Changes in Energy Expenditure in Response to Physical Activity in Healthy Adults

Medical University of Bialystok20 enrolled

Overview

This study investigates how short, high-intensity body-weight exercises affect energy use in healthy young adults. The focus is on resting metabolic rate (RMR), total energy expenditure (TEE) and excess post-exercise oxygen consumption (EPOC), measured with a portable indirect calorimetry system (COSMED K5). Participants will be 14 volunteers, seven women and seven men aged 18 to 30 years, recruited from the academic community of the Medical University of Białystok. Each subject will first undergo basic screening, including ECG, blood pressure, and body composition. Measurements will be taken in three phases. In the resting phase, RMR will be recorded after fifteen minutes of quiet sitting. In the exercise phase, participants will perform squats, burpees, or a plank for one minute at maximum effort or sustained position while energy use is continuously monitored. In the recovery phase, EPOC will be measured immediately after exercise to capture short-term changes. Oxygen uptake, ventilation, heart rate, and oxygen saturation will be tracked throughout the session. Environmental conditions such as room temperature and humidity will be standardized, and participants will avoid caffeine, alcohol, and heavy physical activity at least 24 hours before testing. The main aim is to determine whether even one minute of exercise can meaningfully alter EPOC steady state parameters, and to compare the energy cost of different exercise types. The data will be analyzed in relation to anthropometric variables and cardiopulmonary function. Results are expected to improve understanding of short-term energy dynamics and may support more precise recommendations in pulmonary rehabilitation, cardiology, sports medicine, and nutrition. By providing reliable measurements of caloric cost in simple exercises, the study can help design safer and more effective training, rehabilitation, and weight control programs.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Physical Activities

physical activityDIAGNOSTIC_TEST

Participants perform short, body-weight exercises including squats, burpees, or plank while wearing a portable indirect calorimetry system (COSMED K5). Each activity lasts one minute and is carried out at maximum effort or sustained position. Energy expenditure, oxygen consumption, ventilation, and vital signs are continuously recorded during and immediately after the activity. Measurements are compared with resting metabolic rate obtained before and excess post-exercise oxygen consumption obtained after exercise to assess the acute impact of physical activity on energy use in healthy young adults.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 30 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age 18-30 years * Healthy volunteers without chronic diseases * Normal resting ECG (regular sinus rhythm, 60-90 bpm) * Normal blood pressure according to ESC guidelines * Ability and willingness to provide written informed consent Exclusion Criteria: * Chronic diseases or musculoskeletal injury within the past 6 months * Use of tobacco or nicotine products within the past 6 months * Blood donation \>20 mL (except diagnostic) within the past 6 months * Use of narcotics, sedatives, or dietary supplements (e.g., creatine) within the past 2 weeks * Active infection, fever, or acute illness at the time of study * Inability to comply with study instructions (dietary restrictions, abstinence from alcohol/caffeine, exercise restrictions)

Outcomes

Primary Outcomes

Differences Between Pre- and Post-exercise Energy Expenditure Measurement

Resting metabolic rate (RMR) will be measured in kcal/min using the COSMED K5 portable indirect calorimetry system. Each participant will undergo a baseline measurement after 15 minutes of seated rest. Immediately following one minute of physical activity (squats, burpees, or plank) with continuous measurement of energy expenditure, then during restitution EPOC will be measured (in lO₂ or kcal) until values stabilize. The primary outcome is the difference between post-exercise energy expenditure and baseline, reflecting the acute impact of short-duration, high-intensity activity on energy metabolism in healthy young adults.

Time frame: Baseline and immediately post-exercise (within 10-15 minutes).

Secondary Outcomes

Total Energy Expenditure (TEE) During Exercise

Resting metabolic rate (RMR) will be measured in kcal/min using the COSMED K5 portable indirect calorimetry system. Each participant will undergo a baseline measurement after 15 minutes of seated rest. Immediately following one minute of physical activity (squats, burpees, or plank) with continuous measurement of energy expenditure, then during restitution EPOC will be measured (in lO₂ or kcal) until values stabilize. The secondary outcome is a measure of energy expenditure during one minute of high-intensity activity in healthy young adults.

Time frame: From the beginning to the end of performing the exercise (1 minute).