Supervised high-intensity interval training reduces the negative effect of chemotherapy on cardiorespiratory fitness in young breast cancer women: a randomised controlled study
Question
Whether supervised HIIT performed concurrently with chemotherapy affects cardiorespiratory fitness and cardiovascular measures in young breast cancer patients during the preoperative period.
Summary
In young women with breast cancer receiving neoadjuvant chemotherapy, a 6-month supervised HIIT program delivered during chemotherapy reduced the chemotherapy-associated decline in cardiorespiratory fitness compared with usual activity guidance. Relative peak VO2 and exercise time still declined, but the decline was smaller in the HIIT group, and no exercise-related adverse events were observed.
Methodology
- Young women aged 18-40 with histopathologically confirmed breast cancer scheduled for neoadjuvant chemotherapy.
- 26 participants.
- Circuit using treadmill, elliptical bike, cycloergometer, rowing machine, and endurance stepper.
- Work intervals: Month 1: 1 min 15 s; month 2: 1 min 30 s; months 3-4: 1 min 45 s; months 5-6: 2 min.
- Recovery: 4 min active walking recovery to lower HR to about 120 bpm.
- Intensity: 75% HRmax in month 1; 80%-90% HRmax in months 2-6.
- About 40 min.
- 2 supervised sessions/week plus one 45-min individual aerobic session/week.
- 6 months.
- Open-label, parallel, randomized controlled study.
- Relative peak VO2, Exercise time, Ventilatory anaerobic threshold, and Resting hemodynamic parameters were tracked.
Outcomes
Relative peak VO2
Peak VO2 declined in both groups after chemotherapy, but the decrease was significantly smaller in the HIIT group than in control.
HIIT 33.630 to 29.540 mL/kg/min; control 29.679 to 22.571 mL/kg/min; ANCOVA p = 0.018, ES = 0.469.
Exercise time
Control group exercise time decreased substantially, while HIIT group exercise time was largely maintained.
HIIT 685.600 to 666.500 s; control 703.357 to 555.500 s; ANCOVA p = 0.008, ES = 0.815.
Ventilatory anaerobic threshold
Only the HIIT group showed a significant within-group decrease, but there was no significant between-group difference.
No significant difference between CTR and HIIT groups.
Resting cardiac output/hemodynamic parameters
HIIT group showed decreased SV and SVi after chemotherapy; control showed increased SVR and SVRi; between-group differences were not significant.
No between-group difference noted for SV/SVi; no statistically significant between-group differences for CPET parameters measured at rest.
Exercise-related adverse events
No adverse events related to exercise intervention were observed in the HIIT group.
Insights
- For medically cleared young breast cancer patients, supervised HIIT during chemotherapy may attenuate loss of cardiorespiratory fitness.
- Clinical HIIT programming should use supervision, heart-rate monitoring, gradual progression, and recovery criteria.
- For consumer HIIT content, this paper should be used as condition-specific background rather than direct workout prescription.
Limitations
- Single-centre study.
- Small sample size.
- No dietary habit data.
- No extended follow-up period.
- Open-label design and clinical special population.
Safety
- No adverse events related to exercise intervention were observed in the HIIT group.
- Eligibility was determined by an oncologist and cardiologist before group allocation.
- Heart rate was monitored during every supervised training session.