The stretch program is a pretty standard auto program on most chairs nowadays. However, it can be quite different, depending on the roller track configuration. The “idea” of the stretch program is the same for both L-track and S-track chairs, but the application is different because of the physics of construction.
The most common type of S-track stretch is a “global” stretch that involves 2 primary components: 1.) the chair back reclines and, 2.) the calf & foot airbags inflate while ottoman drops down. The idea is for the gravity to pull the body downwards when the chair back reclines, providing traction so that when the calf and foot airbags inflate and the ottoman drops, the pull on the legs will pull and elongate the whole spine. It really is a very good experience for most users. As a matter of fact, it would not be hyperbole to say that users “love” the global back stretch of these massage chairs. In some chairs, shoulder airbags are also used. They inflate when the chair back reclines, thus pinning the shoulders back and further tractioning the spine when the ottoman drops down.
The chair that we have found to have the most pronounced axial/global stretch of the S-track chairs is the Infinity IT-8500/8500X3. They use the shoulder and calf/foot airbags, along with a 180 degree chair back recline (closer to horizontal than any other S-track chair), to really give a good stretch for the user. Again, most, if not all, S-track chairs have a stretch program of some sort, but this type that I’ve just described is the most common and sought after.
Some S-track chairs, like the Panasonic MA73 and the Osaki Japan Premium 4.0 models, use segmental stretching instead of full body extension, as described above. For example, the MA73 has 3 different stretch programs: a neck stretch, a back stretch, and a hip stretch. It doesn’t use the “global” stretch approach of the more common stretch programs that we have been discussing.
L-track chairs, for the most part, also have a stretch program but because of the shape of the roller track, the stretch component is a little limited. Here’s why:
The advantage of the S-track chairs, when it comes to the stretch program, is that the chair back moves independently of the seat. The seat remains relatively horizontal while the chair back reclines to approximately horizontal. That, in combination with the ottoman dropping down, is what really creates the magic of the stretch program.
The physics and build of the L-track won’t allow for the horizontal chair positioning that the S-track chairs enjoy. The seat and chair back articulation is fixed in an “L” shape position. You just can’t flatten out a steel roller track that is shaped in an L position. So, instead of having a stretch program that flattens the body to a horizontal position, the L-track stretch programs involve reclining the chair into a zero gravity-like position and the deploying the calf and foot airbags while the ottoman extends (lengthens) and then drops down. The effect on the user is that you will feel the pulling of your legs and a pull on your hips, but the overall global stretch experience will not be felt, because it quite simply can’t be done. I hope that made sense. I’ve included a video below to try to show the difference in body position in both a reclined S-track chair and a reclined L-track chair.
The trade off with these two types of chairs is the L-track roller experience vs. the S-track stretch experience. You have to determine which is most important to you when making the chair buying decision.
Dr. Alan Weidner
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