Effects of Moderate Exercise and Cyclic Sighing on Stress, Cognition and Physiological Markers in Young Adults

This study investigates the effects of moderate physical exercise and cyclic sighing (breathing training) on stress, cognition, and physiological markers in young adults. It is a randomized cross-over trial with two interventions. Each participant will take part in two intervention sessions: 1. Moderate-intensity physical activity (PA): 15 minutes of stationary cycling at 65-75% of maximum heart rate (HRmax). 2. Breathing training (CS): 15 minutes of cyclic sighing, a technique involving inhaling, pausing briefly, taking a deeper breath, and exhaling slowly. A one-week washout period between sessions is planned to minimise carry-over effects and to ensure participants' physiological state is similar before the next session. During this week, participants will wear Polar Ignite wrist-worn devices to monitor physical activity and sleep. A total of 30 participants (you adults) will be enrolled. Measurements performed before and after each intervention include: * EEG using Emotiv EPOC Flex Gel (32-channel device): 2 minutes with eyes open, 2 minutes with eyes closed, during the interventions, and while performing cognitive test (N-back). * Heart rate variability (HRV) using the Polar H10 sensor. * SUDS - Subjective Units of Disress Scale for perceived stress. * N-back test for cognitive performance using Emotiv App. * Blood pressure (systolic and diastolic) and heart rate. * Pain threshold measured with a dolorimeter. * PANAS-SF - Positive and Negative Affect Schedule. Baseline questionnaires completed by participants the day before the study: * PSS-10 - Perceived Stress Scale (Cohen, Kamarck, Mermelstein). * MAAS - Mindful Attention Awareness Scale * Psychological well-being - short version * Mini-COPE - Coping with Stress Inventory * Sleep quality and average sleep duration * Chronotype questionnaire (morningness-eveningness) * GPAQ - Global Physical Activity Questionnaire * Pittsburgh Sleep Quality Index The study aims to understand how brief interventions li