Clinical trial NCT03904810: Low-frequency High-Intensity Interval Training in Overweight or Obese Young Adults
Official title: The Effectiveness of Low-frequency High-Intensity Interval Training (HIIT) in Overweight or Obese Young Adults
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Overweight and Obesity
Keywords: HIIT
Exercise frequency
Exercise intensity
Lead sponsor: The University of Hong Kong
Sponsor class: OTHER
First posted: 2019-04-05
Enrollment: 103
Sex: MALE
Minimum age (years): 18
Maximum age (years): 30
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: 5 groups ×3 times factorial design
Primary purpose: TREATMENT

Brief summary: Background: The relationship between the frequency of high-intensity interval training (HIIT) and the resultant adaptations is largely unclear. Purpose: This study examined the effects of different frequencies of HIIT compared to moderate-intensity continuous training (MICT) on body composition and cardiovascular biomarkers in overweight or obese adults. Methods: This study was a randomized, controlled, single-blinded trial. Fifty-six overweight or obese men aged between 18 and 30 years were randomly assigned to no-intervention control (CON; n=14), MICT performed thrice weekly (MICT×3/wk; n=9), HIIT performed thrice weekly (HIIT×3/wk; n=14), HIIT performed twice weekly (HIIT×2/wk; n=10), and HIIT performed once weekly (HIIT×1/wk; n=9). Each HIIT session consisted of 12 × 1-min bouts at 90% heart rate reserve (HRR), interspersed with 11 × 1-min bouts at 70% HRR (HIIT×3/wk: 69 min/wk; HIIT×2/wk: 46 min/wk; HIIT×1/wk: 23 min/wk). Aerobic capacity, resting heart rate, body composition, waist circumference, blood pressure, endothelial function, fasting blood glucose and lipids, circulatory adipokines and inflammatory biomarkers were examined at baseline, after 4 weeks and 8 weeks of intervention.

Detailed description: Individuals who fulfilled the following inclusion criteria were invited to participate in the present study: 1) Chinese male; 2) aged 18-30 years; and 3) overweight or obesity, defined as BMI ≥23 kg/m2 (classification of overweight for Hong Kong adults according to Department of Health, Hong Kong SAR Government) (13). Subjects were excluded if they had: 1) chronic medical and health condition such as cardiovascular diseases, diabetes, neurological disease, musculoskeletal disorder, cancers, and autoimmune diseases; 2) hypertension (blood pressure \>140/90 mmHg); 3) contraindications to participating in physical exercise; 4) any pre-existing medical or physical issues that affected the experimental test; 5) physically active (i.e., \>3 hours of moderate-intensity exercise weekly) or 6) lean overweight population (BMI ≥23 kg/m2, but percent body fat ≤20%) according to the BMI data corresponding to bioelectrical impedance estimated percent body fat cut-off value among Hong Kong Chinese adults.

Of those who were screened, 103 Chinese young adults were eligible to participate in this study. They were provided with written and verbal information on the study protocol and the possible associated discomforts and risks followed by obtaining their written informed consent to participate in this study. The study protocol and consent form were approved by the Human Subjects Ethics Sub-Committee of The Hong Kong Polytechnic University (ethics approval reference number: HSEARS20160927005-01).

This study was a single-blind, randomized, controlled trial. Subjects were randomly assigned to 1) no-intervention control (CON), 2) MICT performed thrice weekly (MICTx3/wk), 3) HIIT performed thrice weekly (HIITx3/wk), 4) twice weekly (HIITx2/wk), and 5) once weekly (HIITx1/wk). All subjects were instructed to maintain their usual daily activities. Outcome measures including aerobic capacity, body composition, blood pressure, resting heart rate, endothelial function, arterial stiffness, fasting glucose, lipids markers, adipokine marker, and inflammatory marker were assessed at baseline, 4 weeks and 8 weeks after the intervention.

Eligibility criteria: Inclusion Criteria:

1. Chinese male
2. Aged 18-30 years
3. Overweight or obesity, defined as BMI ≥23 kg/m2 (classification of overweight for Hong Kong adults according to Department of Health, Hong Kong SAR Government)

Exclusion Criteria:

1. Chronic medical and health condition such as cardiovascular diseases, diabetes, neurological disease, musculoskeletal disorder, cancers, and autoimmune diseases
2. Hypertension (blood pressure \>140/90 mmHg)
3. Contraindications to participating in physical exercise
4. Any pre-existing medical or physical issues that affected the experimental test
5. Physically active (i.e., \>3 hours of moderate-intensity exercise weekly)
6. Lean overweight population (BMI ≥23 kg/m2, but percent body fat ≤20%) according to the BMI data corresponding to bioelectrical impedance estimated percent body fat cut-off value among Hong Kong Chinese adults.

Primary outcomes:
measure: Estimated maximal oxygen consumption
timeFrame: 8 weeks
measure: Total running distance
timeFrame: 8 weeks
measure: Total body fat percentage
timeFrame: 8 weeks
measure: Total body fat mass
timeFrame: 8 weeks
measure: Total body fat-free mass percentage
timeFrame: 8 weeks
measure: Total fat-free mass
timeFrame: 8 weeks
measure: Trunk fat mass
timeFrame: 8 weeks
measure: Body weight
timeFrame: 8 weeks
measure: Body height
timeFrame: 8 weeks
measure: Body mass index (BMI)
timeFrame: 8 weeks
measure: Waist circumference
timeFrame: 8 weeks
Secondary outcomes:
measure: Systolic blood pressure
timeFrame: 8 weeks
measure: Diastolic blood pressure
timeFrame: 8 weeks
measure: Mean arterial pressure
timeFrame: 8 weeks
measure: Resting heart rate
timeFrame: 8 weeks
measure: Endothelial function
timeFrame: 8 weeks
measure: Arterial stiffness
timeFrame: 8 weeks
measure: Serum fasting glucose
timeFrame: 8 weeks
measure: Triglycerides
timeFrame: 8 weeks
measure: High-density lipoproteins (HDL) cholesterol
timeFrame: 8 weeks
measure: Low-density lipoprotein (LDL) cholesterol
timeFrame: 8 weeks
measure: Interleukin 6
timeFrame: 8 weeks
measure: Tumor necrosis factor alpha
timeFrame: 8 weeks
measure: C-reactive protein
timeFrame: 8 weeks
measure: Adiponectin
timeFrame: 8 weeks
measure: Intercellular adhesion molecule-1
timeFrame: 8 weeks
measure: Vascular cell adhesion molecule-1
timeFrame: 8 weeks
Other outcomes:
Locations:
city: Hong Kong
country: Hong Kong
facility: LKS Faculty of Medicine
Study officials:
References: