Benefit to physical Activity and Acute Response to Aerobic Activity Flashcards
Study of Exercise science
Provides understanding of how the body responds to acute and chronic demands placed on it by increased energy demand placed on it from exercise.
Physical activity
any bodily movement comes about from contraction of skeletal muscle and increase energy expenditure. (exercise and everyday activities)
Exercise
Structured form of physical activity that has specific purpose.
4 components of physical fitness
- muscular fitness through muscular strength and endurance. muscular strength
- Cardiovascular or cardiorespiratory endurance (aerobic) maximal capacity of heart, blood vessels, and lungs to deliver oxygen and nutrients to working muscles so energy can be produced.
- Flexibility ability to move joints through their normal range of motion. prevent injuries.
- Body Composition- makeup of body in relation to proportion of lean body mass and body fat.
lean body mass
muscles, bones, nervous tissue, skin, blood organs. high metabolic rate and are positive influence to physical performance.
essential fat
How much for men and women?
amount of fat necessary for maintenance of life and reproduction. men 2-5% body fat and women 10-13% body fat.
At rest body is under control of which nervous system?
Parasympathetic
With onset of exercise what happens to nervous systems?
Parasympathetic system is inhibited. Sympathetic takes over. stimulated cardiovascular system and adrenal glands release catecholamines: Epinephrine and norepinephrine.
oxygen consumption during aerobic exercise (table)
when start exercise is immediate oxygen deficit (2-4 minutes), until meet steady state. then when cessation of exercise have Excess Post Exercise Oxygen Consumption (EPOC)
if exercise intensity too high and you cannot reach steady state?
have to supplement ATP production via anaerobic metabolism. lactate accumulates and exercise can only be done for a couple of minutes. Start to get buildup of CO2 so you hyperventilate to blow off CO2.
First ventilatory threshold
first time lactate begins to accumulate in the blood and is caused by need to blow off excess CO2.
Second ventilatory threshold
lactate is rapidly increasing with intensity. usually is point where blowing off Co2 not adequate to buffer increase in acidity.
What percent are athletes in Vt1 and VT2?
VT1- 70-80%, between VT1 and VT2- Less 10%, above VT2- 10-20%
Responses to BP during exercise (systolic and diastolic)
Systolic BP- increases in linear fashion throughout exercise.
Diastolic- stays the same or decreases slightly during exercise.
During Exercise total energy expenditure increase by how many times?
15 to 25 times
Cardiac output is product of which 2 things
Heart rate and Stroke volume
Sinoatrial Node (SA Node)
Posterior wall of the right atrium. Serves as the Pacemaker for the heart. spontaneously depolarize and repolarize to provide innate stimulus for heart contractions.
Atrioventricular Node (AV Node)
located on floor of right atrium. facilitate ventricular contraction. Atria contract first, then the ventricles
Vagus nerve
Parasympathetic fibers, that reach Sa and AV nodes, release acetlycholine to decrease activity os SA and AV nodes to reduce heart rate. At rest heart is under influence of Vagus nerves (Parasympathetic Tone). Decrease in parasympathetic tone increases heart rate, and an increase in parasypmathetic tone decrases HR.
Frank Starling Mechanism
The Stroke Volume of heart increases in response to an increase in volume of blood in ventricles before contraction.
Vasoconstriction in exercise
sympathetic stimulation causes decrease in blood for non exercising muscles except heart.
Vasodilation
prepares the muscle for action by allowing more blood into exercising tissues.
blood flow distribution at rest and during exercise for organs
Muscles- Rest: 15-20% and Max Energy: 84% Liver- Rest: 27% and Max energy: 2% Heart- Rest: 4% and Max Energy: 4% Skin- Rest: 6% and Max Energy: 2% Brain- Rest: 14% and Max Energy: 4% Kidneys- Rest: 22% and Max Energy: 1%
Summary:
Blood Flow increases to muscles
Stays same in Heart
Decreases in all other organs
Transient Hypertrphy
When fluid accumulates during resistance training. Appear Pumped up from exercise. Does down after a few hours.
Minute Ventilation
volume of air breathed per minute. During higher intensity exercise after VT2 minute ventilation increases disproportionally to increase oxygen consumption.
Tidal volume
volume of air inhaled and exhaled per breath.
Catecholamines
Epinephrine and Norepinephrine, are hormones of sympathetic nervous system. Located in adrenal gland atop each kidney.
Epinephrine responses (slight norepinephrine response)
increases cardiac contraction
vasoconstriction in non exercising muscles
vasodilation of heart
Epinephrine only dilates respiratory passage to aid in moving air
Influences blood glucose levels (stimulates carbs and fat to make them available as energy for muscles)
epinephrine stimulates CNS
Insulin
hormone released by pancreas. Directly involved in uptake of glucose into tissue. Exerts a hypoglycemic effect by reducing blood glucose levels and promotes uptake of glucose, fats, and amino acids for storage.
the sympathetic system suppresses insulin release from pancreas.
Glucagon
Released by the pancreas. has opposite effect as insulin on blood glucose levels. Glucagon stimulates release of glucose from the liver. Facilitate increase in blood glucose concentration.
Fast Acting hormones
Catecholamines, Insulin, and Glucagon
Cortisol
Released from adrenal cortex stimulates Free fatty acid mobilization and mobilized glucose symthesis in liver.
Slow acting, increases with exercise intensity and stresses on body. High cortisol levels occur after long duration events. High levels of Cortisol can cause protein breakdown and ketosis.