The 15-minute sunlight rule ended my morning energy slump and brain fog — and it can increase energy levels by 20%, doctors say

Woman walking briskly outside.

For over a year now, I've been going for a pre-work stroll every morning to lift my brain fog and boost my energy levels. This morning habit is now an essential part of my day, and I often find myself yawing and feeling groggy whenever I skip it.

But why does a 15-minute morning walk around the block make such a difference to my energy levels? To find out, I asked four doctors why stepping outside after waking up helps me start my day refreshed.