Office Chair Backrest Adjustment

The adjustment methods and precautions for the adjustable backrest of an office chair are as follows:

I. Basic Adjustment Methods

1. Angle Adjustment: The adjustment handle of most office chairs is located on the right side of the seat. To operate, first sit on the chair, pull the handle, lean back slightly with your back, and release the handle to fix the angle. To return to the original position, continue pulling the handle and apply slight force, and the backrest will automatically spring back. Some high-end models (such as DOWINX) support infinite adjustment from 90° to 170°. By loosening the black cylinder at the bottom, you can activate the "rocking mode" to enable back-and-forth rocking.
2. Reclining Function: To fully recline the backrest, find the dedicated lever below the right armrest. Pull it and lean back with your body to achieve a position close to lying flat.
3. Rocking Amplitude Adjustment: By rotating the black cylinder (usually thicker) in front of the chair's gas cylinder, you can control the amplitude of the back-and-forth rocking. Rotating it clockwise or counterclockwise can increase or decrease the range of motion.

II. Angle Selection and Health Recommendations According to usage scenarios and ergonomic principles, different reclining angles serve specific functions:

• 90° Upright Position: Suitable for focused office work. At this angle, your body and thighs form a right angle, effectively dispersing lumbar pressure and protecting the health of your cervical and lumbar spine.
• 100° Slightly Reclined Position: Ideal for surfing the internet, watching movies, or playing casual games. This angle reduces the vertical distance between your eyes and the screen, relieving eye strain while maintaining slight support for your waist.
• 125° Semi-Reclined Position: Perfect for short naps. Your body weight is evenly distributed, reducing the burden on your spine. However, ensure proper head support to avoid your neck hanging in the air.
• 155° Nearly Flat Position: Only recommended for deep sleep or extreme fatigue. Long-term use may cause excessive lumbar curvature and increase the risk of muscle strain.

III. Adjustment Details and Health Tips

1. Seat Depth Adjustment: Adjust the seat cushion so that your thighs are fully supported and there is a two-finger gap behind your knees to prevent restricted blood circulation in your legs.
2. Lumbar Support Positioning: Ensure that the lumbar support is aligned with the third lumbar vertebra (approximately the most prominent part of your waist). When reclining, keep your pelvis slightly tilted forward, with your thighs at a 95° angle to the horizontal plane. This posture minimizes lumbar pressure and relaxes your gluteal muscles.
3. Dynamic Usage: Avoid staying in the same angle for a long time. It is recommended to slightly adjust the backrest angle or get up and move around every 30 minutes to promote blood circulation.

IV. Special Function Explanation Some office chairs are equipped with a "synchronized tilting" function, where the backrest and seat cushion adjust in tandem. In this case, you need to control the overall tilting amplitude using the knob or lever below the seat. Refer to the specific model's instruction manual for operation.