PMID 38357496

Research
All papers

Effects of low-volume functional and running high-intensity interval training on physical fitness in young adults with overweight/obesity

Cao M, Yang B, Tang Y, Wang C, Yin L

Question

How do low-volume functional HIIT and running HIIT compare with control for body composition, muscular fitness, and cardiorespiratory fitness in young adults with overweight or obesity?

Summary

In young adults with overweight or obesity, 12 weeks of low-volume HIIT improved body composition and fitness compared with control. Functional bodyweight HIIT and treadmill running HIIT both improved cardiorespiratory fitness, while functional HIIT better preserved or increased lean mass and improved muscular fitness. Attendance was high in both HIIT arms.

Methodology

  • Young adults with overweight or obesity randomized to functional HIIT, running HIIT, or control.
  • 38 participants.
  • Bodyweight functional exercises.
  • Work intervals: 30 s all-out exercise.
  • Recovery: 30 s rest after each exercise; 1 min rest between sets.
  • Intensity: All-out bouts with heart-rate monitoring.
  • About 25 min.
  • 3 sessions/week.
  • 12 weeks.
  • Three-arm randomized controlled trial comparing functional HIIT, running HIIT, and non-training control.
  • Body composition, Muscular fitness, Cardiorespiratory fitness, and Attendance were tracked.

Outcomes

Body composition

Both HIIT modalities reduced weight, body fat percentage, and visceral fat area; functional HIIT increased lean mass while running HIIT decreased lean mass.

Functional vs running lean-mass change about +1.623 vs -1.034 kg, p<0.001.

Improved

Muscular fitness

Both HIIT arms improved muscular fitness, with functional HIIT showing larger push-up and back-strength gains than running HIIT.

Push-up change HIIT-F vs HIIT-R p<0.001; back-strength change p<0.01.

Improved

Cardiorespiratory fitness

Both functional and running HIIT improved estimated VO2max and shuttle-run performance, with no meaningful VO2max difference between modalities.

VO2max changes about +2.885 vs +2.192 mL/kg/min for HIIT-F vs HIIT-R; p=0.792.

Improved

Attendance

Attendance was high in both HIIT arms.

HIIT-F 96.4%; HIIT-R 93.3%.

Improved

Insights

  • A simple 4 x 4 structure of 30 s all-out bodyweight work can be translated into app programming.
  • Functional HIIT may be a better default than running HIIT when preserving lean mass and improving muscular endurance are goals.
  • High attendance in supervised settings does not guarantee the same adherence in unsupervised app use.

Limitations

  • Small sample.
  • Young adults only.
  • Cardiorespiratory and muscular outcomes relied on field tests.
  • No accelerometer or diary for daily physical activity.
  • Supervised setting limits unsupervised translation.

Safety

  • Sessions were supervised and heart rate was monitored continuously.
  • No major adverse event signal was highlighted in the extracted NXML.