Cold Water Swimming Beneficially Modulates Insulin Sensitivity in Middle-Aged Individuals

Abstract

We determined whether cold water swimming for six consecutive months results in adaptive changes in body composition and insulin sensitivity. Thirty healthy subjects aged 50.2 ± 9.4 years were exposed to cold water at least twice a week. Body composition was determined and serum glucose and insulin served to calculate beta-cell function, insulin sensitivity, and resistance using HOMA2. Compared with control subjects, swimmers were overweight, and had greater percent body fat and beta cell function. Women had lower values of BMI, fat free mass, muscle mass, visceral adipose tissue level, and greater percent body fat than men. Increased insulin sensitivity and decreased insulin secretion and resistance from beginning to middle of swim season was observed in females and in lean subjects. Findings suggest that men and women differ in regard to body composition and response to repeated cold exposure. Cold water swimming may beneficially modulate insulin sensitivity in cold acclimated lean swimmers.

Sex Differences in Swimming Disciplines—Can Women Outperform Men in Swimming?

“…Two main variables may explain why women can outperform men in open-water swimming: (i) the long distance of~30 km, (ii) and water colder than~20 • C. Potential explanations for the finding that women can achieve a better performance than men can be attributed to differences in anthropometric characteristics such as body composition [65], body weight [66], body fat [67][68][69][70], lean body mass [71,72], body height [73,74], muscle thickness [75] and muscle size [72]. Other possible explanations were differences in swimming biomechanics such as kinematic parameters [76], arm coordination and arm-leg coordination [76][77][78], energetic cost, differences in swimming economy and swimming efficiency [79][80][81], gliding [82], body roll [83], shoulder flexibility [84], trunk flexibility [85], knee flexibility [86,87], propelling efficiency [88].…”

Concentrations of Ca, Mg, P, Prostaglandin E2 in Bones and Parathyroid Hormone; 1,25-dihydroxyvitamin D3; 17-β-estradiol; Testosterone and Somatotropin in Plasma of Aging Rats Subjected to Physical Training in Cold Water

“…Exposure to low temperatures can be considered a stressor, which when applied for a specific time can lead to adaptive reactions [ 6 , 23 , 24 ]. Therefore, in our study we hypothesized that cold, when applied to the entire body, may be a factor that positively modifies the aging process of bones by improving the mechanisms related to the body’s mineral balance.…”

Cold Water Swimming—Benefits and Risks: A Narrative Review

“…Cardiovascular system Lowering blood pressure [23,47,53,54] Endocrine system Decrease in triglycerides [24,31,55] Increase in insulin sensitivity [3,11,31,56] Decrease in norepinephrine […”

“…Several studies have suggested that cold water swimming has a wide variety of health benefits [3], including changes in hematological [4] and endocrine function [5,6], fewer upper respiratory tract infections [7], amelioration of mood disorders [8] and general well-being [9]. Although chronic exposure to colder water temperatures has been shown to be beneficial to one's health, several studies have outlined the potential risks [10][11][12][13].…”