In males, involuntary or voluntary ischiocavernosus muscle contractions after erection lead to intracavernous blood pressures much higher than the systolic pressure, which builds and maintains penile rigidity. Thus, erectile dysfunction may be due in part to ischiocavernosus muscle atrophy and may be treated by rehabilitation interventions. The objective of this study was to determine whether pelvic-floor muscle strengthening interventions might be related to increases in intracavernous pressure that would increase penile rigidity. One hundred twenty-two men with isolated erectile dysfunction and 108 men with isolated premature ejaculation participated (no neuromuscular diseases or previous perineal rehabilitation). Thirty-minute sessions of voluntary contractions combined with electrical stimulation were designed to increase ischiocavernosus muscle strength (monitored through intracavernous pressure increase). A linear mixed-effects model per group analyzed separately, then jointly, the maximum change in pressure (ΔP) and the maximum baseline (ie, respectively, the average contraction-generated difference in intracavernous pressure and the intracavernous pressure plateau at full erection, both measured during the highest moving average of the best 2 minutes of each session). Over 20 sessions, the maximum ΔP increased in erectile dysfunction as well as in premature ejaculation (87% and 88%, respectively, in men with positive trends). The maximum baseline also increased (99% and 72%, respectively, in men with positive trends). The joint modeling suggestsed that the mean expected progressions of the intracavernous pressure after 5 sessions in erectile dysfunction and premature ejaculation were 62.85 and 64.15 cm H2O, respectively.
Pelvic-floor muscle rehabilitation was found to be beneficial in erectile dysfunction. However, its effects on symptoms of premature ejaculation, despite intracavernous pressure gains, were much more difficult to assess. The definitive proof of its benefits necessitates somewhat challenging-to-design clinical trials.