Although High-intensity interval training (HIIT) exercise has emerged in recent years as a powerful time-efficient alternative to moderate-intensity continuous cardiovascular exercise training (MICT) to enhance neuroplasticity, motor, and cognitive functions, its feasibility remains to be determined early after stroke. Our study aims to investigate the feasibility of the HIIT program and its effects on functional abilities, cognitive function, and quality of life in early post-stroke.

Study design, setting, and ethical considerations:

This study will be a prospective pre-post study that will be conducted at the university hospital of Parakou in Benin. The study protocol will be submitted to the ethics committee of Hasselt University in Belgium and the local biomedical ethics committee of the University of Parakou, Republic of Benin.

Interventions:

The experimental protocol will be preceded by 30 minutes of conventional physiotherapy, including neuromuscular interventions (balance training, postural awareness), musculoskeletal interventions (passive range of motion, stretching, strengthening), and lower-intensity overground walking. The conventional physiotherapy will be followed by 15 min of the rest period, then the experimental protocol consisting of a HIIT program on a recumbent cycle SOLE R92 (HIIT-REC) will be performed three times per week for six successive weeks.21 Training will be performed on non-consecutive days, thereby permitting recovery between sessions. The HIIT procedure will start at 4-min at 30% of the peak workload interspersed with 1-min at 70% of the peak workload at 50 rpm for weeks 1-2 and increased by approximately 5 minutes every two weeks as tolerated to reach 30 minutes from week 5 (4 to 6 repetitions). The training intensity will progress similarly by 5% peak workload two weeks as tolerated to reach 4-min at 40% peak workload interspersed with 1-min 80% peak workload from week-5.22 All sessions will be supervised and performed individually with verbal encouragement.

Inclusion Criteria:

1. first episode from an ischemic or hemorrhagic stroke confirmed by CT scan;
2. muscular weakness of the leg on the hemiplegic side defined as NIHSS-Item 6 score between 1 and 3;
3. Ashworth score of 0 or 1, indicating no spasticity or slight spasticity over the affected lower limb, respectively
4. able to walk at least 5 meters independently with or without assistive devices and understand spoken instructions;
5. living in Parakou or the surrounding area and wishing to undergo the program at the hospital.

Exclusion Criteria:

Participants:

1. unable to perform a graded exercise test, i.e., unable to maintain the designated pedaling rate;
2. cardiovascular diseases (uncontrolled arrhythmias, decompensated heart failure or recent myocardial injury, arteriopathy);
3. primary orthopedic conditions (fractures, active rheumatoid arthritis);
4. other neurological diseases such as (Parkinson's disease and Alzheimer's disease).

Data will be available to researchers upon request to the first author (ERA)