Autonomic regulation of the nervous system and metabolic processes in swimmers competing for a record in ice water

Aim. The paper aims to show the dynamics of autonomic regulation of the nervous system, glucose, and fat mass in long-distance swimmers with weights of 18 kg competing for a record in ice water (Russian Book of Records). Material and methods. Changes in the Kerdo index, body mass index, body fat mass, and glucose were identified. Results. The participants in this extreme swimming race were found to be overweight according to BMI. No significant differences were found in terms of BMI and BFM (percentage and absolute values) before and after the swimming race. Before measurements, athletes demonstrated anabolic-type metabolism, followed by the prevalence of sympathetic regulation or a balance between sympathetic and parasympathetic activities after the swimming race. After the second measurement, a significant increase in glucose levels (p