On our first hunt, the first morning, we were walking up a logging road with our bows on our packs. We were just be-bopping along and then my buddy was like "Reckon Ill rip a bugle". He called, we waited, and then we just started easing back up the road. Less than a minute passed and we heard something. We looked up and my buddy saw the antlers coming through the trees and I saw the body. He was at 35-ish yards broadside staring at us. All 3 of us had our bows on our packs....... That bull stared until I hate the great idea to hit the ground and try and get my bow off my pack. He was gone before I even cleared the buckle.
We learned that if the sun is out, we either have our bow in hand, or we balance it on the pack like some have said here.
The way I prepare for this is by walking with either dumbells or kettlebells will walking around the house with my pack.