Daily physical activity is negatively associated with thyroid hormone levels, inflammation, and immune system markers among men and women in the NHANES dataset

Abstract

The acute effects of exercise on metabolic energy expenditure and inflammation are well studied, but the long-term effects of regular daily physical activity on metabolic and endocrine effects are less clear. Further, prior studies investigating the impact of daily physical activity in large cohorts have generally relied on self-reported activity. Here, we used the U.S. National Health and Nutrition Examination Survey (NHANES) to investigate the relationship between daily physical activity and both thyroid and immune activity. Daily physical activity was assessed through accelerometry or accelerometry-validated survey responses. Thyroid activity was assessed from circulating levels of thyroid stimulating hormone (TSH) and thyroxine (T4). Immune function was assessed from circulating cytokines (C-reactive protein [CRP], immunoglobulin E [IgE], fibrinogen) and blood cell counts. In general linear models including body mass index, age, gender, activity and TSH as factors, active adults had a lower levels of T4 and reduced slope of the TSH:T4 relationship. Similarly, greater physical activity was associated with lower CRP and fibrinogen levels (but not IgE) and lower white blood cell, basophil, monocyte, neutrophil, and eosinophil (but not lymphocyte) counts. Daily physical activity was also associated with lower prevalence of clinically elevated CRP, WBC, and lymphocytes in a dose-response manner. These results underscore the long-term impact of daily physical activity on both systemic metabolic activity (thyroid) and on specific physiological tasks (immune). The regulatory effects of physical activity on other bodily systems are clinically relevant and should be incorporated into public health strategies promoting exercise.

Relationship between Euthyroidism and Muscle Mass and Strength: A Systematic Review

“…Indeed, it is known that thyroid function could be affected by physical exercise despite its physiologic responses are difficult to characterize fully [39,40]. A recent study showed that physically active adults tended to have lower TSH and T4 levels and at low levels of T4 seem to produce less TSH [41]. These results suggest that physical activity may affect metabolic energy expenditure through effects on thyroid hormone signaling [41].…”

Influence of routine exercise on the peripheral immune system to prevent and alleviate pain

“…In healthy human subjects, acute bouts of exercise transiently increase inflammation, while regular exercise may act as an anti-inflammatory treatment ( Walsh et al, 2011 , Campbell and Turner, 2018 , Klasson et al, 2022 , Sellami et al, 2021 , Zhao et al, 2012 , Chastin et al, 2021 , Shimizu et al, 2008 , Simpson et al, 2020 , Ferreira et al, 2018 , Cantó et al, 2018 , Scheffer and Latini, 2020 , Nieman and Pence, 2020 , Nieman and Wentz, 2019 , Suzuki, 2018 , Cerqueira et al, 2019 ). Acute bouts of exercise elicit a cascade of inflammatory events measured by changes in PBMC counts, lymphocyte subpopulations (T cells, B cells, natural killer (NK) cells), granulocyte, neutrophil and NK cell activity, lymphocyte proliferation, and cytokine levels in plasma ( Nieman, 1997 , Gabriel and Kindermann, 1997 , Pedersen, 1991 , Gonçalves et al, 2019 , Moldoveanu et al, 2001 ).…”

“…Since regular exercise has the capacity to modulate immune function to enhance anti-inflammatory activity of immune cells in healthy people and animal models ( Walsh et al, 2011 , Calcaterra et al, 2022 , Klasson et al, 2022 , Campbell and Turner, 2018 , Zhao et al, 2012 , Shimizu et al, 2008 , Sellami et al, 2021 , Chastin et al, 2021 , Oliveira-Fusaro et al, 2020 , Sluka and Gregory, 2015 , Gregory et al, 2018 , Gregory et al, 2015 , Leung et al, 2016 , Leung et al, 2016 , da Silva et al, 2015 , Nijs et al, 2014 , Polli et al, 2019 , Clark et al, 2017 , Liu and Wang, 1987 , Kohut et al, 2001 , Baek et al, 2020 , Cannon and Kluger, 1984 ), it is important to determine if regular exercise modulates the immune system in chronic pain populations. Prior randomized controlled trials using various modes of exercise ranging from aerobic (cardiorespiratory), muscle strengthening, stretching, and aquatic based exercise show varying effects on immune function.…”

COVID-19: Insights into long-term manifestations and lockdown impacts

“… 140 , 141 , 142 , 143 , 144 In contrast, daily PA positively impacts the immune system. 145 , 146 , 147 Several studies reported positive effects, such as higher levels of natural killer cells (NKs), neutrophils, lymphocytes, monocytes, and plasma interleukin-6, as well as an increased function of NKs and a decrease in inflammation. 28 , 148 , 149 , 150 , 151 Thus, several studies additionally focused on investigating whether PA is related to COVID-19 outcomes and severity.…”