A Comparative Study of Indoor and Outdoor High-Intensity Interval Training (HIIT) on Health-Related Physical Fitness and Sleep Quality in University Students

Status

Active, not recruiting

Phases

Phase 1

Study type

Interventional

Source

TCTR

Registry ID

TCTR20260505003

Enrollment

Registered

2026-05-05

Start date

2025-11-10

Completion date

Unknown

Last updated

2026-08-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Non-exercise lifestyle Poor sleep quality Cardiorespiratory fitness Physical inactivity High-Intensity Interval Training Exercise Sleep Quality Physical Fitness Environment University Students Cardiorespiratory Endurance Body Composition

Interventions

Participants perform a 30-minute HIIT session 3 days per week for 8 weeks at an outdoor facility with a target temperature of 34.0 plus or minus 1.0 Celsius. Each session includes a 5-minute warm-up,

Experimental Behavioral,Active Comparator Behavioral

Outdoor High-Intensity Interval Training (HOD),Indoor High-Intensity Interval Training (HID)

Eligibility

Sex/Gender

All

Age

18 Years to 25 Years

Inclusion criteria

Inclusion criteria: 1. University students aged 18 to 25 years 2. Sedentary lifestyle with less than 150 minutes of moderate physical activity per week for more than 6 months 3. Body Mass Index (BMI) less than 30 kg/m2 4. Cleared for exercise via the Physical Activity Readiness Questionnaire (PAR-Q+)

Exclusion criteria

Exclusion criteria: 1. Clinical history of cardiovascular, respiratory, or metabolic disease 2. Musculoskeletal injuries limiting high-intensity exercise 3. Resting blood pressure greater than 135/90 mmHg 4. Use of supplements or medications affecting metabolism or sleep

Design outcomes

Primary

Measure	Time frame
Cardiorespiratory Fitness (VO2max) Baseline (Week 0) and Post-intervention (after Week 8) Estimated via the Astrand-Ryhming Cycle Ergometer Test (corrected for age),Sleep Quality Baseline (Week 0) and Post-intervention (after Week 8) Assessed using the Thai version of the Pittsburgh Sleep Quality Index (PSQI)	—

Secondary

Measure	Time frame
Body Composition Baseline (Week 0) and Post-intervention (after Week 8) Measured via Bioelectrical Impedance Analysis (BIA),Pulmonary Function Baseline (Week 0) and Post-intervention (after Week 8) Measured via digital spirometer (FVC, FEV1, FEV1/FVC, and MVV) following ATS/ERS standards,Muscle Strength and Endurance Baseline (Week 0) and Post-intervention (after Week 8) Measured via Leg Dynamometer for leg strength, 60-second Push-Up Test for upper body strength, and 60-second Sit-Up Test for abdominal strength. ,Flexibility Baseline (Week 0) and Post-intervention (after Week 8) Assessed using the Sit and Reach Test for lower back and hamstring flexibility, and the Back Scratch Test for shoulder and scapular flexibility. Values are recorded in centimeters.	—

Measure

Time frame

Body Composition Baseline (Week 0) and Post-intervention (after Week 8) Measured via Bioelectrical Impedance Analysis (BIA),Pulmonary Function Baseline (Week 0) and Post-intervention (after Week 8) Measured via digital spirometer (FVC, FEV1, FEV1/FVC, and MVV) following ATS/ERS standards,Muscle Strength and Endurance Baseline (Week 0) and Post-intervention (after Week 8) Measured via Leg Dynamometer for leg strength, 60-second Push-Up Test for upper body strength, and 60-second Sit-Up Test for abdominal strength. ,Flexibility Baseline (Week 0) and Post-intervention (after Week 8) Assessed using the Sit and Reach Test for lower back and hamstring flexibility, and the Back Scratch Test for shoulder and scapular flexibility. Values are recorded in centimeters.

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Countries

Thailand

Contacts

Public ContactBulin Jirapongsatorn

Walailak University

oatbulinji@gmail.com075677417

Outcome results

None listed

Source: TCTR (via WHO ICTRP) · Data processed: Aug 10, 2026