BackTpack Concept

Gravity is the ultimate organizer of human posture. When we align ourselves with gravity, everything benefits.

Natural posture is the body’s most efficient response to gravity. Everything that is carried above our feet is our body's load — our head on top and all of our organs and body parts blow it. They are organized around the spinal axis. Everything below the head directs the head to its tallest place on the vertical spinal axis. All of the dynamic systems of the body participate in this directional mission.

How to carry a bag with natural, healthy posture

The combination of our body's center of gravity plus the center of gravity of the weight we are carrying, creates a new center of gravity. When what we carry is on top of our head, its center of gravity aligns vertically with ours. When what we carry is spread equally to the left-and-right of our body, or to the front-and-back of our body, the resulting forces align with our center of gravity.

When we stand on our feet, our center of gravity must be over our feet or we will fall over. When we carry a load, our center of gravity includes the applied load. Our center of gravity shifts if the load is off of the vertical axis of your spine.

If the weight we carry is off-axis (in front, to one side, or behind), our center of gravity shifts, causing us to lean away from the load to keep our new center of gravity over our feet so that we don't fall. With an off-axis load, our posture distorts to accommodate the bag's weight. The heavier the load, or the further away the load is positioned from the center of the body, the more we lean and distort our posture.

Line Drawing of Posture

Reducing forces on the spine when carrying a load

The force applied to support the load must go through the center of gravity of the load. So again, when the load is balanced, or on our head, the supporting force is simply equal to the weight we carry, and in the opposite direction: straight up!

When the weight is off-axis, we must pull in a direction such that the direction of the pull goes through the center of gravity of the load. This introduces a horizontal component to the force, which is added to the weight, meaning that more force is required. Put another way, a heavy backpack requires you to lean forward and pull forward with your shoulders. This is why you see hunched shoulders and forward heads with backpack use. With the same load in a BackTpack, you eliminate the forward pull.

It is also the reason that people say, "The load feels lighter!" when they try on a BackTpack loaded with the contents of their conventional backpack.

Training postural efficiency with axial-loading

These systems require resistance and use to stay strong. Loads applied to the body’s vertical spinal axis enhance and strengthen this efficient posture and organization of movement. However, when off-axis forces are applied, the body’s postural system must accommodate, creating distortion of this perfect organization. Thus more energy is expended as additional forces are applied.

The only way to apply a load directly to the entire vertical spinal axis is to place it on the head. However, balancing the load front-back or side-side places the resulting force on the vertical axis as well.

Keeping the focus beyond vertical

The purest demonstration of natural posture is seen in toddlers who have just learned how to balance their head on top of their body and walk, their ultimate goal. As we go past our toddler years we encounter many physical and emotional demands throughout life which distract us from this focus and bring us down. Keeping the vertical focus is uplifting in many ways, but especially for maintaining the body’s efficiency and ease of movement with our tallest posture as its foundation.

The more we embrace this concept the more we will adopt habits to preserve and strengthen our natural posture throughout our lifespan.

Our carrying products train natural posture

BackTpack's mission is to provide products that train fullest movement potential throughout the lifespan by enhancing optimal posture; the foundation of this potential. Optimal posture is the body's response to load on the vertical axis. Our products are designed to apply loads to the vertical spinal axis in daily activity to train the habit of optimal posture.

Both the BackTpack and our Tumpline Trainer align the human system with gravity through axial-loading to train fullest posture. Fullest posture allows the musculoskeletal system to work naturally and efficiently with gravity. It also provides the postural space internal mechanisms need for unimpeded optimal function.


Backpack and BackTpack comparison showing why BackTpack works

Backpack distorts posture (left). BackTpack trains good posture (right).

Tumpline Trainerused with a backpack

Tumpline Trainer
used with a backpack

Unlike backpacks or messenger bags, BackTpack, with its balanced side bags, applies the load to the body’s vertical axis, thereby eliminating posture distortion and decreasing the effort required to carry the load, in obedience to the laws of physics. The load feels lighter and you stand straighter.

The structures of the head and neck have one purpose and that is to keep that heavy head as high and centered as possible for ease of movement with minimal force. The Tumpline Trainer builds on that directional purpose. The  Tumpline Trainer provides awareness and a feeling of axial lengthening and strengthening for ease and efficiency.

BackTpack and the Tumpline Trainer were created to train natural posture with axial-loading in daily activity, not only to become a habit, but to eliminate pain and the burdens of distortion that reduce joy in activity.