Pelvic floor and abdominal muscle responses during hypopressive exercises in women with pelvic floor dysfunction.

Aim: To measure the neuromuscular activation of the pelvic floor and abdominal muscles concurrently with vaginal closure forces induced during a hypopressive exercise (HE) and to identify the contribution of the HEs sequences (posture and maneuver) in the muscle's activation.

Methods: A cross-sectional study design was employed. Sixty-six women who had participated in a physical therapy program focused on HEs were recruited. Pelvic floor muscle (PFM) activation was measured using surface electromyography (sEMG) in supine and in the orthostatic position, and vaginal closure force was measured through vaginal dynamometry in supine. Activation of the abdominal, gluteal, and hip adductor muscles was measured using sEMG. Maximum effort voluntary contractions (MVCs) of the PFMs and reference contractions of the abdominal and hip muscles were acquired for normalization purposes. A HE was then performed in a supine position with one leg raised, then in an orthostatic position.

Results: During the supine HE, the peak PFM sEMG amplitude was 74.4% to 86.5% (49.6%-109.6%) of MVC, the peak vaginal closure force was between 51.2% and 55.7% (95.5%-382.9%) of MVC, and the muscles of the lateral abdominal wall were activated between 25.4% and 35.3% of the reference contraction. During the orthostatic HE, PFM activation was 61.4% (40.1%-105.6%) of MVC, and the lateral abdominal wall muscles contracted at 22.8% of the reference activation level.

Conclusions: The PFMs, abdominal, gluteal, and adductor muscles are activated during the performance of a HE. The activation level of the PFMs and abdominal muscles is likely insufficient to result in strength gains; however, they could have an endurance effect.