A heavy backpack can cause a manner of musculoskeletal problems in the back so opting for an ergonomic backpack if you normally carry a lot of material to and from work might be a good idea. The true ergonomic backpack will reduce postural distortion and pain, increase stability and safety if you bike to work and reduce the chance of injury. Ergonomic backpacks typically fit closer to the body so if you commute via subway the pack will take up less space and have less chance of contacting those around you.\r