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Zach Boivin remade himself into an Ironman inspiration.
Falling into your body's instinctual gait maximizes efficiency, a study says.
That slow plod could be doing more harm than good.
Everything you need to know to run, swim, and bike to victory.
How he applied a Spartan mentality to his fitness.
Power up your workouts with these moves.
Bulletproof your joints and become a better runner.
Find out about these training mistakes.