High Intensity Exercise in Children With MCADD (MCADD-EX)

March 19, 2026 updated by: University Hospital, Ghent

Medium-Chain Acyl-Coa Dehydrogenase Deficiency (MCADD) and Exercise

Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is a rare genetic disorder affecting the body's ability to break down certain fats (β-oxidation) for energy, leading to symptoms like hypoketotic hypoglycaemia, jaundice, cardiomyopathy and seizures. responsible for the dehydrogenation step of fatty acids with chain lengths between 6 and 12 carbons as they undergo beta-oxidation in the mitochondria. Deficiency in MCAD can result in energy deficiency, the accumulation of acylcarnitine's and low serum carnitine concentrations.

The primary objective of the pilot study is to analyse the effects of high-intensity exercise (cardiopulmonary exercise testing (CPET) & high intensity circuit exercises ) on metabolic parameters and safety. This research is a pilot study comparing four patients with MCADD to four control subjects with the same characteristics. Blood samples are collected for analysis of substrate utilization.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

The primary objective of the study is to analyse the effects of high-intensity exercise (CPET & high intensity circuit exercises) on metabolic parameters and safety. Since exercise is tested approximately two hours after a meal, we expect few symptoms, as fat metabolism is only minimally engaged at this intensity. Of interest could be the recovery from exercise, as fat metabolism is presumably activated during this phase.

Each MCADD-patient will attend two experimental visits. On the day of the first visit, the patient will arrive at UZ Gent after 1.5-hours following the meal. After 30 minutes, they will perform a cardiopulmonary exercise test (CPET) on a cycle ergometer. The standard CPET protocol that will be used is as follows: first, three minutes of cycling at a constant load (body weight (kg) / 2) in Watts), followed by a maximal exercise test (Ramp protocol: (body weight (kg) / 4) in Watts per minute). During the cycling test, gas exchange (spirometry) is measured, and an ECG is taken. If no symptoms are observed, the patient may return home. On the second test day, two hours before the test, a breakfast will be consumed. 1.5-hours following the meal, the patient will arrive at UZ Gent, where a heart monitor will be placed, and an intravenous line will be inserted. Following this, the patient will undergo a high-intensity exercise circuit. Blood samples will be taken before and after the exercise at various intervals: immediately, after 30 minutes, 1 hour, and 1.5-hours. Also, RER will be determined at each timepoint using indirect calorimetry. If no symptoms appear, the patient may return home. The patient will report symptoms for the 48 hours following the test. In the blood samples, measures of substrate utilization will be monitored: Glucose, lactate, acylcarnitine levels, free fatty acids (FFA). Also a marker of muscle damage will be assessed (creatine kinase). Additional measures include: anthropometric measurements, including weight and height, physical activity through the children physical activity questionnaire).

Study Type

Interventional

Enrollment (Actual)

8

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Belgium
    • East Flanders
      • Ghent, East Flanders, Belgium, 9000
        • Ghent University Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • 8-17y old
  • Control subjects matched by sex, age, and self reported Tanner stage.
  • All children: height and weight between P5-P95

Exclusion Criteria:

  • No daily medication use
  • No conditions other than MCADD that restrict sports participation or physiology (e.g., no heart diseases, diabetes).
  • < P5 or > P95 on the height-weight curve
  • No neuromotor developmental delay (e.g., delayed achievement of motor milestones)
  • No recent immobilization (<6 months)
  • No surgeries involving the musculoskeletal system

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: study
children aged 8-17 with Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCADD) or control will undergo CPET and high intensity exercise circuit.
Procedure: Cardiopulmonary exercise test (CPET)
Participants undergo a CPET on a stationary bike, measuring gas exchange, ECG, and other parameters. The protocol includes 3 minutes of cycling at a constant load (body weight/2 in Watts), followed by a maximal effort test with an incremental load (Ramp protocol body weight (kg) / 4 in Watts per minute).
Procedure: High-intensity circuit training
The patients will undergo a 10-minute warm-up, followed by ~30 high intensity exercise circuit.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
glucose
Time Frame: From start of exercise until 1.5 hours post-exercise.
Analysis of glucose in blood samples taken before, immediately after, and at intervals (30 minutes, 1 hour, and 1.5 hours) following high-intensity exercise.
From start of exercise until 1.5 hours post-exercise.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Cardiorespiratory response during CPET
Time Frame: During CPET (approximately 30 minutes).
Measurement of maximal oxygen uptake during the cardiopulmonary exercise test (CPET) on a stationary bike.
During CPET (approximately 30 minutes).
Safety: Incidence of adverse events during and after exercise.
Time Frame: During and up to 48 hours post-exercise.
Monitoring and recording of any symptoms, adverse events, or complications during exercise and the following 48 hours
During and up to 48 hours post-exercise.
acylcarnitines
Time Frame: From the end of the exercise circuit until 1.5 hours post-exercise.
Monitoring of acylcarnitines before and after high intensity exercise
From the end of the exercise circuit until 1.5 hours post-exercise.

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
creatine kinase
Time Frame: From the end of the exercise circuit until 1.5 hours post-exercise.
Assessment of serum creatine kinase (CK) levels before and after exercise
From the end of the exercise circuit until 1.5 hours post-exercise.
lactate
Time Frame: From the end of the exercise circuit until 1.5 hours post-exercise.
Assessment of lactate levels before and after exercise
From the end of the exercise circuit until 1.5 hours post-exercise.
Fat metabolism during recovery phase.
Time Frame: From the end of the exercise circuit until 1.5 hours post high intensity exercise.
Monitoring of substrate utilization (including fat metabolism) through measurement of RER.
From the end of the exercise circuit until 1.5 hours post high intensity exercise.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University Hospital, Ghent

Investigators

  • Principal Investigator: Patrick Verloo, MD, University Hospital, Ghent

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 20, 2025

Primary Completion (Actual)

March 19, 2026

Study Completion (Actual)

March 19, 2026

Study Registration Dates

First Submitted

January 9, 2025

First Submitted That Met QC Criteria

January 27, 2025

First Posted (Actual)

January 28, 2025

Study Record Updates

Last Update Posted (Actual)

March 23, 2026

Last Update Submitted That Met QC Criteria

March 19, 2026

Last Verified

March 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • ONZ-2023-0579

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

All anonymous data will be made available upon publication

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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