The Muscle Relaxation Effects of Gentle, Focal Load (4.9-7.4 N) With a Narrow Contact Area: A Narrative Review of Kanshoho and Conventional Manual Therapies.

In this narrative review, we summarize the immediate effects of Kanshoho, a novel manual therapy, in the context of chronic musculoskeletal pain. Excessive muscle stiffness is closely linked to chronic pain, highlighting the need for safe and rapid methods to relieve this tension. Kanshoho, a novel low-pressure muscle-relaxation technique developed in Japan in 2007, is characterized by the application of a very gentle, focal load (approximately 4.9-7.4  Newton (N), or ~500-750 gf) to a small area of the body's surface while the patient performs guided active movements. This review summarizes the immediate effects of Kanshoho and identifies optimal application parameters from existing reports, and it compares Kanshoho's outcomes with those of other common manual muscle-relaxation techniques. In patients with chronic nonspecific low back pain, a brief Kanshoho session has been associated with immediate reductions in muscle stiffness and relief of pain. Furthermore, exploratory studies on technique parameters suggest that using a moderately gentle pressure (around 5-7 N) over a narrow contact area (~1-2 cm in diameter) yields the most pronounced muscle-relaxation effect. By contrast, substantially lower or higher pressures, or using a much broader contact area, appear less effective for achieving immediate stiffness reduction. Compared to conventional manual therapies, such as massage, static stretching, proprioceptive neuromuscular facilitation, and myofascial release, Kanshoho produces similar or even greater improvements in muscle relaxation and pain relief, typically in a shorter amount of time and without causing post-treatment soreness. Its non-pharmacological and minimally invasive nature makes it especially suitable for elderly or hypersensitive individuals who might not tolerate more intense interventions. These findings highlight Kanshoho as a promising conservative approach for managing chronic myofascial pain (particularly nonspecific low back pain). However, further well-controlled studies are warranted to confirm its efficacy and to better understand the underlying mechanisms. As a narrative review, no formal statistical synthesis methods were applied.