Workplace Research: How Seat Cushions Affect Comfort

Ergonomics is a discipline that emerged after World War II. Beyond the styling we commonly associate with it, ergonomics actually covers many other aspects, such as the placement of buttons and the design of instructional text.

In recent years, “ergonomics” has been mentioned frequently across e-commerce platforms and social media, and emerging office chair brands are flourishing. The long periods of isolation, restricted activity, and emotional strain caused by the pandemic have given people a completely new awareness of health. Healthy office work is no longer empty talk.

How can you tell whether an office chair is truly ergonomic?

“Getting injured while sitting in an office” was something our parents' generation found hard to understand, yet today lumbar muscle strain is already very common among young people.

In recent years, Yihang has conducted in-depth research into healthy office work, carrying out a series of studies based at the Yihang-Nanjing Forestry University Healthy Office Research Center.

We found that both consumers and brands concentrate their research on the backrest support points of office chairs, while often overlooking the influence of the seat cushion on sitting posture.

01 Choosing the Right Seat Dimensions: Say Goodbye to Backaches and Numb Legs

Research shows that even when the spine is upright and the body is supported front and back so that forces are shared, prolonged sitting still causes fatigue when the seat height and depth are improperly dimensioned.

So even if we use an “expensive” ergonomic chair, using it incorrectly will still cause discomfort.

Moderate seat height

A comfortable seat height should allow the backrest to support the lumbar spine and maintain its natural curve, while leaving some distance between the popliteal fossa (the back of the knee) and the front edge of the seat to keep blood flowing freely in the legs.

Research has concluded: comfortable seat height = popliteal height + heel height − an appropriate allowance (heel height is generally 25-35mm, with an allowance of 10-20mm).

02 Attention to Cushion Shape: Even Pressure Release

According to the principles of human factors engineering, the most comfortable body pressure distribution should ensure that most of the body's weight is distributed reasonably across the cushion and backrest over a large support area with a low unit pressure.

As the illustration shows, a comfortable seat should conform well to the human buttocks and legs, keeping the ischial tuberosities as the main support points while distributing pressure evenly across the hips and thighs. Even after long periods of sitting, muscles will not feel tense, and the pressure-relief effect is better.

03 Carefully Selected Inner and Outer Materials: Comfortable and Breathable for Long Sits

In an excellent office chair, the seat cushion must contain an elastic layer of appropriate thickness. Because the outermost material is in constant contact with the human body, it should be breathable, wear-resistant, dirt-resistant, and not prone to static build-up with the body or clothing. A non-breathable cushion easily creates an environment favorable to bacteria and germs, increasing the risk of urinary tract infections.

Our research found that compared with traditional cushions, Wintex high-strength mesh fabric offers better support and conformity. As a backrest material, it conforms to the third and fourth lumbar vertebrae and provides elastic support for the lower back; as a seat cushion material, it keeps the cushion breathable with strong load-bearing capacity, delivering a comfortable, airy seat that never feels stuffy.

A Look Back at Yihang's Ergonomic Chairs

#01 Hatu H2

Designed by the Yihang-Nanjing Forestry University Healthy Office Research Center, the Hatu H2 was launched after three years of analyzing data from nearly 4,000 samples, based on insights into the healthy workplace seating needs of Fortune 500 companies such as Walmart. The Hatu H2 introduces the physiological concept of “bridge yoga,” applying healthy research based on the body's curvature to provide zoned support for the cervical, thoracic, and lumbar spine, decomposing pressure and scientifically protecting the spine.

The seat cushion is filled with 60mm of high-density molded foam—no rigid bottoming-out, just a soft embrace. Breathable mesh provides 3D circulating heat dissipation for a refreshed feeling at all times.

With 10-step, stepless 56mm height adjustment, it can be precisely positioned for different heights and postures, supporting the fatigue-prone 4th-5th lumbar curve anytime, anywhere. It gives the lumbar spine customized care and the feeling of “yoga at your workstation.” With human-machine fit and sensory enjoyment, the Hatu H2 delivers the ultimate healthy sitting experience.

#02 H'up

Medical research has found that shoulder, neck, and lower back pain is caused chiefly by excessive spinal load—spinal pressure becomes too great, and compensating shoulder, neck, and back muscles lead to pain and injury.

When you sit down, the chair back is the only barrier. Because our heights and spinal lengths differ, one-size-fits-all office chairs often cannot meet the needs of people of different heights. Based on this insight, H'up was created: a chair that extends and adjusts along with your spine.

The H'up was designed by the Italian studio CLAUDIO BELLINI DESIGN. Its unique look and full-frame structure deliver a striking visual artistic impact.

The Wintex all-mesh breathable seat cushion from the Korean brand offers strong load-bearing capacity, a comfortable seat, and excellent breathability without stuffiness, overcoming the poor ventilation of traditional chairs. The ergonomic backrest rises and falls independently by 50mm, following your spine to customize your personal chair.

#03 Winger

The designers drew inspiration from the outstretched wings of a swan, incorporating the swan's wing-spreading posture into the chair's lumbar support design and infusing the office space with an air of elegance. The waterfall-style cushion has smooth, flowing lines that drape naturally without pressing into the legs, while molded foam supports the hips and thighs for more thorough pressure relief.

The Winger office chair is designed to keep users comfortable and healthy. With comprehensive ergonomic support and a rich set of adjustment functions, it helps users effectively release pressure on the head, neck, and lower back, giving everyone a healthy chair that suits them.

Yihang-Nanjing Forestry University Healthy Office Research Center

The Yihang-Nanjing Forestry University Healthy Office Research Center was jointly established by Yihang Technology Co., Ltd. and Nanjing Forestry University. Combining Yihang's positioning in office furniture, it conducts research into the ergonomic characteristics and health topics of furniture products, office behaviors, and office environments, with the aim of building a safe, healthy, comfortable, and efficient healthy-office system.