Older Adult Exercise Prescription Flashcards
By 2030, 20% of US population will be over the age of
65
Older adults and inactivity
60% of adults have reported little or no leisure-time activity
sedentary lifestyle is a big problem
older adults often stop exercise –> but they would benefit the most
Changes in the nervous system with aging:
PNS
-structural, functional, and biochemical changes of the nerves
-loss of myelinated nerve fibers
-decreased nerve regeneration and re-innervation of muscle
CNS
-decreases in muscle activation
soft tissue changes with age
changes in flexibility and compliance
-collagen more cross-linked–> greater stiffness of ligaments and tendons
-elastin undergoes structural changes->reduced tissue recoil and stretch
-decreased water content of connective tissue
MSK changes with aging- bone
osteopenia: between 1and 2.5 SD below avg (bone density/g/cm2)
osteoporosis: less than 2.5 SD below avg (bone density/g/cm2)
Progressive loss of bone mineral
density leads to a disruption in
microarchitechture; more susceptible
to fracture
-women are more at risk of BMD losses
MSK System changes with aging- muscle
-sarcopenia
-age-related loss of muscle mass
MUSCLE STRENGTH:
-1.5-3% decrease every year over age 50
-morphological, physiological, and central activation changes–> decreased muscle strength
-greater changes in strength LE > UE and proximal > distal
Morphological changes in muscle
-decreased total number of fibers (type I and II)
-preferential atrophy type II fibers (fast glycolytic)
-loss of MU’s with increase in size of remaining motor units –> decreased grading of fine motor movements
-increase in intramuscular fat
Whole muscle study
18% smaller fibers in older adults
25% lower number of fibers in older adults
Phys changes with aging
-slower contractile properties
–> slower to peak tension
–> slower rate of relaxation
-decreased maximum shortening velocity
–> power based activities affected
-possible impairments in excitation contraction coupling
-possible changes in oxidative and glycolytic enzymes
-metabolism at less risk of changing with active lifestyle
Central activation deficits with aging
-5-6% decrease in muscle activation with aging
-may magnify weakness from morphological and physiological causes
-age-related central activation deficits vary from muscle to muscle
Protein needs in older adults
greater protein turnover with increasing age
inadequate dietary protein intake may be an important cause of sarcopenia
1-1.5 grams per kilogram of bodyweight is needed if no kidney disease or diabetes –> 68-102 grams of high quality protein per day for person weighing 150 lbs
0.5 g of protein per lb of body weight
Mobility and balance changes
-joint stiffness changes
-increase in co-contraction of antagonist muscles –> decrease coordination
-changes in VOR
-slower postural responses (20-30 ms delay)
–> changes in sensory weighting
Strength training in older adults
HIRT CAN:
-offset muscle mass and strength losses
-decrease the risk for OP
-increase BMR
Endurance training in older adults
-improve CV health
-improve CV response to aerobic exercise
Age related CV system changes
-progressive degeneration of cardiac structures
-loss of elasticity, fibrotic changes of valves, infiltration of fat
-decreased contractility of the heart’s left ventricular wall–> decreased pumping capability
-decreased arterial elasticity
-decreased venous elasticity
-decreased aorta elasticity –> blood leaving the LV of the heart faces more resistance
-valves of the heart become stiffer
-walls become thicker
- INCREASE COLLAGEN AND DECREASE ELASTIN
