Telemedicine-based individualised aerobic exercise training in Chinese adults with inactive or mildly active inflammatory bowel disease: study protocol for a single-centre, semi-crossover randomised controlled trial

Abstract

Background

Inflammatory bowel disease (IBD) patients in China exhibit critically low levels of physical activity, yet evidence for telemedicine-based aerobic exercise interventions remains scarce, particularly with objective physiological validation.

Methods and analysis

In this single-centre, open-labelled, semi-crossover randomised controlled trial, 28 inactive/mildly active adult IBD patients with low level of baseline physical activity will be randomly assigned to immediate or delayed 12-week telemedicine-based aerobic exercise training. The exercise prescription, stratified by baseline activity level, is designed to progressively elevate physical activity levels to moderate intensity. The telemedicine-based programme used fitness bands synchronised to a mobile app, WeChat-based real-time feedback and online group support and communication. The primary outcome is change in peak oxygen uptake measured by cardiopulmonary exercise testing (CPET). Secondary outcomes include other cardiorespiratory fitness parameters measured by CPET, physical activity level measured by International Physical Activity Questionnaire Short Form, Exercise Benefits/Barriers Scale, clinical disease activity, inflammatory markers, Inflammatory Bowel Disease Questionnaire, nutritional indices, Fatigue Severity Scale and Hospital Anxiety and Depression Score.

Ethics and dissemination

The trial has been approved by the Ethics Committee of the Affiliated Lihuili Hospital of Ningbo University (KY2024SL379-01). Results will be published in peer-reviewed journals and presented at scientific conferences.

Trial registration number

NCT06804733.

STRENGTHS AND LIMITATIONS OF THIS STUDY.

• Semi-crossover design balances ethical equity and statistical power through within-group comparisons.

• Primary outcome uses objective cardiorespiratory fitness parameter measured by cardiopulmonary exercise testing.

• Telemedicine-based training programme enhances feasibility in low-activity populations by integrating wearable technology and digital communication.

• A small sample size may limit generalisation among patients with inflammatory bowel disease.

Introduction

Inflammatory bowel disease (IBD), encompassing Crohn’s disease (CD) and ulcerative colitis (UC), is a chronic inflammatory condition with significant impact on the quality of life of patients.¹ In recent years, IBD has become a global disease with accelerating incidence in newly industrialised countries, including China, posing a substantial burden on healthcare resources.^{2 3} Despite advancements in medical therapies, including new biologic and small-molecule therapies, a considerable proportion of patients will experience loss of response or adverse effect related to medications.⁴ Consequently, an increasing number of IBD patients are seeking complementary therapies to improve their symptoms and quality of life, highlighting the urgent need for effective adjunctive treatments.⁵

Lifestyle modifications are gaining increasing attention in IBD management. Recent evidence suggests that modifiable lifestyle factors, such as healthy diet and physical activity, are associated with reduced risk of disease flares and improved long-term outcomes.⁶ Several studies have demonstrated that physical activity, especially structured exercise programmes, can improve quality of life, reduce fatigue and enhance physical function in IBD patients without exacerbating disease activity.7,10 These findings align with the recommendations from the International Organization for the Study of Inflammatory Bowel Disease, which advocates for increased physical activity as part of a comprehensive management strategy for IBD.¹¹

Despite the recognised health benefits, several studies found that IBD patients have low levels of physical activity in both Western and Asian countries.12,15 Our recent cross-sectional study conducted in east China revealed that the majority of IBD patients engage in minimal to no moderate-to-vigorous physical activity even during disease remission.¹⁶ This low activity level is attributed to both disease-related and non-disease-related barriers. Physical activity outcome expectation is an independent influencing factor. These findings highlight the urgent need for targeted interventions to improve the low physical activity levels among IBD patients, emphasising the importance of overcoming both physical and cognitive barriers to promote a more active lifestyle.

Current research on structured exercise in IBD predominantly comprises aerobic endurance and resistance training. While high-quality randomised controlled trials (RCTs) demonstrated the efficacy of resistance training in improving bone density and muscle strength,^{9 17 18} aerobic interventions face critical limitations. Despite reported benefits in patient-reported outcomes (eg, quality of life and fatigue), high dropout rates challenge their feasibility.^{8 19 20} Furthermore, most studies lacked objective cardiorespiratory assessments, relying instead on subjective measures,^{21 22} which obscured physiological benefits. These gaps underscore the need for personalised aerobic protocols with enhanced adherence strategies and objective physiological validation to optimise IBD management.

Therefore, this study has designed an RCT conducting a 12-week telemedicine-based individualised aerobic exercise training programme targeting inactive or mildly active adult IBD patients with low levels of physical activity in East China. The objectives of the present study are the following:

1. To evaluate whether the 12-week aerobic exercise training can effectively improve the cardiorespiratory capacity of patients and enhance their physical activity levels and exercise-related cognition.

2. To assess the impact of the 12-week aerobic exercise training on disease activity, patient-reported outcomes and nutritional indicators.

3. To evaluate the feasibility, adherence and safety of the 12-week aerobic exercise training.

Methods

Study design

This is a single-centre, open-label, semi-crossover RCT. The reporting of this protocol adheres to the Standard Protocol Items: Recommendations for Interventional Trials 2025 guideline.²³ Eligible patients will be consecutively screened from gastroenterology and IBD clinics at the Affiliated Lihuili Hospital of Ningbo University. The study is scheduled to commence in May 2025 and conclude in May 2027. After the baseline assessment, participants will be randomly assigned in a 1:1 ratio to one of the two groups. Group A will immediately commence a 12-week telemedicine-based, individualised aerobic exercise training programme. Group B will first undergo a 12-week control period, during which participants only receive routine IBD care, followed by the same 12-week aerobic training programme. Throughout the trial, all participants will continue their standard IBD medications and routine care in accordance with clinical guidelines. Figure 1 shows the flow chart of the study, including recruitment and assessment.

Figure 1. Flow chart of the study. 6MWT, 6-min walking test; BCA, body composition analysis; BMI, body mass index; CDAI, Crohn’s Disease Activity Index; CPET, cardiopulmonary exercise test; CRP, C-reactive protein; EBBS, Exercise Benefits/Barriers Scale; FC, faecal calprotectin; FSS, Fatigue Severity Scale; HADS, Hospital Anxiety and Depression Score; IBDQ, Inflammatory Bowel Disease Questionnaire; IPAQ, International Physical Activity Questionnaire; pMS, partial Mayo Score.

Study population

Inclusion criteria

The inclusion criteria for the study are as follows: (1) men and women aged 18–65 years (included); (2) diagnosed with CD or UC for more than 3 months according to the Chinese clinical practice guideline on the management of CD or UC^{24 25}; (3) disease activity in remission or mildly active defined by Crohn’s Disease Activity Index (CDAI; remission <150, mildly active 150–220) for CD patients and partial Mayo Score (pMS; remission 0–1, mildly active 2–4) for UC; and (4) baseline physical activity level is low, measured by the International Physical Activity Questionnaire (IPAQ) Short Form.

Exclusion criteria

The exclusion criteria are as follows: (1) pregnant or breastfeeding or planning to be pregnant within the next 6 months; (2) presence of physical movement disorders or other chronic diseases that limit physical activity; (3) having an ileostomy; and (4) history of anal or intestinal surgery within the past 3 months.

Dropout criteria

The dropout criteria are as follows: (1) serious adverse events during the clinical trial; (2) disease flare-up during the trial, defined as moderate to severe clinical activity; (3) non-compliance with the study protocol or significant deviation from designated training programme; and (4) loss to follow-up.

Randomisation

Randomisation will be stratified by diagnosis to ensure balanced distribution of CD and UC across the groups. SPSS V.26.0 software (IBM Corporation, Armonk, NY, USA) will be used to generate separate random sequences with 1:1 allocation (Group A/B) for each diagnostic stratum, using a randomised block design with a block size of 4. Opaque, sequentially numbered envelopes labelled by diagnosis will be prepared, each containing pre-assigned group codes. On enrolment, the study coordinator will open the next sequential envelope corresponding to the diagnosis of the participant to reveal group allocation.

Blinding

Blinding of participants and researchers to allocation is not possible due to the nature of the intervention. Sample collection, outcome assessment and sample testing are all conducted by designated personnel, who are unaware of the group assignments throughout the study.

Interventions

Stratified exercise prescription

This 12-week telemedicine-based aerobic exercise programme adheres to FITT principles (Frequency, Intensity, Time, Type),²⁶ designed to progressively elevate physical activity levels to moderate intensity, which was defined as 60%–80% maximum heart rate. Given that 50.9% of Chinese IBD patients exhibit low physical activity, with 53.2% scoring zero activity,¹⁶ the intervention incorporates baseline physical activity stratification to enhance adherence.

Baseline physical activity ≥100 metabolic equivalent of task (MET)-min/week

• Phase I (weeks 1–4): ≥5 weekly walking sessions, ≥30 min/session (or ≥150 min/week cumulative), no intensity requirement.

• Phase II (weeks 5–12): ≥5 weekly, ≥30 min/session moderate-intensity sessions (or ≥150 min/week cumulative). Exercise modalities include, but are not limited to, brisk walking, jogging, cycling, swimming, dancing or Tai Chi.

Baseline physical activity <100 MET-min/week

• Phase I (weeks 1–4): ≥3 weekly walking sessions, ≥30 min/session (or ≥90 min/week cumulative), no intensity requirement.

• Phase II (weeks 5–8): ≥5 weekly walking sessions, ≥30 min/session (or ≥150 min/week cumulative), no intensity requirement.

• Phase III (weeks 9–12): ≥5 weekly, ≥30 min/session moderate-intensity sessions (or ≥150 min/week cumulative). Exercise modalities include, but are not limited to, brisk walking, jogging, cycling, swimming, dancing or Tai Chi.

Telemedicine implementation

The intervention uses a multimodal telemedicine platform integrating wearable technology and digital communication. Participants use the Huawei Band V.10.0 (Huawei Technologies Co Ltd, Shenzhen, China) to continuously monitor exercise duration, geolocation trajectory and cardiac parameters (peak/average heart rate), with exercise data automatically synchronised to the Huawei Health app. Participants are required to upload exercise records immediately on completion. Protocol adherence is reinforced via WeChat groups facilitating training reminders, individualised troubleshooting and real-time researcher-participant interactions.

Outcome measures

Primary outcome measures

The primary outcome is change in peak oxygen uptake (VO₂ peak; mL/kg/min) measured by cardiopulmonary exercise testing (CPET) before and after the training or control period. Participants will undergo CPET using an incremental protocol on an electronically braked cycle ergometer (Quark PFT ergo, COSMED, Rome,Italy). After 2 min of unloaded cycling, exercise intensity will be increased every 2–3 min by 15–25 watt progressively until exhaustion. Respiratory parameters and heart rhythm will be monitored continuously throughout the testing.

Secondary outcome measures

1. Other parameters of cardiorespiratory fitness

   1. Other parameters measured by CPET: oxygen uptake at aerobic threshold, VO₂peak per heart rate (VO₂peak/HR) and maximal HR.

   2. A 6-min walking test: maximum walked distance in metres conducted according to Chinese guideline.²⁷

2. Physical activity levels and perception

   1. Physical activity levels will be measured using the Chinese version of IPAQ Short Form covering the past week.²⁸ Time in sedentary state will be recorded using the two questions on sedentary behaviour in the IPAQ Long Form.

   2. The Exercise Benefits/Barriers Scale will be used to assess the perceived benefits and barriers to exercise of participants.²⁹

3. Disease-related secondary outcomes

   1. Clinical disease activity: CDAI for CD patients and pMS for UC will be recorded at baseline and each assessment.³⁰

   2. Health-related quality of life: will be measured using the Inflammatory Bowel Disease Questionnaire.³¹

   3. Inflammatory markers: faecal calprotectin and plasma C-reactive protein will be measured.

4. Nutrition-related indices

   1. Body mass index (kg/m²) will be calculated.

   2. Waist circumference (cm) will be measured.

   3. Plasma haemoglobin level (g/L), serum albumin (g/L), fasting glucose (mmol/L), cholesterol (mmol/L), triglyceride (mmol/L), lipoprotein (mmol/L) and uric acid (mmol/L) will be measured via blood samples drawn from fasted participants at each time point.

   4. Body fat percentage (%) and skeletal muscle mass (kg) will be measured via body composition analysis using the InBody 970 device (InBody Co Ltd, Seoul, South Korea).

5. Fatigue: will be measured using the Fatigue Severity Scale.³²

6. Anxiety and depression: will be measured using the Hospital Anxiety and Depression Scale.³³

Basic characteristic variables

Demographics such as gender, age, height, body weight, occupation and education will be obtained. Vital signs, including resting temperature, blood pressure and heart rate, will be measured. Data on medical history, including age at diagnosis, disease course, past surgery and current medication, will be collected.

Feasibility, adherence and safety assessment

The feasibility, adherence and safety of the telemedicine-based exercise intervention will be rigorously assessed. The percentage of enrolled participants who complete the entire 12-week intervention and the final assessment will be calculated. Researchers will evaluate adherence weekly based on the number of completed sessions, total exercise time and exercise quality. Adherence will be defined as completing a minimum of 10 sessions per 4-week block, culminating in at least 30 sessions over the 12-week intervention period. Brief interviews will be conducted with a subset of participants who complete or do not complete the 12-week intervention, to explore their experiences through the programme and to understand the reasons for non-adherence.

All participants will be instructed to report any adverse events immediately via the WeChat group or directly to the research team. AEs will be specifically monitored for, including but not limited to: exercise-related injuries (eg, musculoskeletal pain and falls), cardiovascular symptoms (eg, dizziness, chest tightness and palpitations) and gastrointestinal symptoms potentially related to disease flare (eg, increased abdominal pain and diarrhoea). Throughout the trial, symptoms, severity, time of occurrence, duration, treatment measures and outcomes will be recorded. In case of any signs of disease flare-up or significant exercise intolerance, participants will be advised to pause exercise and consult both the research team and their gastroenterologist.

Sample size calculation

Sample size calculation is based on the primary outcome of change in VO₂peak after the 12-week aerobic training. Based on the study results of Tew et al, the baseline mean VO₂peak of IBD patients was 28.2 mL/kg/min.⁸ Power analysis was conducted using PASS software (V.11.0, NCSS Statistical Software, Kaysville, UT, USA) with the following parameters: α=0.05 (two-tailed) and power=80%. An increase of 5% in VO₂peak after training compared with baseline was defined as clinically significant (Δ=1.41 mL/kg/min). The SD of VO₂/kg from the CPET literature was 2.19.³⁴ Considering an expected dropout rate of 30%, the sample size was estimated to be 27 through either parametric (paired t-test) or non-parametric (Wilcoxon signed-rank) analyses as appropriate. Therefore, we plan to enrol 14 patients in each group.

Statistical analysis

Statistical analysis will be conducted using SPSS V.26.0 software. Continuous variables will be analysed for normality. Normally distributed data will be presented as mean±SD, while non-normally distributed data will be presented as median (25th–75th percentiles). Categorical variables will be expressed as counts (%). A per-protocol analysis will be conducted, which inherently excludes participants with major protocol deviations or missing primary outcome data. Baseline characteristics between groups will be compared using the unpaired Student’s t-test for normally distributed data, the Mann-Whitney U test for non-normally distributed data, and the χ² test for categorical variables. Changes in outcomes before and after the training or control period will be evaluated using the paired t-test for normally distributed data and the Wilcoxon signed-rank test for non-normally distributed data. Exploratory subgroup analyses will be performed based on baseline variables including the type of IBD (CD vs UC) for all primary and secondary outcomes.

Quality control

To ensure rigorous implementation of the study protocol, a three-tier quality control system is established:

1. Pre-intervention preparation: virtual training sessions before the intervention ensure participants master fitness band operation. Personalised exercise plans are co-developed with participants, specifying location, frequency, intensity and exercise type. Behavioural barriers (eg, motivation and time constraints) are proactively addressed through structured interviews.

2. Real-time adherence monitoring: exercise data from fitness bands are synchronised with a mobile app. Participants must submit exercise records immediately on completing training. Non-compliance triggers (<10 sessions/month, mid-week inactivity or insufficient intensity) prompt researcher contact within 48 hours for personalised guidance.

3. Outcome validation: certified cardiac rehabilitation specialists conduct CPET and report CPET parameters using standardised protocols. All researchers undergo Standard Operating Procedure (SOP) training covering clinical disease activity assessment, WeChat-based documentation procedures and validated questionnaire administration. Weekly cross-checks between wearable data, app logs and self-reports ensure consistency. Discrepancies are resolved through participant verification.

Patient and public involvement

Patients and the public were not involved in the design, conduct and reporting of this trial.

Ethics and Dissemination

The study protocol was reviewed and approved by the Ethics Committee of the Affiliated Lihuili Hospital of Ningbo University (KY2024SL379-01) and registered at ClinicalTrials.gov as NCT06804733. All patients are required to sign an informed consent form (online supplemental file 1) by the investigator prior to enrolment. All participants will be assigned a unique study code to de-identify data. Paper records will be stored securely, and electronic data will be kept on password-protected hospital servers with restricted access. Results will be published in peer-reviewed journals and presented at scientific conferences. The individual de-identified participant data will be shared on publication through request via emailing to the corresponding author.

Discussion

This semi-crossover RCT introduces a novel telemedicine-based framework for delivering individualised aerobic exercise training to adults with inactive or mildly active IBD. By integrating wearable technology, real-time data transmission and WeChat-based support, the protocol addresses critical barriers to physical activity in this population while maintaining quality control through a three-tier system. The stratified exercise prescription, tailored to baseline activity levels, represents an approach to bridging the gap between clinical guidelines and real-world feasibility. The inclusion of objective CPET parameters as primary endpoints advances the field beyond subjective patient-reported outcomes, offering physiological evidence of aerobic exercise efficacy.

The study design holds several strengths. First, the semi-crossover design not only enhances ethical acceptability by allowing delayed intervention for controls but also improves statistical power through within-group comparisons. Second, the multimodal telemedicine platform leverages widely accessible tools (eg, fitness bands and WeChat) to overcome geographical and logistical barriers, aligning with the low physical activity patterns observed in Chinese IBD patients. Third, the integration of motivational interviewing during virtual onboarding and adherence alerts addresses both cognitive and behavioural barriers, potentially reducing dropout rates—a common limitation in prior exercise trials.

However, limitations must be acknowledged. The small sample size may limit generalisability, particularly given the heterogeneity of IBD phenotypes. The open-label design introduces potential performance bias, though outcome assessors are blinded. Technical challenges, such as inconsistent wearable device usage or data synchronisation failures, could compromise compliance monitoring. Additionally, while the 12-week intervention aligns with existing trials, longer follow-up is needed to assess sustained behavioural changes and disease-modifying effects. Regional recruitment from East China may also limit extrapolation to other cultural or healthcare contexts.

Notwithstanding these limitations, the proposed protocol has the potential to yield a replicable blueprint for remote exercise interventions in chronic disease management, which, if effective, could be adapted for other populations with physical activity deficits beyond IBD.