An anatomically segmented backpack has an upper back region, a lower back region, and a hip belt region. The upper back region includes a shoulder strap joined to a pack load carrying portion and a thorax harness. The thorax harness extends in two opposite directions under each shoulder blade of the user. The lower back region is coupled to the upper back region and a hip region. A slide mechanism is located in the pack load carrying portion of the upper and lower back region. A load-bearing element is disposed within the lower back region, for transferring a load from the upper back region to the user's hips. The hip region is joined to a front section of the pack by a load bearing hip belt that extends around the user.