Optimal Frequency of High-Intensity Interval Training for Centrally Obese Adults

The aim of this study is to examine the therapeutic effectiveness of two different exercise frequencies of high-intensity interval training (HIIT; once versus thrice weekly, with matched weekly exercise volume) on improving cardiometabolic risk factors in centrally obese adults.

Study Overview

• Status: Recruiting
• Conditions: Obesity
• Intervention / Treatment: Behavioral: Once-Weekly HIIT; Behavioral: Thrice-Weekly HIIT; Other: Usual Care

Detailed Description

HIIT is an emerging, popular, promising, cost-effective, and time-efficient exercise modality for managing obesity. Although lower-frequency HIIT is favorable for intervention adherence, the optimal exercise frequency of HIIT for alleviating obesity is unknown.

This study is a three-arm randomized controlled trial. Centrally obese adults will be randomly allocated to three groups: the usual care control, once and thrice-weekly HIIT groups. Led by research personnel, the usual care group will receive obesity-related health education. Led by athletic coaches, the HIIT intervention groups will receive 16 weeks of once or thrice weekly HIIT (with matched weekly exercise volume). Outcome measures of this study will be examined at baseline, 4 months (post-intervention), and 8 months (follow-up), by assessors blinded to group allocation.

• Study Type: Interventional
• Enrollment (Estimated): 315
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Parco M. Siu, PhD; Phone Number: +852 2831 5262; Email: pmsiu@hku.hk

Study Locations

• Hong Kong
  • Hong Kong, Hong Kong
    • Recruiting
    • LKS Faculty of Medicine
    • Sub-Investigator: Joshua Bernal, BSc
    • Contact: Chit-Kay Leung, BSc; Phone Number: (852) 28315291; Email: lchitkay@connect.hku.hk
    • Sub-Investigator: Chit-Kay Leung, BSc

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Aged above 18 years
• Ethnic Chinese
• Overweight (BMI ≥23 for Asian)
• Centrally obese according to IDF and NCEP with Asian-specific cut-off (waist circumference ≥90 cm for males; ≥80 cm for females)
• Males and females

Exclusion Criteria:

• Medical and somatic conditions that prevent brisk walking
• Chronic diseases affecting mobility and motor function (e.g., neurological disease, musculoskeletal disorder, spinal cord injury, autoimmune, arthritis, Parkinson's Disease)
• Chronic diseases affecting cardiorespiratory and metabolic health (e.g., cancers, cardio-/cerebrovascular diseases, heart disease, diabetes mellitus, pneumonia, chronic pulmonary diseases, nephritis, nephrosis)
• Signs of cardiac arrhythmia indicated by aberrant electrocardiography during incremental VO2max test
• Regular moderate-to-vigorous intensity exercise (≥150 min weekly) in the past 3 months, as screened by a specially designed questionnaire
• Daily smoking habit
• Excess alcohol consumption (daily ≥30g for men, ≥20g for women) in the past six months
• Claustrophobia
• Surgery, therapy or medication for obesity or weight loss in the past six months (e.g., gastric bypass, gastric band, sleeve gastrectomy, gastric reduction duodenal switch, and dietitian-prescribed dietary program)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Once-Weekly HIIT; Once-weekly HIIT for 16 weeks, led by certified athletic coaches	Behavioral: Once-Weekly HIIT; Participants in this group will receive a 16-week intervention of HIIT once weekly supervised by certified athletic coaches. Participants will perform four 4-minute intervals at 85%-95% peak heart rate with a 3-minute active recovery between each 4-minute interval. Participants will repeat the 25-minute HIIT bout three times with 30-60 minutes break in between each 25-minute HIIT bout. Health information provided to the usual care control group will be made available to the participants in the HIIT groups.
Experimental: Thrice-Weekly HIIT; Thrice-weekly HIIT for 16 weeks, led by certified athletic coaches	Behavioral: Thrice-Weekly HIIT; Participants in this group will receive a 16-week intervention of HIIT thrice weekly supervised by certified athletic coaches. Participants will perform four 4-minute intervals at 85%-95% peak heart rate with a 3-minute active recovery between each 4-minute interval. Health information provided to the usual care control group will be made available to the participants in the HIIT groups.
Other: Usual Care; Bi-weekly health education, led by research personnel	Other: Usual Care; Participants in the usual care control group will receive health education delivered by research personnel. This program will consist of eight two-hour bi-weekly sessions covering major health issues relating to obesity including causes, prevalence, epidemiology, associated diseases, healthy diet, caloric restriction advice, physical activity, stress management, adequate sleep, as well as lifestyle counseling/consultation and goal-setting/record-keeping strategies for behavioral changes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Body Fat	Total body fat mass will be assessed using dual-energy X-ray absorptiometry (DXA)	Baseline and 4 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Body Fat	Total body fat mass will be assessed using dual-energy X-ray absorptiometry (DXA)	Baseline and 8 months
Change in Abdominal Visceral Fat	Abdominal visceral fat will be assessed using magnetic resonance imaging (MRI)	Baseline and 4 and 8 months
Change in Abdominal Subcutaneous Fat	Abdominal subcutaneous fat will be assessed using magnetic resonance imaging (MRI)	Baseline and 4 and 8 months
Change in Body Mass Index	Weight and height will be assessed using a calibrated electronic digital weighing scale and stadiometer respectively	Baseline and 4 and 8 months
Change in Waist Circumference	Waist circumference will be assessed using an inelastic measuring tape to the nearest 0.1cm on bare skin	Baseline and 4 and 8 months
Change in Systolic Blood Pressure	Resting systolic blood pressure will be assessed	Baseline and 4 and 8 months
Change in Diastolic Blood Pressure	Resting diastolic blood pressure will be assessed	Baseline and 4 and 8 months
Change in Fasting Glucose	Fasting glucose will be analyzed from venous blood by an accredited medical laboratory	Baseline and 4 and 8 months
Change in Fasting Triglycerides	Fasting triglycerides will be analyzed from venous blood by an accredited medical laboratory	Baseline and 4 and 8 months
Change in Fasting Low Density Lipoprotein Cholesterol (LDL-C)	Fasting LDL-C will be analyzed from venous blood by an accredited medical laboratory	Baseline and 4 and 8 months
Change in Fasting High Density Lipoprotein Cholesterol (HDL-C)	Fasting HDL-C will be analyzed from venous blood by an accredited medical laboratory	Baseline and 4 and 8 months
Change in Fasting Total Cholesterol	Fasting total cholesterol will be analyzed from venous blood by an accredited medical laboratory	Baseline and 4 and 8 months
Change in Proportion of Metabolic Syndrome Diagnosis	Metabolic syndrome diagnosis will be evaluated with waist circumference, triglycerides, HDL-C, blood pressure, and fasting glucose	Baseline and 4 and 8 months
Number of Adverse Events	Adverse events related or unrelated to training will be assessed	Baseline and 4 and 8 months
Change in Organ Fat	Organ fat will be assessed using magnetic resonance imaging (MRI)	Baseline and 4 and 8 months
Change in SF-12 Physical Component Summary Score	Physical health-related quality of life will be assessed using the Physical Component Summary Score of the 12-Item Short-Form Health Survey (SF-12)	Baseline and 4 and 8 months
Change in SF-12 Mental Component Summary Score	Mental health-related quality of life will be assessed using the Mental Component Summary Score of the 12-Item Short-Form Health Survey (SF-12)	Baseline and 4 and 8 months
Change in HADS-D Score	HADS-D score will be assessed using the Depression subscale of the Hospital Anxiety and Depression Scale (HADS-D)	Baseline and 4 and 8 months
Change in PHQ-9 Score	PHQ-9 score will be assessed using the Patient Health Questionnaire-9 (PHQ-9)	Baseline and 4 and 8 months
Change in HADS-A Score	HADS-A score will be assessed using the Anxiety subscale of the Hospital Anxiety and Depression Scale (HADS-A)	Baseline and 4 and 8 months
Change in GAD-7 Score	GAD-7 score will be assessed using the General Anxiety Disorder-7 (GAD-7) Questionnaire	Baseline and 4 and 8 months

Collaborators and Investigators

• Sponsor: The University of Hong Kong
• Investigators: Principal Investigator: Parco M. Siu, PhD, The University of Hong Kong

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2021
• Primary Completion (Estimated): June 30, 2024
• Study Completion (Estimated): December 31, 2024

Study Registration Dates

• First Submitted: May 10, 2021
• First Submitted That Met QC Criteria: May 10, 2021
• First Posted (Actual): May 14, 2021

Study Record Updates

• Last Update Posted (Estimated): December 1, 2023
• Last Update Submitted That Met QC Criteria: November 29, 2023
• Last Verified: November 1, 2023

More Information

Terms related to this study

• Keywords: Obesity; Adults; Metabolic Syndrome; Aerobic Exercise; High-Intensity Interval Training; Central Obesity
• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Overweight; Body Weight; Obesity
• Other Study ID Numbers: 1v3HIIT

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The data of individual participants that underlie the results reported in this trial, after de-identification including text, tables, figures, and appendices, as well as study protocol and statistical analysis plan, will be shared after 3 months of study publication. Data will be shared with researchers who provide a methodologically sound proposal for academic purposes. Proposals should be directed to pmsiu@hku.hk to gain access and for data request, a data-access agreement needs to be signed.
• IPD Sharing Time Frame: Beginning 3 months and ending 3 years following the publication of the article.
• IPD Sharing Access Criteria: Data will be shared with researchers who provide a methodologically sound proposal for academic purposes. Proposals should be directed to pmsiu@hku.hk to gain access and for data request, a data-access agreement needs to be signed.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No