Physical activity intensity and older adolescents' stress: The 'STress-Reactivity after Exercise in Senior Secondary EDucation' (STRESSED) 3-arm randomised controlled trial

Jordan J Smith; Mark R Beauchamp; Eli Puterman; Angus A Leahy; Sarah R Valkenborghs; Levi Wade; Frances Chen; David R Lubans

doi:10.1016/j.psychsport.2024.102754

Physical activity intensity and older adolescents' stress: The 'STress-Reactivity after Exercise in Senior Secondary EDucation' (STRESSED) 3-arm randomised controlled trial

Psychol Sport Exerc. 2024 Oct 1:76:102754. doi: 10.1016/j.psychsport.2024.102754. Online ahead of print.

Authors

Jordan J Smith¹, Mark R Beauchamp², Eli Puterman², Angus A Leahy³, Sarah R Valkenborghs³, Levi Wade³, Frances Chen⁴, David R Lubans⁵

Affiliations

¹ Centre for Active Living and Learning, College of Human and Social Futures, University of Newcastle, Callaghan, Australia; Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia. Electronic address: [email protected].
² School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada.
³ Centre for Active Living and Learning, College of Human and Social Futures, University of Newcastle, Callaghan, Australia; Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia.
⁴ Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
⁵ Centre for Active Living and Learning, College of Human and Social Futures, University of Newcastle, Callaghan, Australia; Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia; Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.

PMID: 39362353
DOI: 10.1016/j.psychsport.2024.102754

Abstract

Objectives: Late adolescence (15-19 years) is a period of heightened susceptibility to stress, but regular physical activity may attenuate reactivity to stressors. We aimed to explore the effects of physical activity intensity on older adolescents' stress-reactivity and self-reported mental health.

Design and methods: Three-arm randomised controlled trial in New South Wales, Australia (April-June 2021). Thirty-seven older adolescents (16.1 ± 0.2 years, 59.5 % female) were randomised to: i) non-active control (CON), ii) light-intensity physical activity (LPA), or iii) moderate-to-vigorous-intensity physical activity (MVPA). Physical activity groups participated in 2 x 20-min sessions/week for 6 weeks. Salivary cortisol (sCort) reactivity to induced stress was assessed using the Trier Social Stress Test for Groups and quantified as area under the curve (sCort_AUC; Primary outcome). Secondary outcomes included peak cortisol (sCort_Peak), subjective-reactivity, perceived stress, and non-specific psychological distress. Group differences were assessed using multiple linear regression and quantified using Cohen's d.

Results: No statistically significant effects were observed for sCort_AUC or sCort_Peak and the pattern of effects for subjective-reactivity was inconsistent. Effects for self-reported mental health were also non-significant (p > .05 for all) but of meaningful magnitude, favouring LPA and MVPA over CON (d's = -0.38 to -0.54). Delivery fidelity was high, satisfaction was moderate-to-high, and there was no evidence of harm. However, recruitment, retention for sCort measures, and adherence were lower than expected.

Conclusion: Suboptimal recruitment, retention, and adherence limited our ability to conclude on the effect of physical activity intensity on older adolescents' sCort-reactivity to induced stress. We observed potentially meaningful effects on self-reported mental health for both physical activity conditions, which could be confirmed in a future powered trial.

Keywords: Cortisol; Fitness; Intervention; School; Youth.