The 21-Day Transition: Day 3 Workout

Challenge Accepted: Spartan Ultra Iceland, Part 2

Challenge Accepted: Spartan Ultra Iceland, Part 1

All the gear you need to crush a Spartan Ultra in Iceland

Challenge Accepted: Spartan Ultra Iceland, Part 3

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Fitness star Anna Victoria's top tips for a successful body transformation

The best yoga moves to improve shoulder flexibility

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Exclusive video: Miles Teller and Josh Brolin talk intense firefighter bootcamp for ‘Only the Brave’

How to commit to athletic excellence, according to Nike trainer Joe Holder

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Paige Hathaway shares her top secrets for social media success

Gut-Check Workouts: 8 quick routines to fight weight gain

The upper-body push/lower-body pull workout

The upper-body inner-beast workout for big, strong, and shredded shoulders, pecs, and triceps

Theater of War: How actor Michael Kelly gained military muscle for 'The Long Road Home'

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'Men's Fitness' Guy School: The 101 on wine

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This healthy and delicious grilling recipe is perfect for your end-of-summer BBQ

Eliud Kipchoge is a perfect marathoner. Here's how Breaking2 scientists made him faster.

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