International Urogynecology Journal

, Volume 19, Issue 6, pp 773–782 | Cite as

Clarification and confirmation of the Knack maneuver: the effect of volitional pelvic floor muscle contraction to preempt expected stress incontinence

  • Janis M. MillerEmail author
  • Carolyn Sampselle
  • James Ashton-Miller
  • Gwi-Ryung Son Hong
  • John O. L. DeLancey
Original Article


The aim of the study was to determine the immediate effect of timing a pelvic muscle contraction with the moment of expected leakage (the Knack maneuver) to preempt cough-related stress incontinence. Women performed a standing stress test using three hard coughs without and then with the Knack maneuver. Volume of urine loss under both conditions was quantified with paper-towel test. Two groups of women were tested: nonpregnant women (n = 64) and pregnant women (n = 29). In nonpregnant women, wetted area decreased from a median (range) of 43.2 (0.2–183.7) cm2 without the Knack maneuver to 6.9 (range of 0 to 183.7 cm2) with it (p < 0.0001); while in pregnant women it decreased from 14.8 (0–169.7) cm2 to 0 (0–96.5) cm2, respectively (p = 0.001). This study confirms the effect from the Knack maneuver as immediate and provides a partial explanation for early response to widely applied pelvic muscle training regimens in women with stress incontinence.


Urinary incontinence Pelvic muscle training Stress incontinence Pelvic muscle education Kegel Pregnancy 



The study was supported by the National Institutes of Health/National Institute for Nursing Research, Grant # R01 NR04007 (PI Carolyn Sampselle, PhD) and National Institutes of Health/National Institute for Child Health and Human Development, Grant #P50 HD044406 (Director John DeLancey, MD).

Conflicts of interest



  1. 1.
    Miller JM, Ashton-Miller JA, DeLancey JO (1998) A pelvic muscle precontraction can reduce cough-related urine loss in selected women with mild SUI. J Am Geriatr Soc 46:870–874PubMedGoogle Scholar
  2. 2.
    Cammu H, Van Nylen M, Derde MP, DeBruyne R Amy JJ (1991) Pelvic physiotherapy in genuine stress incontinence. Urology 38(4):332–337PubMedCrossRefGoogle Scholar
  3. 3.
    Hay-Smith EJC, Dumoulin C (2006) Pelvic floor muscle training versus no treatment, or inactive control treatments, for urinary incontinence in women. Cochrane Database Syst Rev, Issue 1. Art. No.:CD005654. DOI  10.1002/14651858.CD005654
  4. 4.
    Bö K (2004) Pelvic floor muscle training is effective in treatment of female stress urinary incontinence, but how does it work? Int Urogynecol J Pelvic Floor Dysfunc 15(2):76–84CrossRefGoogle Scholar
  5. 5.
    Burgio KL, Zyczynski H, Locher JL, Richter HE, Redden DT, Wright KC (2003) Urinary incontinence in the 12-month postpartum period. Obstet Gynecol 102(6):1291–1298PubMedCrossRefGoogle Scholar
  6. 6.
    Wyman JF, Fantl JA, McClish DK, Bump RC (1998) Comparative efficacy of behavioral interventions in the management of female urinary incontinence. Continence Program for Women Research Group. Am J Obstet Gynecol 179(4):999–1007PubMedCrossRefGoogle Scholar
  7. 7.
    Burgio KL (1990) Behavioral training for stress and urge in continence in the community. Gerontology 36(2):27–34PubMedCrossRefGoogle Scholar
  8. 8.
    Burton JR, Pearce KL, Burgio KL, Engel BT, Whitehead WE (1988) Behavioral training for urinary incontinence in elderly ambulatory patients. J Am Geriatr Soc 36(8):693–698PubMedGoogle Scholar
  9. 9.
    Bö K, Talseth T (1996) Long term effect of pelvic floor muscle exercise 5 years after cessation of organized training. Obstet Gynecol 87:261–265PubMedCrossRefGoogle Scholar
  10. 10.
    Miller JM, Ashton-Miller JA, DeLancey JO (1998) Quantification of cough-related urine loss using the paper towel test. Obstet Gynecol 91(5):705–709PubMedCrossRefGoogle Scholar
  11. 11.
    Neumann P, Blizzard L, Grimmer K, Grant R (2004) Expanded paper towel test: an objective test of urine loss for stress incontinence. Neurourol Urodyn 23(7):649–655PubMedCrossRefGoogle Scholar
  12. 12.
    Bland JM, Altman DG (1986) Statistical methods for assessing agreement between two methods of clinical measurement. Lancet i:307–310Google Scholar
  13. 13.
    Miller JM, Perucchini D, Carchidi LT, DeLancey JO, Ashton-Miller J (2001) Pelvic muscle contraction during a cough and decreased vesical neck mobility. Obstet Gynecol 97:255–260PubMedCrossRefGoogle Scholar
  14. 14.
    Miller JM, Umek WH, DeLancey JO, Ashton-Miller JA (2004) Can women increase urethral closure pressures without their pubococcygeus muscles? Am J Obstet Gynecol 191(1):171–175PubMedCrossRefGoogle Scholar
  15. 15.
    Bö K, Talseth T (1997) Change in urethral pressure during voluntary pelvic floor muscle contraction and vaginal electrical stimulation. Int Urogynecol J Pelvic Floor Dysfunc 8(1):3–6 CrossRefGoogle Scholar
  16. 16.
    Bö K, Berghmans LC (2000) Nonpharmacologic treatment for overactive bladder-pelvic floor exercises. Urology 55(5A supplement):7–11PubMedCrossRefGoogle Scholar
  17. 17.
    DeLancey JOL, Kearney R, Chou Q, Speights S, Binno S (2003) The appearance of levator ani muscle abnormalities in magnetic resonance images after vaginal delivery. Obstet Gynecol 101(1):46–53PubMedCrossRefGoogle Scholar
  18. 18.
    Kegel A (1948) Progressive resistance exercise in the functional restoration of the perineal muscles. Am J Obstet Gynecol 56(2):238–248PubMedGoogle Scholar

Copyright information

© International Urogynecology Journal 2007

Authors and Affiliations

  • Janis M. Miller
    • 1
    • 2
    Email author
  • Carolyn Sampselle
    • 1
  • James Ashton-Miller
    • 3
  • Gwi-Ryung Son Hong
    • 4
  • John O. L. DeLancey
    • 2
  1. 1.School of NursingUniversity of MichiganAnn ArborUSA
  2. 2.Obstetrics & GynecologyUniversity of MichiganAnn ArborUSA
  3. 3.Mechanical EngineeringUniversity of MichiganAnn ArborUSA
  4. 4.Department of NursingCollege of Medicine, Hanyang UniversitySeoulSouth Korea

Personalised recommendations