High-Intensity Interval Circuit Training Versus Moderate-Intensity Continuous Training on Cardiorespiratory Fitness in Middle-Aged and Older Women: A Randomized Controlled Trial

• Main Authors: Ismael Ballesta-García, Ignacio Martínez-González-Moro, Domingo J Ramos-Campo, María Carrasco-Poyatos
• Format: Article
• Language: English
• Published: MDPI AG 2020-03-01
• Series: International Journal of Environmental Research and Public Health
• Subjects: high-intensity interval circuit training; peak oxygen consumption; middle-aged; older; women
• Online Access: https://www.mdpi.com/1660-4601/17/5/1805

High-intensity interval training (HIIT) has similar or better effects than moderate-intensity continuous training (MICT) in increasing peak oxygen consumption (VO_2max), however, it has not been studied when HIIT is applied in a circuit (HIICT). The aim of this study was to compare the effects of a HIICT versus MICT on VO_2max estimated (VO_2max-ES), heart rate (HR) and blood pressure (BP) of middle-aged and older women. A quasi-experimental randomized controlled trial was used. Fifty-four women (67.8 &#177; 6.2 years) were randomized to either HIICT (<i>n</i> = 18), MICT (<i>n</i> = 18) or non-exercise control group (CG; <i>n</i> = 18) for 18 weeks. Participants in HIICT and MICT trained two days/week (one hour/session). Forty-one participants were assessed (HIICT; <i>n</i> = 17, MICT; <i>n</i> = 12, CG; <i>n</i> = 12). Five adverse events were reported. Cardiorespiratory fitness, HR and BP were measured. The tests were performed before and after the exercise intervention programs. VO_2max-ES showed significant training x group interaction, in which HIICT and MICT were statistically superior to CG. Moreover, HIICT and MICT were statistically better than CG in the diastolic blood pressure after exercise (DBP_ex) interaction. For the systolic blood pressure after exercise (SBP_ex), HIICT was statistically better than CG. In conclusion, both HIICT and MICT generated adaptations in VO_2max-ES and DBP_ex. Furthermore, only HIICT generated positive effects on the SBP_ex. Therefore, both training methods can be considered for use in exercise programs involving middle-aged and older women.