The chronic leukocyte and inflammatory cytokine responses of older adults to resistance training in normobaric hypoxia; a randomized controlled trial

Giselle Larissa Allsopp; Alex Bernard Addinsall; Garth Stephenson; Faiza Basheer; Paul Adrian Della Gatta; Samantha May Hoffmann; Aaron Paul Russell; Craig Robert Wright

doi:10.1186/s13102-024-00890-w

The chronic leukocyte and inflammatory cytokine responses of older adults to resistance training in normobaric hypoxia; a randomized controlled trial

BMC Sports Sci Med Rehabil. 2024 May 2;16(1):102. doi: 10.1186/s13102-024-00890-w.

Authors

Giselle Larissa Allsopp¹, Alex Bernard Addinsall^{2

3}, Garth Stephenson⁴, Faiza Basheer^{4

5}, Paul Adrian Della Gatta², Samantha May Hoffmann⁶, Aaron Paul Russell², Craig Robert Wright²

Affiliations

¹ Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Victoria, Australia. g.allsopp@deakin.edu.au.
² Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Victoria, Australia.
³ Department of Physiology and Pharmacology, Karolinska Insitutet, Stockholm, 171 77, Sweden.
⁴ School of Medicine, Deakin University, Geelong, Victoria, Australia.
⁵ Institute for Mental and Physical Health and Clinical Translation (IMPACT), Deakin University, Geelong, Victoria, Australia.
⁶ Centre for Sport Research (CSR), School of Exercise and Nutrition Sciences, Deakin University, Victoria, Australia.

Abstract

Trial design: Older adults experience chronic dysregulation of leukocytes and inflammatory cytokines, both at rest and in response to resistance training. Systemic hypoxia modulates leukocytes and cytokines, therefore this study characterized the effects of normobaric hypoxia on the leukocyte and cytokine responses of older adults to resistance training.

Methods: 20 adults aged 60-70 years performed eight weeks of moderate-intensity resistance training in either normoxia or normobaric hypoxia (14.4% O₂), consisting of two lower body and two upper body exercises. Venous blood was drawn before and after the training intervention and flow cytometry was used to quantify resting neutrophils, lymphocytes, monocytes, eosinophils and basophils, in addition to the subsets of lymphocytes (T, B and natural killer (NK) cells). Inflammatory cytokines were also quantified; interleukin 1 beta (IL-1β), IL-4, IL-6, IL-8, IL-10 and tumor necrosis factor alpha (TNF-α). Acute changes in leukocytes and cytokines were also measured in the 24 h following the last training session.

Results: After the intervention there was a greater concentration of resting white blood cells (p = 0.03; 20.3% higher) T cells (p = 0.008; 25.4% higher), B cells (p = 0.004; 32.6% higher), NK cells (p = 0.012; 43.9% higher) and eosinophils (p = 0.025; 30.8% higher) in hypoxia compared to normoxia, though the cytokines were unchanged. No acute effect of hypoxia was detected in the 24 h following the last training session for any leukocyte population or inflammatory cytokine (p < 0.05).

Conclusions: Hypoxic training caused higher concentrations of resting lymphocytes and eosinophils, when compared to normoxic training. Hypoxia may have an additional beneficial effect on the immunological status of older adults.

Trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR).

Trial number: ACTRN12623001046695. Registered 27/9/2023. Retrospectively registered. All protocols adhere to the COSORT guidelines.

Keywords: Aging; Inflammation; Simulated altitude; Strength training; White blood cells.