get a rear rack, and strap your backpack there when you ride.
that is what i do, for my long sections of my trip.
for short ones i keep the backpack on my back.
As mentioned already by others, having a backpack can have some effect to some degree or another.
but most importantly, is how you Sit and ride on your bike.
Originally Posted by
gholt
I ride about 2,500 to 3,500 miles a year to work and back, and most of the time I wear a backpack. Sometimes it is heavy and sometimes it is not. I try to fit most of the stuff on my rear bikerack. My trip to work and back is probably about 2 1/2 hrs. round trip. Sometimes when I get to work in the morning my back feels a little sore. Most of the time it is not sore, but I stretch it out when I get to work every day.
It seems every year around this time I have to go into the chiropractor and have my lower back adjusted. It seems it gets a little twisted. I asked the chirpractor if wearing the backpack would twist it and he did not think so, because I ride so much. the injury is not something that has to be built up to it. So, I thought I would ask all those experienced riders out there. what they think.