I just did ~4 miles with my sling bag — a quick walk around the block. I had to pick up some meds for my dog at the vet and rather than drive, I took the bag and walked there and back. My cell phone was in the bag and when needed I slid the bag around so it was on the chest and looking down at both zippers. Same when I picked up the meds, slid the pack around, opened the zipper, placed the meds in and closed it. When opened in the chest position, both zippers face up so nothing falls out. Nice bag for carrying light stuff around the block.