Bioenergetics

Bioenergetics

The flow of energy in a biological system.

Catabolism

The breakdown of large molecules into smaller molecules.

Anabolism

The synthesis of larger molecules from smaller ones.

Exergonic reaction

An energy-releasing action, generally catabolic.

Endergonic reaction

Includes all anabolic processes and muscle contraction.

Macronutrient conversion

Process of converting macronutrients into usable forms of energy.

Metabolism

Total of all chemical reactions in the body.

ATP (Adenosine triphosphate)

A molecule that allows for the transfer of energy from catabolic to anabolic reactions.

Phosphagen system

An anaerobic and anabolic energy system used during short-term, high-intensity activities.

Type II fibers

Muscle fibers that contain a higher concentration of creatine phosphate compared to type I fibers, enabling faster ATP replenishment.

Creatine phosphate

A molecule that helps to replenish ATP during high-intensity exercise.

Glycolysis

The breakdown of carbohydrates to synthesize ATP, occurring in the sarcoplasm.

Pyruvate

The end product of glycolysis, which can be converted to lactate or enter the Kreb cycle.

Kreb cycle

A series of reactions that generate energy through the oxidation of Acetyl-CoA.

Oxidative system

An aerobic energy system that primarily generates ATP in the mitochondria.

Substrates at rest

70% fats and 30% carbohydrates are used at rest for energy.

Lactate threshold

The point at which lactate begins to accumulate in the blood, indicating increased reliance on anaerobic mechanisms.

Onset of blood lactate accumulation

Occurs when there is an abrupt increase in lactate concentration, typically at 4 millimoles.

Substrate depletion

The reduction of energy substrates like ATP and creatine phosphate during exercise.

Glycogen depletion

The reduction of glycogen stores in response to exercise intensity.

Oxygen uptake (O2 consumption)

A measure of the body's ability to uptake and use oxygen during physical activity.

Oxygen deficit

The period during which the anaerobic system compensates for energy demands before reaching steady state.

EPOC (Excess Post-exercise Oxygen Consumption)

The elevated metabolism following exercise that compensates for oxygen deficit.

Heart rate reserve

The difference between predicted maximum heart rate and resting heart rate.

Resistance training

Heavy training aimed at increasing muscular strength and endurance.

Metabolic specificity of training

Adapting training programs to specifically target energy systems relevant to athletic events.

High-intensity interval training (HIIT)

A training method involving brief, repeated bouts of high-intensity exercise with rest periods.

Combination training

Integrating aerobic endurance training into anaerobic athletes' routines to improve recovery.

ATP resynthesis

The process of replenishing ATP after it has been used during exercise.

Protein oxidation

The breakdown of protein into amino acids for energy, although it's not a significant energy source.

Free fatty acids (FFA)

Fatty acids released from triglycerides for energy production.

Beta oxidation

The metabolic process of breaking down free fatty acids to generate Acetyl-CoA.

Energy system capacity

The total amount of ATP that can be produced over time, dependent on intensity and duration.

Anaerobic mechanisms

Energy systems that do not require oxygen, typically utilized during high-intensity exercise.

Intermittent recovery periods

Rest breaks during high-intensity exercise that allow for partial recovery.

Intake of carbohydrates post-exercise

Recommended intake of 0.7-3g of carbohydrates per kg of body weight every two hours after exercise.

4 millimoles of lactate

The threshold level of lactate accumulation where performance may be compromised.

Intensity of activity

The primary factor influencing the contribution of energy systems to ATP production.

Duration of activity

The secondary factor that influences ATP production across different energy systems.

Creatine phosphate depletion

A significant decrease (50-70%) of creatine phosphate levels within 5 seconds of high-intensity exercise.

Cardiopulmonary adaptations

Changes in the cardiovascular and respiratory systems due to high-intensity interval training.

Nutritional recovery strategy

Post-exercise carbohydrate ingestion to aid in glycogen replenishment.

Training adaptation

Physiological changes that occur in response to training, improving performance.

Hydrolysis of ATP

The biochemical reaction in which ATP is broken down to release energy.

Mitochondrial function

The ability of mitochondria to efficiently produce ATP during aerobic metabolism.

Total ATP production

The total amount of ATP generated by metabolic processes over time.

Duration of exercise

The length of time an exercise session is performed, affecting energy system contributions.

Max rate of ATP production

The highest rate at which ATP can be synthesized by an energy system.

Glucose oxidation

The metabolic process that utilizes glucose for energy production.

Exercise at steady state

A consistent level of exertion where oxygen supply meets energy demand.