The influence of different types of heat stress on affective and behavioural processes in healthy young men (aged 18–40).
Conditions
Interventions
Group 1: A repeated-measures, between-groups design was employed, comprising one control group (CG) and two experimental groups: a passive heat stress group (passive group) and a combined heat stress
BMI: M = 24.25, SD = 2.34). All participants were regularly physically active (intensive minutes per week: 61.00, SD = 40.24
moderate minutes per week: 62.77, SD = 30.15). Exclusion criteria included heat acclimatisation or recent exposure (within the last 30 days) to warmer climates for more than five consecutive days. Par
Sponsors
Universität Salzburg
Eligibility
Sex/Gender
Male
Age
18 Years to 40 Years
Inclusion criteria
Inclusion criteria: Men aged between 18 and 40
Exclusion criteria
Exclusion criteria: Due to the methodology: - Heat-acclimatised participants (having spent more than 5 days in a warmer climate zone within the last 30 days) (Gibson et al., 2015) Due to physical exertion and heat stress (Westwood et al., 2021; Périard et al., 2021): - Health conditions that preclude physical exertion within the context of the study (e.g. acute illnesses, fever or other flu-like infections within the last 7 days prior to the start of the study), orthopaedic conditions, injuries to the musculoskeletal system (muscles, bones, joints or tendons) within the last three months. - Systemic diseases or other known pathologies affecting the organs: heart, lungs, kidneys, stomach, spleen, liver and intestines - High blood pressure, cardiovascular complaints, any circulatory problems experienced in recent years - Long Covid - Type 2 diabetes - Neurological or mental health conditions of any kind - Currently undergoing medical or psychotherapeutic treatment - Pollen allergy and associated shortness of breath - Current sunburn - Burns - Use of medication (e.g. antihistamines, painkillers) - Sickle cell anaemia (hereditary abnormality of red blood cells) - Hypohidrosis (insufficient secretion of sweat) - Malignant hyperthermia (a rare, life-threatening rise in body temperature that can occur in people taking certain muscle relaxants) - Sympathectomy (a form of surgical nerve block) - Any discomfort experienced during sauna sessions Due to the temperature-regulating pill: - Pacemakers or other implanted medical devices - Bowel conditions that may lead to an obstruction of the digestive tract, - Gastroparesis (a stomach condition in which food is digested more slowly than normal) - People with diverticula - Surgical procedures in the gastrointestinal tract - Swallowing difficulties (gag reflex) - Exposure to electromagnetic fields (particularly magnetic resonance imaging – MRI) in the days following participation in the study
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Questionnaires and scales Fatigue as Rating-of-fatigue (ROF) and subjective vitality were assessed using a 11-point scale 9,10. Both are 1-item scales and therefore suitable to measure moment-to-moment changes during the heat stress exposures. The ROF ranges from 0 = not fatigued at all to 10 = total fatigue and exhaustion 10. Subjective vitality in the present was assessed by the SVS-GM1 (“I feel vital, full of drive and spirited”) from 0 = not true at all to 10 = totally true and as well by the SVS-BM3 pre and post experiment via electronic questionnaire 9,11. The affective state was measured using the Positive and Negative Affect Schedule (PANAS) 12,13. Each item describes a positive or negative affective state (e.g., enthusiastic, inspired, upset, scared). The subject rate from 1 = not at all to 5 = extremely how much the item correlates with their affective state in the present moment 12. The PANAS was measured pre- and post the intervention. Balloon Analogue Risk Task (BART) BART is a computerised task displaying a balloon on a screen 18. Pressing the 'right arrow' key inflates the balloon with each keystroke and adds five points to the participant’s account. At some point, the balloon may burst; if it does, the points from the current trial are lost. The participants can voluntarily inflate the balloon until one decides to collect the points. The goal is to collect as many points as possible. The goal variable for the analysis was the adjusted average pump score (AAP). Typically, the BART consists of 30 trials, with a maximum of 128 pumps possible before the balloon bursts, making 64 pumps per trial the theoretical optimal number. Hence, the probability to explode increases with every pump until it is 1. The participants received no information about the actual possible pumps or breaking points 18. Due to three tests within two hours, it was decided to halve the theoretical number of pumps to 64 and utilise just 20 trials, to minimise learning or habituati | — |
Secondary
| Measure | Time frame |
|---|---|
| Questionnaires and scales Thermal sensation (TS) is a measure of subjective perception, capturing whether an individual feels hot, cold, or neutral. Based on this perception, individuals reflect the physiological and psychological satisfaction with their thermal environment, a concept referred to as thermal comfort (TC) 6. In a series of studies, TC and TS scales were validated for non-uniform, transient conditions (e.g., experiencing a cold stimulus as comfortable after sauna exposure) 7. The scale was used as a 21-point version from -10 to +10. The combination of TS and TC provides a comprehensive subjective measure for capturing dynamic changes in thermal environments 8. Over the course of the experiment, the participants were expected to experience transient and/or stable temperature conditions, starting with rising body temperatures in the sauna, stabilising during walking in the combined group, or slightly decreasing temperatures in the passive group after sauna exposure. Impulsiveness traits were self-reported with the Short-Urgency-Premeditation-Perseverance-Sensation Seeking-Positive Urgency (SUPPS-P) scale 14,15. The questionnaire was originally designed to quantify four dimensions of impulsivity: negative urgency (tendency to behave impulsive while experiencing intense negative emotions or stress), lack of premeditation (tendency to act without thinking of the consequences), lack of perseverance (inability to remain focused on tasks), and sensation seeking (tendency to seek out novel and thrilling experiences) 14. Later, Cyders, et al. 16 added the complementary positive urgency dimension (tendency to behave impulsive while experiencing intense positive emotions or excitement). The SUPPS-P consists of 20-items, and each is rated on a 4-point scale from 1 = agree strongly to 4 = disagree strongly. It is reliable and valid compared to the elaborate UPPS-P version. The minimal losses in accuracy are balanced by significant time savings 15. The traits of ri | — |
Countries
Austria
Contacts
Public ContactJannic Wälde
Universität Salzburg
Outcome results
None listed