# Effect of Novel, School-Based High-Intensity Interval Training (HIT) on Cardiometabolic Health in Adolescents: Project FFAB (Fun Fast Activity Blasts) - An Exploratory Controlled Before-And-After Trial

PMID: 27486660
Journal: PLOS ONE
Published: 2016
Authors: Weston KL, Azevedo LB, Bock S, Weston M, George KP, Batterham AM

## Question

What is the effect of a school-based multi-activity low-volume HIT intervention on cardiometabolic risk factors and physical activity in adolescents?

## Summary

Project FFAB tested a school-based, multi-activity low-volume HIT program in 14-year-old adolescents. The non-randomized intervention produced likely beneficial effects for triglycerides, waist circumference, and daily MVPA, and a possibly beneficial effect for shuttle-run performance, with 77% attendance among completers.

## Population

- Year 9 adolescents from four secondary schools in Northeast England.
- Sample size: 101
- Age: 14.1 +/- 0.3 years
- Sex: 62 males overall; control 30/30 male/female, intervention 33/8 male/female.
- Fitness level: General school sample.
- Health status: Mostly normal weight, with 22% overweight/obese.

## Methodology

- Exploratory controlled before-and-after clustered non-randomized trial.
- 10-week intervention delivered across 13 calendar weeks because of school holidays
- Four secondary schools in Northeast England.
- Controlled study design.

## Protocol

- Project FFAB low-volume school HIT.
- Modality: Basketball, boxing, dance, and soccer drills.
- Work intervals: 45 s.
- Recovery: 90 s.
- Sets or repetitions: 4-7 repetitions.
- Intensity: Maximal effort; target peak HR >=90% HRmax.
- Session duration: About 15-20 min including warm-up/cooldown.
- Frequency: 3 sessions/week.
- Program length: 10 weeks.
- Progression: Repetitions increased from 4 to 7 and activities changed weekly.
- Usual PE curriculum.
- Modality: Normal school PE.
- Frequency: Usual PE curriculum.
- Program length: 10-week intervention period.

## Outcomes

### Triglycerides
Status: improved
Intervention had a likely beneficial effect on triglycerides compared with control.

-26%, 90% CI -46% to 0%.

### Waist circumference
Status: improved
Waist circumference improved in intervention participants compared with controls.

-3.9 cm, 90% CI -6.1 to -1.6.

### Daily MVPA
Status: improved
Daily MVPA showed a likely beneficial increase.

+16 min/day, 90% CI -5 to 38.

### 20 m shuttle-run
Status: improved
Shuttle-run performance had a possibly beneficial effect.

+5 shuttles, 90% CI -1 to 11.

### Other cardiometabolic/body-composition outcomes
Status: no clear change
No clinically substantial effects were reported for BP, TC, HDL, glucose, hsCRP, cIMT, body fat, SMM, weight, BMI, or DBP.

## Practical Insights

- Youth HIT can be built from sports and dance drills rather than repetitive running.
- School programs need intensity monitoring alternatives when HR equipment is limited.
- Low-volume school sessions can be inserted into PE/lunch/after-school windows.

## Limitations

- Non-randomized school allocation
- Only four schools
- Exploratory design
- Intervention sex imbalance
- Incomplete HR monitoring
- No long-term follow-up

## Safety And Adherence

- Two male participants sustained injuries unrelated to the study and stopped completing HIT sessions.
- No study-related injury signal was reported.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/27486660/) (pubmed)
- [DOI](https://doi.org/10.1371/journal.pone.0159116) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4972319/) (full text)

## Agent Guidance

Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.