PMID 26406234

Research
All papers

Effects of High Intensity Interval Training and Strength Training on Metabolic, Cardiovascular and Hormonal Outcomes in Women with Polycystic Ovary Syndrome: A Pilot Study

Almenning I, Rieber-Mohn A, Lundgren KM, Shetelig Løvvik T, Garnæs KK, Moholdt T

Question

Do HIIT and strength training improve metabolic, cardiovascular, and hormonal outcomes in women with PCOS compared with usual-care control?

Summary

In women with PCOS, 10 weeks of supervised HIIT improved insulin resistance and HDL cholesterol compared with control, while strength training improved some body-composition and hormonal outcomes. The study was small and exploratory.

Methodology

  • Women diagnosed with PCOS by Rotterdam criteria
  • 31 participants.
  • Self-selected treadmill, outdoor walking/running, or cycling.
  • Work intervals: Two weekly sessions of 4 x 4 minutes at 90-95% HRmax; one weekly session of 10 x 1 minute maximal/all-out efforts.
  • Recovery: 3 minutes at about 70% HRmax for 4 x 4 sessions; 1 minute rest or very low activity for 10 x 1 sessions.
  • Intensity: 90-95% HRmax or maximal/all-out depending on session.
  • Not fully specified; structured interval sessions performed 3 times weekly.
  • 3 sessions per week.
  • 10 weeks.
  • Pilot three-arm randomized controlled trial
  • Insulin resistance, Lipids, Vascular function, and Body composition were tracked.

Outcomes

HOMA-IR

Insulin resistance improved after HIIT compared with control.

HIT change -0.83, 95% CI -1.45 to -0.20; between-group p=0.014; HIT vs control p=0.013.

Improved

HDL

HDL cholesterol increased after HIIT.

HIT change +0.2 mmol/L, 95% CI 0.02 to 0.5; between-group p=0.04.

Improved

Body fat

Fat percentage decreased after both HIIT and strength training, while body weight and waist circumference did not clearly change.

Fat percentage decreased by -0.9 after HIT and -1.6 after strength training; weight and waist were unchanged.

Improved

FMD

Flow-mediated dilation increased after HIIT, but the between-group test was not conventionally significant.

HIT change +2.0 percentage points, 95% CI 0.1 to 4.0; between-group p=0.08.

Mixed

Insights

  • A mixed HIIT week combining 4 x 4 minute intervals and 1-minute maximal intervals was feasible for many women with PCOS.
  • Heart-rate monitoring and weekly diary review supported intensity fidelity.
  • Clinical PCOS programming should account for dropout and medication/diet confounding.

Limitations

  • Pilot sample with many outcomes and no multiple-testing adjustment.
  • Participants using oral contraceptives were included if stable.
  • Diet was not controlled.
  • HOMA-IR was used rather than clamp methods.
  • The HIIT arm combined two different interval protocols.

Safety

  • The authors reported no adverse events. Six of 31 women dropped out during the study.