PMID 30622842

Research
All papers

The Impact of Different High-Intensity Interval Training Protocols on Body Composition and Physical Fitness in Healthy Young Adult Females

Brown EC, Hew-Butler T, Marks CRC, Butcher SJ, Choi MD

Question

Do multimodal and rowing HIIT differ in their effects on body composition, cardiovascular fitness, and muscular fitness in healthy young adult women?

Summary

In a small randomized 12-week trial of healthy nonobese young women, both multimodal HIIT and rowing HIIT improved VO2max, lean mass, bone mineral content, and several strength/power outcomes. Multimodal HIIT improved deadlift 1RM more than rowing HIIT, but most outcomes did not differ between groups.

Methodology

  • Healthy nonobese recreationally active young adult women.
  • 16 participants.
  • Barbell, dumbbell/bodyweight, and sprint-like movements.
  • Work intervals: 60 s.
  • Recovery: 3 min rest.
  • Intensity: As much effort as possible; HR >=90% estimated HRmax.
  • About 60 min session window.
  • 3 sessions/week.
  • 12 weeks.
  • Parallel-group randomized trial
  • Body composition, VO2max, and Muscular fitness were tracked.

Outcomes

VO2max

VO2max improved for the whole sample with no significant group interaction.

F(1,12)=8.52, p=0.01, partial eta squared=0.415.

Improved

Lean mass/BMC

Lean mass and bone mineral content increased in the whole sample with no significant group interaction.

Lean mass p<0.001; BMC p<0.001.

Improved

Deadlift strength

Deadlift 1RM increased more in multimodal HIIT than rowing HIIT.

Time by group F(1,12)=4.85, p=0.048.

Improved

Adiposity

Total body-fat percentage decreased, but fat mass, waist, waist-to-height ratio, and VAT did not significantly change.

Total body fat percentage p=0.04; no significant interactions.

Mixed

Insights

  • Supervised multimodal HIIT can improve strength and aerobic markers but loaded movements require skill preparation.
  • Rowing HIIT plus identical warm-up also improved several muscular fitness outcomes, so strength changes should not be attributed only to resistance circuits.

Limitations

  • Small sample
  • No non-exercise control group
  • Healthy nonobese young women only
  • Some missing outcome data
  • Predicted HRmax used for session intensity
  • No broad-jump familiarization

Safety

  • No adverse events were reported during testing.
  • Two muscle strains occurred outside exercise sessions during the intervention period, one in each group, causing one missed session each.