Diastasis recti (DR) is a common physical change where the abdominal muscles separate, often resulting in a noticeable bulge. This separation involves the stretching of the connective tissue between the muscles. Many people wonder if this muscle separation is responsible for persistent back aches. Diastasis recti can cause back pain by compromising the body’s natural core support system, leading to instability in the spine. This article explores the specifics of this abdominal separation and the mechanisms by which it contributes to lower back discomfort.
Defining Diastasis Recti
Diastasis recti is the separation of the two sides of the rectus abdominis muscle, commonly known as the “six-pack” muscles. This separation occurs along the midline of the abdomen where the connective tissue, called the linea alba, stretches and thins.
While DR is most commonly observed in pregnant and postpartum women due to the expanding uterus and hormonal changes, it is not exclusive to them. The pressure from a growing pregnancy causes the abdominal wall to stretch, and nearly all women experience some degree of separation by the third trimester. Other factors that increase internal abdominal pressure can also lead to DR, including rapid weight changes, chronic strenuous lifting, or certain types of abdominal surgery.
The Biomechanical Link to Back Pain
The connection between diastasis recti and back pain is rooted in the compromised mechanics of the core musculature, which stabilizes the spine. The abdominal muscles, diaphragm, pelvic floor, and deep spinal muscles form the body’s “core canister.” This system generates and regulates intra-abdominal pressure (IAP), which acts like an internal support balloon for the lumbar spine.
When the linea alba is stretched and the rectus abdominis muscles separate, the front wall of this core canister loses tension and structural integrity. This loss means the body cannot efficiently generate the necessary IAP to stabilize the lower back during movement. The resulting weakness forces other muscles, particularly those in the lower back, to work harder to compensate for the instability.
This continuous overcompensation and lack of deep core support leads to excessive load on the lumbar vertebrae, resulting in chronic low back pain. The impairment of the transverse abdominis, a deep core stabilizer, is often implicated in this functional failure, leaving the spine vulnerable to strain during everyday activities.
Recognizing the Signs of Diastasis Recti
The most common physical manifestation of DR is a visible bulge or “pooch” in the midsection that does not resolve with weight loss. This bulge often forms a dome or cone shape when a person attempts to engage their abdominal muscles, such as when sitting up from a lying position. This “doming” occurs as internal pressure pushes abdominal contents through the weakened midline tissue.
Beyond visual signs, people with DR frequently report core weakness or instability, making simple tasks like lifting or rolling over difficult. Associated symptoms include poor posture, pelvic floor dysfunction, and a feeling of softness near the belly button.
Self-Check for DR
A simple self-check involves lying on your back with knees bent, gently lifting your head, and using your fingertips to feel for a gap along the midline of the abdomen. If you can fit two or more fingers into the gap, it suggests the presence of diastasis recti.
Non-Surgical Strategies for Core Stability
The primary management for DR focuses on non-invasive rehabilitation to restore core function and stability. Specialized physical therapy involves exercises that target the deep core muscles, particularly the transverse abdominis. These exercises, such as deep belly breathing with abdominal contraction and gentle pelvic tilts, aim to rebuild the internal support system without straining the midline.
A key focus of rehabilitation is learning to manage intra-abdominal pressure by avoiding movements that cause the abdomen to bulge or dome outward. Exercises involving spinal flexion, such as traditional crunches, sit-ups, and full planks, should be avoided until core function is restored. Exhaling on exertion is an effective technique to help alleviate pressure on the abdominals during movement.
Temporary external support, such as a belly binder or specialized bracing, can provide support in the immediate postpartum period. However, these devices are not a substitute for active muscle strengthening and must be used cautiously to avoid excessive downward pressure on the pelvic floor. The goal of these strategies is to restore dynamic tension in the linea alba, allowing the abdominal wall to function as an effective stabilizer for the spine.