The Irisin and Metabolic Exercise Training Study

Obesity Clinical Trial

— iMET  

Official title:

The Irisin and Metabolic Exercise Training Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03514238
• Other study ID #: University of New Brunswick
• Status: Completed
• Phase: N/A
• Start date: September 1, 2017
• Est. completion date: November 1, 2019

Study information

• Verified date: November 2020
• Source: University of New Brunswick
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

It has been established that greater amounts of vigorous intensity physical activity lead to improved health outcomes. Interestingly, the response of biologically active substances, called myokines, differs according to exercise intensity. As such, the current study aims to compare the difference in the response to irisin according to different exercise intensities in both normal weight subjects and individuals living with obesity. This study will compare continuous moderate intensity physical activity to high intensity physical activity against a control condition. Furthermore, this study will determine whether differences in exercise intensity are associated with better insulin sensitivity.

Description:

Although exercise is recognized as a cornerstone in the management of obesity and diabetes, previous research has shown substantial inter-individual variability following an exercise intervention. As of now, the mechanisms underlying the cardio-metabolic response to exercise have not been fully elucidated. When accounting for genetic factors, only 20-30% of the response is explained, which indicates that other factors must contribute to this exercise-related cardio-metabolic response. Exercise stimulates the release of myokines, which have been shown to play a critical role in health. However, the contribution of these myokines to the cardio-metabolic response is unknown. Furthermore, the regulation of myokines according to different exercise stimuli (i.e., exercise intensity) is unclear. It is suggested that altering specific exercise parameters can reduce the variability in the response and increase the proportion of participants who obtain the expected physiological adaptations.

The purpose of this project is to: 1) determine whether high intensity interval training (HIIT) generates a greater secretion of irisin compared to moderate (MOD) aerobic exercise in individuals living with obesity and in those with a normal weight; 2) investigate whether the increase in irisin during exercise is associated with insulin sensitivity in individuals living with obesity and in those with normal weight; and 3) determine whether differences exist between groups.

Methods: The investigators will use a randomized controlled crossover design to perform this study in which 40 participants (aged 19-50) will be recruited into two groups (n = 20 obese, n = 20 normal weight). Each group will be randomized into three conditions: 1) an acute bout of MOD aerobic exercise: 35 minutes of cycling at 50% of heart rate reserve (HRR), 2) an acute bout of HIIT aerobic exercise: cycling at 50% of HRR for 5 minutes followed by 2 minutes of cycling at 85-90% of HRR consecutively for a total of 35 minutes, and 3) a control condition: blood draws matched for exercise time will be taken while the participant remains seated. The primary outcome measure will be insulin sensitivity using the Matsuda Index. The primary exposure variable will be the acute secretion of irisin during exercise.

Study hypothesis: It is hypothesized that: 1) an acute bout of HIIT aerobic exercise will generate a greater plasma irisin secretion compared an acute bout of continuous MOD aerobic exercise; 2) increased irisin will be positively associated with greater insulin sensitivity; and 3) differences will be observed between individuals living with obesity and those with a normal weight.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: November 1, 2019
• Est. primary completion date: November 1, 2019
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 19 Years to 50 Years

Eligibility

Inclusion Criteria:

• Obesity (=30 kg/m2);

• Physical inactivity (must not reach Canadian Physical Activity Guidelines);

• At risk for Type 2 diabetes;

• Adult (aged 19-50).

Exclusion Criteria:

• Individuals with Type 2 diabetes;

• Chronic conditions or injuries that would impact exercise;

• Regular exercise training.

Related Conditions & MeSH terms

• Obesity

Intervention

Behavioral:
• High Intensity Interval Aerobic Exercise (HIIT)
Cycling at 50-55% heart rate reserve for 5 minutes followed by 2 minutes of cycling at 85-90% heart rate reserve consecutively for a total of 35 minutes. Blood draws will occur at 6 different time points during exercise (0min, 7min, 14min, 21min, 28min, 35min).
• Continuous Moderate Aerobic Exercise (MOD)
35 minutes of cycling at 50-55% heart rate reserve. Blood draws will occur at 6 different time points during exercise (0min, 7min, 14min, 21min, 28min, 35min).
• Control Sitting Condition (C)
Blood draws matched for exercise time will be taken while participant remains seated for 35 minutes (0min, 7min, 14min, 21min, 28min, 35min).

Locations

Country	Name	City	State
Canada	University of New Brunswick - Kinesiology	Fredericton	New Brunswick

Sponsors (2)

Lead Sponsor	Collaborator
University of New Brunswick	New Brunswick Health Research Foundation

Country where clinical trial is conducted

Canada, 

References & Publications (2)

Blizzard LeBlanc DR, Rioux BV, Pelech C, Moffatt TL, Kimber DE, Duhamel TA, Dolinsky VW, McGavock JM, Sénéchal M. Exercise-induced irisin release as a determinant of the metabolic response to exercise training in obese youth: the EXIT trial. Physiol Rep. 2017 Dec;5(23). doi: 10.14814/phy2.13539. — View Citation

Fox J, Rioux BV, Goulet EDB, Johanssen NM, Swift DL, Bouchard DR, Loewen H, Sénéchal M. Effect of an acute exercise bout on immediate post-exercise irisin concentration in adults: A meta-analysis. Scand J Med Sci Sports. 2018 Jan;28(1):16-28. doi: 10.1111/sms.12904. Epub 2017 May 24. Review. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Insulin Sensitivity	Insulin sensitivity using the Matsuda Index.	Baseline