Trampoline-Induced Changes in Pelvic Structure and Continence

Recruiting

• Conditions: Urinary Continence; Urinary Incontinence; Urinary Incontinence (UI); Urinary Incontinence , Stress

• Registration Number: NCT07183800
• Lead Sponsor: University of Ottawa

Brief Summary

The goal of this clinical trial is to evaluate whether a short bout of high-intensity trampoline jumping induces urinary leakage or measurable changes in pelvic floor morphology in active females aged 18-40 who do not report symptoms of urinary incontinence. The main questions it aims to answer are:

Hypothesis 1: Does a single 10-minute trampoline protocol result in acute changes in pelvic floor structure, including bladder neck position, levator plate length, and/or posterior urethrovesical angle (PUVA)?

Hypothesis 2: Do participants report any urinary leakage during the jumping protocol, despite being asymptomatic at baseline?

Hypothesis 3: Do pelvic morphology changes recover within 30 minutes post-jumping, or do alterations persist?

Researchers will perform within-subject comparisons at multiple time points (pre-jump, immediately post-jump, and 30 minutes post-jump) using transperineal ultrasound imaging to assess structural changes.

Participants will:

* Attend one laboratory visit

* Complete baseline pelvic health questionnaires (ICIQ-UI Short Form and PFD Sentinel).

* Undergo 2D transperineal ultrasound imaging in the standing position at rest, immediately post-jumping, and 30 minutes post-jumping.

* Perform a 10-minute high-intensity jumping protocol on a mini-trampoline, while heart rate and perceived exertion are monitored.

* Verbally report any urine leakage during jumping using standardized descriptors.

Detailed Description

Urinary incontinence (UI) has traditionally been associated with postpartum or older women; however, growing evidence highlights its prevalence among young, physically active females - even in those without a history of pelvic floor dysfunction or childbirth (Teixeira et al., 2018; Pires et al., 2020). High-impact physical activities such as running, jumping, and trampolining have been shown to increase intra-abdominal pressure, placing acute mechanical stress on the pelvic floor and potentially contributing to urinary leakage (Shaw et al., 2014). While the relationship between high-impact exercise and stress urinary incontinence (SUI) has been explored in terms of prevalence, less is known about the acute, real-time mechanical effects of impact loading on pelvic floor structures in asymptomatic individuals (Mattos et al., 2018; Bo, 2004).

This study aims to investigate whether a 10-minute high-intensity trampoline protocol induces measurable changes in pelvic morphology - specifically in bladder neck position, levator plate length, and/or posterior urethrovesical angle (PUVA) - in physically active females aged 18-40 who do not report urinary incontinence symptoms. These anatomical parameters are indicators of pelvic floor support and dysfunction, and their change under load may signal early mechanical strain on the pelvic floor (Shaw et al., 2014; McLean et al., 2020).

Participants will undergo a single study session involving a baseline transperineal ultrasound assessment, a 10-minute jumping bout, and follow-up ultrasound assessments immediately, and 30 minutes post-exercise. Urinary leakage is monitored during jumping via verbal self-report every 2 minutes, with descriptive classifications such as "drops," "squirt," or "gush." Jumping intensity is tracked using the Borg RPE scale (Cabral et al., 2020) and heart rate monitoring via Apple Watch, which has demonstrated acceptable validity for exercise heart rate tracking (Zhang et al., 2020; Gillinov et al., 2017).

A repeated-measures design will be used to assess within-subject changes in pelvic morphology, with participants serving as their own control across time points. Data will be analyzed using repeated-measures ANOVA to determine statistically significant changes, with Cohen's d effect sizes calculated to assess magnitude of effect (Serdar et al., 2021). Leakage data will be reported descriptively.

Ultimately, this study will generate foundational data on the immediate biomechanical response of the pelvic floor to high-impact activity. These findings may help identify early indicators of pelvic floor strain, even in women without symptomatic UI, and could inform future screening and prevention strategies for active female populations (Goldstick \& Constantini, 2013; Brennand et al., 2017).

Study Timeline

• Status Verified: 2025-07
• Study Start: 2025-07-16
• Study First Submitted: 2025-09-12
• Study First Submitted QC: 2025-09-12
• Last Update Submitted: 2025-09-12
• Study First Posted: 2025-09-19
• Last Update Posted: 2025-09-19
• Primary Completion: 2025-12-31
• Study Completion: 2026-04-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 30

Inclusion Criteria

• Aged 18-40
• Engage in regular physical activity or sport
• Do not experience frequent urinary leakage (no more than once per month during exercise, coughing, or sneezing)
• Can complete a 10-minute jumping protocol

Exclusion Criteria

• Currently pregnant or have been pregnant in the past 6 months
• Have cardiac, pulmonary, metabolic, and/or neurological conditions
• Have a lower body injury that limits your ability to jump
• Have had a hysterectomy and/or incontinence surgery

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Assessing whether a short-duration trampoline protocol induces urinary leakage in active females.	Urinary leakage is assessed during the 10-minute jumping protocol on the single lab visit.	Urinary leakage is assessed via self-report during a 10-minute high-intensity trampoline jumping protocol. Every 2 minutes, participants are verbally prompted to report whether they experienced leakage, and to classify it using standardized descriptors ("drops," "squirt," or "gush"). Leakage severity is indexed based on the timing of first report, frequency of episodes, and qualitative volume descriptors. Descriptive statistics will be used to report the proportion of participants who leak, frequency of leakage, and severity profiles.

Secondary Outcome Measures

Name	Time	Method
Assessing whether a short-duration trampoline protocol induces acute changes in bladder neck morphology in active females.	Bladder neck morphology outcomes are assessed across a single session spanning approximately 45-60 minutes (baseline through 30 minutes post-exercise).	Bladder neck morphology is measured at three time points (pre-jumping, immediately post-jumping, and 30 minutes post) using 2D transperineal ultrasound imaging. Repeated-measures ANOVA will be used to determine significant changes in bladder neck morphology across time points. Cohen's d effect sizes will be calculated to assess the magnitude of observed changes.
Assessing whether a short-duration trampoline protocol induces acute changes in levator plate length in active females.	Levator plate length outcomes are assessed across a single session spanning approximately 45-60 minutes (baseline through 30 minutes post-exercise).	Levator plate length is measured at three time points (pre-jumping, immediately post-jumping, and 30 minutes post) using 2D transperineal ultrasound imaging. Repeated-measures ANOVA will be used to determine significant changes in levator plate length across time points. Cohen's d effect sizes will be calculated to assess the magnitude of observed changes.
Assessing whether a short-duration trampoline protocol induces acute changes in the posterior urethrovesicle angle (PUVA) in active females.	Posterior urethrovesicle angle (PUVA) outcomes are assessed across a single session spanning approximately 45-60 minutes (baseline through 30 minutes post-exercise).	The posterior urethrovesicle angle (PUVA) is measured at three time points (pre-jumping, immediately post-jumping, and 30 minutes post) using 2D transperineal ultrasound imaging. Repeated-measures ANOVA will be used to determine significant changes in the PUVA across time points. Cohen's d effect sizes will be calculated to assess the magnitude of observed changes.

Trial Locations

Locations (1)

University of Ottawa - Lees Campus; 🇨🇦 Ottawa, Ontario, Canada