Energy, fitness and training
What is the typical duration limit for the ATP-PC system during high-intensity activity?
Approx 10secs
What is the approximate duration limit for the lactic acid system during maximum effort?
60-75 secs
Which nutrient is the preferred fuel source for the aerobic system at rest or during very low-intensity activity?
Fats
Which type of muscle fiber produces high force and is utilized for rapid, explosive movements?
Fast twitch fibres
The concept that all three energy systems work simultaneously to provide ATP is known as energy system _____.
Interplay
How much rest is required to almost totally replenish muscular stores of phosphocreatine?
What physiological sensation marks the accumulation of lactate and the onset of muscle fatigue?
A burning sensation in the working muscles.
At what exercise intensity (as a percentage of maximum heart rate) does glycogen become the preferred fuel source over fat?
60%
What is the typical number of muscle fibers per motor unit in fast-twitch muscles?
300-800
Define VO2 Max
The maximum volume of oxygen that the body is capable of gathering and utilizing per minute.
Term: Alactate system
Definition: An alternative name for the ATP-PC system, indicating that no lactate is produced during energy release.
The process where the liver converts lactate back into glucose requires ATP from which energy system?
Aerobic energy system
Term: Oxidative system
Definition: An alternative name for the aerobic energy system, reflecting its use of oxygen to produce ATP.
Which sub-type of fast-twitch fiber is considered partially aerobic and can adapt through endurance training?
Fast twitch (a)
Term: Oxygen Deficit
Definition: The difference between the oxygen required for a work rate and the oxygen actually consumed during the start of exercise.
Which energy system uses glucose from the breakdown of glycogen to produce ATP without oxygen?
Lactic acid
Which energy system is the preferred source for low-to-moderate intensity activities over extended periods?
Aerobic
Which type of muscle fiber is best suited for endurance activities due to its fatigue resistance?
Slow twitch fibres
Which muscle fiber type is totally anaerobic and produces the highest amount of force?
Fast twitch (b)
What is the physiological term for the state where oxygen supply perfectly meets oxygen demand during sub-maximal exercise?
Steady state
What is the specific by-product of anaerobic glycolysis?
Lactate
What are the two primary by-products of the aerobic energy system?
Water and CO2
Muscle fibers are arranged into groups controlled by a single neuron called _____ _____.
Motor units
According to muscle recruitment patterns, which fiber type is activated first for any muscular contraction?
Slow twitch
What does the acronym EPOC stand for?
Excess post-exercise oxygen consumption.