# Effect of zero-time exercise intervention on endometrial receptivity in women with thin endometrium a single-center randomized sham-controlled trial

## TL;DR

A new exercise method called zero-time exercise improves endometrial thickness and receptivity in women with thin endometrium undergoing fertility treatments.

## Contribution

ZTEx is introduced as a safe, time-efficient, and equipment-free exercise intervention for thin endometrium in ART patients.

## Key findings

- ZTEx significantly increased endometrial thickness compared to a sham intervention after 12 weeks.
- ZTEx improved multiple endometrial receptivity-related vascular indices in the experimental group.
- No adverse events were reported, confirming the safety of ZTEx.

## Abstract

Current therapeutic strategies for thin endometrium have inherent limitations, and zero-time exercise (ZTEx), a professionally guided fragmented low-intensity exercise, may serve as a novel adjunctive intervention for its management.

This was a single-center randomized sham-controlled trial. Eligible patients undergoing ART were randomly divided into an experimental group (receiving ZTEx intervention) and a control group (receiving sham intervention). The ZTEx intervention was delivered over 12 weeks, featuring fragmented, low-intensity exercises under professional guidance. Key indicators of endometrial health—including endometrial thickness and endometrial receptivity-related parameters—were monitored throughout the intervention period.

After 12 weeks of intervention, ANCOVA (adjusted for baseline values) revealed that the experimental group had a significantly greater endometrial thickness than the control group (6.67 ± 1.15 mm vs. 5.88 ± 1.17 mm, P < 0.001). Concurrently, multiple endometrial receptivity-related indices improved significantly in the experimental group (all P < 0.05), including uterine artery hemodynamic parameters (pulsatility index [PI], resistance index [RI], systolic/diastolic ratio [S/D]) and vascularization indices (vascularization index [VI], flow index [FI], vascularization-flow index [VFI]).No exercise-related adverse events were reported over the course of the trial, confirming the safety profile of ZTEx.

Supported by rigorous statistical analyses, ZTEx effectively enhances endometrial thickness and receptivity in ART patients with thin endometrium. Its key advantages—safety, feasibility, and no need for additional time or equipment—make it a promising adjuvant intervention in clinical ART settings.

The online version contains supplementary material available at 10.1007/s00404-026-08385-4.