PMID 36143083

Research
All papers

Integrating High-Intensity Interval Training into a School Setting Improve Body Composition, Cardiorespiratory Fitness and Physical Activity in Children with Obesity: A Randomized Controlled Trial

Cao M, Tang Y, Zou Y

Question

Does integrating running HIIT into school physical education improve body composition, visceral adipose tissue, and cardiorespiratory fitness in children with obesity compared with usual school activity?

Summary

This randomized school-based trial studied 40 children with obesity aged 10-13 years. The intervention group added three weekly running HIIT sessions to regular school activity for 12 weeks, using 15-second runs at 100% maximal aerobic speed alternated with 15-second active recovery. All participants completed the program, no injuries were reported, and the HIIT group improved body mass, BMI, body fat, visceral adipose tissue, and VO2max more than controls. Diet was not strictly controlled, the sample was small, and the study was limited to older primary-school children with obesity.

Methodology

  • Forty children with obesity aged 10-13 years from an elementary school, 20 boys and 20 girls.
  • 40 participants.
  • Outdoor track running.
  • Work intervals: 3 sets of 8 x 15-second runs at 100% MAS.
  • Recovery: 15-second active recovery at 50% MAS; 3 minutes rest between sets.
  • Intensity: 100% MAS, about 80-90% HRmax.
  • 18-minute formal interval block plus warm-up and about 5-minute cool-down.
  • 3 sessions per week.
  • 12 weeks.
  • Parallel randomized controlled trial with intervention and control groups.
  • Body composition, Visceral adipose tissue, VO2max, and Heart rate were tracked.

Outcomes

Body composition

HIIT significantly reduced body mass, BMI, body fat percentage, and fat mass compared with control.

BM -3.4 +/- 1.4 kg, BMI -1.7 +/- 0.5, %BF -3.3 +/- 1.4, FM -3.2 +/- 1.4 kg; all p = 0.001 with large eta2 values.

Improved

Visceral adipose tissue

VAT decreased significantly in the HIIT group but not control.

IG -22.4 +/- 9.8 cm2, p = 0.001, eta2 = 0.61; CG +4.9 +/- 12.7 cm2, p = 0.061.

Improved

VO2max

VO2max increased in both groups, with a greater increase in HIIT.

IG +4.5 +/- 1.6 mL/kg/min, p = 0.001; CG +1.7 +/- 1.1, p = 0.001; between-group increase p < 0.05.

Improved

Safety/adherence

All participants completed the study and no injuries were reported.

40/40 included in final analysis.

Improved

Insights

  • Short 15-second intervals can be embedded into school PE when distances are individualized and visibly marked.
  • A 12-week duration may be important for body-composition effects.
  • Schools need trained staff and screening for contraindications.

Limitations

  • Small sample.
  • Diet not strictly controlled.
  • Short intervention with no long-term follow-up.
  • Younger children under 10 may not be suitable.
  • BIA-estimated VAT rather than imaging.

Safety

  • No injuries were reported.
  • Children with cardiac abnormalities, hypertension, diabetes, orthopedic, or neuromuscular disorders were excluded.
  • Staff supervised all sessions and HR was monitored.