Investigation of the Effectiveness and Safety of the Rehabilitation Program for Patients with Long Covid Using Aquatic Training
Authors: Lobanov Andrey A. , Grishechkina Irina A. , Fesyun Anatoliy D. , Rachin Andrey P. , Yakovlev Maxim Yu. , Andronov Sergey V. , Barashkov Gleb N. , Lebedeva Olga D. , Popov Andrey I. , Styazhkina Elena M. , Ansokova Mar’yana A. , Vasil’eva Valeriya A. 
Published: November 2022

Aim. To evaluate the effectiveness and safety of aquatic training in diluted sodium chloride bromine brine in restoring the functional state of the organism of patients with portcovid syndrome in comparison with aquatic training in fresh water.
Material and methods. Specialists of the National Medical Research Centre of Rehabilitation and Balneology of the Ministry of Health of Russia conducted an open, prospective, randomized study to evaluate the effect of a course of aquatic training in a bromine sodium chloride brine pool. The study included 28 subjects, who were divided into 2 equal groups. Patients in both groups were comparable for gender (χ2 =0.45; p=0.31) and age (U=99.5; p=0.7) and all had post COVID-19 (U 09.9) as their primary diagnosis. The intervention group received a course of aquatic training (7 treatments) in a pool with bromine sodium chloride brine (well No. 69, 32 Novy Arbat Street, Moscow) with mineralization of 120 g/dm3 and its preliminary dilution to 40 g/m3. Control group – a course of aquatic-exercises (7 treatments) in a fresh water pool. Patients, after signing informed consent, underwent load tests: 6-minute walking test, laser Doppler
flowmetry (“LASMA ST”, Russia), cardiointervalography (“Health Reserves-R”, Russia).
Results and discussion. These data confirm the “null” hypothesis of a more favorable effect of the chemical composition of the diluted brine that acts during aquatic training on the patient’s body compared to fresh water, especially in the presence of microcirculation disorders after suffering COVID-19.
The group of patients who received aquatic training in the pool with bromine sodium chloride brine revealed a significant decrease in excessive sympathetic nervous system activity (T-11.0; p=0.02) at the end of the study. According to LAZMA-ST data, there was a twofold increase in the oxidative metabolism of the cell (IOM T-16.0; p <0.01), an increase in exercise tolerance (6-minute walk test T-10.0; p =0.01). IOM increased statistically significantly threefold (U-32.0; p<0.001), mean microcirculation doubled (U 120.0; p<0.05) and BMI decreased by 20.0% (U-58.0; p<0.05) in the intervention group compared with the control group. There were no significant differences between patient groups on safety parameters (χ2= 1.36; p>0.05). These data confirm the “null” hypothesis of a more favorable effect of the chemical composition of the diluted brine that acts during aquatic training on the patient’s body compared to fresh water, especially in the presence of microcirculation disorders after suffering COVID-19.
Conclusion. Aquatic training in sodium chloride bromide brine effectively reduces the sympathetic nervous system activity, increases oxidative metabolism and improves microcirculation compared to aquatic training in fresh water.