PMID 31269007

Research
All papers

High-Intensity Interval Training Is Feasible in Women at High Risk for Breast Cancer

Coletta AM, Brewster AM, Chen M, Li Y, Bevers TB, Basen-Engquist K, Gilchrist SC

Question

Is supervised treadmill HIIT feasible and safe for overweight or obese postmenopausal women at high risk for breast cancer, and how do preliminary fitness effects compare with MICT and usual care?

Summary

In overweight or obese postmenopausal women at high risk for breast cancer, a supervised 12-week treadmill HIIT program was feasible, with retention and adherence similar to moderate continuous training. HIIT improved cardiorespiratory fitness more clearly than usual care, but the small trial was not powered to determine cancer prevention or broad body-composition effects.

Methodology

  • Postmenopausal overweight/obese women at high risk for breast cancer.
  • 44 participants.
  • Treadmill.
  • Work intervals: 4 min at 90-100% HRpeak.
  • Recovery: 3 min active recovery at 50-70% HRpeak.
  • Intensity: HRpeak-based; recalibrated after 6-week CPET.
  • 33 min.
  • 3 sessions/week.
  • 12 weeks.
  • Three-arm randomized feasibility trial.
  • Feasibility, VO2peak, Treadmill exercise time, and Body weight and BMI were tracked.

Outcomes

Feasibility

HIIT had high adherence among completers and similar adverse event counts to MICT.

Retention 33/42 among baseline-intending participants; adherence 90% HIIT and 89% MICT.

Improved

Cardiorespiratory fitness

HIIT improved VO2peak, peak METs, and treadmill exercise time; usual care improved less than HIIT.

VO2peak versus usual care +0.15 L/min, p = .005; relative +2.3 mL/kg/min, p = .004.

Improved

Exercise time

HIIT improved treadmill time more than both comparators.

+101 s versus MICT and +125 s versus usual care, p < .001.

Improved

Body weight and BMI

No significant group effect for weight or BMI.

p > .05.

No clear change

Insights

  • 4 x 4 min treadmill HIIT can be feasible in a screened clinical prevention population when supervised.
  • Safety screening matters; symptoms occurred even in a supervised trial.
  • Fitness outcomes are stronger than weight outcomes.

Limitations

  • Small feasibility trial.
  • Underpowered for secondary outcomes.
  • Supervised clinic setting limits scalability.
  • Special high-risk postmenopausal population.
  • No cancer incidence endpoint.

Safety

  • No serious adverse events were reported.
  • Six HIIT adverse events and four MICT adverse events were reported.
  • Two exercise sessions were discontinued because of shortness of breath or dizziness.
  • Muscle soreness and joint pain were listed as possibly related.