Applied Kinesiology PDF

Optimal performance of movement requires that the body's muscles work together to produce force while simultaneously stabilizing the joints. Typically, people who have weaker stabilizer muscles (eg. deep abdominals, hip stabilizers, scapula retractors) exhibit problems with performing proper, effici...

Optimal performance of movement requires that the body's muscles work together to produce force while simultaneously stabilizing the joints. Typically, people who have weaker stabilizer muscles (eg. deep abdominals, hip stabilizers, scapula retractors) exhibit problems with performing proper, efficient movement, which may lead to pain and/ or injury. Therefore, functional training (or purposeful training) that takes advantage of closed kinetic chain activity and focuses on body's stabilizing musculature is often incorporated into rehabilitation and/ or post rehabilitation programs for these individuals. In a closed- chain kinetic movement, the end of the chain farthest from the body is fixed on the ground such as the squat where the feet are fixed and the rest of the leg chain (i.e ankle, knees, hips) moves. In an open- chain exercise, the end of the chain farthest from the body is free, such as a seated leg extension. Closed- chain exercises tend to emphasize compression of joints, whereas open-chain exercises tend to involve more shearing forces at the joints. Furthermore, closed-chain exercises involve more muscles and joints than open-chain exercises, which leads to better neuromuscular coordination and overall stability at the joints. An example of a program that develops functional strength and range of motion is a conditioning routine that incorporates 5 primary movements patterns of ADL (activities of daily living) Bending and lifting (squats), Single leg movements (lunges), pushing, pulling, rotation. ***"Squats and Lunges: Is "Never let the knees go past the toes" an appropriate movement cue?*** *While it is appropriate to avoid excessive forward movement of the knee during squatting and lunging movements, it is a myth that exercisers should never let the knees go past the toes during a lunge or a squat.* *In 2003, researchers confirmed that knee stress increased by 28% when the knees were allowed to move past the toes while performing a squat. However, hip stress increased by nearly 1000% when forward movement of the knee was restricted. In addition, in group exercises, the above cue has long been an effective general rule when trying to teach an exercise to a room full of people with different skill levels, abilities and goals.* *The general pointer while performing a lunge is to try to keep the knees aligned over the second toe so that the knee is moving in the same direction as the ankle joint. However, in reality, exercisers often find the knee translating forward to the toes or beyond in a squat or lunge movement, so there are other things that must be considered, specifically limb length.* *During lunge or squat movements, fitness professionals should always emphasize beginning the movement, by pushing the hips backwards before lowering towards the floor (an action referred to as "hip hinging"). This technique prevents premature forward movement of the knee by shifting the hips backward. As the exerciser continues to lower his or her body downward, this creates a healthy hinge effect at the knee, but there comes a time where the knee (tibia) will begin to move forward in order to maintain balance. If an exerciser happens to have long limbs, then it is realistic to expect the knees to move forward over or beyond the toes. Any attempt to prevent this motion will result in either the individual falling backwards or bad squat or bad lunge technique that places increased loads on the low back. As long as fitness professionals teach the lunge/ squat movement correctly by first initiating the movement at the hips and avoid premature forward movement of the knees, then the fact that the knees are moving forward is quite safe.* Posture and Neutral Spine: The spine of a fully grown healthy adult has 24 movable vertebrae and 3 normal curves, the cervical and lumbar regions are naturally convex anteriorly and concave posteriorly, referred to as Lordotic curvature. In contrast, the thoracic region is concave anteriorly and convex posteriorly know as Kyphotic curve. Fitness professionals can promote good posture and muscular balance by having clients and class participants perform all activities with as close to a neutral spine alignment as possible. Effective cueing and correction techniques, combined with verbal and visual feedback, will help people become more aware of their posture. Good posture is a neuromuscular skill that can be achieved through repetition and practice. The position of the pelvis plays a major role in the determination of the forces applied at the lumbar spine. If the lumbar spine is correctly aligned with regard to the pelvis, and the pelvis is properly balanced in relation to the legs, the forces applied to the lower back can be reduced. Achieving this balance requires excellent muscular strength and flexibility on both sides of the trunk- the trunk and hip flexors anteriorly and the trunk and spinal extensors posteriorly. Postural deviations in the Spine: ACE PERSONAL TRAINER MANUAL 5 TH EDITION Chapter 1. Lordosis: Increased anterior lumbar curve (pelvis tilted forward/ overarched lower back) Kyphosis: Increased posterior thoracic curve (rounded upper back) Muscle imbalances associated with Lordosis and Kyphosis Posture Facilitated/ Hypertonic (shortened/ tight) Inhibited (lengthened/ hypotonic/ weak/ underactive) -------------------------------------------- ------------------------------------------------------ Hip Flexors Hip Extensors Lumbar extensors External obliques Anterior chest/ shoulders Upper-back extensors Latissimus Dorsi Scapular Stabilizers Neck Extensors Neck Flexors 2. Flat- Back Posture: Decreased anterior lumbar curve (pelvis tilted backwards) Muscle imbalances associated with Flat-Back posture Facilitated/ Hypertonic Inhibited (lengthened) ------------------------- ------------------------ Rectus Abdominus Iliacus/ psoas major Upper-back extensors Internal Obliques Neck Extensors Neck flexors Ankle plantar flexors Lumbar extensors 3. Sway-Back posture: Decreased anterior lumbar curve(flat-back) and increased posterior thoracic curve (kyphosis) Muscle imbalances associated with Sway-Back posture +-----------------------------------+-----------------------------------+ | Facilitated/ Hypertonic | Inhibited/ Lengthened | +===================================+===================================+ | Hamstrings | Iliacus/ Psoas Major | +-----------------------------------+-----------------------------------+ | Upper fibres of posterior | Rectus femoris | | obliques | | +-----------------------------------+-----------------------------------+ | Lumbar extensors | External Obliques | +-----------------------------------+-----------------------------------+ | Neck extensors | Neck flexors | | | | | | Upper-back extensors | +-----------------------------------+-----------------------------------+ Muscle imbalances and postural deviations can be attributed to many factors that are both correctible and non-correctible, including the following. - Correctible factors: Repetitive movements (muscular pattern overload) Awkward positions and movements (habitually poor posture) Side dominance Lack of joint stability Lack of joint mobility Imbalanced strength-training programs - Non- Correctible factors: Congenital conditions (e.g. scoliosis) Some pathologies (e.g. rheumatoid arthritis) Structural deviations (e.g. tibial or femoral torsion, or femoral anteversion) Certain types of traumas (e.g. surgery, injury or amputation) Personal trainers should focus on the obvious, gross imbalances and avoid getting caught up in minor postural asymmetries. Ankle pronation and supination and its effect on tibial and femoral rotation:  - Both feet should face forward in parallel or with slight (8-10 degrees) external rotation. The toes should be aligned in the same direction of the feet and any excessive pronation or supination at the subtalar joint should be noted. - As pronation tends to move the heel into eversion, this may actually lift the outside of the heel slightly off the ground (moving the ankle into plantar flexion). In turn, this may tighten the calf muscles and potentially limit ankle dorsiflexion, but trainers should keep in mind that the opposite is also true. A tight gastrocnemius and soleus complex may force heel eversion in an otherwise neutral subtalar joint position. Subtalar Joint Movement Foot movement Tibial (knee) movement Femoral movement --------------------------- --------------- ------------------------ ------------------- Subtalar joint pronation Eversion Internal Rotation Internal rotation Subtalar Joint Supination Inversion External rotation. External Rotation Hip Adduction: - In standing and in gait, hip adduction is a lateral tilt of the pelvis that elevates one hip higher that the other (also called "hip hiking") which may be evident in individuals who have a limb-length discrepancy. - If a person raises the right hip, the spine tilts to the lift moving the right thigh closer to the line of gravity (imaginary line passing through the center). This position progressively lengthens and weaken the right hip abductors, which are unable to hold the hip level (Sleeping on one side/ women carrying children on one side). Observation Position Plumb line alignment --------------------- --------------------------- ---------------------------- Right hip adduction Elevated (vs. left side) Hips usually shifted right Left hip adduction Elevated (vs. right side) Hips usually shifted left Pelvic Tilting - Anterior tilting of the pelvis frequently occurs in individuals with tight hip flexors, which is generally associated with sedentary lifestyles where individuals spend countless hours in seated positions. - Tight or over dominant hip flexors are generally coupled with tight erector spinae muscles, producing an anterior pelvic tilt, while tight or over dominant rectus abdominis muscles are generally coupled with tight hamstrings, producing a Posterior pelvic tilt. This coupling relationship between tight hip flexors and erector spinae is defined as Lower-Cross Syndrome. - With foot pronation and accompanying internal femoral rotation, the pelvis may tilt anteriorly to better accommodate the head of the femur, demonstrating the point of an integrated kinetic chain whereby foot pronation can increase lumbar lordosis due to an anterior pelvic tilt. Anterior Tilt Posterior Tilt ------------------------------------ ----------------------------------------------------------------- ---------------------------------- Rotation ASIS (anterior superior iliac spine) tilts downward and forward ASIS tilts upwards and backwards Muscles suspected to be tight Hip flexors and Erector Spinae Rectus Abdominus and Hamstrings Muscles suspected to be lengthened Hamstrings and Rectus Abdominis Hip Flexors and Erector spinae Shoulder and Thoracic Spine Correct Cues for Scapular Motion Limitations and compensations to movement at the shoulder occur frequently due to the complex nature of the shoulder girdle design and varied movements performed at the shoulder. Shoulder movements are performed with a collaborative effort between the glenohumeral joint (120 degrees) and the scapulothoracic region (60 degrees). Observation Muscles suspected to be tight ------------------------------- --------------------------------------------------------------------------- Shoulders not in level Upper trapezius, levator scapulae, rhomboids Asymmetry to midline Lateral trunk flexors (flexed side) Protracted (forward, rounded) Serratus anterior, anterior scapulohumeral muscles, upper trapezius Medially rotated humerus Pectoralis major and latissimus dorsi (shoulder adductors), subscapularis Kyphosis and depressed chest Shoulder adductors, pectoralis minor, rectus abs, internal oblique. *Scapular winging and scapular protraction:* *While looking at the client from a posterior view, if the vertebral (medial) and/ or inferior angle of the scapulae protrude outward, this indicates an inability of the scapular stabilizers (primarily the rhomboids and serratus anterior) to hold the scapulae in place. Noticeable protrusion of the vertebral (medial) border outward is termed as "scapular protraction", while protrusion of the inferior angle and vertebral (medial) border outward is termed "winged scapulae".* Head position: With good posture, the earlobe should align approximately over the acromion process, but given the many awkward postures and repetitive motions of daily life, a forward-head position is very common where the head does not tilt downward, but simply shifts it forward so that the earlobe appears significantly forward of the acromioclavicular joint. Observation Muscles suspected to be tight ----------------------- -------------------------------------------------------------- Forward-head position Cervical spine extensors, upper trapezius, levator scapulae. How someone performs a squat can tell you a lot about their lower extremity mobility and stability. +-------------+-------------+-------------+-------------+-------------+ | View | Joint | Compensatio | Key | Key | | | location | n | suspected | suspected | | | | | compensatio | compensatio | | | | | ns: | ns: | | | | | Overactive | Underactive | | | | | (tight) | (lengthened | | | | | | ) | +=============+=============+=============+=============+=============+ | Anterior | Feet | Lack of | Soleus; | Medial | | | | foot | lateral | gastrocnemi | | | | stability: | gastrocnemi | us, | | | | ankles | us, | gracilis, | | | | collapse | peroneals | sartorious, | | | | inward/ | | tibialis | | | | feet turn | | group | | | | outward | | | +-------------+-------------+-------------+-------------+-------------+ | Anterior | Knees | Move inward | Hip | Gluteus | | | | | adductors, | maximus and | | | | | TFL | medius | +-------------+-------------+-------------+-------------+-------------+ | Anterior | Torso | Lateral | Side | and muscle | | | | shift to a | dominance | | | | | side | | potential | | | | | imbalance | lack of | | | | | due to | | | | | | | lower | | | | | stability | extremity | | | | | in the | | | | | | | loading. | | | | | during | | | | | | joint | | +-------------+-------------+-------------+-------------+-------------+ | Sagittal | Feet | Unable to | Plantor | None | | | | keep heels | flexors | | | | | in contact | | | | | | with the | | | | | | floor | | | +-------------+-------------+-------------+-------------+-------------+ | Sagittal | Hip and | Initiation | Movement | Initiated | | | Knee | of movement | | at the | | | | | knees may | | | | | | | Indicate | | | | | quadraceps | | | | | | and | hip flexor | | | | | | | | | | | dominance, | well as | | | | | as | | | | | | | activation | | | | | insufficien | of the | | | | | t | | | | | | | | | | | | gluteus | | | | | | group. | | +-------------+-------------+-------------+-------------+-------------+ | Sagittal | Tibia and | Unable to | Poor | lack of | | | torso | achieve | mechanics, | | | | relationshi | parallel | | to tight | | | ps | between | Dorsiflexio | plantar | | | | tibia and | n | | | | Contact | torso. | due | normally | | | behind knee | | | allow | | | | Hamstrings | flexors | | | | | contact | (which | forward). | | | | back of | | | | | | calves | the tibia | Weakness | | | | | to move | and | | | | | | | | | | | Muscles | Resulting | | | | | | in an | | | | | poor | | | | | | mechanics | Stabilize | | | | | | and | | | | | inability | | | | | | to | Lowering | | | | | | phase. | | | | | control the | | +-------------+-------------+-------------+-------------+-------------+ | Sagittal | Lumbar and | Back | Hip | Core, | | | thoracic | excessively | flexors, | rectus | | | spine | arches | back | abdominus, | | | | | extensors, | gluteal | | | | Back rounds | latissimus | group, | | | | forward | dorsi. | hamstrings. | | | | | | | | | | | Latissimus | Upper back | | | | | dorsi, | extensors. | | | | | teres | | | | | | major, | | | | | | pectoralis | | | | | | major and | | | | | | minor | | +-------------+-------------+-------------+-------------+-------------+ | Sagittal | Head | Downward | Increased | Trunk | | | | | hip and | flexion. | | | | Upward | | | | | | | Compression | and | | | | | | tightness | | | | | the | in | | | | | cervical | | | | | | | extensor | | | | | | region. | +-------------+-------------+-------------+-------------+-------------+