• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

Card Range To Study



Play button


Play button




Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

172 Cards in this Set

  • Front
  • Back
force x distance (J)
work/time (watts)
refers to the measurement of a work output
refers to the apparatus or device used to measure a specific type of work
was developed more than 100 years ago and remains a popular ergometer in exercise physiology labs today. this type of ergometer is a stationary exercise bicycle that permits accurate measurement of a the amount of work performed
cycle ergometer
how do you determine the distance the wheels of a cycle ergometer travel?
the distance covered by the revolution of the wheel x the number of pedal revolutions
calculation of the work performed while a subject runs or walks on a treadmill is not generally possible when teh treadmill is __
the amount of vertical rise per 100 units of belt travel
percent grade
vertical displacement=__
% grade x distance
Foodstuff + O2 --> ATP + HEAT(what is measured)
direct calorimetry
the process of measuring a persons metabolic rate via the measurement of heat production
direct calorimetry
foodstuff + O2 (what is measured) --> Heat + CO2 + H20
indirect calorimetry
where the direct relationship between O2 consumed and teh amount of heat produced in teh body is used to measure metabolic rate
indirect calorimetry
the most common technique used to measure oxygen consumption today is __
open-circuit spirometry
what does METS stand for?
metabolic equivalent
% net efficiency =
work output/energy expended x 100
three factors that effect exercise efficiency:
work rate, movement speed, muscle fiber type
as work rate increases, exercise efficiency __
there is an __ speed of movement at any given work rate
optimum (inverted parabolic curve)
expressing VO2 as a function fo the body weight
relative VO2
the maintenance of a relatively constant internal environemnt
a steady and unchanging level of some physiological variable
steady state
__ is a steady state, but a steady state is not necessarily __
homeostasis, homeostasis
a series of interconnected components that maintain a chemical or physical parameter of teh body near a constant value
biological control system
biological control systems are composed of 3 elements:
a sensor, a ontrol center, and effectors
a receptor in teh body capable of detecting change in teh variable in question
integrates the strength of teh incoming signal from teh sensor and sends an appropriate message to effectors
control center
receive message from control center and brings about the appropriate repsone to correct teh distrubance
an important class of biological control systems in the body that serves to restore normal values of a variable to maintin homeostasis
negative food back
act to increase the original stimulus
positive feedback
the capability of the control system of correcting a disturabance in homeostasis
gain (control system)
refers to a change in teh sturcture and function of a cell or organ system that results in an improved ability to maintain homeostasis
the improved function of an existing homeostatic system
refers to a system of communication between cells that coordinates cellular activites
cell signalling
occurs when a chemical messenger is produced inside a cell that triggers a signaling pathway within teh same cell that leads to a specific cellular response
intracrine signaling
when cells communicate by cell-to-cell contact, in which teh cytoplasm of one cell is in contact with teh cytoplasm of another through small junctions that connect the two cell membranes
juxtracrine signaling
occurs when a cell produces and releases a chemical messenger into the extracellular fluid that acts upon the cell producing the signal
autocrine signaling
when some cells produce signals that act locally on nearby cells (paracrine signals) to bring about a coordinated response
paracrine signaling
when cells release chemical signals (hormones) into the blood and these hormones are then carried out throughout the body
endocrine signaling
all the collective chemical reactions in the body
__ was the first person to mention exercise
a force acting upon an object to cause a displacement
__ is done when force acts against resistance to produce motion
__ is how much work is done per unit time
one of teh simplest ergometers was developed by teh harvard fatigue lab - __
the harvard step test
why does bodyweight not matter on a cycle ergometer?
because the force is in the fly wheel, not her body
units of energy expenditure:
kcal (calorie)
kind of calorimetry: precise, but expensive and not feasible for exercise research
direct calorimetry
what kind of calorimetry uses a metabolic cart?
you burn __ kcal per L of O2 consumed
1 MET = __ ml/kg/min
how much work is accomplished relative to the energy used
work rate has an __ relationship with efficiency
we use __ when we can't calculate efficincy
lower VO2 = __ economy
homeostasis represents a __ constancy
protein synthesis, phophorylation, energy production, maintenance of appropriate amount of nutrients are all examples of __ control systems
sensors of blood pressure in arteries, sensors of O2 and C02, sensorys of sodium in teh kidney, sensors of tension and stretch in the muscles are examples of __ control systems
an autoimmune destruction of beta cells in teh pancreas that produce insulin
Type I diabetes
when elevated blood glucose and insulin leads to insulin resistance
type II diabetes
what are two examples of adaptation?
heat, altitude
used to combat disrucptoin caused by a stressor
stress protiens
exercise training __ the amount of stress proteins in muscle
synthesis of molecules (use up energy)
anabolic reactions
breakdown of molecules (give off energy)
catabolic reactions
the process of converting foodstuffs into a biologically usuable form of energy (ATP)
__ elements compose __% of the human body
4, 95
the elements that compose the bulk of the human body
hydrogen, carbon, oxygen, nitrogen
why are cells the size they are?
small enough to decrease surface area to transport materials but big enough to hold organelles
the muscle cell membrane is called the __
runners would have more mitochondria than football players because mitochondria need __
the origin of all energy is the __
kind of cellular chemical reaction that requires energy to be added
kind of cellular chemical reaction that releases energy
the breakdown of glucose is a __ reaction
what is an example of a coupled reaction?
RED-OX reactions
reactions in which the liberation of free energy in one reaction being used to "drive" a second reaction
coupled reactions
the process of REMOVING AN ELECTRON from a molecule
the process of ADDING AN ELECTRON to an atom of molecule
oxidation and reduction are __ coupled reactions
very imporant in producing energy (especially for muscle contraction)
metabolic oxidizing agents (gain electorn and H+ from others)
the speed of cellular chemical reactions is regulated by catalysts called __
regulate metabolic pathways in a cell but don't cause reactions
the energy required to initiate chemcial reactions is __
activation energy
enzymes are catalysts because they __ teh activation energy required
the way enzymes lower activation energy is due to __
sturctural characteristics
enzymes operate on a __ model
lock and key
three factors that alter enzyme acitivty
temperature, pH, other enzyme co-factors
broken down into glucose and stored as glycogen in muscle tissue/liver, can be broken down to produce energy, 4 kcals/gram
long carbon chains, stored as triglycerides in fat cells and muscle, broken down by lipolysis into fatty acids and sued by krebs cycle to produce energy, 9 kcals/gram
composed of amino acids, not a great source of energy, many amino acids can be converted inot metabolic intermediates to directly participate in energy production, 4 kcal/hgram
the amino acid __ can be converted to glucose by teh liver
the immediate source of energy for muscular contraction
ATP (adenosine triphosphate)
the production of ATP requires __
the production of ATP is an __ reaction, the breakdown of ATP is an ___ reaction
endergonic, exergonic
the three ways that muscle cells can produce ATP through metabolic pathways
phosphocreatine breakdown, glycolysis, oxidative formation of ATP (krebs cycle, ETC)
glycolysis happens in the __
cytoplasm (sarcoplsam)
the krebs cycle occurs in the __
matrix of the mitochondria
the simplest and most rapid method for producing ATP involves donating a phsophate group and its bond energy form PCR to ADP to form ATP
phosphocreatine system
the enzyme that helps the phosphocreatine breakdown to an inorganic phosphate and creatine
creatine kinase
__ of creatine leads to increased stores of muscle PCr and improved high intensity cycling
20 g/day
a second metabolic pathway capable of producing ATP without the involvement of oxygen
__ participates in both anaerobic and aerobic metabolism
glycolysis breaks down 1 molecule of glucose into __ molecules of __ or __
2, pyruvate or lactate
glycolysis transfers the bond energy in glucose to reform bonds between __ and __
ADP and inorganic phosphates
lactate is the __ form of lactic acid because of the bodies pH
if O2 is available in glycolysis then __ is produced
if O2 is unavailable in glycolysis then __ is produced
a molecule of glucose has __ atoms of carbon
the two sources of glucose and glycogen for glycolysis are __ and __
muscle glycogen, blood glucose
phosphoralation means to __
add a phosphate group
what is the rate limiting enzyme (enzyme that catalyzes glcolysis reaction) in glycolysis?
phosphofructoinase (PFK)
the oxidation (hydrogen removal) of carbohydrates, fats, or proteins using NAD+ and FAD as hydrogen (energy) carriers
krebs cycle
transfers hydrogens (electrons) to the intermembrane space in the mitochondria to generate an energy potnetial necessary for ATP generation
electron transport chain
__ is required as the last step of this process (oxidative phosphorylation) where it accepts __ hydrogen molecules to form water
oxygen, 2
the krebs cycle occur in the __
mitchondrial matrix
the electron transport chain occurs in the __
membranes of the mitochondria
in the krebs cycle, __ becomes __ via glycolysis
glucose, pyruvate
1 molecule of glucose --> __ turns of the krebs cycle
substrates that can be prepared to enter the krebs cycle (3)
glucose, triglycerides, protiens
all substrates enter the kreb cycle at a common place as __, a 2 carbon molecule
the primary function of the krebs cycle
remove hydrogens and energy associated with their bonds; produce CO2
the enzyme that begins the krebs cycle
the rate limiting enzyme of the krebs cycle (controls whether it is on or off)
isocitrate dehydrogenase
stored triglycerides in adipose tissue or muscle cells are broken down by __ into free fatty acids and glycerol
fatty acids of broken down triglycerides can undergo __ for conversion to Acetyl-CoA
beta oxidation
there are __ reactions that chop up fatty acids into Acetyl CoA. the process continues until all of the carbons are converted
proteins are degraded into __ in muscle of released into the blood to provide substrate or intermediates for the krebs cycle
amino acids
protein is less than __% of substrate used during 1 hour of exercise comes from AA's
__ is limited as an energy source because of slow rate of energy release and necessity of protein for muscle/cell function
provides energy during prolonged (>2 hours), low intensity exercise (proteases are activated)
ATP production is possible because of the __ available in reduced hydrogen carriers such as NADH and FADH (from glycolysis, krebs, etc.)
potential energy
NADH and FADH don't directly pass off their H's onto oxygen, they are passed down a series of complexes (cytochromes) that generate a __ between teh intermembrane and matrix space
large protein gradient
the ptoential energy contained in the intermembrane space of teh electorn transport chain travels down the final complex in teh chain (ATP synthatse_ to generate ATP known as the __
chemiosmotic hypothesis
how many total ATP can be generated through by glycolysis with one molecule of glucose
how many total ATP can be generated through by glycolysis with one molecule of glycogen
energy contained in teh ATP molecules produced by aerobic metabolism of glucose/total potential energy in 1 glucose molecule
efficiency of respiration
1 mol of ATP has __ of energy
aerobic ATP production has __% effiency, __% is lost as heat
34, 66
glycolysis proivdes __ ATP's and __ NADH's
2, 2
converting Pyruvate to acetylCoA gnerates __ NADH's
the krebs cycle provides __ GTP, __ NADH, and __ FADH per pyruvate
1, 3, 1
__ occurs in the first few minutes of exercise until aerobic ATP production meets the ATP demand of exercise
oxygen deficit
at the beginning of of exercise there is a __ until respiration increases and teh vasculature shunts blood to active muscles
lag in oxygen uptake
during __ anaerobic ATP supply from PCr and glycolysis meet the ATP demands
O2 lag time
system sinvolved to sustain a steady state of exercise
glycolysis, krebs cycle, ETC
what exceptions to steady state exercise are there?
high heat and humidity, high intensity exercise (>70% VO2 max)
the phenomeneon of the execptions to steady state exercise
what does EPOC stand for?
excess post exercise oxygen consumption
the two components of EPOC
slow and rapid
the component of EPOC in which the body resotres PCr and O2 stores in muscle
rapid component
the component of EPOC in which the body converts lactate back to glucose in the liver (gluconeogensis), provides energy for elevated HR and respiration, increase metabolic rate
slow component
sources of fuel during exercise (4)
lactate, protein, carbs, fat
body fuel sources during exercise (carbohydrates)
muscle glycogen, liver glycogen, blood glucose
what are the oxidative energy systems
krebs cycle, ETC
body fuel sources during exercise (fat)
triglycerides in adipose, triglycerides in muscle tissue, free fatty acids in blood
muscle triglycerides are broken into __ FFA + glycerol
when glycogen stores run low, utilization of __ is reduced because glycolysis produces krebs cycle intermediates (pyruvate) necessary for its oxidation
body fuel sources during exercise (lactate)
cori cycle in liver, muscle and heart lactate
when blood lactate is converted back to glucose in the liver by way of gluconeogensis
cori system
body fuel sources during exercise (protein)
amino acids in blood, amino acids in muscle
provides energy during prolonged (>2) hours, low intensity exercise (proteases are activated)
the ratio fo carbon dioxide producing teh oxygen consumed at a steady state measured with a metabolic cart
respiratory exchange ration (RER)
estimates the percentage of carbs and fat utilization
as intensity of exercise increases, fat burning % __ and carb burning % __
decreases, increases
as intensity increases fuel source shifts from fat to carbs due to (3)
recruitment of fast twitch fibers (high levels of glycolytic enzymes and few mitochondria), increased blood levels of epinephrine (increases glycogen breakdown), increased blood levels of lactate (inhibits fat oxidation)
as exercise intenstiy increases, RER __
as exercise duration increases, % fat burned __ and % carb burned __
increases, decreases
as time increase, RER __
slightly decreases, then levels off
isocitrate is influenced by __ (turns the krebs cycle on) and __ (turns the krebs cycle off)
the rate limiting enzyme of the ETC is __
cytochrome oxidase