Effects of unsupervised campus HIIT on fitness and sleep in sedentary male students: a randomized controlled trial
Question
Does a partially familiarized but mostly unsupervised campus-based HIIT program improve physical fitness and sleep quality in sedentary male university students compared with no exercise?
Summary
In sedentary male university students, a 6-week campus HIIT running/walking program improved estimated aerobic fitness and balance versus a no-exercise control. Sleep quality, agility, flexibility, core endurance, and body composition did not show clear between-group improvement. Completion and intensity compliance were high among completers, and no adverse events were reported.
Methodology
- Sedentary male university students.
- 56 participants.
- Running, jogging, brisk walking, or treadmill.
- Work intervals: 1 min at 80-90% HRmax.
- Recovery: 1 min at 40-50% HRmax.
- Intensity: HRmax estimated by 208 - 0.7 x age; RPE 15-18 hard and 11-13 recovery.
- About 26 min including 3-min warm-up and 3-min cool-down.
- 3 sessions/week.
- 6 weeks.
- Parallel randomized controlled trial with assessor blinding for instrumentation outcomes.
- Estimated VO2max, Sleep quality, Balance and physical fitness, and Body composition were tracked.
Outcomes
Estimated VO2max
HIIT improved VO2max by 5.96 mL/kg/min (+19.24%) while control declined slightly.
Group-by-time beta = -6.63, 95% CI -8.77 to -4.49, p < .001, d = 1.019.
Balance
Balance improved within the HIIT group and the interaction favored HIIT, although post-intervention between-group difference was not significant.
Group-by-time beta = -23.11, 95% CI -41.16 to -5.06, p = .012.
Sleep quality
PSQI did not show a significant group-by-time effect.
Interaction p = .299.
Other fitness and body composition
No significant group-by-time effects for agility, flexibility, core endurance, or body composition.
Insights
- A 26-min, 10-round 1:1 HIIT format can be run outdoors with HR/RPE guidance.
- Fitness claims are stronger than sleep or body-composition claims for a 6-week dose.
- Remote HR review can support unsupervised fidelity.
Limitations
- Male-only university sample.
- Short 6-week intervention.
- Estimated field VO2max rather than laboratory gas analysis.
- Subjective sleep measurement and limited control for sleep confounders.
- No long-term follow-up.
Safety
- No adverse events were reported.
- Participants were screened with PAR-Q and monitored with heart-rate devices.