Condition category
Nutritional, Metabolic, Endocrine
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Fatty acid oxidation is an important source of energy during prolonged fasting. Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is the most common inborn error of fatty acid oxidation. Patients’ experience may vary, ranging from sudden infant death to remaining without any symptoms throughout life. The reason for this has not been fully understood. Treatment includes prevention of prolonged fasting and an emergency regimen during catabolic stress (breakdown of nutrients). Patients also have difficulty in exercising continuously. During moderate-intensity exercise, energy supply is met by fatty acid oxidation of the fat stored in muscle cells. In this study we aim to analyse the effect of MCAD deficiency on exercise tolerance.

Who can participate?
Adult patients with MCAD deficiency can participate in this study.

What does the study involve?
All patients are invited to take part in two sessions of exercise on a bicycle ergometer. Blood samples will be drawn from a thin tube that will be inserted into the vein. Participants will be asked to refrain from food intake three hours before both study sessions. A food diary will be kept for 7 days prior to session 2.

What are the possible benefits and risks of participating?
No side effects of this study are expected, as the measurements are non-invasive. You may be hesitant towards the small space in the MRI scanner, but there will be sufficient time to get acquainted with the small space. Blood samples will be taken once and are without risk.

Where is the study run from?
Session 1 takes place at the paediatric test ward at the University Medical Centre Groningen (Netherlands). Session 2 takes place at the Neuroimaging Centre (NIC), Groningen (Netherlands).

When is study starting and how long is it expected to run for?
The study started in October 2012 and ended in December 2013.

Who is funding the study?
The study is funded by RVVZ Foundation, Netherlands.

Who is the main contact?
Prof. G.P.A. Smit

Trial website

Contact information



Primary contact

Prof G. Peter A. Smit


Contact details

Hanzeplein 1
9700 RB

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

In vivo analysis by 1H- and 31P-MRS of the effect of moderate-intensity exercise on intramyocellular lipid content and mitochondrial function in patients with MCAD deficiency


Study hypothesis

Patients with MCAD deficiency are unable to oxidize sufficient intramyocellular fatty acids during exercise to meet the energy demands, resulting in intramuscular energy deficiency and muscle complaints.

Ethics approval

Medical Ethics Committee of the University Medical Centre Groningen, 01/10/2012, ref: METc 2012/262

Study design

Interventional case-control study

Primary study design


Secondary study design

Case-control study

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


MCAD deficiency


All participants undergo the two described study sessions as follows.
Incremental test on bicycle ergometer for determination of VO2max (session 1). Exercise for 80 minutes on bicycle ergometer and MRS analyses before, during and after exercise (session 2). Exercise during MRS will be performed on an MR-compatible bicycle. Venipuncture during session 2 (four small blood samples will be drawn from a cannula that will be inserted upon venipuncture for analysis of metabolites that play a role in muscle metabolism). For matters of standardization, participants will be asked to abstain from food intake three hours before both study sessions. A food diary will be kept for 7 days prior to session 2.

Intervention type



Not Applicable

Drug names

Primary outcome measures

Intramyocellular lipid content is measured by means of 1H-MRS. We obtain spectra at baseline and after prolonged exercise, and have professional help for analysis of the spectra.

Secondary outcome measures

Concentrations of phosphocreatine, adenosine 5’-triphosphate, inorganic phosphate, and intracellular pH.
These are measured by 31P-MRS. We obtain spectra before, during, and after exercise, and have professional help for analysis of the spectra.

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

Patient group: Patients with MCAD deficiency who are over 18 years of age
Control group: Healthy volunteers over 18 years of age, matched for age and gender to the patient group

Participant type

Healthy volunteer

Age group




Target number of participants


Participant exclusion criteria

1. Disease other than MCAD deficiency
2. Contra-indications for MR analysis (e.g. the presence of metals in the body)

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Hanzeplein 1
9700 RB

Sponsor information


University Medical Centre Groningen (Netherlands)

Sponsor details

Hanzeplein 1
9700 RB

Sponsor type

Hospital/treatment centre



Funder type

Research organisation

Funder name

RVVZ Foundation (Reserves Voormalige VrijwilligeZiekenfonds-verzekeringen) (Netherlands)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes