Lecture 2 Flashcards

Question

What are 2 proposed periodization models?

Answer 1

1) UNDULATING (non-linear) 2) TRADITIONAL (linear) No consensus as to which method is better. - UP models seems better than TP model to improve maximum strength performance, but not power, muscular endurance, isometric strength and muscle hypertrophy (Caldas et al., 2016)

Answer 2

* Mesocycles with different objectives (ex: hypertrophy, strength, etc) – Week 2 microcycle optional (often non necessary) – If individual trains only 3x/week, separate sessions not necessary (full-body workouts appropriate)

Answer 3

Refer to slide 51 on lecture 2

Answer 4

MUSCLE AGONISTS * Main muscles used for movement (‘prime mover’; contracting muscle) – Ex: hip flexion agonist: iliopsoas MUSCLE ANATOGONISTS * Muscles that resist a movement (main muscle that does opposite of the action it is resisting) – Ex: hip flexion antagonist: gluteus maximus MUSCLE SYNERGISTS * Muscles that create a movement together – Ex: iliacus, psoas major, rectus femoris

Answer 5

A lever consists of: a) A rigid structure (bone) b) A force acting upon it (muscle) to produce angular motion c) A fulcrum (joint) d) A load or resistance that is placed on rigid structure

Answer 6

1) first class lever(ex.tricep dip) 2) second class lever(ex.calf raise) 3) third class lever(ex.bicep curl) Refer to slide 54 of lecture 2

Answer 7

MA > 1 (effective lever) MA = 1 (efficacy = nil) MA < 1 (ineffective lever)

Answer 8

Most muscles operate with a mechanical disadvantage. – Force exerted by muscle greater than force applied to muscle

Answer 9

* Tendon insertion can vary amongst individuals. – Some individuals have a mechanical advantage based on their tendon insertion placement (greater strength with further distance from fulcrum) – Other individuals with tendons inserted closer to the fulcrum have a greater kinetic advantage

Answer 10

* Neuromuscular control * Cross-sectional area of muscle * Muscle fibres orientation * Muscle length * Joint angle * Muscle contraction speed * Joint angular velocity * Strength-mass ratio * Height

Answer 11

* The unconscious trained response of a muscle to a signal regarding dynamic joint stability. – Influences maximal strength by determining the quantity and type of motor units that are involved during a muscle contraction (recruitment) as well as the frequency at which these motor units are stimulated. * Strength increases with: – Number of recruited motor units – Size of recruited motor units – Frequency/speed of stimulation of motor units * The majority of the adaptations that occur during the first weeks of training are due to nervous system adaptations.

Answer 12

* Muscle size (diameter) * The strength a muscle can produce (all factors equal) depends on the diameter of the muscle fiber rather than its overall volume Ex: - Two athletes (5’, 6’) who have the same %BF also have the same bicep circumferences - The 6’ (heavier) athlete has longer muscles than the 5’ athlete, therefore a higher muscle volume. - However, the strength of these two athletes should be similar as the circumference of the biceps is similar.

Answer 13

* Refers to sarcomere alignment with regards to the direction of the tendon or the longitudinal axis of the muscle * A muscle with pennate fibres es a muscle whose fibres are oblique to the tendon. – The angle of pennation is defined as the angle between the muscle fibres and the imaginary line between the origin and insertion of the muscle (0 degrees = no pennation)

Answer 14

* Several muscles have a pennate orientation, but very few are greater than 15 degrees * The angle of pennation increases muscle shortening.

Answer 15

Hereditary factors? – Can explain differences in strength between individuals with same muscle size * Hypertrophy increases the angle of pennation and explains in part the increase in strength gains with training * The muscles with the greater angles of pennation are a greater proportion of parallel sarcomeres which increases the capacity to generate strength but decreases contraction velocity – Parallel fibre orientation = strength (ex: psoas major) – Orientiation in series = speed of contraction (ex: rectus femoris)

Answer 16

* Refers to the degree of overlap of actin and myosin filaments based on the level of muscle contraction * The strength potential is at its greatest when the muscle is at its resting length

Answer 17

* All human movements are caused by a rotation around an axis within the joints – therefore the strength of a joint is generally discussed in terms of moment of force (torque) T=F·r·sinƟ * Torque is dependent on sin (the angle formed between the muscleƟ action and the segment on which it is attached). With movement, the angle between the tendon and the segment changes and can explain, in part, the changes in strength throughout full range of motion.

Answer 18

* A greater contraction duration (decreased speed of contraction) allows for a greater generation of strength Ex: * Vertical jump with and without arm involvement

Answer 19

* Torque varies with angular velocity (rotation) of a joint – Decreases with a greater angular velocity (concentric contraction) – Increases with velocity for eccentric contractions up until 90o/s, and gradually decreases thereafter – Greater strength capacity with eccentric contraction – Athletes ‘cheat’ when using this technique * Ex: bicep curls – Athletes extend their backs (isometric or eccentric biceps contraction)

Answer 20

* Athlete’s ability to accelerate (create movement) with their own body * Especially important for activities such as sprints and jumps, or sports that have a weight qualification * If an athlete increases their muscle mass by 15% but their strength by only 10%, they lose their ability to generate body acceleration by decreasing their strength-mass ratio * Athletes of short stature have a greater strength-mass ratio because with taller (and heavier) athletes, it is more difficult to increase the cross-sectional area (strength) proportionately to the greater mass of a tall athlete * Athletes that are shorter/slimmer are often faster * Please refer to Strength-Mass Ratio * Strength is proportional to the muscle’s cross-sectional area (2) * Muscle mass is related to volume (3) * Therefore as muscle volume increases, muscle mass increases more rapidly than strength (x3 vs x2)

Answer 21

* Gravity * Inertia * Friction * Aerodynamics & Hydrodynamics * Elasticity * Negative work and power

Answer 22

* Force due to gravity = weight * F = ma – Newton’s Second Law * Weight vs mass * a = -9.81m/s2

Answer 23

* Gravity (force always downwards) * Torque=F·r·sinƟ – Torque changes based on the horizontal distance of the force with regards to the pivot point

Answer 24

* Low bar squat vs high bar squat – The lower the bar is during a squat, the more the athlete needs to flex their trunk to ensure the centre of mass is above their base of support. * The posterior muscles need to work harder to maintain this posture and prevent the athlete from falling forward. * The athlete leans forward during a back squat as the bar lowers, the weight is horizontal to the knee, decreasing the strength needed for the quad to lift the weight. * Inverse relationship for the back and glutes.

Answer 25

* From a biomechanical perspective, the further the load is from the axis of rotation, the greater the required moment of force to lift the load (↓ moment of force of the muscle). – When the muscles are at a mechanical disadvantage, the muscle recruitment with the greatest mechanical advantage occurs the fastest. * Front squat – The glutes and extensor muscles of the hip are at a mechanical disadvantage. The quads are at a greater advantage therefore they are more recruited to complete the movement. (The opposite occurs for back squat) * When you consider the effects of gravity on posture, and the position of the load with regards to the axis of rotation and the involved muscles, you can vary the degree of muscle recruitment for a same movement.

Answer 26

Contrarily to gravity, the force of inertia can act in all directions * An acceleration is present at least at the beginning and ends of resisted movements (begin movement and slow down movement) * The athlete decelerates the movement either by: a) Reducing the force exerted against gravity (upwards) b) Using antagonist muscles * In each condition, the effects on the agonist muscles during deceleration are smaller than that during acceleration I=L/w

Answer 27

* In explosion exercises, there is a greater resistance at the beginning of movements than at the end * Heavier loads are easier to manoeuver with greater acceleration * Can be used to ‘cheat’ or to sollicit different muscle groups – Ex: using your hips to start a bicep curl – Ex: used to work abdominal muscles eccentrically

Answer 28

Fr= K·FN * K = coefficient of friction between two surfaces * Exercises that use friction as resistance – Stationary bicycle – Weighted sled * The coefficient of static friction is typically greater than the coefficient of friction during movement – Therefore more force is required to start a movement than to continue it

Answer 29

* The force of resistance that occurs when an object moves through a fluid or air * Swimming * Rowing * Golf * Sprinting * Discus Throw * Baseball * Tennis

Answer 30

FORM DRAG VS SURFACE DRAG * Surface drag (resistance): the friction a fluid/air passes along an object * Form drag (resistance): the way a fluid/air passes against the front or back of an object passing through the matter (cross-sectional area has the greatest influence)

Answer 31

* Fr= K·x – K = elasticity constant – X = change in length * The greater you stretch the elastic, the greater the resistance LIMITATIONS * Minimal resistance at the beginning of the exercise; a lot of resistance at the end of the range of motion – Rarely sport-specific movement pattern

Answer 32

* Power = F x velocity * If the force exerted is in the opposite direction to the movement (ex: lowering the db in a controlled manner), the calculated power will be negative (eccentric loading) – Therefore work and power will be ‘negative’ * During the concentric phase, the athlete (and their muscles) work with the load (positive)

Answer 33

maximus = large minimus = small Longus = long Brevis = short

Answer 34

Circular Convergent Parallel Pennate(uni-,bi-,multi-) Fusiform

Answer 35

Central & peripheral

Answer 36

Sensory division & motor division Somatic nervous system & autonomic nervous system Sympathetic division & parasympathetic division

Answer 37

Unipolar Bipolar Multipolar Sensory(afferent) Motor(efferent) Interneurons

Answer 38

Voltage gated Ligand gated Mechanically gated

Answer 39

Electrical vs chemical synapses Electrical synapses use gap junctions Chemical synapses use neurotransmitters

Answer 40

Right and left atrium Right and left ventricle

Answer 41

Blood flows from higher to lower pressure Contraction increases the pressure Valves open/close according to pressure gradients Phase 1-atrial depolarization/contraction Phase 2-isovolumetric contraction Phase 3-rapid ejection Phase 4-reduced ejection Phase 5-isovolumetric relaxation Phase 6-ventricular filling

Answer 42

SA node AV node AV bundle(right and left) Purkinje fibers

Answer 43

ATP-PCR system(5-15 seconds) Glycolytic system(1-2 minutes) Oxidative system(long duration of time)