EVALUATION OF PHYSIOLOGICAL AND PSYCHOLOGICAL STRESS RESPONSES ON ACTIVITY-PERMISSIVE WORKSTATIONS: A RANDOMIZED CONTROLLED TRIAL

Abstract

Background: Activity-permissive workstations (APWs), such as treadmill and standing desks, offer a potential strategy to reduce sedentary behavior and improve well-being. However, it remains unclear whether light-intensity activity during cognitively demanding or stressful tasks alters physiological or psychological stress responses.Methods: In this preregistered 2 (TSST vs. non-TSST) × 3 (sitting, standing, walking) laboratory-based experimental study, 157 adults (Mage = 29.8 ± 11.1 years) completed the Trier Social Stress Test (TSST) or a control task while seated, standing, or walking on a treadmill desk for approximately 85 minutes. Psychological (perceived stress, affect), physiological (heart rate, heart rate variability, blood pressure, cortisol), and behavioral (speech, math) responses were assessed across baseline, reactivity, and recovery phases. Linear mixed-effects models with spline-coded time captured reactivity (T2–T3; cortisol T3–T4) and recovery (T3–T5; cortisol T4–T5) slopes, adjusting for baseline, age, gender, BMI, session time, sleep, caffeine, and medication use. Results: The TSST elicited robust psychological and physiological stress responses across all conditions (ps < .001). Contrary to our hypotheses, workstation type did not significantly affect reactivity or recovery for stress, affect, blood pressure, heart rate, or cortisol. Walking participants reported higher overall positive affect (p = .013), and post-session ratings indicated that walking was more enjoyable than sitting (p = .02) and more comfortable than standing (p = .002). HRV was lower and flatter in active conditions, consistent with posture-related vagal withdrawal rather than stress modulation. Task performance did not differ across workstations. Conclusions: Light-intensity movement during an acute stressor did not attenuate stress responses but also did not amplify them, while preserving task performance and improving comfort and enjoyment. These findings suggest that low-intensity movement can be incorporated into cognitively demanding contexts without amplifying stress and may enhance long-term feasibility and adherence to active workstation use.