So i commute everyday.
i have a rear rack on my bike, and for my Long portion of the route i usually strap in my backpack to the rear rack, but there are days when i'm in a hurry, and don't have time to fiddle with the elastic to strap my backpack onto the rack.
So the question is why does it feels like "heavier" or feels like i'm "dragging" something behind, when the backpack is on the rack vs. when it is on my shoulders?
The backpack doesn't wait much, so i can't see that being the issue
the only think i can think of, might just be the wind drag, or perhaps it's just a psychological thing?
my average coast speed is 30 km/h ~ 35 km/h.
and when my backpack is on shoulders i feel the bike going faster, and i use less leg power to maintain the same speed.