ISRCTN - ISRCTN66508384: High intensity exercise may be an efficient startegy for obesity management

Plain English Summary

Background and study aims
Sedentary behaviour (taking part in less than an hour a week of physical activity) is associated with an increased risk of heart disease, type 2 diabetes and some forms of cancer, as well as poorer mental wellbeing. It is a growing problem, and is thought to contribute significantly to the high levels of obesity worldwide. For many people, not having enough time to exercise is often used as an excuse for sedentary behaviour. There is therefore a growing amount of research looking into exercise strategies that involve a shorter time commitment but still provide health benefits. A recent study showed that very brief high-intensity exercise in the form of sprinting, made up of sprints lasting for 6-10 seconds, was found to be motivating and tolerable for participants and can even help to burn fat. The aim of this study is to find out whether taking part in high intensity exercise for six weeks can help improve blood sugar control, BMI and physical fitness in young obese adults.

Who can participate?
Obese adults aged between 18 and 30 who have a sedentary lifestyle.

What does the study involve?
Participants are randomly allocated to one of two groups. Those in the first group take part in the training program, which consists of three training sessions per week for six weeks (a total of 18). Those in the second group do not take part in any training during the 6 weeks and are also asked to consume their normal diet and to maintain their typically sedentary behavior during the training period. At the start of the study, after the program ends and then 24, 72 hours and two weeks after the final session, participants in both groups complete a number of tests in order to assess how well their bodies are able to process sugar, physical characteristics (such as weight) and how physically fit they are.

What are the possible benefits and risks of participating?
Participants will benefit from being informed about their health and fitness levels and could also take advantage of training program to improve their physical fitness and health. There are no direct risks to participants taking part in this study.

Where is the study run from?
University of Moncton (Canada)

When is the study starting and how long is it expected to run for?
January 2014 to June 2014

Who is funding the study?
University of Moncton (Canada)

Who is the main contact?
Dr Jabbour Georges
georges.jabbour@umoncton.ca

Trial website

Contact information

Type

Scientific

Primary contact

Dr Jabbour Georges

ORCID ID

Contact details

School of Kinesiology and Leisure
Faculty of Health Sciences and Community Services
Université de Moncton
Moncton
E1A 3E9
Canada
+1 506 858 3757
georges.jabbour@umoncton.ca

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

N/A

Study information

Scientific title

Effect of supramaximal exercise training on performance variables and metabolic changes in obese adults

Acronym

Study hypothesis

The aim of this study is to evaluate the effects of six weeks of supramaximal exercise training (SET) and determine its effects on blood glucose control and insulin resistance, BMI and fitness.

Ethics approval

University’s Human Research Ethics Committee (UHRC) of the University of Moncton, 03/12/2013, ref: 1314-020

Study design

Single-center randomised controlled trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Other

Trial type

Treatment

Patient information sheet

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

Condition

Obesity

Intervention

At the start of the study, participants undergo two sessions of preliminary testing after an overnight fast to determine athropometric measurements, phsyiological measures (lung capacity and blood pressure) and metabolic testing.

Once the participants completed preliminary testing, they complete a total of 18 training sessions (three sessions per week for six weeks). Each of the prescribed sessions begins with a 5-minute warm-up of continuous cycling at moderate intensity (40% of their individual VO2peak power) followed by 6 repetitions of SET intervals with 2 minutes of passive recovery between each repetition. Each SET repetition lasts for six seconds, and the participants are asked to pedal at maximal velocity against the resistance determined during day three. The total duration of each session is approximately 15 minutes. The training sessions are conducted under the supervision of a member of the research team, and velocities (in RPM) were recorded for each second of the bout to ensure that fixed velocities remained constant.

Post-intervention metabolic and blood pressure measurements are conducted 24-hours, 72-hours and two-weeks after the final training session to obtain information on the potential lasting effects of SET. The post-intervention anthropometric assessment is performed 24 hours after the final SET session, and the post-intervention exercise tests are performed 72 hours after the final SET session.

Intervention type

Other

Phase

Drug names

Primary outcome measure

Insulin resistance (HOMA-IR) is determined by measuring blood glucose and insulin concentrations at baseline, 24 hours, 72 hours and 2 weeks post-intervention.

Secondary outcome measures

1. BMI is calculated as the ratio of mass (kg) to height squared (m2) at baseline and 24 hours post-intervention
2. Maximal oxygen consumption (VO2max) is measured using an incremental maximal test at baseline and 72 hours post-intervention
3. Maximal power is measured using a force-velocity test on a cycle ergometer at baseline and 72 hours post-intervention
4. Blood pressure is measured using an automated blood pressure monitor at baseline, 72 hours and 2 weeks post-intervention

Overall trial start date

10/01/2014

Overall trial end date

01/06/2014

Reason abandoned (if study stopped)

Eligibility

Participant inclusion criteria

1. Aged between 18 an 30 years
2. Obesity (BMI >30 kg/m2)
3. Sedentary (<1 h/week of structured exercise)

Participant type

Healthy volunteer

Age group

Adult

Gender

Both

Target number of participants

24

Total final enrolment

24

Participant exclusion criteria

History of cardiovascular or chronic health problems, drug consumption, or smoking.

Recruitment start date

01/02/2014

Recruitment end date

25/02/2014

Locations

Countries of recruitment

Canada

Trial participating centre

University of Moncton
School of Kinesiology and Leisure Faculty of Health Sciences and Community Services
Moncton
E1A 3E9
Canada

Sponsor information

Organisation

University of Moncton (Université de Moncton)

Sponsor type

University/education

Website

Funders

Funder type