High-Intensity Interval Training for Overweight Adolescents: Program Acceptance of a Media Supported Intervention and Changes in Body Composition
Question
Does media support improve attendance and acceptance for a 6-month HIIT program in overweight adolescents, and are body composition markers changed?
Summary
This small feasibility trial tested whether text/email/website support improved attendance for an outdoor HIIT program in overweight adolescents. Media support did not significantly improve attendance, overall attendance fell during school vacation, and body-fat and waist-to-height ratio improved modestly across participants.
Methodology
- Overweight adolescents in Leipzig, Germany.
- 28 participants.
- Outdoor HIIT with running, Tabata, sprinting, and low-volume strength exercises.
- Work intervals: Examples: 20 s Tabata or 60 s sprint.
- Recovery: Examples: 10 s active recovery or 75 s rest/active recovery.
- Intensity: 80-95% HRmax during work intervals.
- 60 min.
- 2 sessions/week.
- 6 months.
- Randomized controlled feasibility trial with both groups receiving HIIT and one group receiving media support.
- Attendance, Program acceptance, BMI-SDS, and Waist-to-height ratio were tracked.
Outcomes
Attendance
Media support increased mean attendance numerically but not significantly.
Control 13.6 +/- 10.7 sessions vs media 19.5 +/- 12.1; p=0.19; Wilcoxon p=0.165.
Attendance over time
Attendance was 65-75% early and fell to about 15% in the last 3 months, coinciding with summer vacation.
Survival log-rank p=0.48 between groups.
Program acceptance
Participants rated the program favorably, but ratings did not correlate with attendance.
Overall rating 2.33 +/- 1.37; attendance/evaluation r=0.02 p=0.942.
Body composition
Waist-to-height ratio and estimated body fat decreased, while BMI-SDS did not significantly change.
WHtR -0.013 p=0.023; body fat -2.0 percentage points p=0.011; BMI-SDS change p=0.49.
Insights
- Adolescent HIIT adherence can collapse when school routines change.
- Digital reminders may help some users but should not be treated as sufficient adherence support.
- Favorable ratings do not guarantee attendance.
Limitations
- Small underpowered feasibility sample
- Both groups shared same exercise sessions
- Summer vacation disrupted attendance
- No non-exercise control
- Self-report/questionnaire completeness issues
Safety
- No adverse events or injuries were reported in the the paper.
- Serious orthopedic impairment and pregnancy were exclusion criteria.