Controlled Articular Rotations (CARS) are an active mobility training system designed to improve and maintain the health of your joints. Unlike static stretching, which focuses on lengthening muscles, CARS involve actively moving a joint through its maximum available range of motion. The system emphasizes intentional control over the movement, which distinguishes it from passive movements. This practice is a method for the nervous system to regularly map and reinforce the usable space around each joint.
Defining Controlled Articular Rotations
Controlled Articular Rotations are active, rotational movements performed at the outer limits of a joint’s motion. The goal is to articulate a joint through the largest circular path possible without pain or allowing movement from neighboring joints. This active control converts passive flexibility into usable, functional mobility.
The practice requires three key components:
- Active control: The joint is moved entirely by the surrounding muscles, not by momentum or external force.
- Maximal circle: Constant effort is applied to expand the circumference of the rotation, actively exploring the joint’s current limits in all directions.
- Joint isolation: The rest of the body is braced to ensure the movement truly comes from the target joint and not from compensatory movements in the spine or pelvis.
The Physiological Role in Joint Health
CARS practice is directly linked to the biological needs of joint tissues, particularly the cartilage. Joints are nourished by movement because cartilage is avascular, meaning it lacks a direct blood supply. Actively moving the joint through its full range acts like a pump, driving synovial fluid—the joint’s natural lubricant—into the cartilage. This lubrication reduces friction and provides necessary nutrients to the joint surfaces, supporting joint longevity. The consistent, controlled loading at the end ranges also signals the joint capsule to maintain or potentially increase that range.
The exercises also provide extensive neurological input, reinforcing the brain’s map of the joint’s available space, a process known as proprioception. Sending signals from the muscles and mechanoreceptors in the joint capsule helps the central nervous system regain control and stability at the outer limits of motion. When a range of motion is not regularly used, the nervous system may restrict access to that space as a protective mechanism. CARS systematically teaches the nervous system that the maintained range is safe and usable, improving joint stability and kinaesthetic awareness.
Essential Technique for Effective CARS
To ensure a CAR is effective and truly isolates the intended joint, the principle of “irradiation” is employed. Irradiation involves generating full-body tension by bracing muscles throughout the core, limbs, and non-moving joints. This bracing stabilizes the body, preventing compensatory movement that would otherwise mask a true lack of range in the target joint.
The movement must be slow and deliberate, typically taking between 10 and 20 seconds to complete a full circle. A slow tempo ensures the muscles actively control the joint through every millimetre of the rotation, rather than relying on momentum. Moving slowly also allows the user to maintain a consistent level of tension, which is self-selected based on the desired training effect.
CARS also serve as a daily diagnostic tool for the body’s current joint capacity. If the movement feels restricted or causes pain, especially “closing angle” pain where joint surfaces compress, it provides immediate feedback that the nervous system is protecting that range. This allows the user to adjust the circle to a pain-free range, respecting the body’s current boundaries. These controlled movements are often performed daily as part of a mobility routine or as a specific warm-up before intense training.