The Respiratory Exchange Ratio (RER) (CO2 production/O2 uptake) increase with the exercise intensity and measured under steady state conditions is commonly used to indirectly determine the relative contribution of carbohydrate and lipids to overall energy expenditure (Simonson and DeFronzo, 1990; Pendergast et al.
What is the relationship between exercise intensity and heart rate and respiratory rate?
The more the heart beats, the more breathing occurs. As the heart beats faster, it uses more energy and sends more oxygen to the body. If a person is exercising the oxygen is used very quickly in order to provide the muscles with needed energy to move. Thus the heart beats faster to pump more oxygen to the muscles.
How does exercise affect your respiration?
The lungs bring oxygen into the body, to provide energy, and remove carbon dioxide, the waste product created when you produce energy. The heart pumps the oxygen to the muscles that are doing the exercise. When you exercise and your muscles work harder, your body uses more oxygen and produces more carbon dioxide.
How does exercise affect fuel selection?
Fuel selection during exercise is dependent on a variety of factors and the intensity of exercise is a major determinant in fuel selection. The R-value is higher at high work intensities, indicating an increased relative contribution of CHO to total metabolism with increasing work intensity.
What are the factors affecting RQ?
Most of the time, however, energy consumption is composed of both fats and carbohydrates. The approximate respiratory quotient of a mixed diet is 0.8. Some of the other factors that may affect the respiratory quotient are energy balance, circulating insulin, and insulin sensitivity.
How does exercise intensity affect RER?
The RER decreases with exercise duration, dietary fat intake, age, VO2max, and percentage of type I muscle fibers, and increases with dietary carbohydrate intake, exercise intensity, male sex, and carbohydrate intake before and during exercise.