How strong are you?You'd probably be amazed to learn how much force your body's joints and muscles actually support on a daily basis. This interactive segment from Discovery takes you inside the body and explains how much strength your bones and muscles really possess.

Health and exercise fads constantly fall in and out of favor. The latest patented fitness system is frequently left to gather dust in the corner as a new machine or routine replaces it. However, some exercise methods withstand the test of time and gain loyal adherents. Pilates, a fitness system developed in the 1920s by Joseph Pilates, has been gaining ground since the 1980s. But what is Pilates and why is it so effective?

 Pilates is a system of exercises that engage the body and mind through a series of controlled movements. These controlled movements incorporate the idea of dynamic tension, or self-resistance. Dynamic tension describes the act of exercising muscle against muscle -- a mode of exercise promoted by the fitness guru Charles Atlas, a contemporary of Joseph Pilates. Pilates employs dynamic tension and allows movements to flow together simultaneously.

Joseph Pilates wanted to increase adherent's flexibility and strength but also realized that a healthy mind and body are interrelated and dependent. Today, the physical trainer's methods have supplanted traditional weight-lifting exercise as an effective way to tone muscle and build strength. 

Why isn't Pilates Trademarked? Pilates' popularity led to new instruction standards and the emergence of a fitness equipment industry. Suddenly, the exercises system's name was everywhere.  In 1992, Sean Gallagher, an equipment retailer and owner of Pilates studios, received trademark registrations for Pilates and Pilates Studio. He began to pursue parties using the Pilates name without certification or permission. But when Gallagher challenged Balanced Body, a manufacturer of Pilates equipment since 1976, a judge ruled that Pilates had lost its trademark significance and hadn't done "anything to prevent others from using their name to describe what they taught" [source: Wilson].

 In this article, we'll learn about Joseph Pilates, the Pilates method and how it became a mainstream and popular exercise system.

Video Gallery: An Exercise Gene?Researchers have found a gene that may be linked to exercise. Learn how this exercise gene allows for people who already exercise to eat fatty diets in this video from ScienCenter.

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