Ex Phys Exam 3

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Specificity Principle

"you get what you train for" *The adaptive effects of training are highly specific to the training method employed; incorporate exercise that mimics desired function and objective Specificity applied to: • a. muscle groups the skill involves • b. exercises that stimulate the motor pathways the skill involves

Training Zone

% of 1 RM for mm endurance (force over a period of time) o 30-50% % of 1RM strength o 30-40% sedentary, untrained o 60-70% healthy novice to intermediate o 80-95 highly trained

Gradation of Force: Motor Unit Recruitment

(Multiple Motor Unit Summation) varying the number of motor units recruited at a given time low force needed few motor units recruited high force needed more motor units recruited example of activity that utilizes this??? o Strength, lifting • You know the weight and how much force you will need to produce o Soccer • Kicking to a friend vs kicking across the field

Gradation of Force: Frequency or rate of motor unit discharge

(Wave Summation) • Varying the *frequency* of contraction of the individual motor units. Repetitive stimuli to the muscle *before it totally* relaxes will increases the total tension produced.

Sympathetic Overtraining

(less common) • characterized by ↑ sympathetic activity during rest Symptoms: o Hyperexcitability o Restlessness o Impaired exercise performance

Parasympathetic Overtraining

(more common) • characterized by predominance of vagal activity during rest and physical activity Symptoms: o Fatigue during workout and recovery o ↓ performance o Altered sleep o Alter appetite; wt. loss o General malaise

Occlusion

***The greater the maximum voluntary contraction the less time one can hold a percentage of the maximum before occlusion will occur. Usually occlusion occurs by 60-70 % of max contraction At 45 % of maximal contraction men's occlusion rate has started but not women's At 65% of Max contraction men now have total occlusion but women have just started to have blood flow restrictions

Isokinetic Disadvantages

- equipment is large and expensive - set up time of patient - can't use in home exercise program

Isotonic Disadvantages

- heaviest weight lifted is the weight at the weakest angle of pull - at certain joint angles the muscle will not be exerting tension near its max force -max tension can't be distributed completely throughout the ROM - can't use when immobilized

Isokinetic Advantages

-ability to exert maximal force throughout ROM leads to optimal strength gain - allows for speeds of contraction closer to speeds seen in sports - can be concentric or eccentric - less apt to cause soreness - Safer - good in rehab - builds strength through ROM

Isotonic Advantages

-provides feed back -aids dynamic coordination -can resemble sport skill

Free Weights

-requires more balance and coordination (need spotters); multi- segmented -better simulates sports activities: provides movement versatility and greater stability -more multiple joint and variations; more than one plane -better power lifts -produce greater strength gains during short term training

Machines

-safer and easier to use; better for beginners and rehab (less chance of injury) -isolate specific mm group -body is stabilized -single joint, fixed plane -expensive

Recommendations for Initiating a Weight Training Program

1) Avoid max lifts: due to fatigue and injury 2) Light weights and multiple repetitions - don't use momentum - maintain proper body mechanics - technique is very important 3) Add weight slowly - only when target number of weight is achieved - endurance first than strength 4) Proceed from large to small muscle groups 5) Variety 6) Should not cause pain

Guidelines for exercise order:

1) more difficult first when fresh 2) multiple before single because single mm groups are critical for success in multiple-joint activities 3) gross motor activity serve as warm up for single joint 4) max power may not be derived if muscles are pre fatigued by single-joint exercises Ex. Snatches or power cleans before squats before leg curls

4 components involved in voluntary muscle contraction

1. CNS: ability to initiate nervous impulses 2. Peripheral nervous system: (Motor Nerve) innervating mm fibers ability to transmit impulses 3. Neuromuscular junction: to relay the nervous impulse from the motor nerve to the mm fibers 4. Muscle fiber function: ability of the contractile mechanism to generate force Any interruption will cause fatigue or not cause a contraction do to lack of force

3 factors produce neuronal facilitation

1. Decrease sensitivity of the motor neuron to INHIBITORY neurotransmitters (NT) 2. Reduced quantity of inhibitory NT transported to the motor neuron 3. Combination of the effect of both

Sliding Filament Theory: Steps in Contraction

1. Generation of action potential in the AMN; action potential travels down the axon to the presynaptic terminals 2. The presynaptic terminals release ACETYLCHOLINE into the synaptic cleft. 3. Acetylcholine binds with the post-synaptic receptors. This causes a change in the post-synaptic membrane permeability to sodium and potassium, which causes the cell to depolarize. 4. The end-plate potential spreads from the motor end-plate to the sarcolemma. The action potential travels the length of the muscle fiber then down the T-tubule. 5. The action potential travels from the T-tubules to the sarcoplasmic Reticulum (SR) in the muscle. SR releases calcium. 6. Calcium ions bind with troponin on the Actin filaments. -Troponin binds with Tropomyosin pulling Tropomyosin deeper into the groove exposing the sites on action. 7. Crossbridging occurs when Actin / Myosin are joined. 8. When Actin / Myosin are joined this activates myosin ATP-ase which in turns splits ATP into ADP and releases energy. 9. The energy released from ATP causes movement of the myosin cross-bridges and the filaments slide past each other and force is generated. 10. Uncoupling occurs when ATP binds to myosin bridge. This breaks the actin- myosin bonds allowing the cross-bride to disassociate from the action. 11. Cycle can repeat as long as calcium ion concentration is high enough to inhibit troponin-tropomyosin system. 12. When nerve stimulus to the muscle is removed calcium ions go back into the lateral sacs of the sarcoplasmic reticulum. (calcium is actively pumped back in) 13. Without calcium ion there is no binding to troponin. -Tropomyosin moves back into its original position closing the sites on the action. -This "turns off" the active sites on the action thus the mechanical link between action and myosin can't occur. -There is also a reduction in the activity of myosin-ATPase so there is no splitting of ATP 14. Muscle filaments return to their original state.

The 3 nerve fibers that serve the spindle

1. Primary Afferent is Annulospiral nerve fiber which responds to stretch of the spinal. 2. Flower-spray endings which are afferent (sensory) and are less sensitive to stretch. 3. Gamma efferent fibers or Fusimotor nerve • Gamma system or Gamma Loop o direct stimulation of Gamma neurons by the higher centers in the cerebral cortex; cause intrafusal to contract

Fatiguability & Fatigue

A third property distinguishing differences in motor units is their resistance to fatigue. FATIGUE: decline in muscle tension or force capacity with repeated stimulation or during a given time period

Tension Characteristics

ALL OR NONE if the stimulus is strong enough to trigger an action potential in the motoneuron, all the accompanying muscle fibers in the motor unit are stimulated to contract.

Muscle Endurance

Ability or capacity of a muscle group to perform repeated submax contractions against a load or to sustain a contraction for an extended period of time.

Case 1: Elderly individual who is deconditioned

Aerobic - easier Frequency o 3x a week o 1 day rest in between Duration o 10 minutes, maybe 2x a day Intensity o RPE of 10 or 11- start low Mode o walking - something he/she does daily o if he/she hates walking, then something they like to do Tell her what to wear (comfortable loose fitting clothes that are maybe light in color), hydration, safety, how you should and shouldn't feel

Anaerobic Glycolysis

Anaerobic Glycolysis Medium duration at a moderate - hard intensity 1:2 ratio 10-20 reps (30-120 seconds work/ 60-240s recovery) May lead to glycogen depletion so alternate hard and light days Goal: Overload the lactic acid system

Case 2: Collegiate Sprinter

Anaerobic training o what's the distance • 100m - short (ATP) * • longer (anaerobic) Mode o sprinting o work to rest interval (1:3) o min: 10 second run 30 second rest Intensity o all out o 16+ RPE o 85% Frequency o 3x a week o 15 reps

Resistance/Strength Training

Any form of active exercise in which a dynamic or static muscular contraction is resisted by an outside force. (manual or mechanical) Benefits: Increase lean mass Decrease fat mass Increase muscular strength and endurance

**Reaching Fatigue

As muscle function becomes impaired during prolonged submaximal exercise, additional motor units are recruited to maintain the required force output for the particular activity. In *ALL OUT exercise* all motor units maximally activated. Fatigue is accompanied by a decrease in *neural activity.*

Ratings of Perceived Exertion or RPE Borg Scale

Ask yourself how you feel during exercise-overall body exertion and fatigue 11,12 fairly light 50-69% of Max HR or 3-5 METS level for health recommendations RPE 13-15 corresponds with training zone

Aerobic Mode

Based on specificity principle • Walking • Jogging • X-country skiing • Jump rope • Circuit training • Elliptical • Rowing • Swimming • Water aerobic or water dance • Aerobic dance

Body Composition & Heat Transfer

Body Composition • Reduces body mass and fat mass Body Heat Transfer • Adaptations to heat tolerance: can exercise in hot environment because of >plasma volume and more responsive thermoregulatory system o (dissipate heat faster)

Aerobic Training: Major Goals

Central: Improved ability to deliver oxygen Local: Improved ability to extract oxygen Both lead to an increase in VO2 Max

Force Production of a muscle depends on:

Cross section Velocity Angle of Pennation

Uncharged ATP crossbridge-complex

Crossbridges of Myosin extend toward but do not interact with Actin ATP molecule is bound to the end of the crossbridge at rest

Delayed Onset Muscle Soreness (DOMS)

Decline in mm performance in healthy individual participating in high intensity, high volume strength and endurance training; unaccustomed exercise; associated with eccentric component • Too rapid progression • Inadequate rest • Inadequate diet and fluids Mm soreness aching beginning 12-24 hrs. after exercise; peaks 24-48 hrs.; can last up to 10-14 days (other sources 7 days)

Health related benefits of regular exercise

Decrease fatigue Improved performance: Improved blood lipids Enhanced immune function Improved body composition Enhanced sense well-being Decrease risk of certain diseases

Delorme vs Oxford 1 RM is 50 lb

Delorme • 25# for 10 reps • 37.5 # for 10 reps • 50# for 10 reps Oxford • 50 # for 10 reps • 37.5# for 10 reps • 25# for 10 reps

Muscle Fatigue with Anaerobic

Depletion of PCr Changes in myosin ATP-ase • Ion you need at muscular level to cause contraction Impaired glycolytic transfer because of reduced activity of key enzymes Disturbance of T-tubule system Ionic imbalances

*Delorme (Progressive Resistive Exercise)

Determine 10 RM Perform: • 10 reps @ 50% 10 RM • 10 reps @ 75% 10 RM • 10 reps @ 100% 10 RM • increase value of 10 RM weekly o (when 10 is easy move up)

Genetics of Muscle Fibers

Distribution and Magnitude of the fibers genetically determined and can't change. Adult muscle vary in the type of fibers. Majority of muscles are 50/50 Type I and Type II • Endurance Athletes > % Type I • Nonendurance > % Type II

How do you prevent overtraining?

Do not increase more than 10%/wk. • if low level fitness recommend progressing by only 5%/wk. Proper nutrition Proper rest between sessions

General Guidelines for Exercise

Establish target heart rate and max HR • not needed for strength training unless medically necessary Chose appropriate mode for pt Intensity should be safe and appropriate Proper clothing and footwear Proper surfaces/equipment Hydration Understanding of environmental conditions Person should have an understanding or normal and abnormal response to exercise Person should be instructed in how to monitor and determine intensity • RPE, %Max HR, Talk test, Educate person regarding overtraining: *do not increase more than 10%/wk.*

Tension Characteristics: Gradation of Force

Force of muscle action is varied from slight to maximal in 2 ways. • Frequency of motor unit recruitment • Number of motor units recruited *most of the time the two methods work together.* *variety of muscle tensions during movement and is also important for timing and coordination.*

Muscle Strength

Force or tension a muscle group can exert against a resistance in one maximal effort strength of an individual muscle depends on x-section area, fiber type composition, overall length of muscle

Aerobic Training Recommendations

Frequency: • 3-5 days/week • wt loss 5-7/wk • Diabetes daily Duration: • 30-60 minutes of continuous or intermittent • (10 min. bouts) o least you can do and still get a result (3x a day) *Intensity:* • 55/65% - 85%MHR • 40/50% - 80% Max VO2 • RPE of 11/12—13/15 Mode: • Large muscle groups

General Overtraining Symptoms

Frequent infections Altered immune and reproductive functions Mood disturbances (anger, anxiety, irritability, depression, apathy) Acute and chronic alteration in systemic inflammation Persistent feelings or mm soreness, overuse injuries and chronic joint pain Prolonged recovery for typical training session Elevated resting heart rate

Angle of Pennation

Fusiform o muscle fibers are parallel to the tendon Unipennate o one set of muscle fibers is at an oblique angle to the tendon Bipennate o mm fibers are aligned on either side at an oblique angle to the tendon Multipennate o contain >than 2 sets of fibers that converge at different angles and insert directly into tendons at both ends • The greater the angle of pennate the great the force production • If quad and deltoid were the same size, the deltoid would be stronger due to the angle of pennation

Warm Up Function

Gives cardio-respiratory system time to adjust Increase CO and blood flow to the skeletal muscles Increase muscle temp to elevate enzyme activity Increase muscle contraction by decreasing viscosity and increasing rate of nerve conduction Increases flexibility

Methods of Establishing Exercise Intensity

HR Talk Test or conversational exercise • 60-70% of Max HR (comfortable speech) Perceived Exertion Scale/RPE METS • multiples of resting metabolic rate assigned to activity Percent VO2 max • not practical in clinic Lactate Threshold • not practical in clinic

High, Moderate & Low Intensity (RM)

High intensity - 90% of given RM Moderate intensity - 70-90% of given RM Low intensity - below 70% of given RM

Reversibility/Detraining

If person terminates participation in regular exercise he/she will lose training adaptations; 1-2 weeks of detraining decreased both metabolic and exercise capacity with many training improvements fully lost within several weeks • Aerobic/anaerobic lost very quickly: depends of how "fit" • Strength more resistant *Intensity* is the key for maintenance

Why do we have muscle spindles?

Important in posture Tells us where are body parts are in relation to the environment Helps us execute smooth & coordinated movement There are more spindles in muscles that do complex movement.

Blood supply with exercise:

Increase blood needed for the exercising muscle to deliver more oxygen. Do you remember how this comes about?? • Shunting blood to exercising muscles • Dormant capillaries will open • Vasodilation

Aerobic Training Adaptations

Increase in mitochondrial size and number in the aerobically trained muscle Increase in enzymes for aerobic metabolism Improves an individual's ability to oxidize FA & carbs Increase in the size of the muscle fibers due to hypertrophy increase in capillary density in the trained muscle (more • More oxygen delivery and gets rid of lactic acid Improves the ability to remove metabolic byproducts (LA) and heat.

Increase capacity of ATP-PC system and anaerobic glycolysis to generate ATP by

Increase storage of anaerobic substrates (ATP, PCr, glycogen) Increase amount and activity key enzymes Increased capacity to generate high levels of blood lactate during all-out effort o ↑ levels glycogen and enzymes o ↑ motivation and tolerance to "pain" in fatiguing physical activity

Enhanced Capacity to Generate ATP Aerobically is due to:

Increased mitochondria number and density Adaptations in *both* muscle fiber types, enhancing each fiber's existing aerobic capacity and lactate threshold level Improved ability to oxidize fatty acids Enhanced capacity to oxidize carbohydrate Increase in capillary density Increase enzymes

Anaerobic Overload

Increasing intensity or duration of work interval Decrease length or relief interval • Shorter increases use on AG; longer > ATP-PC system because allows for restores ATP-PC Change type of relief interval • More active work relief >AG; less active or rest relief > ATP-PC Increase number of repetitions Increase frequency per week

Factors Affecting the Aerobic Training Response

Initial level of aerobic fitness • If low state of fitness considerable room for improvement; high level window is small Training intensity • % of HR • % or VO2 max • RPE Training frequency Training duration

Training Phases

Initiating a Training Program • Teaching them how to exercise Improvement Stage * Keep overloading Maintenance * Maintain intensity; can decrease frequency and duration by 50% but must main intensity

Four factors help to formulate the anaerobic interval training prescription:

Intensity of exercise interval Duration of exercise interval Duration of recovery interval: time in between o Work relief: mild to moderate work > reliance on AG o Rest relief: light exercise o Complete rest: no activity-seldom used • Repetitions of exercise-recovery interval

Motor Unit

Is the functional unit of movement; It is defined as the AMN (anterior motor neuron) and all the muscle fibers it innervates A whole muscle contains many motor units that are scattered throughout the muscle. The ratio of muscle to nerve is generally related to a muscle's particular movement / function. • Fine vs. Gross Each mm fiber receives input from one motor neuron

Low, Moderate, & High RMs

Low RMs (allow fewer than six reps) provide the most strength and power benefits Moderate RMs (6-12 RM) provide moderate strength, power and endurance High RMs (20 +) provide primarily muscular endurance gains with few strength gains

Case 3: 25 yr old wishes to train for 10k race

Mode o running Intensity o 70-75 VO2 max o 13 RPE (normal & healthy) Duration o at least 30 mins Frequency o 3x a week

Muscle Spindle Anatomy

Most abundant proprioceptor Contains modified mm fibers contained in a capsule with a sensory nerve spiraled around the center. • These modified fibers are called intrafusal fibers. Center portion of the spindle is not capable of contracting but the 2 ends contain contractile fiber and are capable of contracting and shortening • It is attached in parallel to the extrafusal muscle fibers of the muscle.

Muscle Structure

Muscle: # of fasciculi Fasciculus: bundle of mm fibers Mm fiber Myofibril: smaller functional unit of the muscle fiber Myofilament: made up of 2 main proteins Actin and Myosin and also other 12-15 other proteins including troponin and tropomyosin

Considerations Prior to Exercise Prescription

Must determine person's fitness level Risk factor assessment (lab) Resting vital signs Be aware of signs/symptoms of C/V, pulmonary or metabolic disease and disorders (lab) Be aware of medication that may blunt exercise response Need to know absolute and relative contraindications to exercise and exercise testing PUT IN ACSM Need to be aware of normal and abnormal response to exercise and when exercise should be terminated (lab)

Do all motor units within a muscle fire at the same time?

No, not all motor units within a muscle fire at the same time Must have different ways to recruit for various activities *Slow switch motor* units have the lowest threshold for activation and are recruited first and selectively recruited during light to moderate effort Increase physical effort needed will progressively recruit more *fast twitch* fibers

Acute Muscle Soreness

Occurs during or directly after strenuous exercise performed to exhaustion. Sensation is characterized by feeling of burning or aching in mm • Decrease blood flow and O2 • Increase LA and potassium • Described as burn or ache • Goes away quickly once blood and O2 restored-cool down

Training Mistakes

Overtraining: • majority of training injuries result of over training Under training: • Exercises and work intensities not specific Improper Progression • Acute Muscle Soreness • Delayed Onset Muscle Soreness (DOMS) Not Tapering • must have time to resynthesize glycogen and repair muscle damage (3-21 days)

Plyometrics

Plyometric training drills attempt to use the inherent stretch-recoil characteristics of the neuromuscular system to bring about muscular power of specific muscles Recommendation: 1) follow each activity with complete recovery 2) use a yielding surface with good footwear 3) skills program 4) 1-3 days/week 15-20 minutes

DOMS Prevention and Treatment

Prevention • Best is to exercise regularly • Proper nutrition, rest, progression o (no more than 10%/wk.) • Proper warm up and cool down • Literature variable Treatment • Evidence is mixed; no definitive treatment • Can continue to train • Modalities: ice, ES • Massage-no evidence that it helps • Compression sleeve; some evidence that decreases edema • Topical salicylate cream-analgesic effect

Golgi Tendon Organs

Proprioceptors found in the tendon near the junction of the muscle Connected in series (attached end to end) to extrafusal fibers Detect differences in *tension* generated by the muscle NOT length • 1. responds to tension created in the muscle when it shortens • 2. responds to tension in the muscle when it is passively stretched Protects the muscle and tendon from excessive load; reflex inhibition • If it detects a the change in tension (from shortening or passive stretch) it fires causing a inhibitory influence on the motoneuron reducing the tension in the muscle

Aerobic Psychological Benefits

Reduction in state of anxiety ↓ in mild to moderate depression Reduction in neuroticism Adjunct to professional tx of severe depression Improvement in mood, self esteem, and self concept

Periodization

Refers to the organizing of resistance training into phases of different types of exercise done at varying intensities and volumes for a specific time period.

Cool Down Function

Remove lactic acid in blood and muscle to enhance recovery period Prevent pooling of blood in extremities - facilitate venous return Return HR and BP to normal Metabolism returns to resting level

Anaerobic Training Method: Interval Training

Repeated bouts of high intensity work alternated with recovery periods. Training intensity of actual work performed is increased. Simulates the variation in energy transfer intensity through specific spacing of exercise and rest periods

Muscle Spindle Function

Responds to stretch on a muscle (extrafusal fibers) and *through reflex action initiate a strong muscle action to reduce stretch.* Controls changes in the length of the extrafusal fibers Provides sensory information about *changes in length and tension of the muscle.* *Degree of stretch*

CP-ATP System

Short duration - high intensity 1:3 ratio 25-30 reps (10-30 seconds work/ 30-90 seconds rest) Goal: max overload phosphate pool sufficient restoration of CP/ATP

Activity that requires an increasing force

Size Principle o with more rapid or powerful movements, motor neurons with progressively LARGER axons (type II) are recruited. Performance/Athletes o the ability to control motor unit firing pattern is the major factor that distinguishes skilled verse unskilled performance, and specific athletic groups.

General Resistance Training Recommendations

Standard • 3-4 times/week, 3 sets of 10 reps ACSM Guidelines: • Sets: One set • Reps: 8 - 12 Reps performed • Intensity: near fatigue • Mode: free weight or weight machines for 8 - 10 exercises involving the major muscle groups (buttocks, quads, hamstrings, chest, back, shoulder, trunk) • Frequency: 2 times a week; 20-30 minutes (less than 60) • Duration: 20-30 minutes (less than 60)

Isometric Training

Static exercise Gains are +/- 20 degrees on each side of joint angle Best if do multiangle; 4 or 5 joint angles through a ROM or every 20 degrees Maximal contractions needed to bring about changes in strength Procedure variable • Hold 3-10 seconds (8-10), rest 20 seconds repeat 5-10 times (other 20 reps), 5sets 5x/wk o Takes 7 seconds for maximum contraction to occur • strength: hold 5 seconds, repeat 5-10 reps and do max of 5 sets and 5x a week; other research says longer 4 sets, 1 rep and 30 seconds held

DOMS S/S

Tenderness to palpation of mm belly or M/T junction Soreness increases with passive lengthening or active contraction of involved mm Local edema or warmth Mm stiffness reflected by spontaneous mm shortening before onset of pain Decrease in ROM b/c mm soreness Decrease mm strength prior to onset of soreness that persists up to 1-2 wks. after soreness resolved

Degree of Pennation

The degree of pennation directly affects the # of sacromeres per cross sectional area; allows for "packing" of large number of fibers in a small area Greater the pennation the greater the # of fibers, shorter fibers and less ROM **muscles with greater pennation have slower shortening velocity but generate greater force than fusiform muscles.

Crossbridge Detachment

The detachment of the myosin crossbridges from the actin is brought about when ATP is joined to the Actomyosin complex. This causes the crossbridges to detach. *Tropomyosin and Troponin: they are proteins that surround the helix shape of the actin. They regulate the "make and break" contact of the crossbridges.*

Anaerobic Adaptations & Goals

The physiological responses that result from anaerobic training occur mostly within the skeletal muscle Overload principle requires that the training intensity be near maximum Increase capacity of *ATP-PC system and anaerobic glycolysis* to generate ATP

Overload

The training program must stress the system above the level it is normally accustomed; will stimulate specific adaptations Can overload by manipulating: frequency, intensity and duration or combination of these factors Needs to be individualized and progressive • A planned, systematic, and progressive increase in training to improve performance *For strength improvements to occur muscles have to be taxed beyond their regular accustomed loads

Rhythmic Exercise

There is a fluctuation in blood flow. Blood flow decreases during contraction and increases during relaxation. • (Milking action)

Neuronal Facilitation

This ability to "disinhibit" leads to FULL activation of muscle groups during all out exercise Important in strength and power activities • Allow you to facilitate all the muscles you need to lift 600 lbs over your head one time Thought to account for the rapid and highly specific strength increases noted during the early stages of strength training • First 4 weeks is all neuro, after that you start to see physiological

Training Program Goal

To cause biological (structural and functional) adaptations to improve performance in specific tasks Need to take into account personal goals An effective training program safely optimizes an individual's ability to achieve his or her own measure of success or improvement Consider underlying conditions

Muscle spindle can activate the Alphamotor neurons that cause the extrafusal mm to contract in 3 ways:

Tonic Stretch Phasic Stretch Gama System/Loop

Signs of Muscle Fatigue

Uncomfortable sensation in the muscle, pain, cramping Tremulousness in the contracting muscle Active movements jerky, not smooth Inability to complete the movement Substitution • Compensation Inability to continue low intensity physical activity Decline in peak torque with isokinetic testing • When pt is pushed too far

Individual Difference

Variation in training response; due to an individual's level of fitness and genetics General approach for males and females are the same Need to match training with level of fitness • A beginner would make greater relative gains due to greater adaptation window for improvement Need to match training with maturation • age doesn't equal maturity

How do we determine which Dynamic Constant External Resistance Training method to use?

a) patient characteristics b) individual preference c) space availability d) cost e) level of training

Strength of Muscle Depends on

a. Cross-sectional area b. Fiber type composition c. Overall length of muscle d. Bony lever's arrangement e. Recruitment f. Speed of muscle contraction

Absolute (fixed)

all subjects required to lift a common weight or at a pace they can't keep up at a certain workload (training you can do more) total force in kg or lb. o Tess & Gian work with 20 lb weight

CNS Fatigue

alteration in neural transmission during exercise by altering level of CNS transmitters PO2, PCO2 all out exercise - brain will stop muscles from activating

Relative

assigned a fixed percentage of max strength; relative takes into consideration your 1RM o Tess works with 20 lb weight and Gian works with 120 lb weight *relative intensity varies with age, sex, physical conditioning and health status

Motor Unit Physiology

can be classified based on three physiologic characteristics of the mm fibers they innervate. • I. Twitch characteristics • II. Tension characteristics • III. Fatigability

Isotonic Training

change in muscle length a) Dynamic form of exercise that is carried out against a constant or variable load as muscle lengthens or shortens through range. b) the weight that is lifted can be no greater than what the muscle can lift at its weakest point c) If you want to develop strength, use progressive resistance exercises in the overload zone

* Oxford Technique

determine 10 RM perform: • 10 reps @ 100% 10 RM • 10 reps @ 75% 10 RM • 10 reps @ 50% 10 RM believed to decrease effects of fatigue

DAPRE Technique (daily adjustable PRE)

determine working weight of 6 RM perform: • Set 1: 10 reps @ 50% working weight • Set 2: 6 reps @ 75% working weight • Set 3: as many reps as possible @ full working weight If you can do: • 0-2 reps, decrease 5-10# for 4th set • 3-4 reps, decrease 0-5 # • 5-6 reps, perform at same weight perform 4th set at adjusted working weight

Isokinetic Training

dynamic exercise in which muscle contraction is performed at constant velocity Should lead to greatest improvement in muscle performance because: • greater number of motor units are activated • greater overload • must have high motivation though

**Initiation Phase

exercise with a buddy variety (indoor/outdoor, leisure time) make it part of schedule start conservatively wear comfortable clothing watch environmental conditions drink fluids stop if you feel shortness of breath, chest pain, unusual fatigue, dizziness, fainting, or severe pain

Type IIx

falls midway between it's a and b counterparts in physiologic and metabolic characteristics

Fast Twitch: Type IIb

high force and Fast Fatigue • (Type IIb)(Fast Glycolytic FG) • All Glycolytic fibers have the greatest anaerobic potential

Endurance Reps & Set

high volume 15-25 reps at low intensities and short rest periods (1-2 mins) 1-2 sets (untrained) 2-3 sets (trained)

Tropomyosin

is distributed along the length of the actin filament in the groove formed by the double helix. *It inhibits actin and myosin interaction or coupling and prevents permanent bonding of the actin/myosin filaments*

Troponin

is embedded at regular intervals along the actin strands has a high affinity for calcium ions (CA++) Calcium ions and troponin combine. The troponin then acts on the tropomyosin moving it deeper into the groove, thus exposing or uncovering the actin. The actin and myosin interact at the crossbridges and the myofibrils slide past each other.

Slow Twitch

low tension , and fatigue resistant • (Type I)(Slow Oxidative)

Synchronous Recruitment

many units recruited simultaneously o all at one time Weight lifting

Fast-Twitch: Type IIa

moderate force and fatigue resistant • (Type IIa) (Fast Oxidative-Glycolytic FOG) • More mitochondria • these are intermediate speed fibers • have both anaerobic and aerobic capacity

Aerobic Intensity

most critical • 55-70% of HR training range; 70% represents moderate activity without discomfort for most healthy people • *It has been shown that aerobic endurance training of fewer than 2 days/week at less than 40-50% of VO2 max and for less than 10 minutes not a sufficient stimulus.* • Training at a higher intensity has been shown to improve VO2 max; as intensity increases so does improvements in VO2 max

Joint Receptors

proprioceptors • are found in tendons, ligaments, periosteum, muscle and joint capsules • supply input to CNS concerning joint angle, acceleration of the joints and the degree of deformation brought about by pressure • sense of awareness of body limb position and posture

Muscle Power

rate of performing work per unit time; rate at which muscle contracts (speed) speed & strength

Nutrient Fatigue

reduction in *muscle glycogen* of the active muscle fibers produces fatigue with prolonged submaximal exercise; occurs even though sufficient oxygen is present. Depletion of PCr and decline in nucleotide pool (ATP + ADP + AMP) also accompanies the fatigue state in prolonged exercise o No energy source

Isotonic Contraction

refers to a concentric or eccentric contraction in which a constant weight/load/tension is moved through a range of motion at variable speed • 5 lb dumb bell and go slow or fast Constant resistance, varying load; the heaviest weight lifted is at the weakest point of the muscle

Length Tension Relationship

refers to the amount of force that a muscle can exert in relation to its length. When sacromere is short the actin filaments overlap thus there is a reduction in the number of actin sites available to bind with myosin crossbridge Fewer actin/crossbridge available for binding the less force produced When the sacromere is relatively too long potential force is also reduced because the actin sites are beyond the reach of the myosin crossbridges **peak force production is usually seen at resting or slightly greater than resting length (optimal binding of actin & myosin)

Asynchronous Recruitment

some fire while other units recover Riding a bike

Specific Adaptations to Impose Demands (SAID)

specific exercise elicits specific adaptations to promote specific training effects that produce specific performance improvements • Mm strength • Mm endurance • Aerobic • Anaerobic Also refers to the specific movement system trained

Isometric Contraction

static contraction tension developed without a change in external length of the muscle tension in the cross-bridges equals the resistance to shortening and the muscle length remains relatively constant

Sarcomere

the functional unit of the muscle cell Actin and Myosin are within the sarcomere • Actin: is the thin filament. a It has 2 other proteins on it Tropomyosin and Troponin • Myosin: is the thick filament. Large projections or crossbridges extend from the thick myosin filaments to the thin actin filaments

Strength Reps & Sets

very low volume 1-6 reps at high intensity (85-100% 1RM) 1-3 sets (untrained) 3- 5 sets (trained)

Neuromuscular Junction Fatigue

when an action potential fails to cross from the motoneuron to the muscle fiber.

Intensity: Heart Rate

• % of Max HR: 220-age or from stress test • Karvonen Method (HRR method) • Max HR arm 10-15 beats lower than leg o Smaller mm mass • Swimming 13 beats lower o Horizontal position o Cooling effect of water

Overload Application

• 1. Increase load or resistance • 2. Increase number of repetitions • 3. Increase speed of muscle action o inversely related to force o last thing that you overload If you exercise any muscle at a higher intensity, near it's max force generating capacity, it will become stronger.

Anaerobic Interval Training: Frequency

• 3-4x/week with 1 maybe 2 sessions per day; devote less than 10% of session time 8-10 wks..

Cool Down

• 5-10 minutes at a lower intensity; time depends on person's fitness level • Static stretching

Warm Up

• 50-60% Max HR (5-10 minutes)-raise HR 20 bpm • Time depends on the person's age and fitness level • Large muscle groups those used in planned activity • Mild dynamic stretching (not static)

Temporal Summation

• A number of sub-threshold impulses can arrive in rapid succession to presynaptic terminal causing depolarization.

Muscle Fatigue with Aerobic

• Accumulation of LA • Lack of oxygen • Increase in H+ ions • (all alter muscle function by changing environment)

Transverse Tubule System or T- system

• Are interconnecting channels that run *perpendicular* to the myofibril • T-tubules pass through the fiber and open externally from the inside of the muscle cell. • T- tubules are situated between 2 sarcoplasmic channel *o Brings stuff from the outside to the inside*

Somatic nerves

• Arise from Anterior Motoneurons • Innervate the skeletal muscle • Firing of these neurons is always excitatory to the muscle and cause muscle to contract.

*Anaerobic Interval Training: Duration

• CP-ATP System: 25-30 reps of 30s or less • An. Gly. System: 10-20 reps of 10s-2 min+ • Do 3-6 bouts/session

Anaerobic Interval Training: Intramuscular high-energy phosphates

• Engaging specific muscles in repeated 5- to 10-second maximum bursts of effort overloads the phosphagen pool • Activity or sport specific

Adaptations guidelines

• First 2 months strength gains due to neural input (CNS motor pattern) • 8-12 weeks increase size and strength due to: increase contractile proteins increase size of myofibrils in fiber increase number of myofibrils in fiber • if overload is exceeded the ability to contract may be decreased and loss of lean tissue may occur • Circuit training good for cardiac patients - intensities 40-60% of 1RM; some up to 75% • Injury: after extended period of time off: light load (50-60% of 1RM)- increase intensity gradually Pain and inflammation as guideline

Exercise Prescription

• Frequency: how often in a given period of time • Intensity: how hard • Duration: how long • Mode: type of exercise

Disadvantages of Eccentric Contraction

• Greater DOMS • Greater amount of resistance needed to overload muscle • Excess stress placed on CV system when eccentric exercise is performed against heavy resistance

*Anaerobic Interval Training: Recovery

• HR should drop below 120 bpm near end of recovery interval

Fast Twitch Type II

• High capacity for electrochemical transmission of action potentials • High myosin ATPase activity • Rapid calcium release and uptake by an efficient sarcoplasmic reticulum • High rate of cross bridge turnover Spring, weight lifting, jumps

Slow Twitch Type I

• Low myosin ATPase activity • Slow calcium handling ability and shortening speed • Less well-developed glycolytic capacity than fast-twitch fibers • Large and numerous mitochondria running, biking

Aerobic Training Methods: Long slow distance

• Moderate intensity long duration • Intensity below lactate threshold 70-85% of max HR, 60-70% of max VO2 • Want comfortable pace • *RPE 13-14*

Eccentric Contraction

• Muscle action where the muscle lengthens while still creating tension Load is > than tension Used in resisting gravity- walking downhill or downstairs certain sports like wrestling Generates more force than concentric Consumes less oxygen and energy stores

Goals of Resistance Training

• Performance: power, strength and endurance (hypertrophy) • Increase the max force that can be generated by a muscle group.

Aerobic Training Methods: Interval Training

• Repeated very high intensity short duration: near lactate threshold 85-100% MHR • 1:1 ratio work to rest interval

Spatial Summation

• Simultaneous stimulation of different presynaptic terminals of the same neurons which in turn will increase output

*Anaerobic Interval Training: Intensity

• THR 5-15% HR at Lactate Threshold o (85-100% MHR) as you train must continue to increase pace to be above lactate threshold

Anaerobic Interval Training: Lactate-generating capacity

• To improve energy transfer capacity by the short-term lactic acid energy system, training must overload this aspect of energy metabolism (10-60 sec)

Overreaching

• Unplanned, excessive overload with inadequate rest. Poor performance is observed in training and competition. Successful recovery should result from short-term interventions

Overtraining Syndrome

• Untreated overreaching that produces long-term decreased performance and impaired ability to train. Other associated problems may require medical attention.

When a muscle shortens while lifting a constant load, the tension developed over a range of motion depends on the:

• a. length of the muscle • b. angle of pull of the muscle • c. speed of shortening

Crossbridges

• during contraction each crossbridge undergoes many repeated but independent cycles of movement. • At any one time only 50 % of the bridges are in contact with actin. • When actin and myosin are in contact it forms a complex called Actomyosin. • Crossbridges combine, detach, combine to a new site.

Velocity

• force is inversely related to velocity • the faster the movement the less force production

Phasic Stretch

• holding a book and another book is added this causes a greater stretch to the muscle spindle and it senses this increase in stretch and sends info back to the spinal cord • The spinal cord in turn activates more AMN to compensate. Responding to the RATE or VELOCITY of the change in length not the length per se.

Tonic Stretch

• i.e. holding a book in one position. • There is a steady mm contraction to hold it. The spindle is responding to the FINAL length of the muscle fiber.

Intracellular Tubule System

• is an extensive network of interconnecting tubular channels within the muscle fiber (lies *parallel* to the myofibrils) • This is the sacroplasmic reticulum. The lateral end of each sacroplasmic tubule terminates in a sac-like vesicle that store calcium ions

Sarcoplasm

• is the liquid protoplasm of the cell • contains the contractile proteins, enzymes, lipids, glycogen particles, nuclei and other special cellular organelles.

Sarcolemma

• lies under the endomysium • it is a thick elastic membrane that encloses the muscle fiber's content

Potential causes of DOMS

• minute tears in the muscle fiber • osmotic pressure changes that produce fluid retention in the surrounding tissue • muscle spasm (overuse/depletion of mineral) • overstretching - *disruption of connective tissue* • acute inflammation • Alteration in the cell's mechanism for calcium regulation • Combination of the factors

Concentric Contraction

• muscle shortens and produces tension throughout the ROM Load less than tension so muscle will shorten Greater motor unit recruitment than eccentric

Cross section

• muscles that have larger cross-sectional areas have a larger number of sacromere in parallel which allows for more connection of crossbridges to bind with actin producing more force • longer muscles have more sacromeres in series and thus there is an increased potential for shortening (all shorten at once)

Aerobic Duration

• no threshold per workout exists it depends on the intensity and fitness level; 20-30 mins • inversely related to intensity

Training Load

• number of repetitions times the weight lifted per repetition o 5 lb weight x 10 repetitions

Repetition

• one complete exercise movement; usually consist of concentric and eccentric action or one complete isometric action the amount of weight that is lifted

Isometric Training Disadvantages

• only build strength at specific joint angle • may not safe for hypertensive: watch valsalva o hard to motivate since no feedback o no hypertrophy or power development o doesn't resemble sport skill o doesn't improve motor performance

Set

• pre-established number of repetitions performed

Isometric Training Advantages

• small space • no equipment • rehab immobilized joint • less apt to cause soreness

Proprioceptors

• specialized sensory receptors in the muscles, joints and ligaments that are sensitive to stretch, tension and pressure. • they rapidly relay information concerning muscular dynamics and limb movement to the conscious and unconscious portions of the CNS for monitoring. • *this is important for coordination of movement, maintaining muscle tone and body posture*

Repetition Maximum (RM)

• the greatest amount of load a muscle can move through the available range of motion a specific number of times

Intramuscular Pressure

• the pressure put on the vessels that supply the muscles, when intramuscular pressure gets to a certain point it squeezes on the muscle stopping blood flow (call this occlusion) • It occurs at different percentages of maximal contraction.

*Triad

• the repeating pattern of 2 sacroplasmic vesicles and T-tubule in the region of each Z line. • *The triad and the T-tubule system spread the action potential (wave of depolarization) from the fibers outer membrane inward to the deep region of the cells.*

Gender Differences in Muscular Strength

• the sex difference in strength is eliminated when force production in men and women is compared on the basis of x-section are of muscle • human skeletal muscle can generate between 3-8 kg of force per cm squared of muscle cross section, regardless of gender; however, capacity depends on muscle arrangement and architecture; greatest force is found in individuals with largest muscle cross section (strength is expressed in unit area of muscle cross section

Gamma System/Loop

• the spindle can also contract as a result of direct stimulation of Gamma neurons by the higher centers in the cerebral cortex • (Cerebral cortex....pyramidal tract...spinal cord...Gamma efferent..spindle...Spinal cord AMN...efferent ...muscle )

Training Volume

• total work performed in a single training session • Number of sets performed x the training load o 5 lb weight x 10 repetitions x 3 sets

Aerobic Frequency

• typical 3 days for 6 weeks to see improvements; with rest in between; frequency depends on intensity; daily for wt. loss but at lower intensity

Aerobic Pulmonary Adaptations

↑ TV at max exercise ↓ resting and submaximal RR ↑ pulmonary ventilation during max exercise ↓ fatigue mm Ventilatory mm produce less lactate Result is ability to breathe deeper and less often so more efficient

Aerobic Cardiovascular Adaptations

↑maximal cardiac output ↑ stroke volume ↑ plasma volume ↓resting HR ↓ submaximal HR ↑ RBC mass ↑ left ventricular cavity size ↑ A-V difference ↑ total hemoglobin Better bf distribution to active muscles ↓ BP at rest and submax exercise Improved coronary blood flow

Aerobic Muscle Adaptations

↓ rate of blood lactate formation during activity ↑ rate of lactate clearance Combination of the above


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