With his short shorts, sparkly tank tops, frizzy hair and flamboyant personality, Simmons created a fitness empire. He preached positivity, portion control, moving your body — and having fun.

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More than a 100 years ago, doctors thought that too much running or other vigorous activity could harm us. Marathoner Clarence DeMar proved them wrong.

All those daily activities we'd rather avoid — taking the stairs, cleaning the house, etc. — have a big metabolic payoff. Non-exercise activity thermogenesis can help manage weight and boost health.

The new approach aims to promote overall fitness instead of focusing on specific exercises, and the devices will also give Guardians feedback about mental health, balanced eating and sleep.

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Exercise is important, but balancing exercise with mental health and your own body confidence can be a tricky thing to pull off. These tips can help you along your fitness journey.

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A personal trainer and trauma specialist explores how a mindful approach to strength training can help people heal emotional trauma.

A year ago, as the pandemic began, fitness instructor Joe Wicks started a daily exercise class for kids on YouTube. The videos became popular with kids and their parents. Now the series is ending.

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Paleoanthropologist Daniel Lieberman says the concept of "getting exercise" is relatively new. His new book, Exercised, examines why we run, lift and walk for a workout when our ancestors didn't.

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COVID-19 safeguards have created a black market for gyms.

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Swimmers, runners, weight-lifters are getting creative with home exercises. Out-of-work fitness instructors are doing tricky math: whether to offer their hard-earned skills on the Internet for free.