Exercise Science test 2 Flashcards
What is exercise physiology?
Study of the functional and physiologic responses and
adaptations that occur during and following physical
activity and exercise
Exercise Physiology is concerned with ?
how the systems individually and
collectively respond to acute and chronic bouts of
physical activity and exercise
What led to the development of exercise physiology?
Funding for health-related research, and education programs by NIH
What are Acute Responses?
Changes in the systems of the body that occur in response to a
a single bout of physical activity or exercise.
Systems of the body control the body’s internal environment and
response to increased challenges to homeostasis
Acute responses in the cardiovascular system
Increases in heart rate, stroke volume, cardiac output, blood pressure, and a redirection of blood flow to the working tissues of the body.
Acute responses in the pulmonary system
Increases in air movement into and out of the lungs and increased blood flor through the lungs
Acute responses in the muscular system
Increases in force production, utilization, and production of energy and heat production
Acute responses in the endocrine system
Increases in the release of epinephrine and norepinephrine
What are chronic adaptations?
Changes in the systems of the body that occur in response to
repeated regular physical activity and exercise
Chronic adaptations in exercise work to ?
improve functions of the body while
at rest and during exercise
Chronic adaptations depend on
the type and amount of exercise
Chronic adaptations in the cardiovascular system
Increases in stroke volume and cardiac output and decreases in heart rate at the same absolute workload
Chronic adaptations in pulmonary system
Improved air movement into and out of the lungs and increased blood flow through the lungs at the same absolute workload
Chronic adaptations on muscular system
Increased energy production from fat and decreased lactic acid formation at the same absolute workload
Chronic adaptations in endocrine system
Decreased release of epinephrine and norepinephrine at the same absolute workload
Examples of acute adapatations
Muscle soreness and fatigue
Examples of chronic adapatations
Muscle development and increased endurance
What factors affect substrate metabolism?
▪Role of enzymes and hormones
▪ Interaction of fat and carbohydrate utilization
▪ Effects of intensity and duration
What are substrates?
energy source for the cells of the body
What is the crossover point?
when the body receives more of its energy from carbohydrate
rather than fat
What is hypoglycemia?
abnormally low blood glucose levels
Review crossover point image in
Powerpoint
What is insulin? Where is it secreted from?
Insulin is a hormone secreted from pancreatic B (beta) cells. It acts to control elevated plasma glucose. So if insulin is secreted high blood glucose will be regulated.
What is glucagon? Where is it secreted from?
Glucagon is a hormone secreted from pancreatic A (alpha) cells. It acts to control low plasma glucose. So if glucagon is secreted low blood glucose levels will be regulated.
The body closely regulates what?
Body closely regulates energy utilization during physical activity
and exercise
The movement of glucose from the blood into the cell depends on ?
the glucose transport protein
What is diabetes type 1?
an immune-mediated disease is characterized by β cell destruction
that usually leads to absolute insulin deficiency. Autoimmune destruction of B cells.
Paitents with Diabetes type 1 are?
rarely obese, but obesity is possible
What is the treatment of Diabetes type 1?
Requires injections of insulin administered subcutaneously, or an
insulin pump
What is Diabetes Type 2?
insulin resistance with relative insulin deficiency and can progress to an insulin secretory defect with insulin resistance. The body can create insulin but it can not be processed at a sufficient rate.
What is insulin resistance?
a decreased ability of insulin to stimulate glucose uptake
and storage and to suppress hepatic glucose production
Most patients with type II diabetes are
obese and or have central obesity
What is insulin shock?
acute hypoglycemia usually resulting from an excessive insulin and characterized
by sweating, trembling, dizziness , and, if left untreated, convulsions and coma.
GLUT4 is the transport protein that enables
glucose to enter the cell.
Muscle fibers have
distinct contractile and metabolic characteristics
At rest and during low exercise intensities (< 40% of maximal aerobic capacity),
type I or slow twitch fibers are recruited predominantly
As exercise intensity increases
more type II or fast twitch fibers are recruited
More lactate formation occurs in
type II fibers
Type II fibers have higher activities of
glycolytic enzymes than do type I fibers
Training results in fibers taking on ?
taking on characteristics that help meet
the requirements of the physical activity or exercise
What is Myoplasticity?
capacity skeletal muscle has for adaptive change
What is resistance exercise?
▪Increase in the cross sectional area of the muscle (hypertrophy)
▪ Hypertrophy leads to an increase in maximum force generating capacity
▪ Mitochondrial volume density and capillary density actually decrease with a
program of high resistance training
▪ Glycolytic enzymes
What is endurance exercise?
▪ Has minimal impact on the cross-sectional area of muscle
▪ Increased mitochondrial size and density
▪ Increased oxidative enzyme concentrations
▪ Increased myoglobin concentrations
▪ Increased capillarization in muscle bed
▪ Increased O2 difference between arterial and venous blood
What are Type 1 fibers?
Slow twitch (ST)
Slow (S)
Slow, oxidative (SO)
intermediate
Tonic (postural)
What are Type IIa fibers?
Fast Twitch (FT)
fast, fatigue resistant (FR)
Fast, oxidative glycolytic (FOG)
RED
Phasic
What are type IIb fibers?
Fast Twitch (FT)
fast, fatigable (FF)
Fast, glycolytic (FG)
White
Plastic
What substrate is used in High Intesity, Short Duration?
Carbs
▪ maximum carbohydrate utilization is found at about 85% or higher
of VO2 max
What substrate is used in Low intensity, Long duration ?
Fats
▪ maximum fat utilization is found at about 33-65% of VO2 max
What happens to fats during low intensity exercise?
The lower intensity allows for fats to be broken down since they are
a much larger molecule
How does bone metabolism influence physical activity and exercise?
▪ Higher intensity mechanical loading forces that are unique, variable, and dynamic
result in changes to skeletal system and increased bone mineral density
What is Osteporosis?
▪ Characterized by loss of bone mineral density
▪ Increased risk of bone fractures
What is the Female athlete triad?
Osteoporosis
Functional Hypothalamic Amenorrhea
Low Energy Availability with or without an Eating disorder
Energy Balance and weight maintenance is critical?
▪Critical for promoting overall good health and optimizing performance in certain sports and athletic competitions
▪ Body weight control can be described using the energy balance equation
What is energy balance?
Energy intake = Energy expenditure = Stable body weight
What is positive energy balance?
Energy intake > Energy expenditure = Increase in body weight
What is negative energy balance?
Energy intake < Energy expenditure = Decrease in body weight
What is the hormone Leptin?
▪ Found primarily in adipose tissue
▪ Suppresses appetite when caloric intake reaches ideal fat stores
▪ With a gene defective for leptin production or leptin sensitivity the
brain inadequately assess the body’s adipose tissue status
▪ Essentially the urge to eat is continued
What is Ghrelin?
▪ Increases hunger
▪ Decreases the breakdown of fat and increases gastric motility and acid production