is made from the company’s proprietary Omni-Freeze fabric, which dips to a lower temperature when activated by sweat. This shirt is also rated to 30 UPF.

Patagonia Nine Trail Hydration Vest ($79)
Hydration. Just about any water bottle will do, but if it’s really hot, you’re going to want more than a liter. was designed for long hauls with room for a two-liter bladder or multiple soft bottles.

Eddie Bauer Quantum Shirt ($60)
The is marketed as “the world's only sweat-activated venting system.” That meansthis shirt comes with built-in sweat vents—laser-cut in places where you're likely to get the hottest—that open when they get wet.