The Prevalence of Responders and Non-Responders for Body Composition, Resting Blood Pressure, Musculoskeletal, and Cardiorespiratory Fitness after Ten Weeks of School-Based High-Intensity Interval Training in Adolescents
Question
What proportion of adolescents respond or do not respond in body composition, blood pressure, musculoskeletal fitness, and cardiorespiratory fitness after a 10-week school-based HIIT program, and are responses related to sex, BMI, or maturation?
Summary
A 10-week school PE Tabata program found that adolescents varied substantially in who improved after once-weekly HIIT. More students were classified as responders than non-responders for body fat percentage, skeletal muscle mass, blood pressure, cardiorespiratory fitness, and abdominal strength, but many did not improve in hand strength or vertical jump.
Methodology
- Healthy mid-adolescent boys and girls in secondary-school PE.
- 73 participants.
- Bodyweight Tabata-style intervals embedded in PE lessons.
- Work intervals: Each Tabata block used 8 cycles of 20 seconds of maximal-intensity exercise followed by 10 seconds of active rest.
- Recovery: Each Tabata block used 8 cycles of 20 seconds of maximal-intensity exercise followed by 10 seconds of active rest.
- Intensity: Target high intensity was 75-80% HRmax, with HRmax estimated as 208 - 0.7 x age. Heart rate was monitored in an initial lesson, with mean HR about 155.8 +/- 18.2 bpm.
- Each standard 45-minute PE lesson included a 10-minute warm-up followed by a 14-minute Tabata aerobic protocol made up of three 4-minute Tabata blocks.
- 1 session per week.
- 10 weeks.
- Responder/non-responder analysis of experimental participants from a school-based HIIT project.
- Body composition, Resting blood pressure, Cardiorespiratory fitness, and Musculoskeletal and motor fitness were tracked.
Outcomes
Body composition, fitness, and blood pressure
The intervention was associated with significant effects for body fat mass, fitness index, systolic blood pressure, and sex-dependent abdominal strength and flexibility outcomes.
Responder prevalence for body composition and fitness
More responders than non-responders were observed for body fat percentage, skeletal muscle mass, systolic blood pressure, diastolic blood pressure, fitness index, and abdominal strength.
Hand strength and vertical jump response
More non-responders than responders were observed for hand strength and vertical jump.
Sex-related response patterns
Sex was associated with abdominal-strength response and was close to significance for skeletal-muscle-mass response; boys were more likely to be skeletal-muscle-mass responders and girls more likely to be abdominal-strength responders.
Maturation-related response patterns
Maturation status was related to skeletal-muscle-mass and systolic-blood-pressure response, while BMI was not clearly associated with response status.
Insights
- Even a low-frequency, once-weekly Tabata block in PE can produce measurable improvements in some adolescents, but response is heterogeneous.
- Responder analysis may be useful for HIIT personalization because average effects can hide substantial non-response in strength, power, or motor outcomes.
- Sex and maturation may matter when interpreting adolescent HIIT outcomes, particularly for body composition and abdominal strength.
- A 14-minute bodyweight Tabata block is a practical school-friendly format.
Limitations
- The paper's main responder analysis included only experimental participants, so causal interpretation is weaker than a full randomized comparison.
- HIIT was performed only once weekly for 10 weeks.
- The sample excluded prepubertal and peripubertal adolescents.
- Nutrition was not controlled.
- Body composition was not measured with DXA.
- Cardiorespiratory fitness was estimated by the Harvard Step Test rather than direct VO2max testing.
Safety
- No adverse-event reporting was identified in the extracted article text.