The Ultrabreathe is a highly effective inspiratory muscle trainer, providing an easy and convenient means of increasing the strength and durability of the respiratory muscles.
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It works on the principle of resistance. As you inhale, the resistance created makes your respiratory muscles work harder, and the harder they work the stronger and more durable they become - and as your breathing power improves, the Ultrabreathe can be gradually adjusted to provide more resistance.
It's weight training for your breathing muscles!