Wear headband in long running or marathon

Wear a headband while exercise or in a long run because it will observe the sweat and let it fall down in your eyes and face if the sweat come in you eyes then it may irritate you. Second thing you can wear a cap or something like this so that when you suddenly stop in winter or cool environment sudden stopping or slow down will may make a headache or cold because the head will be in direct face or cool air.

Although some player says that they full fill requirement of water during running through sweat they got from there head.