Exercise phys updated

Fitness
• A. Being active improves health: 30 minutes of
accumulated physical activity on most days
of the week
• B. Being “fit” goes beyond health and requires a
comprehensive exercise program that
includes the following components
• 1) Cardiorespiratory endurance
• 2) Muscular strength and endurance
• 3) Flexibility
• 4) Body composition
• 5) Balance

Components of Fitness
• 1) Cardiorespiratory endurance
– The ability to perform large muscle movements over a
sustained period
• 2a) Muscular strength
– The max force that a muscle can produce against a
resistance in a single maximal effort.
• 2b) Endurance
– The capacity of a muscle to exert force repeatedly
against a resistance

Components of Fitness
• 3) Flexibility
– The range of motion around a joint
• 4) Body composition
– The make-up of the body in terms of the relative
percentage of fat free mass and body fat
• 5) Balance
– The ability to maintain the body’s position over it’s
base of support.

The 5 Fitness Components

 Supply the body With O2  Involves the heart. Lungs, &
and remove wastes blood vessels

 Ability of a muscle or group
of muscles to exert maximal
 Ratio of lean body mass (muscles, force against a resistance
tendons, organs, bone, etc.) to  1 rep max (how much weight
fat mass you can lift on one repetition)
 What is your % body fat

 Ability of a muscle, or group of
 Ability of a joint and surrounding
muscles to move freely through muscles to exert force over a period
of time against a resistance that is less
its Range of Motion (ROM)
 How far can your muscle move than max
 How many times can you lift 80% of your max
during stretches

Physiology of the Cardiorespiratory System
• For muscles to contract, they need energy in the form of
ATP. The cardiorespiratory system is responsible for the
three basic processes to produce this energy:
– Get oxygen into the blood (oxygen-carrying capacity)
– Deliver oxygen to the muscles (oxygen delivery)
– Extract the oxygen from the blood to form ATP
(oxygen extraction)
• Oxygen-carrying capacity is affected by two primary
functions: (1) the ability to adequately ventilate the
alveoli in the lungs and (2) hemoglobin concentration in
the blood.

Basic Processes Blood Delivery
and Nutrient Exchange
• 1) Pulmonary Ventilation
– The total volume of gas inspired and expired
per minute
• 2) Cardiac Output
– The amount of blood pumped by the heart per
minute
– HR x SV
• 3) Oxygen Extraction
– The amount of O2 taken from the HB Molecule
and used in the exercising muscle.

Oxygen Delivery
• Oxygen delivery is a function of cardiac output (the
quantity of blood pumped per minute).
– Cardiac output (Q) = Stroke volume (SV) x Heart rate
(HR) (in beats per min)
• Stroke volume is the amount of blood pumped
during each heartbeat.
– Cardiac output increases due to increases in both SV
and HR.
• HR typically increases in a linear fashion up to
maximal levels.
• SV increases to about 40–50% of maximal
capacity, and then plateaus.

Oxygen Extraction
• Oxygen extraction from the blood at the cellular level
depends on muscle fiber type and the availability of
specialized oxidative enzymes.
– Slow-twitch muscle fibers are specifically adapted for
oxygen extraction and utilization.
– Aerobic production of ATP occurs in the mitochondria
of the cells.
– The circulatory system increases blood flow to the
active muscles and decreases blood flow to non-
active areas such as the viscera, allowing a higher
concentration of O2 to be extracted.

Oxygen Consumption
• The more oxygen a person can take in, deliver, and
utilize, the more work he or she can perform.
• VO2max refers to one’s maximal oxygen consumption.
– It is expressed in either “relative” terms (mL/kg/min)
or “absolute” terms (L/min).
– Relative VO2max allows comparisons between
individuals. Absolute VO2max is used to determine
caloric expenditure during specific activities.
• Approximately 5 kcal of energy are burned for
every liter of oxygen consumed.

Energy production
• 1) Adenosine triphosphate (ATP)
• a.Manufactured by the mitochondria in the muscle
cell
• b. ATP is the energy source used to drive muscle
contraction
• c. Fatty acids and glucose are used to produce ATP
• d. Amino acids are not a preferred energy source,
but are used in an undernourished individual

Energy production
Energy System Substrate Limitation to Produce Primary Use
ATP
ANAEROBIC
Phosphogen Creatine Muscle stores very little CP High-intensity, short-
phosphate (CP) and ATP duration activities;
Stored ATP less than 10
seconds to fatigue
Anaerobic Glucose and Lactic acid build-up causes High-intensity, short-
glycolysis glycogen rapid fatigue duration activities;
from 1–3 minutes
to fatigue

AEROBIC
Fatty acids, Depletion of muscle Long-duration, sub-
glucose, and glycogen; insufficient O2 anaerobic threshold
glycogen delivery activities; longer
than 3 minutes to
fatigue

Anaerobic Threshold
• The anaerobic threshold (AT) is reached when exercise
intensity increases above steady-state aerobic
metabolism and anaerobic production of ATP occurs.
• When the AT is crossed, exercise can only be sustained
for a few minutes before hyperventilation begins to
occur.
– Lactate accumulates progressively in the blood and
the oxygen deficit and corresponding EPOC are
extremely high.
– At this point, the body attempts to rid excess CO 2 (a
by-product of acid metabolites). The increase in
respiration is called the second ventilatory threshold
(VT2).
– VT2 is an indirect indicator of AT.

Ventilatory Threshold
• There are two distinct changes in breathing patterns during incremental exercise: the
first ventilatory threshold (VT1) and the second ventilatory threshold (VT2).
• VT1 occurs as soon as blood lactate begins to accumulate and the body needs to rid
itself of excess CO2 through increased respiration.
– Can be identified using the “talk test.” It is the first point at which it becomes noticeably more
difficult to speak.
• VT2 occurs as blood lactate rapidly
increases with intensity, and represents
increased hyperventilation past the need
to rid the body of excess CO2.
– Also known as lactate threshold (LT) and
respiratory compensation threshold (RCT)
– Speaking is definitely not comfortable
at this intensity.

Fuel Use During Exercise: Carbohydrates
• Carbohydrates are the major food macronutrient for the metabolic
production of adenosine triphosphate (ATP) and the only one whose stored
energy can produce ATP anaerobically.
– Stored as glycogen in the muscle and liver
• Glycogenolysis (breakdown of liver glycogen to glucose) is the primary regulator of
blood glucose.
– Carbohydrates used during
exercise come from both
glycogen stores in muscle
tissue and blood glucose.
• The relative contribution
of muscle glycogen and
blood glucose used during
exercise is determined by
intensity and duration.
• After the first hour of
submaximal exercise,
carbohydrate metabolism
shifts from muscle
glycogen to glycogenolysis
in the liver.

Fuel Use During Exercise: Fats

• Fats are mainly stored as triglycerides in
adipocytes, which must be broken down
into FFAs and glycerol.
– During low-intensity exercise, circulating FFAs
from adipocytes are the primary energy
source from fat, but during higher intensities,
muscle triglyceride metabolism increases.
– As duration increases, the role of plasma
FFAs as a fuel source increases.

Fuel Use During Exercise: Protein
• Protein plays a small role in the fueling of exercise. It must be
broken down into amino acids, which can be supplied to the muscle
tissue from the blood and from the muscle fiber itself.
– Skeletal muscle can directly metabolize certain amino acids to produce
ATP.
– During exercise, glucose stored
in a non-exercising muscle
can be delivered indirectly
to the exercising muscle
via the glucose-alanine pathway.

Cardiorespiratory adaptations to
acute aerobic exercise
• 1) Increased heart rate (HR)
• 2) Increased stroke volume (SV)
• a.The amount of blood pumped from each ventricle
each time the heart beats
• b.Measured in mL per beat

• Cardiac output = HR x SV

• 3) Increased cardiac output
• a. Cardiac output = HR x SV
• b. A typical cardiac output at rest:
• 60 bpm x 70 mL/beat = 4200 mL/min
• (approximately 1 gallon of blood per min)
• 4) Increased breathing rate

• 5) Increased systolic blood pressure
• a. Due to the cardiovascular system attempting to
increase O2 delivery to the muscles
• b. However, blood pressure greater than
250/115 mmHg is an indication to terminate
exercise (hypertensive response)

• 6) No change (or a slight decrease) in diastolic
blood pressure
• a. Due to the dilation of vessels in the muscles and
the skin
• b. This decreases peripheral resistance (which is an
important benefit for individuals suffering from
heart disease, hypertension, diabetes, and
peripheral vascular disease)

Blood Pressure During Exercise
• Systolic blood pressure has a much higher increase during exercise than diastolic
blood pressure due to:
– Increased contractility of the heart
– Increased stroke volume
– The muscular need for greater force
and pressure to deliver blood to
the exercising muscles
– Vasodilation within the exercising
muscle, which results in more blood
draining from the arteries, through
the arterioles, and into muscle
capillaries, minimizing the change
in diastolic pressure

• 7) Blood is shunted from the viscera to the
working muscles
• a. Dilation of vessels that supply blood to the
exercising muscles
• b. Constriction of vessels that supply blood to
the abdominal area

• 8) Increased extraction of oxygen from the
blood into the working tissues
• a. A normal, healthy person is able to load the blood
with more O2 in the lungs than he or she is able to
use at the cellular level
• b. Therefore, the more efficiently an individual can
extract O2 from the hemoglobin in the capillaries,
the more fit he or she becomes

Chronic Training Adaptations to
Exercise
 SAID principle (specific adaptation to imposed demands)
 Examples include:
– Improved cardiac output efficiency (increased SV and lower HR)
(aerobic training)
– Increase in respiratory capacity (aerobic training)
– Increase in maximal oxygen consumption (aerobic training)
– Increase in bone density (weightbearing exercise)
– Improved control of blood glucose and lipids (physical activity)
– Maintained or improved lean body mass (weightbearing activity)
– Decreased depression and anxiety (physical activity)
– Higher quality of life (physical activity)

Cardiorespiratory adaptations due
to regular aerobic exercise
• 1) Decreased RHR
• a. With consistent exercise (as few as three months
of regular aerobic training), the interior
dimensions of the ventricles increase, allowing
them to hold more blood
• b. The same cardiac output can be maintained at a
lower HR due to the greater SV

• 2) Decreased relative working heart rate
• a. Since a given intensity requires a given amount of
O2, HR at any given intensity will be lower due to
increased SV
• b. A trained individual will have to work at higher
intensities to achieve the same HR he or she
achieved prior to being fit

• 3) Increased VO2max as SV
increases
• a. VO2max is the total capacity to consume
oxygen at the cellular level
• b. VO2max depends on two factors
• 1. The delivery of O2 to the working muscle by
the blood (cardiac output)
• 2. The ability to extract the O2 at the capillaries
and use it in the mitochondria

• 4) Increased O2 extraction
• a. Improved ability to remain “aerobic” at
higher intensities
• b. Increased capillary density
• c. Increased mitochondrial density
• d. Increased ability to create ATP

• 5) Increased fatty acid oxidation at any
submaximal intensity
• 6) More glycogen is stored in trained muscles
and less lactic acid is produced
• 7) Increased tolerance to lactic acid produced
during exercise

Exercising in the Heat
• In addition to exercising in a hot, humid environment, other factors
can cause heat overload.
– Poor hydration prior to exercise
– Overdressing
– Overweight and obesity
• During exercise, the internal heat load is brought to the skin’s
surface to be cooled via the secretion of water by the sweat glands
(evaporation).
– The goal (given favorable environmental conditions) is to prevent body
temperature from rising more than 2 to 3°F.
– When the ability to dissipate heat is compromised, injuries occur.

Physiological Responses to Exercising in the Heat
• Dissipating internal body heat is more difficult in the heat, resulting in a
higher heart rate than normal at any level of exercise to maintain cardiac
output.
• A hot humid environment is the most stressful environment for exercising
and poses the risk of heat exhaustion and heat stroke.

Safety in the Heat
• The heat index, as presented on the next slide, provides guidelines
on when exercise is safe and when it should be avoided.
• Tips to consider before exercising in the heat:
– Begin gradually
– Always wear lightweight, well-ventilated clothing
– Avoid impermeable or non-breathable garments
– Replace body fluids as they are lost
– Record daily body weight
– Air movement is critical for adequate cooling

Exercising in the Cold
• The excessive loss of body heat can lead to a generalized vasoconstriction
and conditions such as hypothermia, frostbite, and increased blood
pressure.
• Strong wind can accelerate heat loss.
– The windchill index, which is presented on the following next, provides guidelines
for determining if exercise is safe.
• Tips to consider before exercising in the cold:
– Wear several layers so that garments can be removed or replaced as needed
– Allow for adequate ventilation of sweat
– Wear garments made of materials that allow the body to give off body heat
during exercise and retain body heat during inactivity
– Replace body fluids in the cold, just as in the heat
– Monitor body weight over several days

Altitude
• 1) Since there is less partial pressure of O2 at
higher altitudes, HR and respiratory rate
increase
• 2) During exercise HR may increase up to 50%
higher than normal
• 3) Decrease exercise pace so the client can
complete the session without becoming
exhausted
• 4) It can take up to 2–5 weeks to acclimate to a
new altitude

Exercising at Higher Altitudes
• At moderate-to-high altitudes, the partial pressure of
oxygen in the air is reduced.
• Acclimatization (physiological adaptation to an unfamiliar
or unaccustomed environment) begins in a couple
weeks, but it may take several months to fully
acclimatize.
– Gradually increase exercise intensity over several
days
– Increase warm-up and cool-down periods
– Take frequent exercise breaks at a lower intensity

Altitude Sickness
• The higher the altitude, the greater the risk.
• Altitude sickness can be avoided by proper
acclimatization.
• Signs and symptoms of altitude sickness include:
– Shortness of breath
– Headache
– Lightheadedness
– Nausea

Exercising in Air Pollution

• Inhaled air pollutants (i.e., smog) negatively
affect the body and performance.
• The overall physiological effects depend on the
amount of pollutant in the air, the length of
exposure, and the amount of air breathed.
• Exercising early in the morning and avoiding
high-traffic areas can help minimize exposure.

Age
• Generally, exercise performance improves from puberty
until young adulthood, followed by a slow decline.
– If a person maintains activity levels, performance can
be preserved into the early 30s, but inevitably
declines beyond age 60.
– Individuals who are sedentary and over the age of 45
(for males) and 55 (for females) should avoid high-
intensity activity the first several weeks to decrease
the risk of triggering a heart attack.

Gender
• The relative amounts of testosterone (in males)
and estrogen (in females) account for specific
variances in males and females and their
physiological response to exercise.
• Outside of the hormone-attributed differences,
men and women have very similar responses to
exercise.

Pregnancy
• Outside of weight gain, change in body shape, and the
diversion of part of the cardiac output to the developing
baby, pregnancy has minimal effect on exercise
performance.
– Exercise performance will decrease as the pregnancy
progresses. However, exercise intensity and duration
should be reduced to maintenance levels during
pregnancy, as guided by comfort.
• Current research does not support the traditional
concerns about hyperthermia and circulatory
diversion.
• It is not recommended to engage in intense training or
competitions or to reduce body fat during pregnancy.

General Adaptation Syndrome
• General adaptation syndrome refers to the body’s predictable
response to stressful events (including heavy exercise).
• Three stages
– Shock or alarm phase (usually lasts 2 to 3 weeks)
• The individual initially exhibits signs of fatigue, weakness, and soreness.
• He or she soon experiences remarkable gains (attributed to neuromuscular
adaptations).
– Adaptation or resistance phase (begins around weeks 4 to 6)
• Major muscular adaptations (biochemical, mechanical, and structural)
• Progressive increases in muscle size and strength
– Exhaustion phase (may occur at any time)
• Symptoms similar to the first phase, but inadequate repair or recovery time
lead to burnout, overtraining, reduction or elimination of overload, injury,
illness, or lack of adherence

Overtraining
• Overtraining often occurs during periods of intense overload in which signs
and symptoms are individualized and include a combination of both
physiological and emotional factors.
• Some signs and symptoms include:
– A decline in physical performance with continued training
– Elevated heart rate and blood lactate levels at a fixed submaximal work rate
– Weight loss
– Sleep disturbance
– Multiple colds or sore throats
– Irritability, restlessness, excitability, and/or
anxiousness
– Loss of motivation and vigor
– Lack of mental concentration and focus
– Lack of appreciation for things that are normally enjoyable
• The best way to prevent overtraining is periodization.

Delayed Onset Muscle Soreness (DOMS)
• Research suggests DOMS is caused by tissue injury from excessive
mechanical force, particularly eccentric force, exerted on muscle
and connective tissue.
– Generally appears 24–48 hours after strenuous exercise
– Is thought to result from a series of events activated by strenuous exercise:
• First, structural damage occurs as a result of strenuous eccentric muscle
actions.
• As a result, calcium is leaked out of the sarcoplasmic reticulum and collects
in the mitochondria, halting ATP production.
• The build-up of calcium activates enzymes that break down proteins.
• The breakdown of proteins causes an inflammatory process.
• Lastly, the accumulation of histamines, potassium, prostaglandins and
edema stimulates pain receptors, leading to the sensation of DOMS.
– Attempt to reduce DOMS by starting at a low intensity and progressing slowly
through the first few weeks while minimizing eccentric actions.

General Training Principles
• Principle of specificity
– The exercise response to any training program is specific to the mode
and intensity of training.
• Principles of overload and progression
– Overload involves increasing the load on the tissue or system above
and beyond the normal load.
– Progression is the systematic process of applying overload.

General Training Principles (cont.)
• Principle of diminishing returns
– The rate of fitness improvement
diminishes over time as an individual’s
fitness approaches its ultimate genetic
potential.
• Principle of reversibility
– When training ceases, all gains will
return
to pre-training levels and may possibly
decrease to the point where they are
only supporting the demands of daily
use.

Exercise phys updated

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Exercise phys updated

Similar to Exercise phys updated (20)

More from ravostulp

More from ravostulp (15)

Exercise phys updated