The simple answer to whether your feet should touch the ground when sitting is a definitive yes, or they should at least be fully supported on a stable surface. Proper foot support is a foundational requirement for maintaining a healthy seated posture and minimizing strain on the musculoskeletal system. When feet are left dangling or unsupported, the entire alignment of the body is compromised, creating a chain reaction that can lead to discomfort and long-term issues.
The Foundation of Proper Seating Alignment
The goal of ergonomic seating is to achieve a balanced, neutral posture that minimizes stress on the joints and spine. This ideal is often described by the 90-90-90 rule, where the ankles, knees, and hips are positioned at roughly a 90-degree angle. The feet must be flat on the ground or a footrest to establish this foundational alignment.
When the feet do not have solid contact with the floor, the weight of the lower legs pulls downward, causing the pelvis to tilt backward. This posterior pelvic tilt flattens the natural inward curve of the lower back (lumbar lordosis). Flattening this curve places pressure on the spinal discs and ligaments, forcing back muscles to work harder to maintain an upright position.
The lack of a stable base means the hips are not properly supported, disrupting the balanced distribution of body weight across the thighs and buttocks. This unbalanced position forces the body to compensate, increasing strain on the lower back and sacrum. Correct foot placement ensures the pelvis remains in a neutral position, which supports the spine’s natural S-shape.
Circulation and Postural Consequences of Unsupported Feet
Beyond biomechanical alignment, unsupported feet negatively impact circulation and overall posture. If a chair is too high, the edge of the seat can press into the underside of the thighs, particularly behind the knee. This pressure compresses blood vessels and nerves, restricting blood flow to the lower legs and feet.
This compression reduces venous return, which may lead to symptoms like tingling, numbness, or the sensation of legs “falling asleep.” Over time, this chronic pressure can contribute to circulatory issues such as swelling in the ankles and feet. The lack of grounded foot support also forces the body into awkward compensatory postures.
A person whose feet are dangling may subconsciously slouch forward or lean heavily on armrests to find stability. This leaning transfers strain to the neck, shoulders, and upper back, often resulting in muscle tension and pain. Full, flat foot contact provides the necessary counter-force to stabilize the lower body, allowing the trunk and neck muscles to remain relaxed.
Practical Steps for Achieving Optimal Foot Placement
Achieving the correct foot position requires careful adjustment of the chair and the workspace. The first step is to adjust the seat height so the feet rest flat on the floor while the knees are level with or slightly below the hips. If the chair is adjustable, this modification is the most direct solution to ensure proper lower body geometry.
However, many users must raise their chair height to position their elbows correctly for typing on a fixed-height desk. In this scenario, the feet will no longer touch the floor, making a footrest a necessary piece of equipment. A good footrest should have an adjustable height and angle to accommodate individual needs, allowing the user to maintain the 90-degree knee bend.
The footrest should be positioned directly beneath the feet, ensuring the soles are fully supported, not just the toes.
Seat Depth Check
When setting up the chair, a simple self-check involves fitting two fingers between the back of the knee and the front edge of the seat pan. If there is less space than this, the seat is too deep. A seat that is too deep can cause pressure on the back of the thigh and hinder proper foot placement.