Effect of the Marine Exercise Retreat Program on Thyroid-Related Hormones in Middle-Aged Euthyroid Women

Int J Environ Res Public Health. 2023 Jan 14;20(2):1542. doi: 10.3390/ijerph20021542.

Abstract

This study aimed to investigate the effects of a marine exercise retreat program on thyroid-related hormone levels. A total of 62 middle-aged euthyroid women participated in a 6-day marine exercise retreat program. Using thyroid-stimulating hormone (TSH) and free thyroxine (fT4) hormone levels, the participants were divided into high and low-hormone-level groups. Despite decreased TSH and fT4 levels after the program, the factors influencing changes in each group were different. TSH levels were influenced by changes in the normalized low frequency (nLF) of heart rate variability and carbon monoxide (CO) from all the participants, and changes in body fat percentage, nLF, and nitrogen dioxide (NO2) exposure level in the high TSH group. fT4 levels were influenced by changes in body mass index (BMI), NO2 exposure, and particulate matter diameter of 10 µm or less (PM10) exposure in all participants. Changes in BMI and CO exposure influenced the low fT4 group. Lastly, changes in the exercise stress test affected the high fT4 group. Thus, the marine exercise retreat program affected euthyroid thyroid-related hormone levels, and influencing factors differ depending on the initial value of the hormone.

Keywords: Free T4; TSH; blue-space; euthyroid; heart rate variability; marine retreat program; thyroid hormones.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Female
  • Humans
  • Middle Aged
  • Nitrogen Dioxide
  • Thyroid Gland
  • Thyroid Hormones
  • Thyrotropin
  • Thyroxine*
  • Triiodothyronine*

Substances

  • Thyroxine
  • Triiodothyronine
  • Nitrogen Dioxide
  • Thyroid Hormones
  • Thyrotropin

Grants and funding

This work was supported by the Wando Marine Healing Blue Zone Creation Project funded by the Presidential Committee for Balanced National Development in South Korea.