Applied Physiology Notes Weeks 8-11

what is a squat?

a movement that involves lowering the body by moving into deep knee and hip flexion and then standing back pu

what are the most popular squat variations?

• high bar back squat

• low bar back squat: bare across the rear delts, allowing for more weight to be moved due to a shorter moment arm

• front squat

• zercher squat: bar is held in the elbows so this is helpful for someone who doesnt have shoulder or wrist mobility

• hack squat: very quad specific as it creates a long moment arm to the knees

• safety bar squat

• overhead squat: typically seen in olympic lifting or crossfit as it requires more mobility as multiple joints

in order to complete a barbell back squat, one must overcome what flexor moments?

spinal, hip, knee, and ankle

discuss the spinal flexor moment during a squat.

depends on…

• the horizontal distance from the center of the mass: increased torso inclincation=increased moment arm

• the intervertebral joints as well as the load on the bar: increased load=increased moment arm

discuss the hip flexor moment during a squat.

depends on…

• the horizontal distance between the hips and the COM of the bar plus the upper body: increased torso inclination=increased moment arm

• the load above the hips

discuss the knee flexor moment during a squat

depends on the horizontal distance between the knees and the COM of the bar plus upper body

• increased torso inclination=decreased moment arm

• knee shifting forward/increased tibia angle= increased moment arm

• squat depth

depends on the load above the knees

discuss the plantarflexor moment during a squat.

depends on the horizontal distance between the center of pressure on the foot and the ankle joint.

• weight more in the toes=increased moment

• weight more in the heels=decreased moment

depends on the load on the bar and body

what muscles do squats effect?

• vasti muscles experience substantial growth with half squats and full depth squats. they are working hard even at low loads at any given squat depth.

• adductors and glutes experience some growth with half squats and stubstantial growth with full squats. the deeper and heavier you squat, the more these hip extensors will work. out hip extensors will be what eventually causes us to fails because they cannot overcome the hip flexor moment

• rectus femoris and hamstrings experience no to minimal muscle growth with all squat depth— because two joint muscle

does squat stance width matter?

• it is influenced by how the bones of your hip are shaped, the direction your acetabulum points, soft tissue mobility and strengths, and personal comfort.

• the only muscle usage difference are increased glute activity and maybe increased adductor activity

what is a deadlift?

picking up an object from a dead stop on the floor

what are common deadlift patterns?

• barbell conventional deadlift: grip wider than feet, hold it closer to COG, more of a hip hinge

• barbell sumo deadlift: feet wider than grip, more dependent on knee extension strength but not as much as a squat

• deficit deadlift: allows you to get more ROM

• snatch grip deadlift: bigger ROM and pulls on scapula retractors more

• trap bar deadlift: can lift more weight like this as its closer to a squat

what are the deadlift demands one must overcome?

• spinal flexor moment

• hip flexor moment

• knee flexor moment

discuss the spinal flexor moment during a deadlift.

• depends on the horizontal distance from the COM and the intervertebral joints: increased torso inclincation = increased moment arm

• depends on the load on the bar: increased load = increasing moment

• in a conventional deadlift the torso starts closer to the floor which results in an increased moment arm from the barbell to each intervertebral joint

• in a sumo deadlifr, torso angle will be more upright which results in a decreased moment arm from the barbell to each intervertebral joint

discuss the hip flexor moment during a deadlift.

• depends on the horizontal distance between the hips and the barbell and is highest at the start at the lift for both conventional and sumo squats

• depends on the load on the bar

discuss the knee flexor moment during a deadlift.

depends on the horizontal distance between the knees and the barbell

• in a barbell deadlift, the knee extension demands from the weight are much lower than squats as the barbell is basically on the knee joint

• trap bar deadlifts allow more forward and backward knee travel and knee extension demands change more similarly to squats

depends on the load on teh barbell

in sumo deadlifts, the knee extensors contribute more because the feet are mor anchored to the floor and push out more laterally

big picture, what is the difference between conventional vs sumo deadlifts?

• conventional deadlifts have higher spinal extension demands

• sumo deadlifts havae higher knee extension demands

• hip extention demands are similar

what are the types of grip we can use when deadlifting?

• double overhand: this is weakest because the bar can pull down and roll

• mixed grip: best grip as it prevents the bar from pulling down but it is assymetrical

• hook grip: also helps prevent the bar from being pulled down. it is symmetrical but hurts the thumbs

• straps

what are the limiting factors of a deadlift?

hip extensor and spinal extensor strength

grip strength

what muscles do deadlifts affect?

erector spinae, glute max, hamstrings, and quads

what are the biggest deadlift injuries we see?

intervertebral disc herniations that typically occur in more lumbar flexion. yet, having a flexed lumbar spine postures are associated with greater strength and efficiency during a maximal lift in pain free individuals

what does aging look like?

physical function, mental/cognitive function, happiness all have a exponential decline after we hit middle age. however, the goal would be to extend how we function, think, and improve general well being.

t/f life expectancy is improving.

true

what is the economic impact of aging?

• medicare expenditures are up to 1.3 trillion

• the number of workers per medicare enrollees is expected to decrease from 3.5 - 2.4 by 2030

what functional changes do we see occur over the lifetime?

• balance decreases significantly after that age of 50

• walking speed decreases

• running speed decreases

• grip strength decreases which is our strongest predictor of all cause mortality

• physical activity decreases

do we age because we play less or do we play less because we age?

both, it is a viscious cycle

what are the age related changes in skeletal muscle?

• reduction in fiber size (type 2)

• reduction in fiber number

• denervation

what is sarcopenia and why does it occur?

sarcopenia is muscle failure; low muscle strength and mass and poor physical performance associated with aging but can occur at earlier ages

it occurs due to…

• decrease in physical activity and exercise

• decrease in the number of muscle fibers

• loss of motor neurons

• hormonal changes

what is physical activity versus exercise?

physical activity: just doing anything above rest

exercise: intentional, structures, planned, progressed targeted at manageing components of physical activity

what does resistance training improve in aging skeletal muscle?

increased strength, power, rate of force development, muscle CSA and volume

what does aerobic training improve in aging skeletal muscle?

increased mitochondria content and capillary density

what is osteporosis vs osteopenia? what is osteoarthritis?

osteporosis: removal of old bone greater than the creation of new bone

osteopenia: precursor for osteoporosis

osteoarthritis: degeneration of joint surfaces

what are the sex differences with changes in BMD during aging?

females are at a higher risk for osteoporosis after menopause due to decreased estrogen

what does resistance training improve in the aging skeletal system?

• females: increased BMD or equal BMD

• males: 1-3% of increased BMD

• changes may be site specific

• high load intensities=most beneficial

• frequency 3-4 times a week

• multiples sets may be beneficial

what does aerobic training improve in the aging skeletal system?

• higher intensity=greater stress on bone

• high velocity movements

• use in conjunction with resistance training program

what are the age related changes we see in the cardiovascular system?

• increased risk for coronary artery disease— heart attack

• increased hypertension— increased SBP and risk for stroke

• increase in arterial stiffness and thickness— leads to changes in left ventricular structure and function

what are the age related changes we see in the pulmonary system?

• increased risk for pulmonary disease— COPD, smoking or environmental factors

• structural changes of the thoracic cavity

• functional changes in muscle strength

how does resistance training help improve the cardiovascular system in the aging individual?

• strength is a foundation to endurance training

• increases functional capacity

• some benefit to BP

• some cardio-respiratory benefit in deconditioned

• have them do lower intensity or circuit training

how does aerobic training help improve the cardiovascular system in the aging individual?

• increased VO2

• decreased BP

• decreased HR at submaximal levels

• 2-3x per week

• 50-80% maximum heart rate

• 20-30 mins

what are the age related changes in the central nervous system?

• neuronal atrophy in the cerebral cortex

• neural reorganization leads to reduced neuroplasticity

what are the age related changes to peripheral nerves?

• gradual loss of spinal motor neurons

• reduced number and diameter of motor neuron axons which leads to the gradual loss of motor units

how does resistance training help improve the aging nervous system?

moderate to high intenstiy exercise will…

• increase motor neuron firing frequency

• decreased antagonist co-activation

• may be helpful for motor control

• may be helpful for cognitive function

how does aerobic training help improve the aging nervous system?

moderate to high intensity exercise will…

• improve executive function

• improve perceptual speed

• potentially impact neuroplasticity

what is the working alliance?

• it is an important determinant of treatment outcomes

• the therapist and patient agree on treatment goals and interventions and have an affective bond

• this positive alliance is correlated with positive health outcomes, specifically accounting for 50% of the beneficial effects of psychotherapy

• good working alliance anda satisfaction with training when providing positive feedback, answering patient questions, providing clear instructions for home practice

what is mental health versus mental illness/disorder?

mental health: an overall assessment of mental well-being or lack thereof

mental illness/disorder (MI): condition that affects a person’s thinking, feeling, or mood

what are the two types of mental illnesses?

any MI (AMI): mental, behavioral, or emotional disorder. varying impairments

serious MI (SMI): AMI taht results in functional impairments. limits one or more major life activities

how do we classify mental disorders?

• mood (depression, dysthymia, bipolar)

• anxiety

• substance related

• trauma and stressor related

• schizophrnia and psychotic

• neurodevelopmental (intellectual)

• neurocognitive (alzhimers, PD, TBI)

• eating disorders

what is depression?

1. five or more of the following symptoms present during a 2 week period with at least one of the symptoms being a depressed mood or anhedionia

2. symptoms cause clinical significant distress or impairment in osical, occupational, or other important areas of functioning

3. episode is not attributed to the physiologic affects of a substance or another medical condition

what are the symptoms of depression?

• depressed mood most of the day

• markedly diminished interest or pleasure in almost all activities nearly everyday

• significant appetite change or weight loss or gain

• insomnia or hypersonmia almost everyday

• psychomotor agitation or retardation

• fatigue or loss of energy

• feeling of worthlessness or excessive guild

• diminished ability to think, concentrate, or make decisions

what is the most common mental health disorder in the united states?

depression; it is alsto 2x more likely in females

compared to patients without depression, patients with depression…

• have poorer outcomes

• are less compliant with treatment

• have reduced treatment response

• have greater healthcare costs

why is a patients metal state important for physical therapists to consider?

• patients will be in a vulnerable states

• contact time with patients significantly greater than physicians

• mental health assessments in rehab are not required in the US

• patients progress can be influenced by their mental health

individuals with depression have worst rehab outcomes in what ways?

increased…

• pain

• medication use

• infections

• disability

• healthcare utilization

• length of stay

• cost mortality

decreased…

• independence in ADLs

• mobility

• subjective health

• quality of life

• involvement in leisure activities

• likelihood returning to work or school

what are the potential impacts of exercise on depression?

physiological:

• increased neuroplasticity

• increasined monoamine levels

• increased BDNF

• decreased cirulating cortisol

psychological:

• increased self efficacy

• increased self esteem

• increased social contact

• decreased negative thought rumination

discuss the use of neuroplasticity as a model of depression.

• transcranial magnetic stimulation is used to probe the CNS and measure muscle activity when the corresponding area of the brain is stimulated

• subjects with depression demonstrate reduced motor cortex plasticity which impairs motor learning

• BDNF is reduced in depression

• but we see that neuroplasticity is restored when depression symtoms remit following pharmacotherapeutic intervention

what are the types of overhead presses?

• strict barbell overhead press

• barbell push press

• barbell push/power jerk

• barbell split jerk

• barbell squat jerk

• dumbell strict press/push press/jerk

• log press

what overhead press demands must we overcome?

• elbow flexion moment: primarily triceps

• shoulder extension and adduction moment: primarily front and middle delt, pec major depending on agnle of press

• scpaular downward rotation and depression moments: primarily upper traps, serratus anterior, som elower traps, but basically everything around the scapulae at various point of the overhead press

how does the grip width matter during an overhead press?

• with the arms straight overhead from the shoulders, 50% of the implement weight is in each hand

• with the arms at a 75 degree angle from each other, each arm will be resisting a force equal to 63%

• with the arms at a 90 degree angle from each other, each arm will be resisting a force equal to 71%

• so, most people can get further into shoulder flexion with a wider grip which provides more stability and strength

the torso position of an overhead squat will depend on…

• the size and shape of the implement being pressed

• limb lengths and segment lengths of the individual

• flexibility of the individual

• strength of the individual

• the COM of the weight must remain very close to horizontal of the COm of the individual

what limits overhead pressing?

• for strict press, likely anterior delt or triceps

• for leg drive variations, it could be upper body strength, lower body strength, or the skill in the specific movement

what is the most strongly supported mechanism for muscle hypertrophy?

mechanical tension

how does mechanical tension induce hypertrophy?

henneman’s size principle:

• at over 90% of loads, all available motor units are recruited from the start rather than type I being recruited vefore type II as seen in under 90% loads. this places the individual muscle fibers under high levels of mechanical tension

range of motion:

• training at longth muscle lengths induces more hypertrophy than training at short muscle lengths

what muscles get bigger with overhead pressing and pullups?

basically all of them— delts, biceps, brachioradialis, pecs, traps, lats, infraspinatus

what is overweight/obesity?

• too much weight for height

• excess fat mass for age/stage

• BMI>25

what is dynapenia?

loss of muscle strength that occurs with age

what is cachexia?

weakness and wasting of the body due to severe chronic illness

what is the problems of obesity by age?

1/5 of individuals below 18 are considered obese. specifically younger females and then older men

there is a high correlation between BMI and ______.

all cause mortality

what are the health implications associated with obesity?

• heart disease/conditions: hypertension, dyslipidemia, coronary heart disease

• type 2 diabetes

• 13 different types of cancer

• stroke

• osteoarthritis

• sleep and breathing problems

• poor health related quality of life, including mental health

• poor physical functioning

how does obesity increase the risk for chronic disease?

it leads to chronic, low-grade, systemic inflammation

what are the physical limitations we see in those who are obese?

• walking ¼ a mile

• walking up 10 steps without resting

• standing or being on the feet for 2 hours

• sitting for 2 hours

• stopping, bending, or kneeling

• reaching up overhead

• using figers to grasp/handle small objects

• lifting or carrying item as heavy as 10 pounds

the risk for functional decline is ____% greater for people with BMI>30

60%

what is muscle quality?

strength/power per mass/volume

it is the key to physical function

is the problem in obest individuals the load to be moved or the ability to move the load?

both

what is the problem with weight loss if not done well in those who are obese?

• it leads to muscle and bone loss that increases the risk for sacropenia and osteoporosis

• absolute weight loss depends on the rate and degree of weight loss, diet quality, exercise and physical activity, and hormones

what is the obesity paradox in regards to strokes?

after a stroke, obesity leads to increased disability and increased stroke recurrance. however, during acute rehab to as a result of paralysis and a lack of ability to move we see decrease in muscle mass and function which then leads to increased weight

discuss obesity in children with neurological conditions.

the energy needs for children with neurological conditions are 60-70% of neurotypical children. so, we may see they have a higher body fat percentage at lower BMIs which is associated with decreased function. yet at the same time, they may actually have nutrient deficits so then you wouldnt want to encourage weight loss

what are the musculoskeletal effects on the lower body in those who are obese?

• greater risk of injury during ADLs

• increased joint weight bearing

• joint space narrowing and adaptations to gait kinematics

• excessive body weight negatively affects balance

• increased fatigue

discuss the effects of obesity on depression and anxiety.

• BMI >40 makes an individual 5x more likely to experience major depressive episodes in the past year

• the relationship between obesity and depression appears stronger in women than men

• weight loss decreases symptoms of depression and anxiety

what are the weight management guidlines?

1. lifestyle intervention: diet, PA, behavioral modification if someones has a BMI >25

2. pharmacological intervention if someone has a BMI >25 with comorbidities or 30 without comorbidities

3. surgical intervnetion is someone has a BMI >35 with comorbidites or 40 without comorbidities

what is the redommended caloric intake to lose weight?

500-1000 kcal/day in order to lose 1 lb/wk

what are the weight management guidlines regarding diet?

• higher protein intake

• reduced carbohydrate intake

• low fat intake

what are the weight management guidlines regarding physical activity?

for weight loss, at least 150 minutes moderate intensity or 75 min vigorous intensity both aerobic and strength training

for weight loss maintenance, at least 200-300 minutes moderate intensity per week

what is weight bias?

the belief that people with obesity are lazy, lack self control, or non-compliant with weight management intervention. this increases the likelihood of maladaptive eating behavior, avoidance, and cancellation of health screenings and other appointments, poorer obesity treatment outcomes

what are macronutrients?

provides energy for the system

carbs, proteins, fats

what is a carbohydrate?

monosaccharides, disaccharides, polysaccharides

what ist the role of carbs in the body?

• breakdown to glucose for immediate energy

• fuel source for high intensity exercise

• stored in the muscle and liver for later use

• 4 calories per gram of carboydrate

what are the carboydrate types?

simple: sugars (sucrose, lactose, maltose)— candy, honey, fruit

complex: starches (rice, potatoes, veggies), fiber, glycogen

what is soluble fiber?

• dissolves in water and is gel like

• increases satiety

• role in managing blood glucose and blood lipids

• ex: beans, oatmeal

what is insoluble fiber?

• does not dissolve in water

• promotes bowel regularity by helping other things move and increasing bulk

• ex: anything with bran— corn, brown rice, some veggies

what are fiber rich foods?

• whole grains

• fruits

• veggies

• nuts and seeds

what is the role of lipids/fats?

• provide energy (9 cal/g)

• cellular structure

• nutrient absorption

• promote healthy brain function

what are the types of fatty acids?

saturated: no double or triple bonds between carbon atoms. solid at room temp

monunsaturated: one bond that is unsaturated. liquid at room temp

polyunsaturated: multiple bonds that are unsaturated. liquid at room temp

trans fatty acids: found in processed foods

what are saturated fat rich foods?

• butter, coconut oil

• cheese

• processed foods

• pastries

what is the recommended about of calories from saturated fat?

<10% total calories

what are monounsaturated rich foods?

avocado, olives, nuts, and their associated oils

what are polyunsaturated fat rich foods?

• omega 3 and omega 6: ideally have a 1×1 ratio but average person has 1×20

• EPA and DHA

• omega 3 foods: vegetable and seed oils, cold water fish, breast milk

what is a protein?

a group of amino acids; big tangles of polypeptides

what is the role of protein?

supports lean body mass

increases satiety

muscle protein synthesis

where can you find protein?

• all food groups except fruit

• meat, poultry, and fish are the best sources

• eggs and dairy

• beans and grains together create a complentary complete protein

what are micronutrients?

vitamins and minerals