Abdominal hypopressive technique to manage the symptoms of a leaky bladder may not actually work, conclude experts.
The abdominal hypopressive technique, or AHT for short, has been taught to more than 1500 coaches in 14 countries, and has been widely publicised on TV and on social media.
AHT is a breathing and corrective postural technique, which aims to lessen abdominal pressure, the theory being that this can involuntarily activate muscles in the abdominal wall and pelvic floor, so reducing urinary incontinence and pelvic organ prolapse.
It involves breathing in deeply through the diaphragm, and contracting the abdominal muscles after fully breathing out and holding the breath before relaxing.
AHT is one of several methods based on breathing exercises and correction of body posture, which have been proposed as ways of preventing or treating prolapse and urinary incontinence. Others include Pilates and Tai Chi.
But the trial data indicate limited or "questionable" effects for these techniques, and in the case of AHT, no evidence at all, including when added to pelvic floor muscle exercises, for which there is strong evidence of effectiveness.
Pelvic floor muscle exercises were first described in the late 1940s by Arnold Kegel. "There is undoubtedly a worldwide huge interest of the public and the clinical community in AHT," write Professor Kari Bø, of the Norwegian School of Sport Science, Oslo, Norway, and Mr Sa?l Martín-Rodríguez, of the College of Physical Education, Las Palmas de Gran Canaria, Spain.
"However, to date, AHT lacks scientific evidence to support its benefits. At this stage, AHT is based on a theory with 20 years of clinical practice," they continue.
And they conclude: "At present, there is no scientific evidence to recommend its use to patients. This particular treatment currently illustrates the phenomenon that not all recommended treatments are evidence based."