Diastasis Recti: The Tummy Gap Explained Simply

You check your tummy a few weeks after birth and notice a gap or ridge along your midline when you lift your head. Or perhaps someone at mother's group mentioned diastasis recti and you felt a flutter of anxiety about whether you have it. This article exists to give you accurate, un-alarming information - because diastasis recti is extremely common, frequently misunderstood, and responds well to the right approach.

What diastasis recti actually is

Diastasis recti (also called diastasis rectus abdominis, or DRA) is a separation of the two rectus abdominis muscles along the midline of your abdomen. The "gap" is not actually a gap in muscle - the muscles themselves stay intact. What changes is the linea alba, the band of connective tissue that connects the two sides of your six-pack muscles down the middle of your abdomen.

During pregnancy, as your uterus expands, the linea alba stretches and widens to accommodate the growing baby. This is completely normal and happens to virtually all women in the third trimester. Studies suggest that 100% of women have some degree of diastasis at 35 weeks. The question at the postnatal stage is not whether you have one, but whether it is affecting your function.

Research by Diane Lee and Paul Hodges has shifted the field significantly. We now understand that the width of the gap is less important than the tension and load transfer capacity of the linea alba. A wide gap with good tension can function perfectly well; a narrow gap with poor tissue quality can be functionally problematic.

How to do a self-check

A basic self-check gives you useful information, though it cannot replace a physiotherapy assessment. Here is how to do it:

Lie on your back with your knees bent. Place two fingertips horizontally across your midline at your navel level. Slowly lift your head and shoulders as if beginning a crunch - do not go all the way up. Feel for the edges of your abdominal muscles closing in around your fingers. Note how many fingers fit in the gap, and whether the tissue beneath your fingers feels firm and taut, or soft and yielding.

A gap of one to two finger-widths with firm tissue is generally considered functional. A gap wider than two to three fingers, or a gap of any width where the tissue feels soft, domes, or bulges significantly under your fingers, warrants physiotherapy assessment.

Also check above and below the navel - the width of the separation can vary significantly along the length of the linea alba.

What exercises are safe - and what to avoid

The exercises that place the most demand on linea alba integrity are those that generate high intra-abdominal pressure with a pulling-apart force on the midline. These include traditional crunches and sit-ups, double leg lifts, heavy deadlifts and squats (in the early postnatal period), and some Pilates movements that load the abdominals without adequate support.

This does not mean you cannot exercise - it means you need to progress appropriately. Safe starting points include breathing exercises that reconnect your diaphragm and pelvic floor, gentle core activation (transversus abdominis) in supported positions, modified bridging and clamshell exercises, and walking with good posture.

The goal is not to close the gap by brute force. The goal is to restore tension and load-transfer capacity to the linea alba through progressive, well-managed rehabilitation. As your tissue regains functional strength, you can progressively return to more demanding activities.

When does diastasis recti resolve?

For many women, the gap narrows naturally in the weeks after birth as oestrogen levels stabilise and connective tissue remodels. However, resolution of the gap width does not always mean the function has returned. And for some women, a functionally significant diastasis persists for months or years without targeted rehabilitation.

Symptoms associated with a functionally significant diastasis include a visible dome or ridge along the midline when exercising, difficulty generating intra-abdominal pressure, persistent lower back pain, pelvic floor symptoms (leaking, heaviness), and feeling that your core does not work reliably under load.

The bigger picture

Diastasis recti is one part of the postnatal recovery picture, not the whole story. The pelvic floor, abdominal wall, diaphragm, and deep spinal muscles all work together. Rehabilitation that addresses the whole system - which is what the Postnatal Recovery programme does - tends to produce better outcomes than focusing solely on closing a gap.

If you are concerned about your diastasis, please seek assessment from a pelvic floor or women's health physiotherapist. An accurate baseline gives you a clear starting point and helps you track your progress with confidence.