AIM   To explore the efficacy of moderate-intensity continuous training (MICT) and moderate-intensity interval training (MIIT) in patients with chronic heart failure (CHF).

  METHODS  The research was a prospective randomized controlled study. Ninety-four patients with stable CHF admitted to the Department of Cardiovascular Medicine, Zhujiang Hospital Affiliated to Southern Medical University from August 2021 to January 2022 were randomly divided into control group and research group, with 47 cases in each group. The patients in both groups received routine health education. The MICT exercise mode was applied in control group and MIIT exercise mode in study group, with ≥3 times of exercise, each time ≥30 min/week and for a total of 16 weeks. According to the exercise data recorded by the patients’ exercise bracelet, the exercise compliance of the two groups of patients was calculated and the exercise fatigue reported by the CHF patients was counted after weekly exercise. Exercise endurance was evaluated by 6MWD and incremental power exercise endurance test, handgrip strength was measured by handgrip force meter, left ventricular ejection fraction (LVEF) was measured by cardiac color ultrasonography and quality of life was evaluated by the Chinese version of Minnesota Heart Failure Quality of Life Scale (MLHFQ).

  RESULTS  There was no statistical difference in general data between the two groups. The rate of reaching the standard of exercise time and exercise intensity of CHF patients in MIIT group was significantly higher than that in mict group, and the times of stopping exercise in MIIT group was significantly lower than that in mict group (all P<0.01). At week 0, the proportion of exercise fatigue in the MIIT group was higher than that in the mict group (P<0.05). With the passage of time, the proportion of exercise fatigue in the two groups gradually approached and reversed. When the exercise fatigue week was ≥ 9 weeks, the proportion of exercise fatigue in the MIIT group was lower than that in the mict group (P<0.05); The data of 6MWD, exhaustion time and maximum power load after exercise in the two groups were significantly higher than that at the time of enrollment (all P<0.01), and the increase was more significant in the MIIT group (all P<0.01); The scores and total scores (P<0.05, P<0.01) of the two groups (mict group and MIIT group) in the emotional field (all P<0.05), physical field (P<0.05, P<0.01) and other fields (P<0.05, P<0.01) of the mlhfq scale after exercise were lower than those of the group when the group was enrolled, and the difference was statistically significant; The scores of 4 items after exercise in mitt group were also lower than those in mict group (P<0.05, P<0.01).

  CONCLUSION  Compared with MICT exercise mode, CHF patients have better compliance with MIIT exercise mode and lower fatigue. CHF patients have more significant improvement in exercise tolerance and quality of life after MIIT exercise mode.