I swore off backpacks back when I was a stupid teenager. A friend and me decided on the spur of the moment to cycle 75 miles to see his grandfather. We packed everything for a week of camping in our framed backpacks. This was back in the 1970's, long before the word ergonomic was invented. 12 hours later, we struggled up the road to my friend's grandfathers house on foot because my back could not take it anymore. The next day, we called my parents to come and pick us up. I could barely walk and I could not get on the bike. I never put anything on my back when cycling ever since. We were stupid, so stupid we did not even have a way to fix a flat. We didn't have a flat.

I use a Timbuk2 Hunchback Rack Trunk. It holds lunch, tools, inner tubes, pump and winter gloves (sometimes needed in summer). Sometimes, I stop at a grocery store, on the way home from work and I can still fit more stuff in the trunk. My back has reciprocated my good care by not giving me any problems or pain.