Bas Rutten O2 Trainer

You’ve got a day for arms, legs, and every other external body part, but have you ever spent any time working your lungs at the gym? The O2 Trainer promises to give you bigger, stronger, and faster lungs through the power of resistance via one simple mouthpiece.

Designed to train your lungs and body to perform at a higher level by using less oxygen and increasing your lung volume, the O2 Trainer can be used during just about any exercise, from running to power lifting. The way you use it is by adjusting the level of restricted airflow as you gain endurance; so you start with “end cap number 1,” which has a hole of 13mm, and as your lungs adapt, you decrease the size of the insert and go to “end cap number 2”, etc. The end result promises to be a strengthened diaphragm, core, and chest muscles. [Purchase]