Many people have been told at some point not to cross their legs while sitting, especially at the office or while studying. It is often blamed for causing poor posture, back pain, or circulation problems.

In reality, crossing your legs is not necessarily harmful. The real issue is how long we stay in the same position.

Whether sitting with both feet flat on the floor or with one leg crossed over the other, the human body is not designed to remain still for long periods. Posture is often misunderstood as a single “correct” position that we should maintain all day. In practice, the body functions very differently. Posture is dynamic — it changes as we move.

Our muscles, joints, and circulation systems are built for regular movement and variation, not prolonged stillness. When we remain in the same position for too long, even if the posture appears good, the body begins to accumulate tension and fatigue.

As I often remind my patients:
The body can last a lifetime, if you look after it.

Why We Naturally Cross Our Legs

Crossing the legs is something many people do instinctively. It often feels comfortable and natural, particularly when sitting for extended periods. Crossing the legs helps people shift their weight and relieve pressure from sitting in one position.

This small adjustment serves as the body’s way of redistributing pressure and maintaining comfort.

However, when one leg remains crossed over the other for a prolonged period, the pelvis will begin to tilt and rotate. Over prolonged period of time, the joints of the pelvis can become restricted or “stuck” in that rotated position, something chiropractors commonly refer to as a pelvic subluxation.

When this happens, the muscles around the pelvis and lower back begin to compensate. One side may tighten while the other side becomes overstretched, leading to unilateral muscle tightness and stiffness in the lower back, hip and gluteal muscles.

A similar effect can occur for people sit on one leg, where one foot is tucked underneath their body while seated. This posture also causes the pelvis to tilt and rotate in an uneven way, placing asymmetrical stress on the hips and lower back.

The Key Is Balance

When changing positions after crossing your legs, it is not enough to simply return to a neutral posture. You must change sides.

Alternating sides allows both halves of the pelvis and surrounding muscles to experience the same stretch and tension, helping maintain balance in the body.

For people who have developed an imbalance from years of habitual sitting patterns, switching sides may initially feel awkward or uncomfortable. This sensation is often a sign that the muscles and joints have already adapted to an uneven pattern.

With time, alternating sides can help the body gradually regain balance.

If the awkward or uncomfortable feeling persists despite changing positions, it may indicate that the pelvis has already become subluxated or restricted in that rotated position. In such cases, a chiropractic adjustment may be necessary to restore normal movement in the pelvic joints.

Why Sitting Too Long Causes Discomfort

When it comes to posture, an important factor that many people overlook is circulation.

Even when seated with perfect posture, being in the same position for long periods will reduce normal blood flow to the muscles and surrounding tissues. When we change positions, the contraction and relaxation of our muscles massage the blood vessels to help circulate blood through the area.

As we sit, parts of the body that are pressed against the chair may experience prolonged pressure, which can also temporarily compress blood vessels and nerves.

This is why people often experience sensations such as:

• Pins and needles or tingling in the legs
• Lower back soreness
• Stiffness in the hips
• Tightness in the shoulders or neck

Movement restores circulation and reduces pressure to help relieve the body from discomfort.

A Simple Rule for Sitting

Instead of trying to avoid certain sitting positions completely, focus on avoiding prolonged static posture.

If you enjoy sitting with your legs crossed or sitting on one leg, the key is to switch to the other side every 20 minutes.

These small adjustments help maintain balance in the pelvis and reduce the risk of developing muscle imbalances.

References

• McGill, S. M. (2016). Low Back Disorders: Evidence-Based Prevention and Rehabilitation (3rd ed.). Human Kinetics.
  • Discusses spinal loading, muscle imbalance, and prolonged sitting effects on the lumbar spine.

• O’Sullivan, P., Dankaerts, W., Burnett, A., et al. (2006).
  Effect of different upright sitting postures on spinal-pelvic curvature and trunk muscle activation.
  Spine, 31(19), E707–E712.
  • Demonstrates how pelvic positioning and sitting posture influence spinal alignment and muscle activity.

• Snijders, C. J., Slagter, A. H., van Strik, R., et al. (1995).
  Why leg crossing? The influence of common postures on abdominal muscle activity.
  Spine, 20(18), 1989–1993.
  • Explores biomechanical reasons people cross their legs and how posture affects muscle activity.

• Claus, A. P., Hides, J. A., Moseley, G. L., & Hodges, P. W. (2008).
  Sitting versus standing: Does the intradiscal pressure cause disc degeneration or low back pain?
  Journal of Electromyography and Kinesiology, 18(4), 550–558.

• Pynt, J., Higgs, J., & Mackey, M. (2001).
  Seeking the optimal posture of the seated lumbar spine.
  Physiotherapy Theory and Practice, 17(1), 5–21.