front 1 Balance and stability are used ______? | back 1 Interchangeably |
front 2 Resistance to disruption of equilibrium | back 2 Stability |
front 3 A persons ability to control equilibrium | back 3 Balance |
front 4 For a system to be stable and for one to maintain balanced two conditions must be met? What does this basically mean? | back 4 1. All linear forces acting on the body must be balanced Basically, the sum of all forces acting on the body must equal zero |
front 5 All objects at rest are in equilibrium | back 5 Equilibrium |
front 6 3 Types of equilibrium? | back 6 1. Stable Equilibrium |
front 7 The center of gravity must be _____ in order to disrupt object? The more the center of gravity needs to be raised, the more ____ required to disrupt object? As a result the object is more ______? Where might we see this in sport/exercise? | back 7 raised effort stable Athletic stance to lower COG |
front 8 When the center of gravity starts high and drops to a lower point? It
requires less ____ and | back 8 Unstable Equilibrium energy stable |
front 9 Object’s center of gravity does not change when the object’s position changes? Give an example? | back 9 Neutral Equilibrium Walking….changes a little but not much |
front 10 What are the 3 factors that can influence balance/stability? Describe the subcategories under each? | back 10 Physiological Factors- Proprioception Body Characteristics and/or Positioning- Center of
gravity External Factors- Environmental Conditions |
front 11 Proprioception is a term coined in ____? | back 11 1906 |
front 12 The ability to sense where our body is in space? Its a sense of ____ and _____? It is described to be _____? | back 12 Proprioception Sense of position & balance Cognitive/subconscious |
front 13 Kinesthesia is a term coined in _____? “kenein” =
_____? | back 13 1880 to move sensation |
front 14 Movement of body | back 14 Kinesthesia |
front 15 What is behavioral kinesthesia? | back 15 – learn movements so you know how they feel for future reference |
front 16 “Presently, “kinaesthesia” and “proprioception” are used practically synonymously to indicate the capability to appraise the configuration and movements of an __________.”? | back 16 organism’s body parts |
front 17 Proprioception provides information on the ____ and _____ of movement of one body part relative to another? What is an example of this? Who has better proprioception than average individuals? | back 17 location rate Close eyes and touch nose example…we know general location of space Elite athletes |
front 18 Proprioceptive sense informs..... | back 18 contracted tendons Change head...body |
front 19 Proprioception is often divided into what 3 senses? | back 19 Sense of Tension (resistance) Sense of Movement Sense of Joint Position |
front 20 The ability to appreciate force generated within a joint | back 20 Sense of Tension (resistance) |
front 21 The ability to appreciate joint movement (duration, direction, amplitude, speed, acceleration, timing of movements) | back 21 Sense of Movement |
front 22 The ability to perceive a presented joint angle and reproduce specified joint angles …close eyes, can you put your elbow at a 90 degree angle? | back 22 Sense of Joint Position |
front 23 Cumulative neural input to the CNS from a variety of specialized nerve endings | back 23 Proprioception |
front 24 Name 4 types of Mechanoreceptors? | back 24 Skeletal Muscle & Joint Receptors |
front 25 Proprioception also obtains information from what 2 things? | back 25 Vision |
front 26 Sensory input received from mechanoreceptors are integrated and appreciated at what three levels of the CNS? | back 26 Spinal level Brain Stem Higher levels such as cerebral cortex + cerebellum |
front 27 Can provide direct motor responses in the form of reflexes…reflex reaction | back 27 Spinal level |
front 28 Brain Stem: | back 28 afferent movement balance & posture |
front 29 Conscious awareness of movements – voluntary movements | back 29 Higher levels (cerebral cortex & cerebellum) |
front 30 Muscle spindle provide______ at all times? Why is this special? | back 30 continual feedback (only one that does this) |
front 31 What do muscle spindles do? Within muscle fibers as
_______ | back 31 Response to stretch….make muscle contract as a protective mechanism intrafusal fiber gamma |
front 32 Where is a Golgi tendon organ? What do they do? | back 32 found where muscle converts into a tendon regulate tension in muscle and tendon…as muscle contracts…this response causes muscles to relax to prevent tendon damage |
front 33 What would happen during too much muscle tension especially during isometric contractions? | back 33 Relaxation reflex by Golgi tendon - protective mechanism |
front 34 Where are joint receptors found? | back 34 Are found in capsules and ligaments around joints |
front 35 Muscle spindles and Golgi tendon organs are ____ receptors in _____ and _____ junctions | back 35 sensory muscle musculotendinous |
front 36 Muscle spindles are found where? | back 36 in muscle belly |
front 37 spindle fibers sense what? | back 37 stretch |
front 38 Golgi tendon organ are wrapped between what in the muscle? | back 38 collagen fibers |
front 39 Muscle spindles monitor _____ and prevent ______? Can be called what 2 types of reflexes? | back 39 muscle length overstretching Myotatic Reflex or Stretch Reflex |
front 40 Describe process of muscle spindles? Muscle spindles always maintain what? | back 40 extrafusal muscle fibers at resting length...sensory neuron is active and sends input to spinal cord....spinal cord integrates function....alpha motor neurons receive input and give it to extrafusal fibers which then gives it to muscle spindles...causing spppindles to contract due to overstretching constant state of tension...always firing overall: muscle stretch-afferent signals to spinal cord-efferent signals to alpha motor neurons-muscle contracts-firing rate of afferent sensory neuron decreases |
front 41 Describe briefly the process of the Golgi tendon organ? | back 41 muscle contracts-neuron fires afferent info to spinal cord which then sends back efferent info to the GTO and then the muscle relaxes and the load is dropped |
front 42 What do Cutaneous Receptors provide info for? Name 3 kinds? | back 42 Pain Pacinian Corpuscles, Hair Follicle Receptors and Touch Receptors |
front 43 Located deep in the skin | back 43 Pacinian Corpuscles |
front 44 Stimulated when hair on the body is deformed or touched | back 44 Hair Follicle Receptors |
front 45 Provide information about the surface of objects | back 45 Touch Receptors |
front 46 What is a feedforward reflex for posture? What about a feedback reflex? | back 46 The brain initiates movement and then postural disturbance is anticipated and therefore adjusted right away Body moves and then posture is disturbed and then feedback for unanticipated postural disturbance fixes the posture |
front 47 What 2 things improve proprioceptive ability? | back 47 Warm-up |
front 48 What 3 things decrease proprioceptive ability and explain a little bit why? | back 48 Exercise induced muscle fatigue |
front 49 Who had smallest amount of proprioceptive error in a study? | back 49 the exercised young |
front 50 Point about which all particles of the body are evenly distributed | back 50 Center of Gravity |
front 51 COG refers to a _____ direction, why? Another name for COG | back 51 vertical because gravity acts vertically center of mass |
front 52 COG is the ______ point of the body? Why? | back 52 balancing Due to the fact that is the point at which the sum of the torques acting on a body equals zero |
front 53 The location of the center of gravity of any object remains fixed as long as _____? | back 53 the body doesn’t change shape |
front 54 If a body changes shape, center of gravity may _____? | back 54 change location |
front 55 _______ results in changes in the location of the center of gravity | back 55 Locomotion |
front 56 Do males or females have lower COG? why? | back 56 Females have lower COG…junk in the trunk.. |
front 57 Center of gravity of humans in a neutral standing posture will vary depending on _____ + ____? | back 57 Body build |
front 58 COG for males? For Females? Why... ______differences, what about shoulder and hips? | back 58 Males: 55 - 57% of standing height Females: 53 - 55% of standing height Average height Broader shoulders (men) Wider Hips (women) upper body muscle mass Android Gynoid |
front 59 How does COG vary with age? | back 59 as you get older you hinge over and lower COG and moves it forwards…for kids their COG is high because they have big heads |
front 60 Weebles have very low ____? What does this mean? | back 60 COG....objects with low COG are less likely to topple down |
front 61 General location of center of gravity in human: __________ (during standing posture)? | back 61 Upper third of the sacrum |
front 62 Anything that increases the mass of a body above the original center of gravity will result in ______________? Give an example? This essentially does what? Therefore lowering what increases stability? | back 62 the center of gravity shifting upward Example: extending arms above head or holding a weight above original center of gravity This decreases stability Lowering the center of gravity will increase stability |
front 63 Body characteristics may improve or reduce ________ relative to COG? Give an example? | back 63 performance Boxers and Gymnasts lower their COG |
front 64 Center of Gravity must be __________ to maintain balance | back 64 over the base of support |
front 65 The part of the body in contact with the supporting surface and the intervening area | back 65 Base of Support |
front 66 What happens when you widen your stance? | back 66 Widen the distance between feet, widens the base of support |
front 67 Feet and all of the _______=base of support | back 67 space in between |
front 68 What can you do to the base of support too enhance stability when external forces are present? | back 68 change the shape of the support base |
front 69 To resist external forces widen the base of support in the direction of ________? | back 69 the external force |
front 70 To resist a force coming from the side, widen stance in the ______ plane? This will make you less stable though if the force comes from _____? Can use a _______ if the direction of the force is not known? | back 70 frontal the front combination |
front 71 So long as an object’s ______ falls within its base of support balance can be maintained | back 71 line of gravity |
front 72 The closer the line of gravity to______________ the more stable the object (in the absence of lateral external forces) | back 72 the center of the base of support |
front 73 As the line of gravity approaches the __________ the object becomes less stable? Once it passes this, _____ is lost and a new base of support must be formed | back 73 margin of the base of support stability |
front 74 We often ________ external loads to make sure the line of gravity remains close to the center of the base of support | back 74 counterbalance |
front 75 When external force is in line with gravity (vertical) we often lean
________ from the force | back 75 away Carrying a Suitcase and leaning to opposite side |
front 76 When the external force is lateral we lean _________? Example? | back 76 into the force Leaning into the wind |
front 77 _____ of a body is only a factor in maintaining balance when motion or an external force is involved | back 77 Mass or weight |
front 78 The amount of force needed to move an object is greater if the ____ is greater | back 78 mass |
front 79 Generally speaking, the greater the mass the greater the _______? | back 79 stability |
front 80 Depending on the condition, ______ may play a role in maintaining balance. Give 2 examples? | back 80 friction Icy pavement |
front 81 Friction is more of a factor when _____ is involved | back 81 motion |
front 82 When just standing COG points ________ down….as you walk you have a _____ force | back 82 vertically horizontal |
front 83 If the friction is not sufficient enough to oppose the line of force produced by the body what happens on ice? So what do people do? | back 83 the legs will slide out from under the subject causing them to fall People take short strides on ice to keep vertical force and to not fall |
front 84 Describe the Romberg Test? | back 84 Feet together, arms at side, eyes closed |
front 85 What does BESS stand for? This test utilizes ________? Name them and on what surfaces? Describe what you have to do and how this test works? Results are best utilized if compared to ________? | back 85 Balance Error Scoring System three stances Double, single, tandem on both firm and foam surfaces Athletes are instructed to remain motionless with hands on
hips for 20 seconds baseline data |
front 86 Assessent of balance that quantifies risk for future falls in elderly…uses a scoring sheet | back 86 Berg Balance Scale |
front 87 Best assessment for balance? | back 87 BESS |
front 88 point at which the force vector generated by the weight of an object is applied to the contact surface (ground) | back 88 Center of pressure |
front 89 slight shift in the line of gravity when standing | back 89 Postural Sway |
front 90 Postural Sway results in a change in ____________? | back 90 the center of pressure |
front 91 Postural Sway can be measured in what 2 ways? | back 91 Anterior to Posterior or Medial to Lateral |
front 92 Magnitude of Postural Sway may be impacted by what 7 things? | back 92 1. Age…older sway increases |
front 93 ____ of all Community-dwelling adults experience at least one fall yearly? Falling is the ____cause of death in over 65 age group | back 93 1/3 Sixth leading |
front 94 When there is a balance disruption, what must the body do? What initiates a response first? | back 94 Body must be able to determine what strategy to utilize in order to
control CoG |
front 95 Shifts CoG by maintaining feet and rotating body as a rigid mass about the ankle joints | back 95 Ankle Strategy for balance disruption |
front 96 ___________ or ________ are responsible for torque production about ankle (muscle) | back 96 Gastrocnemius or tibialis anterior |
front 97 __________ sway is counteracted by gastrocnemius and tibialis anterior? | back 97 Anterior/posterior |
front 98 Effective for slow CoG movements when base of support is firm and within LOS, also effective when CoG is offset from center and is used for minor changes | back 98 Ankle Strategy for balance disruption |
front 99 Relied upon more heavily when somatosensory loss occurs and forward/backward perturbations are imposed | back 99 Hip Strategy for balance disruption |
front 100 Hip strategy aids in control of motion through initiation of _____ and _____ motions at the hip | back 100 large rapid |
front 101 Effective when COG is near LOS perimeter and when LOS boundaries are
contracted by narrower base of support and is used when there is a
higher degree | back 101 Hip Strategy for balance disruption |
front 102 Utilized when COG is displaced beyond LOS…(line of stability) and a step or stumble is utilized to prevent a fall | back 102 Stepping Strategy |
front 103 Slowest system for balance disruption? | back 103 stepping strategy |
front 104 Muscle Response to Instability Results in a _______ to ______
Activation Pattern? | back 104 Distal to Proximal 90 – 100 msec…shorter reax time 120- 130 msec 130 – 140 msec…slowest of these three |
front 105 What is the new trend in exercise science related disciplines? | back 105 Functional Movement Assessments |
front 106 What are some of the most common FM assessments used currently? | back 106 FMS |
front 107 What is the foundation that all movement stems from? Its 2 subcategories? | back 107 Posture Static |
front 108 What is the most common movement pattern used by your clients every day? | back 108 Walking |
front 109 How individuals present themselves in stance | back 109 Static Posture |
front 110 How an individual is able to maintain posture while performing functional tasks | back 110 Dynamic Posture |
front 111 Powerful movements depend on optimal _____alignment and ______? The spine coordinates whole body power via proper execution of ___________? A weak foundation leads to ______? Perfect posture pays dividends by? | back 111 spinal... stability movements or exercises secondary problems elsewhere in the system reducing stress/loads |
front 112 Cervical spine gives ____ freedom of movement Thoracic allows ____ of your torso Lumbar spines provides _______ Sacrum provides ________ _________ act as a pivotal axes allowing movement integration between your legs, pelvis and spine. | back 112 your head rotation stability the base for your spine to sit on Sacroiliac joints |
front 113 Static Postural Assessment is the basis for identifying _____? | back 113 muscle imbalances |
front 114 Regardless of the several factors responsible for changes in joint alignment what still happens which leads to what and causes what? | back 114 the body will attempt to still produce the functional outcome
desired |
front 115 Lack of balance between certain types of muscles | back 115 Muscle Imbalance |
front 116 Certain muscles are prone to _______ Muscle imbalance is often dictated by what? | back 116 tightness weakness common posture abnormalities |
front 117 The combination of tightness and inhibition of a muscle can lead to altered ________? It can result in alteration in _______ of joints leading to ______? | back 117 movement patterns biomechanics degeneration |
front 118 Muscle Imbalance alters what 3 things? | back 118 Alters the Length-Tension relationship of muscles |
front 119 Average steps per day? | back 119 5,000-10,000 1-1.5 2 – 3 |
front 120 Look at power, speed, agility, performance, quickness for athlete (above water line)…but now also look at functional movement such as stability mobility and quality of movement (below water line | back 120 iceberg effect |
front 121 The act or power of moving from place to place by means of one’s own mechanisms or power | back 121 LOCOMOTION |
front 122 4 quantitative domains of locomotion? | back 122 Temporal |
front 123 phases (stance/swing) and events (foot-strike, toe-off), stride rate | back 123 Temporal domain of locomotion |
front 124 muscle activation patterns | back 124 Electromyography domain of locomotion |
front 125 stride length, velocity, ranges of motion, acceleration | back 125 Kinematic domain of locomotion |
front 126 ground reaction forces, pressure patterns, joint forces, moments of force, work, energy and power | back 126 Kinetic domain of locomotion |
front 127 Alternating action of the two lower extremities | back 127 WALKING |
front 128 Translatory motion of the body brought about by rotary motion of some of its parts | back 128 WALKING |
front 129 Two Phases of walking? | back 129 Swing |
front 130 Reference limb in contact with the floor | back 130 stance phase |
front 131 Reference limb not in contact with the floor | back 131 swing phase |
front 132 Two components of Gait? only one foot in contact with the
floor? | back 132 Phase and Support (1) Single Support: (2) Double Support: |
front 133 the stance phase is ___% of the gait cycle? 5 movements of walking? | back 133 60% initial contact, loading response, midstance, late midstance, propulsion |
front 134 What is one full lower extremity cycle? | back 134 One stride |
front 135 from heel strike to the next heel strike of the same leg | back 135 Stride |
front 136 distance covered in one stride | back 136 Stride length |
front 137 from heel strike of one leg to heel strike of opposite leg | back 137 Step |
front 138 (IFD)...this equals the? What is it? AKA? | back 138 Interfoot Distance walking base Side-to-side distance between the line of the two feet Also known as ‘stride width’ |
front 139 Stance vs. Swing: Single vs. Double support: | back 139 60% 40% 40% 20% |
front 140 What is the highest point during walking normally? Lowest point? | back 140 midstance double leg support |
front 141 Name a few things you can analyze during walking? | back 141 arms, spine, hips, ankle etc... |
front 142 During the gait cycle: | back 142 the legs each other trunk thoracic spine pelvis lateral tilt 5 pelvis |
front 143 Initial Contact: Hip has ___ degree flexion knee has ____ degree flexion Ankle is? | back 143 30 5 neutral |
front 144 what happens during loading phase to hip knee and ankle? | back 144 hip stays at 30 flexion, knee begins at 5 degree flexion then ends at 20 degrees flexion, ankle is neutral to plantar flexion and back to neutral |
front 145 what happens during mid stance phase to hip knee and ankle? | back 145 hip is extending and knee is extending and ankle is dorsiflexed |
front 146 what happens during terminal phase to hip knee and ankle? | back 146 hip is extended beyond neutral knee is extended and then flexes ankle dorsiflexes then plantar flexes at end |
front 147 what happens during pre swing phase to hip knee and ankle? | back 147 hip is flexing and then knee is rapid flexing and ankle is rapid plantarflexion |
front 148 what happens during initial swing phase to hip knee and ankle? | back 148 hip is rapid flexion knee-mostly flexes, then reverses and extends at the end of phase ankle dorsiflexes |
front 149 what happens during mid swing phase to hip knee and ankle? | back 149 hip flexes knee has rapid extension ankle dorsiflexes to neutral |
front 150 what happens during swing phase to hip knee and ankle? | back 150 hip -slight extension knee- extends throughout but reverses and flexes slightly at end ankle - remains neutral |
front 151 | back 151 mid swing phase |
front 152 | back 152 Swing phase |
front 153 | back 153 Initial swing phase |
front 154 | back 154 Pre swing phase |
front 155 | back 155 Terminal phase |
front 156 | back 156 Mid stance phase |
front 157 | back 157 Loading phase |
front 158 | back 158 Initial contact phase |
front 159 Unnecessary ______ movements decrease gait economy...give three examples? | back 159 lateral a. Excessive trunk rotation |
front 160 What should you have at the joints during walking? Tendons of two _______ of lower extremity contribute to economy of muscular action in walking | back 160 Normal flexibility joint muscles |
front 161 Properly functioning _______ contribute to a well coordinated, efficient gait? What can interfere with this? | back 161 reflexes Injury, disease, or substance abuse can interfere with the walking reflex |
front 162 The swing phase is more ________ than pendular and is longer than ______ phase (for running) | back 162 muscular support |
front 163 Walking variations up stairs or on a ramp? During the swing phase what is exaggerated? | back 163 Forward lean of body to direct the push of legs through the body’s center of gravity Swing phase is an exaggerated knee lift and dorsiflexion of the ankle |
front 164 Walking variations down stairs or down a ramp? What is different about the swing phase? | back 164 Eccentric contraction of muscles to lower body at a controlled rate, and maintain line of gravity toward the back of the base of support swing phase has a slight lifting of rear foot to clear the step |
front 165 2 Differences from walking and running? | back 165 there is no double support phase for running and |
front 166 Two major types of running? | back 166 Races |
front 167 Concerned with change of direction, pace, and stability (type of running) | back 167 Games and Sports |
front 168 Concerns are time and distance (type of running) | back 168 Races |
front 169 The difference in joint actions between walking and running are a matter of ________ and ________? Essentially the same action, but the _____ is generally larger in running? Differences also exist in __________? | back 169 degree and coordination ROM Ground Reaction Forces (GRF) |
front 170 Describe the graph of ground reaction forces for walking vs. running? | back 170 vertical force is body weight (y axis) and time is axis. The first peak for running is the heel strike...then the dips indicates the loading response which is an eccentric muscle action. For walking, the heel strike and loading response isn't very noticeable. |
front 171 The swing phase is more ________ than pendular and is longer than ______ phase | back 171 muscular support |
front 172 Initial foot contact: | back 172 - ball of foot - heel or whole foot |
front 173 During running, the flexed leg brings the mass of the leg ________? What does this reduce and increase? | back 173 close to the hip reducing inertia and increasing angular velocity |
front 174 Who produces an overall greater force in newtons for ground reaction forces during running? Mid-foot or heel striker? | back 174 Heel striker (uses a heel to toe foot pattern) |
front 175 There are two factors that impact the inertia of a rotating body, what are they? | back 175 The mass of the body/object |
front 176 During the support phase in running, the knee and ankle “give” in
____, then _______ as the body passes over the foot? | back 176 flexion extend speed vigorous |
front 177 For running, speed is governed by _______ and _____of stride | back 177 length and frequency |
front 178 determined by length of leg, ROM of hip, and power of leg extensors | back 178 Length of Stride |
front 179 During running, the body becomes a projectile and depends
on.... | back 179 take off projection center of gravity |
front 180 determined by speed of contraction and skill of performer | back 180 Stride rate |
front 181 Sprint form of running is usually aimed at what three respective technique variants? | back 181 drive, stride and lift |
front 182 During running this is emphasized during the start and acceleration phases? These 2 are both emphasized during the maximum speed phase? | back 182 drive stride and lift |
front 183 Starting acceleration and push-off action (first 22-33 yd) | back 183 Drive |
front 184 During the drive of sprinting you want: _____ thrust with body _____ with a ____ trunk | back 184 Horizontal low piked |
front 185 What are 2 techniques to use during a sprint? | back 185 Powerful arm action through greater range than stride technique Full-range driving action with exaggerated knee lift |
front 186 What does the crouch start enables the runner to do? | back 186 exert maximum horizontal force at take off, providing maximum acceleration against inertia |
front 187 Full-flight striking or pushing action (after 33 yd) | back 187 Stride |
front 188 What type of posture do you want during a stride during a sprint? What type of movement do you want? | back 188 “Running Tall” posture, smooth & continuous movement |
front 189 Forward swing to shoulder height, backward swing to the hip | back 189 Full-range arm action |
front 190 Kick-at-speed pulling action | back 190 Lift |
front 191 What type of posture do you want during lift during a sprint? What do you want in the knees? Arms? What do you want to be light? | back 191 running tall posture Rapid knee lift Full-range arm action, increased emphasis on rapid pumping or beating Lighter striking/clawing action |
front 192 Errors in walking + running can be visible in one location but be caused by ______ in another location? Can they occur in both running and walking? | back 192 dysfunction Yes, one of the 2 or both..depends on person |
front 193 Trendelenberg gait...this is usually what? If it is bilateral its called what? What are 4 common causes? | back 193 Lateral Trunk bending Usually unilateral |
front 194 | back 194 Lateral trunk bending |
front 195 Overpronation Gait abnormalities can be due to weak _______ muscles? What are some examples? What muscles would be tight? Overpronation could also mean what? | back 195 inverter/supination Tibialis Anterior Gastrocnemius problems at hip or knee such as knee valgus |
front 196 Knee valgus could mean what is weak? | back 196 Weak gluteus max & medius |
front 197 COMMON GAIT ABNORMALITIES: Functional Leg-Length Discrepancy....describe what this could be? | back 197 Swing leg: longer than stance leg |
front 198 4 compensations for swing leg being longer than the stance leg? | back 198 A. Circumduction…longer leg has to swing around in order to clear it
from ground |
front 199 Normal walking base in cm? If you have an increased walking base what could be 2 causes? Could also be due to? | back 199 5-10 cm abducted hip or valgus knee instability |
front 200 In stance phase (Heel contact – Foot flat) What happens in the swing phase if your foot isnt dorsiflexed? Could be due to weak ____ or spastic ______? | back 200 Foot slap toe drag Weak Tibialis Ant. |
front 201 Postural analysis views? | back 201 anterior, posterior, lateral and skyline |
front 202 Posture guidelines for head, shoulders, hips, knees and feet? | back 202 head- neutral, ear in line with center of shoulder shoulders-neutral, center of shoulder should be in line with center of hip hips-neutral spine with abdominals drawn in knees-straight feet- pointing straight with neutral position at ankle |
front 203 what 2 things should you add in to a picture to evaluate posture? | back 203 plumb line and posture grid |
front 204 good posture: “a state of ______ and _______ balance, which protects the supporting structures of the body against injury or progressive deformity” “Good posture is present when the ______ passes through the center of each joint just anterior to the midline of the knee, through the greater trochanter, bodies of the lumbar vertebrae, shoulder joint, bodies of the cervical vertebrae, and the lobe of the ear, placing the body in equilibrium and resulting in all internal forces equaling _____” (Kritz & Cronin, 2008) | back 204 muscular and skeletal line of gravity zero |
front 205 Name what this is and whats going on with the body? Name some short and tight muscles? Lengthened and weak ones? | back 205 Kyphosis-lordosis forward head, inc cervical lordosis, inc thoracic kyphosis, inc lumbar lordisis, ant. ppelvic tilt short-neck extensors lengthened- neck flexors |
front 206 Name what this is and whats going on with the body? Name some short and tight muscles? Lengthened and weak ones? | back 206 Sway back forward head, inc cervical lordosis, inc thoracic kyphosis, dec lumbar lordosis short- upper abdominals lengthened- lower abdominals |
front 207 Name what this is and whats going on with the body? Name some short and tight muscles? Lengthened and weak ones? | back 207 flat back forward head, inc cervical lordosis, dec thoracic kyphosis, dec lumbar lordosis, post. pelvic tilt short- neck extensors |
front 208 Name what this is and whats going on with the body? Name some short and tight muscles? Lengthened and weak ones? | back 208 Military type normal cervical spine, normal thoracic kyphosis, inc lumbar lordosis, ant. pelvic tilt short- lumbar extensors |
front 209 Janda’s Compensatory Patterns 3 syndromes? | back 209 Upper Cross Syndrome |
front 210 Describe it? | back 210 Upper cross syndrome rounded shoulders forward head posture |
front 211 Describe it? | back 211 Lower crossed syndrome Increase lumbar lordosis |
front 212 Results in Rib external rotation | back 212 Spinal Extension |
front 213 | back 213 Pronation Distortion Syndrome |
front 214 Excessive foot pronation (flat feet) | back 214 Pronation Distortion Syndrome |
front 215 Describe normal Position for scapula ? | back 215 Between T2 – T7 |
front 216 Common Issues to look for in scapula If your _______ is in a poor resting alignment, your scapulae will never be in the right position. | back 216 Winged *** thoracic spine |
front 217 A protrusion of the inferior angle of the scapula | back 217 Winged Scapula |
front 218 Issues associated with winged scapulae: | back 218 flexion serratus anterior or lower traps Pec Minor |
front 219 The shoulders are pulled forward The subscapularis and Pectoralis minor and clavicular &
sternal heads of the pectoralis major muscles may be _______ | back 219 Protracted Scapula short The trapezius (middle fibers) and particularly the rhomboids |
front 220 Shortened/strong rhomboids – middle trap...where is this seen in? | back 220 Retracted Scapula military stance posture |
front 221 Upper traps, Levator Scap. are short/tight/active With this you may see differences where? | back 221 Elevated Scapula left and right sides |
front 222 What could a trunk tilt crease mean? | back 222 one side sags lower |
front 223 what happens to lumbar spine if pelvis raised on right? on left? | back 223 right- flexed to the right and concave to right left- flexed to left and concave on left |
front 224 what happens to lumbar muscles if pelvis raised on right? on left? | back 224 right- shortened right quadratus lumborum and right lumbar erector spinae left- shortened left quadratus lumborum and left lumbar erector spinae |
front 225 what happens to the hip joint if pelvis raised on right? on left? | back 225 right- right hip is adducted and left hip is abducted left- left hip is adducted and right hip is abducted |
front 226 what happens to the muscles of the hip if pelvis raised on right? on left? | back 226 right- shortening of right hip adductors and left hip abductors and imbalance between right and left hamstrings left- shortening of left hip adductors and right hip abductors and imbalance between right and left hamstrings |
front 227 How does aging affect posture? inactivity? Poor postural habits? Biomechanical compensation? Body comp? Workplace? Injury? | back 227 your body gradually loses its capacity to absorb and transfer forces leads to loss of natural movement flow, eventually becomes your structure muscle imbalance, adaptive shortening, muscle weakness & instability within the “core”, increases load, stresses on spinal structure, leads to spinal deviation, curved shoulders leads to reduced loading capacity or elasticity. |
front 228 Posture is the single most common cause of painful ______ syndromes affecting the body | back 228 soft tissue |
front 229 tech neck can give you what? | back 229 bad posture, curved shoulders |
front 230 Optimizing muscle balance and posture will help reduce the likelihood of ___________ | back 230 dysfunction |
front 231 Joint by joint approach: (stability or mobility?) foot, ankle, knee, hip, lumbar spine, thoracic spine, scapula, elbow? | back 231 stab mob stab mob stab mob stab stab |
front 232 mechanisms of locomotion: at heel strike what is going on with the ankle? During eccentric/loading? | back 232 Supinated and locked ankle Unlocks - moves into pronation (ankle dorsiflexion and rear foot eversion) |
front 233 What are these things describing? Impact forces to be attenuated over a longer period Essentially this is a _______? | back 233 foot pronation protective mechanism |
front 234 what happens to ankle during heel lift off? | back 234 Move back toward supination to allow toes create rigid lever to propel runner |
front 235 what are two primary stabilizing muscles of ankle? They function to: | back 235 Tibialis Posterior torsion rear foot eversion medial longitudinal arch |
front 236 3 things that levers Possess? | back 236 Fulcrum/axis |
front 237 Lever arm consists of? | back 237 Effort arm |
front 238 If the effort & resistance are applied at some other | back 238 perpendicular resistance line to the fulcrum |
front 239 rigid bar that can rotate about a fixed point | back 239 Lever |
front 240 3 things that Levers Possess? | back 240 Fulcrum/axis |
front 241 Bones act as a ______, joints as the _______, muscles as a form of ______, and external forces as the __________? __________ occurs as a result of coordination of levers to produce maximum force? | back 241 lever fulcrum effort resistance forces movement |
front 242 portion of lever between fulcrum and the force points | back 242 Lever arm |
front 243 distance between fulcrum and pt of effort | back 243 Effort arm |
front 244 distance between fulcrum and res. Pt. | back 244 Resistance arm |
front 245 If the effort & resistance are applied at some other angle than
90° then the: | back 245 perpendicular fulcrum |
front 246 Levers serve 2 important functions, what are they? What can both do depending on the type of lever? | back 246 1. Overcome a resistance larger than the magnitude of the effort…little effort to overcome a large work load (wheel barrow)…..2. increase the speed and ROM through which a resistance can be moved….both will vary depending on type of lever |
front 247 ability of a lever to magnify force | back 247 Mechanical Advantage |
front 248 Ratio between effort applied to the lever and the resistance overcome by the lever | back 248 Mechanical Advantage |
front 249 2 equations for mechanical advantage? Explain them both a little | back 249 Mechanical Advantage = R / E (greater the resistance and smaller
the effort…the greater the mechanical advantage) or |
front 250 Levers outside the body | back 250 External Levers |
front 251 External Levers: Aid in _________ | back 251 daily activities resistance range of motion and speed of movement (bat, golf club) |
front 252 Levers found within the body | back 252 Anatomical Levers |
front 253 What makes up Anatomical Levers? | back 253 bones, joints, and muscles |
front 254 Muscles can serve as the ___ or ________ force? Going down on a pull up (dealing with levers), the muscles are the _______ force and _____ is the effort force? | back 254 effort or resisting force depending on action resistance force gravity |
front 255 ________ and _______ of the effort & resisting forces can alter the classification of lever system | back 255 Location source |
front 256 Typically, in anatomical levers, what is the effort force and resistance force? | back 256 muscle insertion is the effort/force |
front 257 Classification of Levers vary in what? Name the 3 types? | back 257 arrangement of axis, effort and res. arm 1. First Class Levers |
front 258 Fulcrum lies between the effort and the resistance…in middle | back 258 First Class Levers |
front 259 2 functions of what lever system? 1. Magnify the effects of the effort 2. Increase speed & ROM | back 259 1st class |
front 260 Examples of what lever system? | back 260 1st class |
front 261 going from distance of resistance to axis = ? | back 261 res. Arm |
front 262 distance from effort to axis= ? | back 262 effort arm |
front 263 For 1st class levers, how do we increase mechanical advantage? How do we increase speed and ROM? | back 263 greater mechanical advantage if we inc effort arm and dec resistance arm…if we do opposite it will increase speed and ROM |
front 264 Describe 1st class lever system with a skull? (what is the resistance and effort?) | back 264 skull has gravity as resistance and muscles near occipital bone as effort that keep head up |
front 265 Resistance lies between the fulcrum & effort | back 265 Second Class Levers |
front 266 For 2nd class levers, the effort Arm is always ______ than the
| back 266 longer Allows for less effort to move a resistance…large mechanical advantage ROM |
front 267 2 examples of a 2nd class lever system? Explain what the axis, res. and effort are? | back 267 Wheelbarrow or a calf raise…toes=axis, resistance=COG of body, effort= muscle that is shortening and pulling upward |
front 268 Effort lies between the axis and the resistance | back 268 Third Class Levers |
front 269 For 3rd class levers, what is the relationship between res. arm and effort arm? What does this mean? What is the advantage? This is the most common what? | back 269 RA is always longer than EA Takes more effort to overcome a resistance Advantage is increased speed & ROM anatomical lever |
front 270 The same system can vary in its _______________ depending on the action of the system and which forces are acting to resist and which are acting as an effort force | back 270 classification of the type of lever |
front 271 lowering the arm is _______ and raising it is __________? Lowering is what type of lever, why? What about when raising, why? | back 271 eccentric concentric 2nd because Axis = Elbow Joint 3rd class because Axis = Elbow Joint |
front 272 Formula for levers? Need to know ____ of the 4 values? A lever whose
EA is longest favors ______? | back 272 Effort x Effort Arm = Res. x Res. Arm just 3 force generation speed and distance |
front 273 Levers of the human body typically have longer and short what, why? | back 273 Most have longer RA compared to EA…the EA is short on body because
the muscles are close to joint attachment (axis) |
front 274 Anatomical levers favor what? | back 274 speed and ROM |
front 275 Desire Speed & Distance = _______ levers | back 275 Longer Shorter |
front 276 Longer levers require more ______ to move them | back 276 force |
front 277 In Lacrosse, a defensive/longer stick does what to the ball? what does it need more of? What does the offensive/shorter stick have? | back 277 can throw it further but need more force higher angular velocity |
front 278 Longer levers enhance______ and _____?This is detrimental when __________ is needed? Give an example? | back 278 linear velocity & ROM high angular velocity Example: Swinging at a fast ball (choke-up to decrease length of bat & increase angular vel.) |
front 279 Shorter levers may Compromise ______ and ______? | back 279 Linear velocity & ROM |
front 280 A-R-F F-A-R A-F-R | back 280 2nd class lever 1st class 3rd class |
front 281 for 1st class levers, do the RA and FA move in the same or opposite directions? 2nd class? 3rd class? | back 281 opposite same same |
front 282 Defined as the turning effect produced by a force | back 282 Torque |
front 283 Causes change in angular motion | back 283 Torque |
front 284 Movements of limbs at joints are controlled by torques produced by ___________? | back 284 the muscles |
front 285 Torque produced by a force may be called a _________ or __________? | back 285 Moment of Force or Moment |
front 286 When an external force is directed through the center of gravity of an unrestrained system, it causes that system or object to move in a linear path | back 286 Centric Force |
front 287 When an external force is not directed through the center of gravity of an unrestrained system, it causes that system or object to move in a linear and angular path | back 287 Eccentric Force |
front 288 Forces acting on an object in opposite directions and not directed through the center of gravity...what will the object do? Effects only _____? | back 288 Force Couple object will merely rotate angular motion of the object |
front 289 In a force couple, If both forces are equal, then what happens? | back 289 the resultant of the two forces is 0, as no change in linear motion occurs |
front 290 a rotary force | back 290 torque |
front 291 Name a few anatomical force couples? | back 291 internal oblique pulling in towards center and external oblique pulling outwards also, upper trap pulling up and lower trap pulling down also muscles that cause anterior and posterior pelvic tilt |
front 292 Rotary force generated by the muscles acting on bone crossing a joint | back 292 Internal Torque |
front 293 There can be muscles acting to cause rotary motion in a given
direction and those that resist motion by causing what? | back 293 torque forces in the opposite direction joint stabilization |
front 294 Rotary forces generated by external loads acting on the body | back 294 External torque |
front 295 The body works to balance, resist, or overcome external ________? | back 295 torques |
front 296 Name a few different names for internal torque? | back 296 moment of effort, effort moment, effort torque |
front 297 Name a few different names for external torque? Give 2 examples of external torque? | back 297 moment of load, resistance torque, resistance moment gravity holding a dumbbell |
front 298 Torque is influenced by the _________ and _______ of the line of action of the force as well as by its _____? | back 298 position and orientation size |
front 299 Torque is produced by? | back 299 magnitude of the force and the distance from the axis of rotation that the force is applied |
front 300 Torque is a ______ quantity, because the turning effect is around a specific axis that is directed in a specific direction | back 300 vector |
front 301 is a quantity that has both magnitude and direction? Represented by
__________? | back 301 Vectors arrow shaped symbols size |
front 302 A vector symbol’s orientation on paper represents ______ and its length represents ___________? | back 302 direction magnitude |
front 303 Counterclockwise Torques are ______ | back 303 Positive (+) Negative (-) |
front 304 Torques that act about the same axis may be ________ or ____________? | back 304 added or subtracted |
front 305 The distance between the line of action of the force and the axis of rotation is called the ? The greater this distance, the greater the ________ produced by the force | back 305 Moment Arm torque |
front 306 Can also be referred to as the Force Arm, Lever Arm, or Torque Arm | back 306 Moment Arm |
front 307 the shortest distance from the axis of rotation to the line of action of the force. The shortest distance is always the length of the line that is _________ to the force’s line of action (d⊥) | back 307 The force arm perpendicular ⊥ (90°) |
front 308 If the system is restricted to moving around an axis, the body rotates when the force is applied but only if the force does not act ______________? | back 308 directly through the axis of rotation |
front 309 The point of application of the force must not be at the _____ and the line of action of the force must not pass ____________? | back 309 axis through the axis |
front 310 To open (rotate) a door, the force is applied where? | back 310 at a point far from the hinges |
front 311 If the line of force is going directly through the axis of rotation you can’t cause something to rotate…will only push it in what way? | back 311 in a linear way |
front 312 Torque is produced by muscles when they pull on ______? The result is ? The stronger the contraction of a muscle, the greater the ? The longer the force arm, the greater the ? | back 312 bones rotary motion of the body segments torque on the bone torque |
front 313 Just look at picture | back 313 look at picture |
front 314 The greater the _________….the greater the torque | back 314 moment arm could recruit more muscles |
front 315 The point of application of a muscle’s force on a bone (insertion point) cannot be changed, but what can? what is it in line with and how does it change? As a result of the changing direction of muscle force on the bone as the bone rotates, what happens to the force arm? Therefore, the torque that a muscle is able to exert on a bony segment changes as the ______? | back 315 the line of action of a muscle’s pull (in line with the direction of the muscle’s shortening) changes relative to the bone (the angle of muscle’s insertion) the force arm changes length segment position changes |
front 316 Moment arm is biggest at what position on muscles and bone? What does this mean? What happens to it through ROM? | back 316 90 (means we can generate the most force here)….will change slightly during a range of motion |
front 317 Why do you need to keep the dead lift bar close to you? | back 317 Bar needs to stay close to you during a dead lift or else if it is far away you will inc torque |
front 318 The amount of torque acting to rotate a system is found by multiplying the ______ of the applied force by the ____________ from the line of force to the axis of rotation? Units for each? | back 318 magnitude force arm distance T = Torque |
front 319 If a force of 50N were applied with a force arm of 2m, the torque produced by that force would be ? If the weight is lighter, what happens? Show this? If the weight is placed closer to the axis what happens? (same original force) Show this? | back 319 100 N-m, or 100 torque units it creates less torque it creates less torque |
front 320 If the line of force of the weight is directed through the axis itself, what happens? | back 320 zero distance (d⊥) results, therefore zero torque and no rotation is
produced. |
front 321 Determine the Torque given the following: 400 N and 4 m? | back 321 1600 N-m |
front 322 what is the unknown force? FA = 15cm RA = 5cm R = 400 | back 322 Set them equal to each other 400 x 00.5= 20 Nm 20 Nm= _____ x o.15 Force= 133 |
front 323 RA = 20cm R = 2000 N | back 323 2000 x .2= ______ x .5 |
front 324 RA = 15cm R = 2000 N | back 324 2000 x .15= ____ x .25 |
front 325 Often, we purposely increase __________ in order to increase torque so that we can more easily move a relatively large resistance (increasing our leverage) | back 325 force arm length |
front 326 distance between the axis and the point of resistance application | back 326 Resistance arm |
front 327 There is a _______ relationship between length of the two lever arms. Give examples? | back 327 Inverse Between force & force arm |
front 328 The longer the force arm, the _____ force required to move the lever if the resistance & resistance arm remain constant. Shortening the resistance arm allows a ______ resistance to be moved if force & force arm remain constant | back 328 less greater |
front 329 __________ relationship between force components & resistance components. If either of the resistance components increase, what would happen? | back 329 Proportional there must be an increase in one or both of force components |
front 330 Greater resistance or resistance arm requires what? Greater force or force arm allows for what? | back 330 greater force or longer force arm a greater amount of resistance to be moved or a longer resistance arm to be used |
front 331 Human leverage system is built for _________ and ________ at expense of force? | back 331 speed & range of movement |
front 332 Short force arms & long resistance arms require great _______ to produce movement? | back 332 muscular strength |
front 333 Human leverage for sport skills requires several _______? Give an example? | back 333 levers throwing a ball involves levers at shoulder, elbow, & wrist joints |
front 334 The longer the lever, the more effective it is in imparting ______? Give an example? | back 334 velocity A tennis player can hit a tennis ball harder with a straight-arm drive than with a bent elbow because the lever (including the racket) is longer & moves at a faster speed |
front 335 Long levers produce more _________ and thus better performance in some sports such as baseball, hockey, golf, field hockey, etc. Explain the 2 points in the picture? | back 335 linear force First point doesn’t move as far…distance gets greater as you move away from axis of rotation…means that 2nd point is moving faster because it gets further in the same amount of time |
front 336 For quickness, it is desirable to have a short _________? Describe this with a baseball catcher throwing on the field? What does this increase? | back 336 lever arm baseball catcher brings his hand back to his ear to secure a quick throw…inc angular velocity |
front 337 Tension in the muscles crossing a joint does not always promote what? | back 337 the joint’s stability |
front 338 Only the component of muscle force acting ____________ to the long axis of the attached bone actually contributes to the rotation of a body segment around the joint crossed by the muscle | back 338 perpendicular |
front 339 There exists both _________ and ________ forces created by muscle activation | back 339 linear (non-rotary) and torque (rotary) |
front 340 The angle of pull of most muscles in the resting position is ? | back 340 less than 90 degrees |
front 341 Less than 90 degrees (angle that we start off in pulling), nonrotary component force is directed ______ joint. Name of force? | back 341 toward (compressive or stabilizing force) |
front 342 If angle of pull exceeds 90 degrees then the nonrotary component force is directed ______ from the joint. Name of force? | back 342 away (distensive or dislocating force) |
front 343 When you think about human movement and muscle attachments it is rare that the angle of pull is ? Thus – typically the muscle is generating either a ______ or _____ force in addition to rotary force | back 343 at 90 degrees. When it is, it is for a brief moment stabilizing or distensive |
front 344 name each picture | back 344 1st= stabilizing force 2nd= right at 90 3rd= dislocating force |
front 345 Because we want to maximize the application of force to generate rotary motion we rely on the body’s structure to increase our ____________? Name one way we do this? | back 345 mechanical advantage One way we do this is through the utilization of pulleys |
front 346 changes the direction of the force, making it easier to lift things | back 346 A pulley |
front 347 When the direction of pull of a muscle is altered, the bone or bony prominence causing the deflection | back 347 Anatomical Pulleys |
front 348 The function of any pulley is to? What is this in humans? | back 348 redirect a force to make a task easier. The “task” in human movement is to rotate a body segment. |
front 349 Anatomic pulleys (in the majority of instances) make this task easier by deflecting the action line of the muscle _____ from the joint axis, thus increasing the ____________. By increasing this, a force of the same magnitude (with no extra energy expenditure) produces greater _____? | back 349 away MA of the muscle force torque |
front 350 describe pulleys with tendons? | back 350 Tendons wrap around certain bones to essentially create a pulley and inc moment arm length |
front 351 Act to increase the angle of pull so that it increases the rotary component of force. What does this also increase and allow for? an example of this on the body? | back 351 Anatomical Pulley It increases the moment arm which allows for more force to be generated patella |
front 352 Rotation =? | back 352 - Torque – Linear motion |
front 353 Rotational Component of Magnitude formula? What does this tell us and not tell us? | back 353 Fp (original force) = Fm (sin α) (sin of angle of pull) This only tells us what portion of the force is generating rotary
motion |
front 354 Non-Rotational Component of Magnitude formula? | back 354 Fp (proportion of original force) = Fm (force mag) (cosα) |
front 355 Do we do sin or cos if angle is at 90, why? | back 355 For linear movement |
front 356 How much torque is produced at the elbow by the biceps brachii
inserting at an angle of 60° on the radius when the tension in the
muscle is 400 N? | back 356 Fp = Fm (sin α) |
front 357 what do you assume if they give you no angle to the rotational component? What if they give you an angle? | back 357 If no angle is given to effect the rotational component of a force magnitude then that force magnitude is the rotational component and thereby the overall Force (Force Magnitude) x (sin α) = Rotational Component |
front 358 How much force must be produced by the biceps brachii attaching at
90° to the radius at 3 cm from the center of rotation at the elbow
joint, to support a weight of 70 N held in the hand at a distance of
30 cm from the elbow joint? | back 358 Since sin 90° = 1 it is not a factor in these calculations Convert centimeters to meters by dividing by 100 |
front 359 The quadriceps tendon attaches to the tibia at a 30° angle 4 cm from the joint center at the knee. When an 80 N weight is attached to the ankle 28 cm from the knee joint, how much force is required of the quadriceps to maintain the leg in a horizontal position? | back 359 ankle force= Its negative because its clockwise which is negative (at
ankle…force going down) sin(30) x original force= new force 0.04 m=distance 80 x 0.28=torque....= 22.4 22.4= force x 0.04 force=560 sin(30) x original force= 560 original force = 1120 N |
front 360 Use Non-Rotational Components to determine what? Name 2 types and if they are positive or negative? | back 360 Joint Reaction: Distensive or Compressive Reminder: we will record Compressive forces as (-) and Distensive forces as (+) |
front 361 The biceps brachii on the lower arm during an isometric contraction
while holding a 70 N dumbbell. LOOK AT PIC ON PHONE | back 361 Sum compressive forces (neg) and determine the resulting distensive forces for joint to be stable Cos=non rotational component…has nothing to do with torque piece do that at very end F=1496 and distensive forces= 16.5 |
front 362 What do you do with 2 forces acting against the muscular force ? | back 362 …add them together |
front 363 Distensive = what angle? Stabilizing= ? | back 363 Greater than 90 less than 90 |
front 364 In this image, do the lengths of the resistance arm and effort arm change? What type of lever is this? | back 364 yes Third class…most concentric actions |
front 365 If the point of muscle attachment is 2cm from the elbow joint, and the 44N dumbbell is 20 cm from the elbow how much muscle force must be developed to raise the dumbbell? | back 365 440 N + |
front 366 How does arm length impact this? | back 366 The body weight increases the amount of resistance force |
front 367 Application to Sports When you desire_______ on a ball you apply an ______ force (torque) | back 367 rotation (spin) eccentric |
front 368 Describe how this picture is beneficial? | back 368 Increases moment arm which increases torque because its farther away from their pivot point…start low and hit high |
front 369 Power output relative to crank length? What happens if crank length gets too large? | back 369 As crank length gets larger….larger moment arm which increases power
output |
front 370 Understanding torque is important for having a better knowledge about the mechanics of various __________? | back 370 exercises |
front 371 How to compare exercises | back 371 Torque and Exercise |
front 372 When is external torque greatest during deadlifting? Why? | back 372 1……barbell is furthest from hips here which increases moment arm length |
front 373 During a Deadlift A lifter with longer arms will have a greater _______ than a lifter with short arms. Describe how lifters with shorter arms struggle? | back 373 femur force arm length initial mechanical advantage The lifter with short arms must drop their hips lower, increasing the external moment arm and thus a greater torque must be generated to lift the bar. |
front 374 what does this do to the back? | back 374 This hip extension puts a lot of external load on the back |
front 375 Front vs Back Squat Assuming the load is the same, in which position is torque produced
by the bar greatest on the low back? | back 375 Last pic has greatest external torque bc you lean forward the most with back squatting which increases moment arm length |
front 376 What type of lever is this? | back 376 Pivot at feet, resistance in middle and force up above |
front 377 Weight force = 25 N | back 377 -3.46 torque res Muscle force= 103.75 (4.15= force x 0.04) just have one be positive and the other negative...as long as they oppose each other i pointing inn different directions |