Most people picture barbells, reps, and progressive overload when they think about getting stronger. But what if strength could sometimes be unlocked not by adding load, but by freeing a joint? A capstone project by Dr. Peter Calicchia and fellow members of the New York Medical College Doctor of Physical Therapy Class of 2025 set out to systematically review exactly that question.
What a joint mobilization actually is
Joint mobilizations are passive, skilled manual therapy techniques applying graded movement to a joint, influencing the soft tissue around it. They span a spectrum of technique:
- Maitland mobilizations (Grades I-V): rhythmic oscillations for pain modulation and joint mobility
- Kaltenborn techniques: sustained glides for joint traction and capsular stretch
- HVLA thrusts: quick manipulations at end range to restore joint mechanics
- Mulligan's Mobilization with Movement: therapist-applied glides combined with active, pain-free patient movement
These are not just "cracks" or "wiggles." Applied with clinical reasoning, they create measurable neurophysiological and mechanical changes that can unlock underperforming muscle groups.
Two mechanisms behind the effect
Arthrokinetic Reflex (AKR). A spinal-level reflex first explored in the 1950s: mobilizing a joint stimulates mechanoreceptors and triggers reflexive contraction of the surrounding muscles (Makofsky et al., 2007), increasing motor unit recruitment, and reducing inhibitory signals from the brain. In practical terms, a hypomobile joint often neurologically inhibits its local muscles, and mobilizing it restores normal input and increases firing.
Mechanical efficiency. Poor joint mechanics mean poor leverage. Restoring normal joint motion improves the length-tension relationship of the surrounding muscles, letting them contract from a mechanically advantageous position and improving torque output.
The honest caveat
Protocols across the 13 studies varied enough that definitive clinical guidelines are not possible yet. There is also real subjectivity in technique: what one clinician calls a Grade III mobilization, another might not, which affects reliability. The takeaway is not "any mobilization works for anything." It is that joint mobilization deserves a real place in a clinician's toolkit, applied individually based on the joint, the presentation, and the clinician's own experience with the technique, while research works toward more standardized protocols.
References
Al Khawajah & Alshami, 2019, BMC Musculoskeletal Disorders. Chesterton et al., 2021, J. Manipulative & Physiological Therapeutics. Ersoy et al., 2019, J. Sport Rehabilitation. Ghan & Babu, 2021, J. Manual and Manipulative Therapy. Lucado et al., 2019, J. Hand Therapy. Makofsky et al., 2007, J. Manual and Manipulative Therapy. Pfluegler et al., 2020 & 2021, Musculoskeletal Science and Practice / J. Manual & Manipulative Therapy. Silva Neto et al., 2019, Musculoskeletal Science and Practice. Tomruk et al., 2020, J. Sport Rehabilitation. Wong et al., 2020, J. Sport Rehabilitation. Yin et al., 2022, Int'l J. Environmental Research and Public Health.