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The Goldilocks of running tops.

We're well aware of the problem facing runners in cool climates, seeing most performance tops leave you chilly at the run's onset, only to get hot and sweaty after a few miles. Solving this issue once and for all, the Under Armour Men's Reactor Long-Sleeve Shirt maintains an optimal body temperature with its ultralight fabric paired with stretch-mesh panels for breathability and full range of motion. This material actively pulls perspiration off your body, meaning it facilitates the body's natural cooling process as you push yourself on the road. It's finished with an anti-odor treatment that keeps funky odors from building up after high-intensity efforts.

  • Regulates your body temperature during runs in chilly weather
  • Ultralight polyester wicks sweat while insulating you from chilly air
  • Stretch-mesh panels boost breathability and enhance range of motion
  • Anti-odor treatment prevents funky build-up after sweating
  • Semi-fitted design sits close without restricting motion
  • Reflective logo for extra visibility late at night
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