Chapter 3: Bioenergetics of Exercise and Training Flashcards
flow of energy in a biological system, process that converts macronutrients into usable forms of energy to perform work
bioenergetics
what is metabolic specificity of training?
the concept that appropriate intensities and rest intervals can permit the selection of specific primary energy systems during training for specific athletic events
metabolism
total of all the catabolic and anabolic reactions in a biological system
catabolism
breakdown of large molecules into smaller molecules with the release of energy
anabolsim
synthesis of a large molecule from smaller molecules that requires energy released from catabolic reactions
energy-releasing reactions that are generally catabolic
exergonic reactions
reactions that require energy, include anabolic processes and the contraction of muscle
endergonic reactions
molecule that allows the transfer of energy from exergonic to endergonic reactions
ATP
hydrolysis
the breakdown of one molecule of ATP to yield energy
3 basic energy systems to replenish ATP
phosphagen
glycolysis
oxidative
processes that do not require oxygen
anaerobic
processes that depend on oxygen
aerobic
2 anaerobic energy systems that occur in the sarcoplasm of the muscle cell
phosphagen and glycolytic systems
2 aerobic mechanisms that occur in the mitochondria of muscle cells and require oxygen
kreb’s cycle and oxidative system
what is the only macronutrient that can be metabolized for energy without the direct involvement of oxygen and critical during anaerobic metabolism?
carbohydrate
energy system that provides ATP primarily for short term, high intensity activities and is highly active at the start of all exercise regardless of intensity
phosphagen system
which muscle fiber type contains higher concentrations of CP and can therefore replenish ATP faster through the phosphagen system during anaerobic explosive exercise?
type II fast twitch
energy system that uses the breakdown of carbohydrates to resynthesize ATP (either glycogen stored in the muscle or glucose delivered in the blood)
glycolysis
anaerobic glycolysis (fast)
when pyruvate is converted to lactate, ATP resynthesis occurs at a faster rate but is limited in duration
aerobic glycolysis (slow)
when pyruvate is shuttled into the mitochondria to undergo the kreb’s cycle, ATP resynthesis rate is slower but can occur for a longer duration if exercise intensity is low enough
true or false: lactate is the cause of muscle fatigue
false
metabolic acidosis
process of an exercise induced accumulation of H+ that may be responsible for much of the fatigue that occurs during exercise
causes fatigue by reducing pH, inhibiting glycolytic reactions, and interfering with the muscle’s excitation-contraction coupling
H+
what is the cori cycle?
process where lactate is transported in the blood to the liver to be converted to glucose
end result of glycolysis
pyruvate
A series of reactions that continues the oxidation of the substrate from glycolysis and produces 2 ATP molecules is known as
Krebs cycle
what energy system uses carbs and fats as the primary source of ATP at rest and during low intensity activities?
oxidative system
what is lactate threshold?
the exercise intensity at which blood lactate begins an abrupt increase above the baseline concentration, increased reliance on anaerobic mechanisms
what is the typical lactate threshold for untrained individuals?
50-60% of maximal oxygen uptake