title: Physiological responses to psychological stress: importance of adiposity in men aged 50-70 years.
abstract: We tested the hypothesis that overweight/obese men aged 50-70 years will have a greater salivary cortisol, salivary alpha amylase and heart rate (HR) responses to psychological stress compared with age matched lean men. Lean (BMI=20-25 kg/m(2); n=19) and overweight/obese (BMI=27-35 kg/m(2); n=17) men (50-70 years) were subjected to a well-characterised psychological stress (Trier Social Stress Test, TSST) at 1500 h. Concentrations of cortisol and alpha amylase were measured in saliva samples collected every 7-15 min from 1400 to 1700 h. HR was recorded using electrocardiogram. Body weight, BMI, percentage body fat, resting systolic and diastolic blood pressure and mean arterial pressure were significantly higher (P<0.05) in overweight/obese men compared with lean men. Both groups responded to the TSST with a substantial elevation in salivary cortisol (372%), salivary alpha amylase (123%) and HR (22%). These responses did not differ significantly between the groups (time×treatment interaction for salivary cortisol, salivary alpha amylase and HR; P=0.187, P=0.288, P=0.550, respectively). There were no significant differences between the groups for pretreatment values, peak height, difference between pretreatment values and peak height (reactivity) or area under the curve for salivary cortisol, salivary alpha amylase or HR (P>0.05 for all). The results showed that, for men with a moderate level of overweight/obesity who were otherwise healthy, the response of salivary cortisol, salivary alpha amylase and HR to acute psychological stress was not impaired.
authors.affiliation: Centre for Physical Activity and Nutrition ResearchSchool of Exercise and Nutrition Sciences, Deakin University, Burwood, Melbourne, Victoria 3125, AustraliaLivestock and Farming SystemsSouth Australian Research and Development Institute, University of Adelaide, Roseworthy, Adelaide, South Australia 5371, Australia.
authors.forename: S U
authors.initials: SU
authors.lastname: Jayasinghe
authors.affiliation: Centre for Physical Activity and Nutrition ResearchSchool of Exercise and Nutrition Sciences, Deakin University, Burwood, Melbourne, Victoria 3125, AustraliaLivestock and Farming SystemsSouth Australian Research and Development Institute, University of Adelaide, Roseworthy, Adelaide, South Australia 5371, Australia.
authors.forename: S J
authors.initials: SJ
authors.lastname: Torres
authors.affiliation: Centre for Physical Activity and Nutrition ResearchSchool of Exercise and Nutrition Sciences, Deakin University, Burwood, Melbourne, Victoria 3125, AustraliaLivestock and Farming SystemsSouth Australian Research and Development Institute, University of Adelaide, Roseworthy, Adelaide, South Australia 5371, Australia.
authors.forename: C A
authors.initials: CA
authors.lastname: Nowson
authors.affiliation: Centre for Physical Activity and Nutrition ResearchSchool of Exercise and Nutrition Sciences, Deakin University, Burwood, Melbourne, Victoria 3125, AustraliaLivestock and Farming SystemsSouth Australian Research and Development Institute, University of Adelaide, Roseworthy, Adelaide, South Australia 5371, Australia.
authors.forename: A J
authors.initials: AJ
authors.lastname: Tilbrook
authors.affiliation: Centre for Physical Activity and Nutrition ResearchSchool of Exercise and Nutrition Sciences, Deakin University, Burwood, Melbourne, Victoria 3125, AustraliaLivestock and Farming SystemsSouth Australian Research and Development Institute, University of Adelaide, Roseworthy, Adelaide, South Australia 5371, Australia anne.turner@deakin.edu.au.
authors.forename: A I
authors.initials: AI
authors.lastname: Turner
keywords: adiposity; cortisol; hypothalamo–pituitary–adrenal axis; men's health; obesity; stress; sympatho-adrenal medullary system