Flashcards in Chapter 5 - Energy For Muscular Activity Deck (69):
what are the learning objectives of energy for muscular activity?
1) to develop an awareness of the basic chemical process that the body uses to produce energy in the muscles
2) to develop an understanding of the body's three main energy systems
3) to introduce the effect of training and exercise on the energy system
energy in the human body is derived from the breakdown of complex nutrients such as? (3 things)
carbohydrates, fats and proteins
the end result of the breakdown of complex nutrients such as carbs, fats and proteins is production of the _________ ________ (ATP) molecule
Adenosine Triphosphate molecule
ATP provides ______ necessary for body functions
can the system work without ATP? why?
no because it maintains the body temperature and it aids in digestion
another name for ATP breakdown is?
ATP + H2O = ___ + Energy + P
what are the 3 steps to ATP breakdown?
1) Hydrolysis of the unstable phosphate groups of ATP molecule by H2O
2) Phosphate molecule (P) is released from ATP (ATP--> ADP)
3) Energy is released (38-42kJ, or 9-10kcal/mol ATP)
Molecule + P = Energy for muscle contraction
1) Energy released by ATP turnover can be used by the body when a free P group is transfered to another molecule
ADP + Energy + P = ATP
Steps to ATP resynthesis
1) Initial stores of ATP in the muscles are used up very quickly and ATP must be regenerated
2) ATP is formed by recombination of ADP and P
Regeneration of aTP requires energy (this energy comes from breakdown of food molecules)
What are the 3 energy systems?
1) the high energy phosphate system
2) the anaerobic glycolytic system
3) the aerobic oxidative system
What is the primary energy source of the high energy phosphate system?
stored ATP, CP (Creatine Phosphate)
What is the duration of activity for the high energy phosphate system?
what sporting events involve the high energy phosphate system?
weight lifting, high jump, long jump, 100m run, 25m swim
What are the advantages to the high energy phosphate system?
produce very large amount of energy in a short amount of time
what are the limiting factors of the high energy phosphate system?
initial concentration of high energy phosphates (ATP, CP)
what are the 2 ways of training the high energy phosphate system?
1) interval training
2) sprint training
list 4 points about interval training.
- 20% increase in CP (creatine phosphate) stores
- no change in ATP stores
- increase in ATPase function (ATP ADP+P)
- increase in CPK (creatine phosphokinase) function (NB: CPK breaks down CP molecule and allows ATP resynthesis)
list 2 points about sprint training.
- increase in CP stores up to 40%
- 100% increase in resting ATP stores
What is the primary energy source of the Anaerobic Glycolytic System?
Stored glycogen, blood glucose
What is the duration of activity for the Anaerobic Glycolytic System?
what sporting events involve the Anaerobic glycolytic system?
800m run, 200m swim, downhill ski racing, 1500 speed skating
what are the advantages to the anaerobic glycolytic system?
ability to produce energy under conditions of inadequate oxygen
what are the limiting factors of the anaerobic glycolytic system?
lactic acid build up, H+ ions build up (decrease of pH)
a biochemical process that releases energy in the form of ATP from glycogen and glucose
what type of process is glycolysis?
what are the 2 products of glycolysis (per molecule of glycogen)?
- 2 molecules of ATP
- 2 molecules of pyruvic acid
what is the by-product of glycolysis?
2 molecules of lactic acid
- the exercise intensity level at which lactic acid begins to accumulate within the blood
What is the term for the point during exercise where the person begins to feel discomfort and burning sensation in their muscles?
_____ acid is used to store pyruvate and hydrogen ions until they can be processed by the aerobic system
the anaerobic glycolytic system starts when...
- the reserves of high energy phosphate compounds fall to a low level
- the rate of glycolysis is high and there is a buildup of pyruvic acid
when the body goes into shock it produces ______?
when there is a high level of lactic acid in the body what happens?
the anaerobic threshold doesn't allow function
the primary source of substrates for the anaerobic energy system is ________.
primary dietary source of glucose
primary energy fuels for, brain, muscles, heart and liver
what is the effect of training on the Anerobic Glycolytic system?
rate of lactic acid accumulation is decreased in the trained individual
the rate of lactic acid accumulation can be decreased by what 2 things?
1) reducing the rate of lactate production
2) increasing the rate of lactate elimination
what is the way to reduce the rate of lactate production?
increase in the effectiveness of the aerobic oxidative system
what is the way to increase the rate of lactate elimination?
- increased rate of lactic acid diffusion from active muscles
increased muscle blood flow
increased ability to metabolize lactate in the heart, liver and in non-working muscle
what is the primary energy source of the aerobic oxidative system?
glycogen, glucose, fats and proteins
what is the duration of activity for the aerobic oxidative system?
what sporting events involve the aerobic oxidative system?
walking, jogging, swimming, walking up stairs
what are the advantages of the aerobic oxidative system?
large output of energy over a long period of time, removal of lactic acid
what are the limiting factors of the aerobic oxidative system?
long function, maximum blood flow, oxygen availability, excess energy demands
what is the most important energy system in the body?
the aerobic oxidative system
in the aerobic oxidative system, do blood lactate levels remain relatively low or relatively high?
relatively low (3-6mmol/L blood)
little energy power houses
what are the 2 pathways of the oxidative phosphorylation system?
Krebs cycle and Electron Transport Chain
oxidative phosphorylation system
biochemical process used to resynthesize ATP by combing ADP and P in the presence of oxygen
where does oxidative phosphorylation system take place?
in the mitochondria (contains enzymes, co-enzymes)
what is the energy yield from 1 molecule of glucose?
36 ATP molecules
Energy yield from 1 molecule of fat is up to?
169 ATP molecules
what are the by-products of the oxidative phosphorylation system reaction?
carbon dioxide, water
lactic acid is taken to the liver to metabolized back in pyruvic acid and then glucose
the power of the aerobic system
evaluated by meauring the maximal volume of oxygen that can be consumed per kilogram of mass in a given amount of time (this measure is called aerobic power or VO2 max (ml/min/kg)
What are 3 factors that contribute to high aerobic power?
1) arterial oxygen content (CaO2)
2) Cardiac Output (Q = HR x stroke volume)
3) Tissue oxygen extraction (a-vO2, diff)
What are the 2 substrates for the aerobic system?
Carbohydrates (glycogen and glucose) and fats (triglycerides and fatty acids)
list 5 food items you could find fat in.
dairy products, meats, table fats, nuts and some vegetables
what is the bodies largest store of energy?
other than energy storage what are 3 other major functions fat serves to do.
1) cushion the vital organs
2) protect the body from cold
3) serve to transport vitamins
how many calories is 1 gram of fat equal to?
9 calories of energy
how many calories is 1 gram of protein equal to?
how many calories is 1 gram of carbohydrate equal to?
what is the most effective method of training?
what does endurance training do? (list 4)
- increases vacularization within muscles
- increases number and size of mitochondria within the muscle fibres
- increases the activity of enzymes (Krebs cycle)
- preferential use of fats over glycogen during exercise