Effects of reduced-exertion high-intensity training versus short moderate-intensity continuous training on biomarkers of mortality risk in sedentary women: A randomized clinical trial

Abstract

Introduction

This study aimed to compare the effects of reduced-exertion high-intensity training (REHIT) versus short moderate-intensity continuous training (SMICT) on functional capacity, resting heart rate (RHR), and activity enjoyment in sedentary women.

Methods

Thirty sedentary young women were randomly allocated to a: i) REHIT group (n = 15) or ii) SMICT group (n = 15) (2 sessions/week, 6 weeks) using a computer-generated random allocation sequence. Both groups performed an intervention on a cycle ergometer that included a warm-up (3 min at 50% of HRmax), the main part of the session, and a cool-down (3 min at 50% of HRmax). The main part in REHIT consists of 20–40 s divided on two maximum cycling sprints of all-out exercise at 100% of HRmax with an active rest of 3 min between them; whilst SMICT consisted of 6–12 min of moderate intensity exercise at 60–70% of HRmax. Functional capacity (6-min walking test) and RHR were measured before and after the intervention. Physical activity enjoyment (Physical Activity Enjoyment Scale) was assessed after the intervention.

Results

The effects of the REHIT on functional capacity showed a significant interaction between time measurement and intervention group (p < 0.001) that not occurred in RHR (p > 0.05). Intragroup post-hoc analysis revealed that both groups improve their values in functional capacity and RHR (p < 0.05). Between-groups comparison showed that REHIT group increased significantly functional capacity more than SMICT (p = 0.002). In addition, physical activity enjoyment scores were high in both groups without differences.

Conclusion

REHIT and SMICT are appropriate for improving functional capacity and RHR, as well as being perceived as enjoyable in sedentary young women. REHIT offers higher improvements in functional capacity.

Clinical trial registration number

NCT05875051.