ZACKBACK® Posture Chair
for the Computer, Microscope & Microtome


"I'm not even sure it should be called a 'chair.' There are chairs, and then there is the ZACKBACK. The two have very little design details in common; the ZACKBACK actually enhances your ability to work while seated.

The thought of doing without the ZACKBACK - of going back to ordinary chairs - is horrifying. Fortunately for me, that's not going to ever happen.

I've bought a lot of chairs that claim to be ergonomically designed. The ZACKBACK makes those fallacious claims laughable. This chair is far and away the best."

-Terry Goodkind
New York Times
Bestselling Author


"After a day or so of getting used to your 'sitting system' (it's a lot more than just a chair!), a ton of chronic pain vanished from my body. It's a far bigger improvement than I thought possible in my wildest dreams.

Thanks and thanks also for the superb customer support. I wish you all the luck in the world in getting your message to more people. What you say is true: How you sit makes a huge difference in how you feel..."

-Ken McCarthy
Internet Pioneer, Speaker, and Author

Click here for more reviews of the most acclaimed chair for relieving pain and improving posture.   Microscope and Microtome users click here for your healthiest posture.


Want to Enhance Your Workday Performance?

...Then optimize your workday posture, breathing, & core stability with ZACKBACK!

Here's why ZACKBACK's Core Posture is your B.E.S.T. Posture.

Breathing: The unique lower thoracic support (figure 1) of the ZACKBACK chair immediately promotes proper diaphragmatic breathing (figure 2). Leaning against other so-called ergonomic backrests restricts diaphragmatic breathing and promotes unhealthy upper chest breathing. This results in overuse of the scalene muscles, a major cause of neck pain, referred arm pain, thoracic outlet syndrome, and fatigue (figures 3 and 4).

ZACKBACK’s lower thoracic support dramatically improves diaphragmatic breathing for 2 reasons:
(1) Mechanical support to the lower thoracic spine elevates the rib cage and prevents its downward movement. This mechanical support immediately reduces the static load on the scalene muscles.
(2) The isolated firm pressure stimulation to the lower thoracic region of the back elicits certain reflexes (called the intercostal-to-phrenic reflexes) that activate the diaphragm.

Elongation: The unique, multi-adjustable, dual back support system of the ZACKBACK chair elongates (lengthens) your spine for healthy, elegant posture. (See figure 1.) Chairs with lumbar support shorten and distort your spine! (See figure 5.) Elongation gives a feeling of weightlessness to your lower back when sitting. Lumbar support gives a feeling of compression to your lower back when sitting.

Stability: ZACKBACK’s sacral support stabilizes the pelvis in its proper neutral position and ZACKBACK’s lower thoracic support elevates and stabilizes the rib cage. (See figure 1.). As a result, a slumped sitting posture and its associated health risks are prevented. These two critical areas requiring isolated stabilization (the pelvis and the rib cage) are ignored by proponents of lumbar support and reclining backrests. In addition, breathing in the ZACKBACK chair results in a co-activation of the diaphragm and deep lower abdominals (transversus abdominis) - the key to enhancing core stability.

Tone: The distorted sitting postures in other chair designs (reclining backrests, lumbar supports) relax the lower abdominals (including the important transversus abdominis), resulting in a protruding lower abdomen. (See figure 3.) By promoting proper activation of the transversus abdominis, the ZACKBACK chair increases your lower abdominal muscle tone as you sit, resulting in a taut lower abdominal wall! (See figures 1 and 2.)

Figure 1.
ZACKBACK's dual back support system
Figure 2.
ZACKBACK Sitting involves a raised position of the diaphragm. Note in particular the greater depth and expansion of the lower rib cage.
Figure 3.
When leaning against other backrests, there is a relaxation of the abdominal muscles and a lowered position of the diaphragm. Diaphragmatic breathing will be restricted and upper chest breathing will be emphasized.
Figure 4.
Upper chest breathing results in overuse of the scalene muscles to elevate the upper two ribs against gravity.

Figure 5.
Sitting with lumbar support. Note the unhealthy backwards displacement of the upper trunk, and the overstretching of the abdominal muscles.
Lumbar support shortens, compresses, and distorts the spine.




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