Kyle's nonprofit, FITCO Cares, provides at-home fitness equipment for emotionally and physically wounded veterans.

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By helping popularize weight training, supplement and vitamin use, and fitness equipment -- whether in a gym, a school or a home -- Weider helped change the way the world looks at fitness and health, according to Parker.

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The fitness industry has an entirely separate type of January effect that sees a spike in sales of home exercise equipment, diet programs and gym memberships.

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