Why it’s important to breath during exercise!

Why is breathing so important when exercising? Ok not just regular breathing but the “inhale/exhale” rule.
To maximize your breath you want to exhale on the hard part(concentric phase) and inhale on the easy(eccentric). Exhaling on the hard can also help you get that extra rep in.
So when you workout now you know why? Take those depth breaths, and enjoy your workout!