Lecture 18 Flashcards
Lecture 18:
How are active people 50+ different than sedentary peers
Adults who are recreationally and competitively engaged in exercise/sport are more fit than their older sedentary peers
Lecture 18:
Why is exercise int into old age an unusual pattern?
Because there is a natural tendency to be sedentary when older
Lecture 18:
What is Primary Aging?
The idea that we get chronologically get older & that increase in age alone impacts our bodies physiology but also how activity has an influence on it
Lecture 18:
When discussing primary ageing, what are some comorbidities of age?
- looks at cross-sectional vs longitudinal studies
Medical care, diet, & lifestyle factors can be comorbidities
Lecture 18:
What is Selective Mortality?
Selective mortality = natural decrease in our population as it gets older & makes it more challenging;longing to study responses of primary aging
Lecture 18:
What happens to height as you age & why?
Height decreases with age, around 35-40 years old
Initial decrease caused by compression of intervertebral discs & poor posture but later on (moreso in women) decrease is due to osteopenia & osteoporosis (decreases in bone mineral density)
Lectrue 18:
What happens to weight when you age?
1.) Weight increases from 25-45 years old due to decrease in physical activity & increased caloric intake (causes caloric imbalance)
2.) Weight then decreases around 65+ years old due to loss of body mass from decreased appetite (which contributes to muscle atrophy)
Lecture 18:
What happens to body fat %/content with age?
Body fat content tends to increase (increases more when sedentary & less when active *variation based on level of activity)
- older athletes decrease body fat content & central adiposity
Lecture 18:’
What happens to fat free mass (FFM) levels with age?
- what age do we see a change?
Fat-Free Mass decrease starts around age 40 due to…
- decreased muscle & bone mass
- sarcopenia (protein synthesis decreases as protein content reduced)
- due to lack of activity (in part)
- decreased growth hormone, including-like growth factor 1, etc
Lecture 18:
What happens to bone mineral content with age?
Bone mineral content decreases with age as bone resorption > bone synthesis
- this is due to lack of weight-bearing exercise
Lecture 18:
What are 4 body composition variables of aging?
1.) body weight
2.) percent body fat
3.) fat mass
4.) fat-free mass (FFM)
Lecture 18:
What are the key age-related changes in body composition that occur with training?
- what allows the biggest results?
1.) decreased weight, % body fat, & fat mass
2.) increased FFM (a lot more likely to increase with resistance training than aerobic training)
3.) moreso see this response in men than in women
*biggest results come with caloric restriction diet (500-1000kcal) & exercise
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to strength & neuromuscular function with age?
Strength & neuromuscular function decrease with age Which interferes either activities used for daily living
- occurs at about 50-60 years old & results from decrease in muscle mass
Lecture 18:
How do you offset strength loss with age?
Strength decrease is offset by resistance training/exercise
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to type II muscle fibres?
Type II fibre loss occurs with age as we see;
- decrease in type II motor neurons
- type I neurons innervating only type II fibres
- higher % of type I fibres
*training slows or stops fibre-type change (reduces loss of type II)
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to the size & # of muscle fibres?
Size & # of muscle fibres decreases with age
- size of both types decreases
- loss of 10% of fibres per decade after age 50
Lecture 18:
When discussing physiological responses to acute exercise with age; how does endurance training vs resistance training help with decline in muscle mass?
1.) endurance training has no impact on decline in muscle mass with age
2.) resistance training decreases muscle atrophy & increases muscle cross-sectional area
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to reflexes?
Reflexes slow with age but exercise preserves reflex response time
- active older people have similar reflexes to young active people
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to motor unit activation?
Motor unit activation decreases with age but exercises allows you to maintain maximal recruitment of muscle
- strength decrease may result from local muscle factors
Lecture 18:
How does exercise maintain muscle physiology?
The number of capillaries remains unchanged & oxidative enzyme activity id only slightly reduced
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to mitochondrial function?
- 3 things that are reduced?
Mitochondrial function declines with age
- 1.) reduced mitochondrial protein synthesis
- 2.) reduced mitochondrial respiration
- 3.) reduced maximal rate of ATP production
Lecture 18:
When discussing physiological responses to acute exercise with age; what does the decrease in mitochondrial function contribute to?
- how can this improve?
Decline in mitochondrial function contributes to muscle atrophy
- increased intracellular oxidative stress interferes with myofillament function but may be improved by exercise training
Lecture 18:
What happens to central & peripheral cardiovascular abilities with age?
Central & peripheral cardiovascular decrements are experienced with age
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to maximal HR?
Maximal HR is reduced
- reduction varies considerably but is the same for active & sedentary people
- electrical & receptor changes with age
* changes by about 1bpm per year {HRmax = 208-(0.7 x age)}
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to maximal stroke volume?
- what are a few results of this?
Maximal stroke volume decreases with age as the hearts contractility decreases in response to catecholamines
- Frank-starling mechanism partially lost
- Left Ventricle & arterial stiffening
- decline in Stroke Volume max attenuated by exercise
Lecture 18:
When discussing physiological responses to acute exercise with age; what happens to VO2 max & why?
VO2max decreases with age due to decrease in cardiac max output
- more-so as a result of decreased HR max & less to decreased SV max
- decline in VO2max is slowed by exercise (helps maintain it)
Lecture 18:
What does sedentary habits lead to?
Lead to increased risk for vascular aging as cardiac and arterial compliance decrease
- endothelial dysfunction & reduces vasodilation will result from sedentary behaviour as well as
Lecture 18:
How does exercise help reduce the risk of vascular aging?
Exercise reduces the risk of health issues because…
- lowers the amount of arterial stiffening & endothelial dysfunction
- preserves vasodilator signalling
- research on proper exercise amount & cardiovascular benefit still hapening
Lecture 18:
What happens to peripheral blood flow with age?
Peripheral blood flow decreases with age about 10-15% reduced even with exercise
- occurs due to increased vasoconstriction and decreased vasodilation
- decreased blood flow is compensated for by increased O2 difference
Lecture 18:
What happens to respiratory function with sedentary aging?
Vital capacity decreases as residual volume increases & total lung capacity is unchanged
- less air exchange occurs
- decreased elasticity of lungs & chest wall with age but exercise capacity not limited
Lecture 18:
How is Ventilatory Capacity maintained with age?
Ventilatory capacity maintained by exercise
- pulmonary ventilation doesnt limit aerobic capacity & oxygen saturation remains high
Lecture 18:
What happens to VO2 max with age?
VO2max decreases with aging & decreases in normally active older people as we see a steady decline from 25-75 years
Lecture 18:
What percent of your VO2max is lost per year? Per decade?
~1% lost per year & ~10% per decade, from ages 25-75
Lecture 18:
What happens to VO2max in males in terms of % of decline?
1.) 5-6% decline per decade in active adults
2.) 3.6% decline over 25 years in elite athletes
3.) 15% decline per decade in previously active adults
Lecture 18:
What key aspect is VO2max decline related to?
Decline is related to intensity of training before & during aging
Lecture 18:
What are 5 key factors that affect rate of VO2max decline?
1.) Genetics
2.) General activity level
3.) Intensity & volume of training
4.) Age-related body composition changes
5.) Age range
Lecture 18:
What are some effects resistance training has on strength & aging?
Resistance training increases strength via fibre hypertrophy (~30%)& increases cross-sectional area of types I & II (neural adaptations)
Lecture 18:
What are the benefits of resistance training in older adults?
Increase muscle mass & size, increases bone mineral density, increases activities in daily living, & decreases fall risks
Lecture 18:
How does neuromuscular function change with age?
Aging reduces ability of the neuromuscular junction to adapt to training
Lecture 18:
How does exercise training help mobility with age?
Structured moderate physical activity can reduce major mobility disabilities
Lecture 18:
How does physical activity improve cognitive function with age?
Regular physical activity can delay cognitive decline
Lecture 18:
What happens to running performance with age?
Running performance decreases with age & rate of decline = dependent on distance
- decline accelerates after 60 years old
Lecture 18:
What happens to swimming performance with age?
Swimming performance decreases with age & accelerates after 70 years old
- decline is greater in women than men
Lecture 18:
What happens to cycling performance with age?
Cycling peaks between 25-35 years & speed then decreases by 0.7% per decade
Lecture 18:
What happens to weightlifting performance with age?
Peaks between 25 & 35 years than sum of lifts declines 1.8% per year
Lecture 18:
What are 3 reasons why older people have higher risks of death from hyperthermia?
1.) higher core temperature
2.) metabolic heat gain is related to absolute VO2
3.) heat loss is related to relative percent VO2max
Lecture 18:
What are 3 ways exercise training improves thermoregulation?
1.) improves skin vasodilation (convection)
2.) improves sweat rate (evaporation)
3.) improves redistribution of cardiac output
Lecture 18:
Are exercise and longevity related?
- 3 points
1.) mild caloric restriction increases longevity
2.) exercise may contribute to caloric balance
3.) exercise leads to compressions of mortality
Lecture 18:
What are 3 most common injuries older adults experience from exercise?
1.) tendon injury (rotator cuff, Achilles, etc)
2.) cartilage injury (meniscus, focal injuries, etc)
3.) stress fractures
