The Evolution Chair is specifically designed without a backrest to provide optimum health benefits. The  absence of a backrest allows for full activation of your deep core muscles. When you sit on an Evolution Chair, your body balances and adjusts to the bounce, sway, and tilt of the ball, which engages your core and builds the endurance and strength of your postural muscles. The presence of a backrest impedes this process, compromising the health benefits of active sitting.

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