Introduction

For many people living with lower back pain caused by a disc issue, the discomfort doesn’t go away when they rest — it can actually get worse. If you’ve ever found yourself waking up with a stiffer, sorer back than when you went to sleep, you’re not imagining things. This paradox is frustrating, but physical therapists have a clear understanding of why it happens and, more importantly, what you can do to relieve it.

What Happens When You Lie Down?

The spine is a complex structure of bones, discs, muscles, and nerves that work together to support movement and absorb shock. When you lie down — particularly on your back or curled into a fetal position — the distribution of pressure changes along your spinal column.

“If you have a bulging or herniated disc, gravity can cause the disc to press more directly on the surrounding nerve roots when the supporting musculature is relaxed,” says Dr. Amanda Liu, PT, DPT, a licensed physical therapist in Chicago. “This can result in an increase in pain, numbness, or tingling — especially during prolonged rest.”

The intervertebral discs themselves are particularly sensitive to compression. Studies show that spinal disc pressure is actually lowest when lying flat on the back with the knees elevated, but positions that flex the lumbar spine — such as curling on your side or slouching — can increase disc bulge and aggravate the issue1.

The Role of Muscle Imbalances and Poor Sleep Posture

Another key contributor to nighttime pain is muscular imbalance. “When you’re upright, your core, glutes, and back muscles provide constant support to the spine,” explains Liu. “At night, those muscles relax, and if your mattress or pillow doesn’t promote good alignment, the spine can sag or twist out of position.”

Poor posture during sleep, such as sleeping with the pelvis tilted or using an unsupportive mattress, may increase the strain on the lumbar region. Tight hamstrings and hip flexors can also pull on the pelvis, altering spinal alignment and intensifying pain2.

What Physical Therapists Recommend

Here are evidence-based strategies that physical therapists often recommend to manage lower back disc pain during rest:

1. Optimize Your Sleeping Position

  • Back sleepers should place a pillow under their knees to reduce lumbar lordosis and ease disc pressure.
  • Side sleepers should sleep with a pillow between their knees and draw their knees slightly toward the chest to keep the spine neutral.
  • Avoid sleeping on your stomach, which hyperextends the spine and can worsen disc pressure3.

2. Gentle Core Stabilization

Physical therapists encourage low-impact core engagement exercises to stabilize the lumbar region. Start with:

  • Pelvic tilts: Lie on your back and gently rock your pelvis to flatten and arch your lower back.
  • Abdominal bracing: While lying on your back, tighten your abdominal muscles without holding your breath to create a supportive corset effect around the spine4.

3. Incorporate Mobility and Flexibility Routines

Daily stretching of the hamstrings, hip flexors, and lumbar spine can relieve tension and promote healthier alignment.

Try:

  • Child’s pose to cobra sequence to mobilize the spine safely.
  • Standing hamstring stretches to reduce posterior chain tightness.

4. Check Your Sleep Surface

An unsupportive mattress may undermine all your efforts. Research suggests that medium-firm mattresses are most effective for reducing chronic lower back pain5. Consider using a lumbar support pillow or a mattress topper that promotes spinal alignment.

When to Seek Professional Help

If your pain includes radiating leg symptoms, numbness, or weakness, or you have any bladder or bowel dysfunction, it’s important to consult a healthcare provider immediately. These may be signs of more serious nerve involvement.

A licensed physical therapist can conduct a full evaluation and develop a customized program to address your disc-related back pain — often including manual therapy, targeted exercise, and postural education.

Conclusion

While it may seem counterintuitive, lying down can increase lower back pain due to changes in disc pressure, muscle relaxation, and poor sleep positioning. Fortunately, with the right combination of postural adjustments, core work, and sleep surface improvements, you can wake up with less pain — not more.

Footnotes

  1. Nachemson, A. “The Load on Lumbar Discs in Different Positions of the Body.” Clinical Orthopaedics and Related Research, vol. 45, 1966, pp. 107–122. ↩
  2. McGill, Stuart. Low Back Disorders: Evidence-Based Prevention and Rehabilitation. Human Kinetics, 2015. ↩
  3. Rothstein, Jay M., and Roy A. Skelly. The Spine: Physical Therapy Management. Mosby, 2005. ↩
  4. Kisner, Carolyn, and Lynn Allen Colby. Therapeutic Exercise: Foundations and Techniques. F.A. Davis Company, 2017. ↩
  5. Jacobson, BH, et al. “Changes in back pain, sleep quality, and perceived stress after introduction of new bedding systems.” Journal of Chiropractic Medicine, vol. 8, no. 1, 2009, pp. 1–8. ↩