Vol. 2, Issue 1, Part A (2025)

Background: Cardiac rehabilitation is a critical component in the recovery and long-term management of cardiovascular disease. Traditionally, moderate-intensity continuous training (MICT) has been the cornerstone of exercise-based rehabilitation. However, high-intensity interval training (HIIT) has recently emerged as a time-efficient and potentially more effective alternative.

Objective: To compare the effects of HIIT and MICT on aerobic capacity, autonomic function, functional endurance, resting cardiovascular parameters, and quality of life in phase II cardiac rehabilitation patients.

Methods: A randomized controlled trial involving 36 stable cardiac patients (aged 40-70) was conducted over 8 weeks at the Nairobi Heart and Wellness Centre. Participants were randomly assigned to either HIIT or MICT, each performed thrice weekly under supervision. Primary outcomes included VO₂ max, heart rate variability (HRV), 6-minute walk test (6MWT), resting heart rate, and SF-36 quality of life scores. Data were analyzed using paired and independent t-tests.

Results: Both groups showed significant improvements in all outcome measures. However, the HIIT group demonstrated superior gains in VO₂ max (+5.7 vs +2.9 mL/kg/min), HRV (+10.3 vs +4.3 ms), 6MWT distance (+66 vs +38 m), resting HR (−8 vs −4 bpm), and quality of life scores (+11.7 vs +6.1 points). No serious adverse events were reported.
Conclusion: HIIT is a safe, effective, and time-efficient modality that yields greater improvements than MICT in key clinical and functional parameters. Its integration into cardiac rehabilitation protocols should be considered, particularly in resource-constrained settings.
Background: Cardiac rehabilitation is a critical component in the recovery and long-term management of cardiovascular disease. Traditionally, moderate-intensity continuous training (MICT) has been the cornerstone of exercise-based rehabilitation. However, high-intensity interval training (HIIT) has recently emerged as a time-efficient and potentially more effective alternative.
Objective: To compare the effects of HIIT and MICT on aerobic capacity, autonomic function, functional endurance, resting cardiovascular parameters, and quality of life in phase II cardiac rehabilitation patients.
Methods: A randomized controlled trial involving 36 stable cardiac patients (aged 40-70) was conducted over 8 weeks at the Nairobi Heart and Wellness Centre. Participants were randomly assigned to either HIIT or MICT, each performed thrice weekly under supervision. Primary outcomes included VO₂ max, heart rate variability (HRV), 6-minute walk test (6MWT), resting heart rate, and SF-36 quality of life scores. Data were analyzed using paired and independent t-tests.
Results: Both groups showed significant improvements in all outcome measures. However, the HIIT group demonstrated superior gains in VO₂ max (+5.7 vs +2.9 mL/kg/min), HRV (+10.3 vs +4.3 ms), 6MWT distance (+66 vs +38 m), resting HR (−8 vs −4 bpm), and quality of life scores (+11.7 vs +6.1 points). No serious adverse events were reported.
Conclusion: HIIT is a safe, effective, and time-efficient modality that yields greater improvements than MICT in key clinical and functional parameters. Its integration into cardiac rehabilitation protocols should be considered, particularly in resource-constrained settings.