Transcript Physiology for Coaches

Physiology for Coaches
L2CCS&C
Skeleton
Skeletal Functions
• Support
• Protection
• Articulation through muscle attachment
• Be aware of differences between adults
and children
Major Muscles
Muscle Action
• Muscle origin; where muscle attaches to bone via
connective tissue (tendon) nearest centre of body
• Muscle insertion; where muscle attaches to bone via
connective tissue (tendon) away from centre of body
• Agonist; prime mover of the movement action
• Antagonist; opposite of agonist, can slow down or stop
the movement
• Synergist; assists n the movement or supports the body
during the movement
• Give examples
Muscle Action
Circulatory system
Composition of the blood
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Plasma
Red blood cells
White blood cells
Platelets
Functions of the blood
• Transport of oxygen
• Transport of energy in form of dissolved
food molecules
• Transport of hormones
• Removal of carbon dioxide
• Removal of other waste products
Structure of cardiovascular system
• Heart
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Right atrium
Right ventricle
Left atrium
Left ventricle
Arteries
Veins
Capillaries
Pathway RA>RV>Lungs>LA>LV>body>RA
Structure of the heart
The heart is a dual pump, circulating blood
through two separate closed systems. Oxygencarrying blood leaves the left ventricle through
the aorta. It circulates through the body and
returns, deoxygenated, to the right auricle via
the superior and inferior vena cava. The right
ventricle pumps this blood through the
pulmonary artery to the lungs, where it
exchanges carbon dioxide for oxygen.
Oxygenated blood then returns to the left auricle
of the heart, ready for arterial circulation,
through the pulmonary veins.
• Heart rate x stroke volume =cardiac output
Blood pressure
• Systolic: pressure against the arterial walls
during ventricular contraction ( x HR =
heart work)
• Diastolic: During ventricular relaxation is
the ease with which blood flows from the
arterioles into the capillaries
Mechanism of breathing
The diaphragm contracts and
moves downward, the pectoralis
minor and intercostal muscles pull
the rib cage outward. The chest
cavity expands, and air rushes into
the lungs through the trachea to fill
the resulting vacuum. When the
diaphragm relaxes to its normal,
upwardly curving position, the lungs
contract, and air is forced out.
Acute responses to exercise
• Aerobic
– Increase in systolic pressure
– Reduction in peripheral resistance
• Strength training
-Increase in systolic pressure
-Short term increase in diastolic pressure
Cardiovascular adaptations to
training (primarily aerobic)
• Increased ventricular volume
• Increased stroke volume
• Decreased resting and sub maximal heart
rates
• Increased muscle capilliarisation
• Increased plasma volume
• Reduction in resting blood pressure
More adaptations to training
• Increased maximal exercise ventilation
• Increased maximal oxygen consumption (VO2
Max)
• Increased tidal volume ?
• Increased oxygen extraction
• Onset of OBLA shifted
• Increased vital capacity
• Decreased resting breathing rate
• Increased maximal breathing rate
Biochemical adaptations to
aerobic training
• Increased myoglobin content (an intra
cellular oxygen transporting protein)
• Increase in number and size of
mitochondria
• Increase in activity of enzymes involved in
Krebs’ Cycle and electron transport chain
• Increase in muscular glycogen stores
• Increased ability to oxidise fat
Biochemical daptations to
anaerobic training
• Increased capacity of ATP-PC and
glycolytic systems
• Increased muscular stores of ATP and
activities of enzymes related to glycolysis
and ATP/PC systems
Age and Gender Differences
Gender differences:
• on average age for age
women have aerobic power
values that range from 73% to
85% of the values of men
• Women have lower Hb values,
smaller hearts and blood
volumes
Physiological changes as children
mature:
• Strength
• Power
• Endurance
Reduction with aging of:
• Maximal oxygen uptake
• Maximum heart rate
• Strength performance
• Peak power
• Lean muscle tissue, especially
fast twitch
• RPE changes
Energy sources:
• Fats (primary role)
• Carbohydrates (primary role)
• Proteins (secondary role)
• Carbohydrates are broken
down into simple sugars such
as glucose
• Fats are broken down into free
fatty acids and acetyl co
enzyme A which can enter
Krebs Cycle
• Proteins can be broken down
into amino acids which can be
converted to glucose
(gluconeogenesis), pyuvate
and various Krebs cycle
intermediates.
Energy Systems
• Energy is required to do physical work.
Energy for the muscles to work is provided
by a substance called ATP (adenosine
triphosphate).
• Bioenergetics is the flow of energy within a
biological system
Three energy systems provide ATP:
• Phoshagen system
• Glycolytic system
• Oxidative system
Phoshagen system:
• Provides energy at the start of
exercise, in sporting terms is
primarily used in short high
intensity activities such as
weight lifting and sprinting. In
this system two reactions
occur
– ATP > ADP + P +
energy
– ADP + creatine
phosphate > ATP +
creatine
Oxidative system:
• With sufficient oxygen present in the muscles (i.e. when
they are working at a lower intensity) the pyruvate from
glycolysis enters Krebs cycle.
• See diagrams
• Substances produced during Krebs cycle enter the
electron transport chain where further ATP is produced
• See diagrams
• Total yield of ATP from Oxidative (aerobic) system is 36
molecules per molecule of glucose.
• Energy is measured in Kilojoules. (USA still use
kilocalories)
Cellular Respiration: Simple overview
Glycolysis: Net Energy Gain 2ATP
Citric Acid/TCA/Kreb’s Cycle:
NADH & FADH from glycolysis & Kreb’s
Cycle enter Electron Transport Chain
Electron Transport Chain
Glycolytic system:
• Breakdown of glucose to produce 2
molecules of ATP
• With insufficient oxygen present pyruvate
is converted to lactate in so called “fast
glycolysis”. This produces ATP at a fast
rate but only for a short period of time as
the lactic acid built up causes muscle
fatigue
Lactate formation during “fast
glycolysis”
Nutritional Awareness
• Food groups; meat; vegetables; fruit; dairy; breads and cereals;
fats and oils
• Nutrients: carbohydrates; fat; protein; vitamins; minerals; water
• Healthy eating: sources of nutrients from food groups; energy and
nutrients; government and advisory body guidelines; eating patterns
and habits
• Nutrition and exercise: fuels for exercise – carbohydrates, fats;
fluids; sports drinks; dehydration; re-hydration
• Food labels: nutritional information; calculating nutrients
• Ergogenic aids and performance: research in ergogenic aids,
categories of ergogenic aids – pharmacological agents, hormonal
agents, physiological agents
• The reasons for supplement use by players/athletes
Food Pyramid
Physiological differences between
adults and children
• The biochemical pathways of anaerobic
respiration are not fully developed in
children
• The circulatory system is not fully
developed in children
• Sensitive periods in growth regarding
aerobic development
• Girls enter the sensitive phase before boys