Heavy Lifting and Pelvic Floor Health: What HiRIT Trial Found

For postmenopausal women with low bone mass and pelvic floor symptoms, standard advice can create an impossible choice: protect your bones with heavy resistance and impact training, or protect your pelvic floor by avoiding those same activities. A 2025 randomized trial puts needed evidence into that argument. It found that an eight-month program of supervised high-intensity resistance and impact training did not worsen pelvic-floor-related quality of life compared with low-intensity Pilates-based exercise in women with low bone mass.

That result does not prove heavy lifting is safe for every woman with incontinence or pelvic organ prolapse. The pelvic floor outcomes were secondary, participants started with few symptoms affecting quality of life, and the program had close professional supervision. Still, the trial challenges a broad prohibition that had rested largely on theory rather than randomized clinical evidence.

The advice conflict affects the same women

Bone loss and pelvic floor dysfunction often travel together after menopause. Estrogen decline contributes to bone loss and to less elastic pelvic-floor tissues. Pereira et al. (2025) describe pelvic floor dysfunction as affecting roughly 40% to 50% of postmenopausal women and identify pelvic floor muscle training as a first-line treatment for urinary, bowel, prolapse, and pelvic-pain symptoms.

Meanwhile, resistance and impact exercise matter for bone. A 2021 systematic review and meta-analysis by Ponzano et al. included 53 randomized trials of progressive resistance training in adults age 50 or older with low bone density or a fracture history. It supports resistance training as part of care for people at risk of fracture, while also reporting uncertainty around some outcomes such as falls. An International Osteoporosis Foundation working-group review likewise concludes that physical activity supports bone mineral density and fracture prevention, whereas sedentary time harms bone health.

Pelvic-floor guidelines have often advised women with pelvic floor dysfunction to limit heavy lifting and high-impact activity. The concern is physiologically plausible: hard exertion, particularly with breath-holding or straining, can raise intra-abdominal pressure and increase load on pelvic-floor structures. But the authors of the MEDEX-OP trial note that this conservative recommendation lacked high-quality randomized trial evidence. Plausibility is a reason to test a warning, not a substitute for testing it.

What the MEDEX-OP trial actually tested

Kistler-Fischbacher et al. (2025) randomized 115 postmenopausal women with low bone mass or osteoporosis to bone-targeted high-intensity resistance and impact training, known as HiRIT, or low-intensity Pilates-based exercise. The intervention ran for 35 weeks, roughly eight months, with two sessions each week.

The HiRIT program was not generic gym advice. Participants performed deadlifts, back squats, and overhead presses at more than 80% of one-repetition maximum. They also did assisted impact jumps designed to generate ground-reaction forces greater than four times body weight. The prescribed resistance work was five sets of five repetitions. Exercise Scientists and Physiotherapists supervised the program, and participants completed a two-week technique-accommodation phase before the full protocol.

The comparator mattered, too. The control group did low-intensity Pilates-based exercise rather than no exercise. That makes the trial a comparison between two active programs, not a test of whether movement itself helps pelvic-floor symptoms.

Bone outcomes were the trial's primary focus. Pelvic-floor outcomes were secondary and exploratory, measured with the Pelvic Floor Distress Inventory-20 (PFDI-20) and Pelvic Floor Impact Questionnaire-7 (PFIQ-7). The study reported no reduction in pelvic-floor-related quality of life with HiRIT relative to Pilates. In other words, the trial did not find evidence that this supervised high-load program worsened those questionnaire outcomes.

The available publication details do not provide post-intervention between-group differences, effect sizes, or 95% confidence intervals for those pelvic-floor measures. That omission prevents a precise estimate of how much symptoms changed, or how confidently the trial can exclude a clinically meaningful worsening.

The baseline scores explain why caution remains warranted

The groups began with similar symptom burdens. Mean PFDI-20 scores were 30.5 ± 34.5 in the HiRIT group and 34.6 ± 35.9 in the Pilates group (p = 0.28). Mean PFIQ-7 scores were 4.3 ± 12.4 and 3.9 ± 11.1, respectively (p = 0.92). Those balanced starting points support a fair comparison.

They also reveal the study's largest limitation. The PFIQ-7 ranges to 300, and the combined baseline mean was about 4.1. Participants therefore had very little pelvic-floor impact on quality of life at enrollment. A scale near its floor has little room to register further decline. The trial's reassuring finding applies most directly to women with low baseline pelvic-floor quality-of-life impairment, not automatically to women with substantial daily leakage, symptomatic stage II or greater prolapse, or complex postsurgical anatomy.

Only 13% of participants had a history of pelvic organ prolapse. The trial reported exploratory signals that may have favored HiRIT in that subgroup, but exploratory subgroup observations cannot establish treatment safety or benefit for prolapse. The study also was powered for bone outcomes, not to rule out smaller pelvic-floor harms with high statistical confidence.

What the trial changes—and what it does not

MEDEX-OP moves the evidence base beyond a purely theoretical warning. In this specific population, using a specific supervised protocol, researchers observed no worsening in pelvic-floor quality of life over 35 weeks. That is more informative than assuming that high intra-abdominal pressure must cause clinically measurable harm.

It does not erase the mechanism behind the concern. Heavy lifting can raise intra-abdominal pressure, and clinicians should take new or worsening symptoms seriously. Nor does the absence of a harmful randomized trial in this evidence base mean the risk is zero. Cross-sectional reports in strength and impact athletes may be relevant, but they cannot establish whether training caused symptoms; they may also reflect selection, training practices, childbirth history, or other differences. They are not a replacement for a pelvic-floor-primary randomized trial.

The evidence also should not be stretched into a promise that HiRIT treats pelvic floor dysfunction. The trial assessed whether HiRIT worsened pelvic-floor quality of life relative to Pilates; it was not designed to show that heavy lifting cures incontinence or prolapse. Pelvic floor muscle training remains a direct treatment option, and Pereira et al. found that a digital approach to postmenopausal pelvic-floor care was feasible and associated with meaningful symptom improvement in a prospective cohort. A cohort can show change over time, but it cannot prove that the digital program caused every improvement.

Inactivity has costs, too

The practical comparison is rarely between lifting and a risk-free life on the couch. Avoiding resistance and impact exercise can leave bone health undertreated, particularly in women already at risk for osteoporosis. It may also shrink confidence and daily function.

Pelvic-floor symptoms themselves deserve treatment rather than resignation. A 2025 single-center cohort study by Chen et al. linked untreated pelvic floor dysfunction with worsening quality of life over time, including bowel, bladder, and prolapse symptom domains. That association does not show that exercise restriction causes deterioration. It does show why a blanket activity ban is a poor substitute for assessment and treatment.

Postmenopausal pelvic-floor care also varies by anatomy, symptom severity, hormone status, and treatment history. An ICI-RS report on pelvic-floor surgery describes ongoing uncertainty around hormonal, microbial, and other factors that may influence surgical outcomes. The broader lesson is ordinary but useful: pelvic-floor dysfunction is not one condition with one exercise rule.

A sensible way to use this evidence

For a postmenopausal woman with low bone mass and mild pelvic-floor symptoms, MEDEX-OP supports discussing supervised high-intensity resistance and impact training instead of automatically ruling it out. Reproducing the study conditions makes sense: qualified supervision, a gradual technique phase, carefully selected impact work, and attention to symptoms during progression.

• Seek assessment from a clinician or pelvic-health physiotherapist when leakage, prolapse symptoms, pelvic pain, or bowel symptoms interfere with life.
• Learn lifting and breathing technique before attempting heavy loads. The trial used supervised training; it did not test an unsupervised maximal-lifting program.
• Consider combining bone-focused training with pelvic floor muscle training, including remote care when appropriate.
• Use individualized clinical guidance if you have symptomatic moderate-to-severe prolapse, high-grade incontinence, recent pelvic-floor surgery, or a condition that changes connective-tissue integrity.

The evidence does not require women with low bone mass and mild pelvic-floor symptoms to choose between their skeleton and their pelvic floor. It supports a supervised attempt at both forms of care, while acknowledging that the women most affected by pelvic-floor dysfunction still need better trials.

The next study should make pelvic-floor outcomes primary, enroll women with clinically meaningful symptoms, report effect estimates and confidence intervals, and follow participants long enough to detect harms or benefits that questionnaires near the floor can miss. Until then, MEDEX-OP offers a narrow but valuable correction: heavy, bone-targeted training did not worsen pelvic-floor quality of life in the women it studied.