Abstract
ABSTRACT Aging is associated with impairments in thermoregulatory function, which may augment the neuroendocrine and immune response in older relative to young adults during physical activity in the heat. This study was therefore aimed at examining changes in circulating endocrine hormones as cortisol (COR), prolactin (PRL), human growth hormone (hGH) and interleukin-6 (IL-6) in young and older men prior to and following an incremental, exercise-heat stress protocol (40°C and ~15% relative humidity). Accordingly, ten habitually active young (mean±SD; 21 ± 1 years) and ten older (65 ± 3 years) men performed three 30-min bouts of cycling at increasing metabolic heat productions (300, 400 and 500 W, equal to light, moderate and vigorous exercise), each separated by a 15-min recovery. Consistent with our hypothesis, we observed augmented IL-6 in older (3.55 ± 1.62 pg/mL) compared to young men (1.59 ± 0.88 pg/mL) following the protocol (p < 0.001). However, no significant between-group differences were observed for COR and hGH (all p > 0.050). We show that when assessed following incremental exercise in the heat, older men display augmented interleukin-6, but similar levels of stress hormones relative to young men.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.