On our Posture page we have seen that we can eliminate the leverages caused by an offset load of a travel day pack or backpack (and the extra forces acting on the body) by aligning the centers of gravity of the load and the body in the vertical axis. A head supported load does this perfectly. If you have ever seen African women carrying loads on their heads you will notice their upright posture and their beautiful graceful gait. If you have developed the spinal support muscles to do this as you grow up this can be a highly energy efficient way to carry a load. This is something you'll want to consider when shopping for women's and men's daypacks for hiking and travel.

The biggest drawback of a head supported load is the inherent instability of the load, making this method of load carrying unsuitable for active movement, rough terrain or high winds. To achieve dynamic movement in all situations we need to lower the center of gravity of the load until it matches the height of the body's own center of gravity, while still keeping the load balanced in front and behind. The body's center of gravity is around the navel area. If we make the center of gravity of the load coincide with the body's own center of gravity, the center of mass of the load can move around your own center in a balanced and fluid way. When we have this ideal weight distribution, we need to incorporate special harness, hipbelt and Balance Pocket systems into our Bodypack to allow these natural body movements. This is how our travel day pack and body pack systems work to create a comfortable, load-carrying system that works with your body to keep you comfortable and retain your range of motion.


Imagine a women's or men's day pack where the shoulder straps and hipbelt move freely with body movement while the pack remains glued to your back. The buildup of fatigue will be reduced and your performance under load will approach the pack-less state. Our patented Flow systems achieve this by linking the harness parts on each side of the pack to each other via sliding or pivoting connections to the pack. This system is part of the reason our hiking and travel day packs are so popular around the world.

Aarn pioneered the development of high stability free movement systems in the late 80s. Since that time the systems have been extended and refined to allow all needed arm, shoulder, hip and torso movements, shown by the arrows below. Some major brands are now beginning to follow our lead, but we're still the best daypack for hiking and travel on the market.

The drawings below show how each Flow system works, the body movement it facilitates and the associated icon. You will find this icon embroidered on the pack to help you identify each system.


The shoulder and hip Flow systems of our hiking and travel day packs are combined differently for small and large packs to achieve the optimum load stability. Twisting of the shoulders relative to your hips is achieved at shoulder level on the daypacks (V Flow, Omni-Flow) and at hip level on the larger packs (Multi -Flow).

Our Flow systems give you an amazing ability to twist, rock, stretch and bend forward under load - to move your body freely and naturally. You can dance with a pack on!

Yet you don’t have to be doing extreme moves to experience the benefits and freedom that Flow brings. Even when walking, you will feel the shoulder straps and hipbelt move with each step, reducing the build-up of fatigue.

Research verifies that our Flow systems enhance balance and make your pack more stable than fixed harness designs. With a naturally balanced load, your safety is maximum in difficult & dangerous country.