Cleats or spikes on shoes make friction because they provide a surface.

Explanation:

Cleats or spikes on shoes make _more_ friction because they provide a _rough_ surface.

they deliver oxygen to the blood

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.