Mobility is frequently treated as a separate discipline from strength training — something done at the end of a session as an afterthought, or reserved for a dedicated class once a week. This separation misrepresents what mobility actually is and what limits it.
Range of motion under load is a strength quality. The capacity to move through a full range of motion in a squat, hip hinge, or overhead press depends not just on tissue length but on the ability to produce and control force throughout that range. Mobility training, in this sense, is not passive — it is a form of progressive loading that develops the muscular and neural capacity to own a range of motion rather than simply pass through it.
Two types of limitation
When a joint won't move through its full range, the limitation is usually one of two things — and they require different approaches.
Structural limitations arise from the bony architecture of the joint itself. Hip sockets vary significantly in their depth, orientation, and angle between individuals. Some people will never achieve a deep squat with a narrow stance because their femur meets the acetabulum before that position is achievable — this is a structural reality, not a failure of mobility. Attempting to force range of motion past structural limits risks joint damage rather than improved mobility.
Muscular and neurological limitations are different. Tightness that results from shortened muscle tissue, elevated resting tone, or neurological protection responses is addressable through training. The body restricts range of motion in unfamiliar positions partly as a protective mechanism — the nervous system is reluctant to allow movement into positions it doesn't have the strength to control. Training that develops strength in lengthened positions progressively reassures the system and allows range to expand.
Distinguishing between these two limitation types is the first practical step. Structural limitations require programme modifications — a wider squat stance, a raised heel, a different exercise selection. Muscular and neurological limitations respond to training.
Why passive stretching has a ceiling
Passive stretching — lying in a stretched position and waiting — develops tolerance to stretch and modestly increases range of motion over time. But it does not develop the muscular capacity to control that range under load. A person who can passively achieve a deep hip flexion position in a stretch may still lack the strength to hold that position under any significant load.
Research supports this: strength training through a full range of motion improves flexibility comparably to static stretching, while also developing the muscular capacity that makes that range useful. The two are not opposed — but loaded mobility work is more transferable to training outcomes than passive stretching alone.
What ATG training addresses
The ATG (Ass To Grass) training approach, developed around the work of Ben Patrick, specifically targets the mobility floor through progressive loaded range-of-motion work. Exercises like the ATG split squat, the Nordic hamstring curl, and the tibialis raise are designed to develop strength in ranges that conventional training tends to avoid — the deep knee flexion, extreme hip flexion, and ankle dorsiflexion positions that compound lifts require but rarely fully train.
The principle is the same as progressive overload applied to range: start within your current comfortable range, and gradually extend it under control. Over weeks and months, range of motion under load improves as the muscular capacity in those positions develops.
Intentra's mobility blocks within strength sessions are built around this principle — developing range and strength together, rather than treating mobility as a separate discipline.