TRAINING EFFECT
- An increase in functional capacity of muscles and other bodily tissues as a result of increased stress (overload) placed on them
- Trainer's ability to effectively draw your clients into a fitness lifestyle or maintain optimal health largely depends on your knowledge of the muscular, cardiopulmonary, and metabolic adaptations to exercise
HOMEOSTASIS
- The automatic tendency to maintain a relatively constant internal environment
- Must be maintained regardless of ever-changing external environment
- Feedback systems must exist so that various physiological functions turn on and off
MACRONUTRIENTS
- Carbohydrates, fats, and proteins
- Must be converted into biologically useable form of energy
- Uses:
- fuel physical activity
- provide structural components of body
CARBOHYDRATES (CHO)
- Sugars and starches used by the body as fuel
FATS
- Compounds that store energy
PROTEINS (PRO)
- Important components of cells and tissues
- Large, complex molecules made of Amino Acids (AA)
WALTER BRADFORD CANNON
- Credited with coining the term "homeostasis"
METABOLISM
- Reactions that occur throughout the body to turn food into biological energy
- Must be regulated in order to maintain homeostasis
- Continually occurring in the trillions of body cells
- Includes only the chemical changes that occur withing tissue cells (doesn't include those changes or breakdown in the GI tract)
METABOLIC FUNCTIONS UNDER HOMEOSTATIC CONTROL
- Thermoregulation
- Hormone production and concentration level maintenance
- Maintenance of serum oxygen and carbon dioxide levels
- pH balance in blood and cells
- Water content of cells and blood
- Blood glucose levels and other nutrient levels in cells
- Metabolic rate
GLUCOSE
- Principal circulating sugar in the blood and the major energy source of the body
KETONE BODIES
- Bodies produced as intermediate products of fat metabolism
LACTIC ACID
- Byproduct of glucose and glycogen metabolism in anaerobic muscle energetics
AMINO ACID (AA)
- Building blocks of protein
- 24 amino acids which form countless numbers of various proteins
FATTY ACID (FA)
- Any of a large group of monobasic acids
- especially found in animal and
vegetable fats and oils
2 PHASES OF METABOLISM
- Anabolism
- Catabolism
- both occur simultaneously and
constantly, but differ in magnitude
depending on level of activity or rest and
when the last meal was eaten
ANABOLISM
- Building up in the body of complex chemical compounds from simpler compounds (EX: Amino Acids to proteins)
- Includes the chemical reactions that combine different biomolecules to create larger, more complex ones
- Net result is the creation of new cellular material (EX: enzymes, protein, cell membranes, new cells, growth and repair of many tissues)
- Stored as glycogen or fat in muscle tissue
CATABOLISM
- Breaking down in the body of complex chemical compounds into simpler ones (EX: proteins to Amino Acids)
- Chemical reactions that break down complex biomolecules into simpler ones for energy production, recycling of molecular components, or for their excretion
- Provides the energy needed for transmitting nerve impulses and muscle contraction
METABOLIC SET POINT
- Base rate of metabolism that the body seeks to maintain
- Results in basal metabolic rate (BMR)
- Regulated by both genetic and environmental factors
- Can be changed through diet and physical activity
BASAL METABOLIC RATE (BMR)
- Minimum energy required to maintain the body's life function at rest
- Usually expressed in calories per hour per square meter of the body
THERMIC EFFECT
- The heat liberated from a particular food
- Measure of its energy content and its tendency to be burned as heat
- The process of heat liberation is also referred to thermogenesis
ABBREVIATIONS IN CALCULATING ENERGY EXPENDITURE
- ALF= Activity Level Factor
- DCE= Daily Calorie Expenditure
- HC= Height (cm)
- HI= Height (in)
- WKG= Weight in kg
- WP= Weight in lbs
ACTIVITY LEVEL FACTOR (ALF)
- Sedentary
ALF= 1.2
- Lightly Active
ALF= 1.375
- Moderately Active
ALF= 1.55
- Very Active
ALF= 1.725
- Extremely Active
ALF= 1.9
CALORIE
- Unit of heat
- Specifically, the amount of energy required to raise the temperature of 1 gram of water 1 degree Celcius at 1 atmosphere
- Unit is so small, therefore the unit kilocalorie is used (1 kilocalorie= 1,000 calories)
KILOCALORIE (KCAL)
- Unit of measurement that equals 1,000 calories
- Used in metabolic studies
- The amount of heat required to raise the temperature of 1 kg of water 1 degree Celcius at 1 atmosphere of pressure
- Used in nutrition to express the fuel (energy) value of food
- Synonymous with "Calorie" (with a capital C)
RESPIRATORY QUOTIENT (RQ)
- Method of determining "fuel mix" being used by the body
- Way to measure the relative amounts of fats, proteins, and carbohydrates being burned for energy
- Ratio of the volume of carbon dioxide expired vs. the volume of oxygen consumed
- amounts of oxygen used up for the
combination of fat, carbohydrate, and
protein differ
- Differences in the RQ indicate which
nutrient source is being the primary
energy source
OXIDATION
- Chemical act of combining with oxygen or of removing hydrogen
MAXIMAL OXYGEN UPTAKE (VO2 max)
- Highest rate of oxygen consumption a person is capable of
- Shows what your body is burning for fuel
BRANCHED-CHAIN AMINO ACIDS (BCAA)
- Amino Acids L-leucine, L-isoleucine, and L-valine
- All have a particular molecular structure that gives them their name
- Comprise 35% of muscle tissue
- BCAAs, particularly L-leucine, help increase work capacity by stimulating production of insulin, the hormone that opens muscle cells to glucose
- BCAAs are burned as fuel during highly intense training and at the end of endurance events when the body recruits protein for as much as 20% of energy needs
EXERCISE & METABOLIC RESPONSE
- High-intensity exercise stimulate development of fast-twitch muscle fibers
- Low-intensity exercise develops slow-twitch muscle fibers
- Hormonal changes also occur
- benefited and facilitated with a nutrient
profile matching the type of metabolic
fluctuation
CHANGES CAUSED BY ENDURANCE EXERCISE
- Increased muscle glycogen storage capacity
- Increased muscle mitochondrial density
- Increased resting ATP content in muscles
- Increased resting CP content in muscles
- Increased resting creatine in muscles
- Increased aerobic enzymes
- Increased % of slow-twitch muscle fibers
- Decreased % of fast-twitch muscle fibers
- Decreased muscle size (compared to strength training)
- Increased cardiac output
- Decreased resting heart rate
- Decreased body fat
- Increased Krebs Cycle enzymes
- Increased number of capillaries
MAJOR CHANGES FROM ANAEROBIC EXERCISE
- Increased size and number of fast-twitch muscle fibers
- Increased tolerance to higher levels of blood lactate
- Increased in enzymes involved in the anaerobic phase of glucose breakdown (glycolysis)
- Increased muscle resting levels of ATP, CP, creatine, and glycogen content
- Increased levels of growth hormone and testosterone after short bouts (45-75 min) of high-intensity weight training
MAJOR CHANGES FROM AEROBIC EXERCISE
- Increased mitochondrial density in slow-twitch muscle fiber
- results in increased energy production
from fatty acids
- maximum oxidative capacity develops
in all fiber types
- Increased aerobic capacity
- Increase in trained muscle capacity to utilize and mobilize fat (result of increased amounts of fat-metabolizing enzymes and increased blood flow)
- Increased myogobin content (an iron-protein compound in muscles that acts to store and transport oxygen in the muscles)
- Greater development of slow-twitch muscle fibers
ENERGY METABOLISM
- Series of chemical reactions that result in the breakdown of carbohydrates, proteins, and fats by which energy is produced, used, and given off as heat
4 TYPES OF PHYSICAL ACTIVITY
1. Strength/Power
2. Sustained Power
3. Anaerobic Power/Endurance
4. Aerobic Endurance
PHYSICAL ACTIVITY
- Contingent upon and limited by the ability of the body to transform food into biological energy
- Further contingent upon thousands of chemical reactions that occur throughout the body constantly
STRENGTH/POWER
- Energy coming from immediate ATP stores (EX: shot put, powerlift, etc.)
- Activities last about 0-3 seconds of maximal effort
SUSTAINED POWER
-Energy comes from immediate ATP and CP stores (EX: sprints, fast breaks, etc.)
- Activities last about 0-10 seconds of near-maximal effort
ANAEROBIC POWER/ENDURANCE
- Energy coming from ATP, CP, and lactic acid (EX: 200-400 m dash, 100 yd swim)
- Activities last about 1-2 minutes
AEROBIC ENDURANCE
- Energy coming from the oxidative pathway
- Activities that last longer than 2 minutes
ANAEROBIC PATHWAYS
- ATP/CP
- Glycolytic Pathway
ADENOSINE TRIPHOSPHATE (ATP)
- Organic compound found in muscle which, upon being broken down enzymatically, yields energy for muscle contraction
- The energy source for all human movement
CREATINE PHOSPHATE (CP)
- High-energy phosphate molecule that is stored in cells and can be used immediately to resynthesize ATP
3 WAYS MUSCLE CELLS MAKE ATP
- ATP/CP Pathway
- Glycolytic Pathway
- Oxidative Pathway
ATP/CP PATHWAY
- ATP and CP provide anaerobic sources of phosphate bond energy
- Energy liberated from hydrolysis (splitting) of CP re-bonds ADP and Phosphate to form ATP
ADENOSINE DIPHOSPHATE (ADP)
- Organic compound in metabolism
- Functions in the transfer of energy during the catabolism of glucose
- Formed by the removal of a phosphate molecule from ATP
- Compound of: adenine, ribose, and 2 phosphate groups
TYPE II MUSCLE FIBERS (FAST TWITCH)
- Muscle fiber type that contracts quickly
- Used mostly in intensive, short duration exercises
- More ATP can be stored, due to size and growth potential
- Also referred to as fast glycolytic muscle fibers
TYPE I MUSCLE FIBERS (SLOW TWITCH)
- Muscle fiber characterized by its slow speed of contraction and increased capacity for aerobic glycolysis
GLYCOLYTIC PATHWAY
- Metabolic process in which glucose is broken down to produce energy
- Anaerobic
- Uses either glycogen from muscle stores, or glucose from the blood
- Ends under maximal conditions at about 80 seconds before the oxidative pathway (and lower levels of activity) take over
GLUCONEOGENESIS
- Chemical process that converts lactate and pyruvate back into glucose
- When glycogen (stored in muscles) stores are depleted, glucose for emergency energy is synthesized from protein and the glycerol portion of fat molecules
- One important reason that ATP/CP athletes and glycolytic athletes are warned against aerobic exercise (muscle wasting)
ANAEROBIC THRESHOLD
- The point where increasing energy demands of exercise can't be met by the use of oxygen
- An oxygen debt begins to be incurred
- How far the body can go before it becomes vital to clear the lactic acid in order for work to continue
- can be pushed back by training
OXIDATIVE PATHWAY
- Metabolic process in which oxygen combines with lactic acid, resynthesizing glycogen
- Produce energy aerobically
KREBS CYCLE
- Citric Acid Cycle
- Set of 8 reactions, arranged in a cycle, in which free energy is recovered in the form of ATP
ELECTRON TRANSPORT CHAIN (ETC)
- Passing of electrons over a membrane
- Aids in a reaction to recover free energy for the synthesis of ATP
PYRUVATE
- Byproduct of glycolysis
BETA OXIDATION
- Series of reactions in which fatty acids are broken down
RESTING METABOLIC RATE (RMR)
- The amount of energy (kcal) required to efficiently perform vital bodily functions such as respiration, organ function, and heart rate while the body is awake, but at rest
- Handheld indirect calorimeters are used that measure VO2 (oxygen consumption