August 17, 2017
Re: Flattening The 'Mummy Tummy' With 1 Exercise, 10 Minutes A Day | NPR | 7 August 2017
We read your article, Flattening The 'Mummy Tummy' With 1 Exercise, 10 Minutes A Day, and enjoyed the perspective on how simple exercises or a change in behavior has improved someone's pain and perception of themselves. We agree that mothers can benefit from exercise at any stage and support efforts to help them do so safely, effectively, and without fear of being injured.
However, we feel it is our duty to point out our concerns with some of the article's conclusions, as they may be misleading to women seeking out help for the condition of diastasis recti.
The article mentioned a concern for mothers with diastasis recti having an increased risk for low back pain. However, the research identified in the article as the "Norwegian study" by Sperstad et al1 actually stated the opposite. In their study of 300 first-time mothers, they noted:
- No risk factors when comparing women with or without diastasis recti
- No increased likelihood of diastasis recti with increased heavy lifting
- No difference in low back pain prevalence in those with or without diastasis recti
Of particular concern is Leah Keller’s statement that casts unnecessary fear on mothers looking to get back into shape, and is not supported by evidence: "You have to be very careful," she says. "For example, please don't ever again in your life do crossover crunches or bicycle crunches. They splay your abs apart in so many ways."
Recent literature by Lee and Hodges2 looked at integrating transverse abdominal muscle (which is the main muscle mentioned in your article) and rectus abdominal muscle contraction to see what effect the muscles have on the linea alba (center line of the abdomen). They demonstrated that:
- Contracting just the transverse abdominal muscle actually increases the interrecti distance, thereby tensioning the linea alba3 (increasing abdominal muscle separation), which may potentially improve how well the abdominals can handle load.
- Contracting the rectus abdominis with a curl-up reduces the interrecti distance (decreasing abdominal muscle separation).
These conclusions were made using ultrasound measurements, which is shown to have greater accuracy than digital or caliper measurement. As you can see, postpartum rehabilitation is a multimuscle integrative process, not as simple as the "1 muscle-1 exercise approach" proposed by Keller. If done properly, the crossover crunches and bicycle crunches could actually help a woman restore the strength to all of her abdominal muscles.
Finally, the research by Sharma and Keller is misrepresented:
- Only 29 of the 63 women mentioned were postpartum in the pilot study presentation.
- The presentation was a retrospective case series with no mention of how diastasis recti was measured.
- No control group of postpartum women who did other exercises or no exercise was identified.
Diastasis recti is not well understood and more research, including standardization of assessment, etiology, and clinical practice guidelines, is required. In the meantime, a women’s health physical therapist trained in the assessment and treatment of patients concerned about diastasis recti can be beneficial both during and after pregnancy to guide participation in exercise.
Your readers can find a women's health physical therapist in their area on APTA's patient information website, MoveForwardPT.com.
Sharon L. Dunn, PT, PhD
American Physical Therapy Association
Patricia Wolfe, PT, MS
Section on Women’s Health, American Physical Therapy Association
- Sperstad JB, Tennfjord MK, Hilde G, Ellstrom-Engh M, Bo K. Diastasis recti abdominis during pregnancy and 12 months after childbirth: prevalence, risk factors and report of lumbopelvic pain. Br J Sports Med. 2016;50:1092–1096.
- Lee D, Hodges PW. Behavior of the linea alba during a curl-up task in diastasis rectus abdominis: an observational study. J Orthop Sports Phys Ther. 2016;46:580–589.
- Pascoal AG, Dionisio S, Cordeiro F, Mota P. Inter-rectus distance in postpartum women can be reduced by isometric contraction of the abdominal muscles: a preliminary case-control study. Physiotherapy. 2014;100:344-348.