Exercise Science Mod 1

Benefits of physical fitness

-improves mental and emotional state

-reduces stress, anxiety, and depression

muscular strength

how much weight a person can lift at one time

muscular endurance

contracting muscle against force for an extended period of time

cardiovascular endurance

ability to efficiently use the heart and the lungs to pump blood to all working muscles

flexibility

ability to move joints through normal range of motion

body composition

makeup of the body in terms of relative percentage of fat free mass and body fat

SAID Principle

specific adaptation to imposed demands

-body will adapt to specific type of stress placed on it

physiological benefits of SAID

-increased respiratory capacity

-maximal oxygen consumption

-lower blood pressure

-improved blood glucose and blood lipid control

psychological benefits SAID

reduction of anxiety and depression

improved mood and emotional wellbeing

demands of exercise will

increase heart volume and heart size

Aerobic Endurance Training: Increased

plasma volume, enlarged left ventricle, diastolic volume, stretching of cardiac fibers

increase in mitochondria: more ATP

increase in mitochondrial oxidative enzymes: glycogen is spared, work harder for longer

Aerobic Endurance Training: Decreased

resting heart rate and exercising heart rate at a given intensity

reduction of arterial blood pressure at submaximal load

lower blood pressure in hypertensive individuals

Neuromuscular Adaptations

-more significant from resistance training than aerobic endurance training

-strength gains as a result

All or none principle

principle of muscle contraction that states that when a motor unit is activated, all of the muscle fibers will maximally contract

Agonist

muscle directly responsible for observed movement; also called prime mover

Antagonist

muscle that acts in opposition to the contraction produced by agonist

the cardiovascular system consists of

heart, blood vessels, blood

blood

-plasma, red and white blood cells

-arteries carry blood away from the heart to deliver oxygen to the body

-veins carry deoxygenated blood to the heart

-capillaries act as a place for gas exchange

right side of heart

right atrium and right ventricle push deoxygenated blood into lungs to pick up oxygen

release CO2 in exchange for oxygen

left side of heart

left atrium and left ventricle receive newly oxygenated blood to send to rest of body’s tissues

flow of blood through heart

Right atrium > right ventricle > pulmonary artery > lungs > pulmonary veins > left atrium > left ventricle > aorta > rest of body

during exercise, what happens to breath?

rate and depth of each breath increases: TV

allows more oxygen to be released in the lungs

Cardiac Output Equation

CO = HR x SV

Cardiac output numbers

rest CO = 1.3 gal per min

maximal exercise CO = 8-10 gal per min

heart rate increases in linear fashion

SV increases up to 40-50% of maximal capacity and levels off

slow twitch muscles are

oxidative

mitochondria increase in size and numbers

levels of oxidative enzymes used to produce ATP also increase

If body can aerobically produce more ATP, you’ll be able to perform more efficiently for a longer period of time

what happens in hot conditions?

-body uses vasodilation and sweating to reduce heat

-reduction of body heat is difficult in extremely warm temps

vasodilation

reduces venous return and lowers SV

heart rate elevates to maintain CO

blood volume decreases and dehydration occurs when lost fluids are not replaced

Humidity does what

increases exercise stress because it prevents sweat from evaporating

heat exhaustion

result of inadequate circulatory adjustments and fluid loss

heat stroke

represents a complete failure of the heat regulating mechanisms

core temp exceeding 104 degrees F or 40 degrees C

heat exhaustion symptoms

-weak, rapid pulse

-low blood pressure

-headache

-nausea

-dizziness

-general weakness

-paleness

-cold, clammy skin

-profuse sweating

-elevated core temp

heat exhaustion treatment

-stop exercising

-more to a cool, ventilated area

-lay down and elevate feet 12-18 inches

-give fluids

-monitor temp

heat stroke symptoms

-hot, dry skin

-bright red skin color

-rapid, strong pulse

-labored breathing

-elevated body core temp above 104 degrees F

heat stroke treatment

-stop exercising

-remove as much clothing as feasible

-try to cool the body immediately in any way possible

-give fluids

-transport to emergency room immediately

programs in the heat

gradual start

low intensity

last an hour

performed every day 9-14 days

body’s heat tolerance

expansion of plasma volume

decreased heart rate and core temp

increased sweat rate

exercise in the cold

loss of body heat can lead to hypothermia

cold temps can cause vasoconstriction leading to increase in blood pressure

layer clothes and cover head

begin run by going into wind to have a tailwind on return

replace loss of fluids

exercise in altitude

less pressure which drives oxygen into blood

reduce intensity to keep heart rate in acceptable target zone

approx 2 weeks to acclimatize

warm up/cool down should be extended

exercise in pollutants

high levels = irritation of airways = decrease of O2 carrying capacity of the blood

workout in morning and reduce intensity; look at indexes before heading outside

improved cardiac efficiency

heart pumps more blood with each beat

increased respiratory capacity

body can take in more oxygen

increased maximal oxygen uptake

body can use more oxygen