This energy system provides immediate energy for about 1–10 seconds using stored ATP and phosphocreatine.
What is the ATP-PC (phosphagen) system?
This macronutrient is the body’s preferred source of energy during high-intensity exercise.
What are carbohydrates?
This is the number of times the heart beats per minute.
What is heart rate?
This is the amount of air inhaled or exhaled in a normal breath.
What is tidal volume?
This principle states that the body adapts to the demands placed on it.
What is the principle of specificity?
This byproduct accumulates during anaerobic glycolysis and is associated with muscular fatigue.
What is lactate (lactic acid)?
This nutrient provides 9 kcal per gram and is primarily used during low-intensity exercise.
What are fats?
This is the volume of blood pumped by the heart per beat.
What is stroke volume?
This is the maximum amount of air that can be forcibly exhaled after a full inhalation.
What is vital capacity?
This principle involves gradually increasing training load to continue improving fitness.
What is progressive overload?
This energy system predominates during activities lasting 30 seconds to 2 minutes and does not require oxygen.
What is the anaerobic glycolytic (lactic acid) system?
This storage form of glucose is found in the liver and muscles.
What is glycogen?
This is calculated by multiplying heart rate and stroke volume.
What is cardiac output?
This gas is exchanged in the alveoli and transported by hemoglobin.
What is oxygen?
This type of muscle fiber is fatigue-resistant and suited for endurance activities.
What are Type I (slow-twitch) fibers?
This process occurs in the mitochondria and produces the greatest yield of ATP using oxygen.
What is aerobic respiration?
This index ranks carbohydrates based on how quickly they raise blood glucose levels.
What is the glycemic index?
This adaptation from endurance training increases the heart’s efficiency by lowering resting heart rate.
What is increased stroke volume (or cardiac hypertrophy)?
This term describes the total volume of air breathed per minute.
What is minute ventilation?
This adaptation increases the number of capillaries surrounding muscle fibers.
What is capillarization?
During prolonged exercise, this mechanism allows fats to become the primary fuel source as glycogen stores deplete.
What is increased beta-oxidation (fat metabolism shift)?
This process describes the conversion of non-carbohydrate sources like amino acids into glucose.
What is gluconeogenesis?
This is the difference between oxygen content in arterial and venous blood during exercise.
What is the arteriovenous oxygen difference (a-vO₂ diff)?
This law explains gas exchange based on pressure gradients between alveoli and blood.
What is Fick’s Law (of diffusion)?
This hormonal response to resistance training promotes muscle growth and protein synthesis.
What is increased testosterone (or anabolic hormone response)?