EXERCISE TRAINING AND CARDIOVASCULAR HEALTH: A PRELIMINARY REPORT OF THE MICROFIT STUDY. FOCUS ON EXERCISE PERFORMANCE

Purpose: Arterial hypertension is a major cardiovascular risk factor and is influenced by exercise training. The gut microbiota has been shown to regulate pathways associated with exercise training. However, literature lacks information on the relationship between exercise training and gut microbiota. We aim to test the exercise performance modifications after the assumption of probiotics in comparison with physical training. Methods: This randomized partially double-blinded controlled trial (NCT05967715) enrolled 75 controlled and stable hypertensive patients (aged from 40 to 65 years, in primary cardiovascular prevention, without diabetes and inflammatory disorders), randomized into 3-month intervention arms: exercise training; probiotics; placebo. The exercise group performs high intensity interval training 1 hour thrice a week; probiotic group receives multi-strain probiotics for three months. Probiotic and placebo groups are double blinded. Clinical, familial and drug history are obtained. Before and after the intervention, fitness assessment is performed measuring muscle force of the upper limb (HandGrip Test) and of the lower limb (30-second Chair-Stand Test - 30s-CST), functional capacity (6-minute walking test - 6MWT) and aerobic capacity (Step test). In 30 patients, another measure of exercise ability is obtained by cardiopulmonary exercise testing (CPET), also referred to as VO2 (oxygen consumption). Results: This preliminary report is based on 52 patients who first completed the 3-month intervention. Analysis was blinded to the intervention group. We observed substantial homogeneity of the baseline characteristics among the 3 groups, except for slight variation in the 30s-CST and in time of exercise and watt percent on the CPET. After the intervention, the fitness assessment showed significant improvement in the 30s-CST and in the Handgrip Test dx in the 3rd group; moreover, it showed a significant reduction in the Mean Heart Rate both at the Step Test and the 6MWT in the 1st group, but a significant increase in the 3rd. Regarding the CPET, data before and after the intervention showed an improvement in both percent increment of VO2 peak/kg and variation of VO2 peak/kg in the 2nd and 3rd group, but the small sample size did not allow to show statistical differences. Conclusions: Preliminary blinded results demonstrate a separation of the three arms concerning strength performance after the intervention, while a non-significant trend was observed in aerobic performance.