Chapter 17/21: Exercise for Special Populations Flashcards
signs and symptoms of diabetes
polydipsia, polyuria, unexplained weight loss, infections and cuts slow to heal, blurry vision, fatigue
for type 1 diabetics, what happens if they do not inject adequate insulin before exercise?
show in increase in plasma glucose
effects of normal insulin levels on liver glucose release, glucose uptake by muscle, and BG levels
increased liver glucose release, increase glucose uptake by muscle, BG levels remain constant
effects of hypoinsulinemia on liver glucose release, glucose uptake by muscle, and BG levels
increased glucose release from liver, less of an increase of glucose uptake my muscles, so BG levels increase
effects of hyperinsulinemia on liver glucose release, glucose uptake by muscle, and BG levels
increased glucose uptake by muscles, less of an increase in liver glucose release, leading to decreased BG levels
major concern for type 1 diabetics during exercise
hypoglycemia, may result in insulin shock
what lowers the odds of exercise-induced hypoglycemia?
regular exercise schedule
at what fasting glucose level should a type 1 diabetic avoid exercising?
fasting glucose > 300 mg/dl
when should a type 1 diabetic ingest carbs?
glucose < 100 mg/dl
where should the insulin injection site be for type 1 diabetics?
away from working muscle to prevent increased rate of uptake and hypoglycemia
relationship between exercise and type 2 diabetes
exercise is a primary treatment (treats obesity, helps control BG and reduce insulin resistance, helps treat CVD risk factors)
can a combo of diet and exercise eliminate need for diabetic drugs for type 2 diabetics?
yes
how does exercise improve glucose uptake?
muscle contraction causes translocation of GLUT-4 transporters to the cell surface
describe how blood glucose and insulin levels change in type 2 diabetics when they exercise vs not exercising
type 2 diabetics who exercise show a decreased spike in blood glucose levels with less of a spike in insulin compared to diabetics who don’t exercise (during an OGTT)
3 different ways airway is restricted in asthma
1) contraction of smooth muscle of airways
2) swelling of mucosal cells
3) hypersecretion of mucus
how is asthma diagnosed?
using pulmonary-function testing which assesses vital capacity and forced expiratory volume
define vital capacity
maximal volume of air expelled after maximum inhalation
define forced expiratory volume
volume of air expired in 1 second during maximal expiration
asthma triggers
allergens, exercise, stress
describe the asthma response to triggers
plasma cells produce IgE antibodies which attach to mast calls lining bronchial tube —> mast cells release inflammatory mediators
what is exercise-induced asthma caused by?
cooling and drying of respiratory tract which triggers release of chemical mediators and airway narrowing
if properly controlled, does EIA impair performance?
no
how is EIA diagnosed?
strenuous running at 85-90% of max HR, if forced expiratory volume decreases by 10% or more, EIA is indicated
why is there less of a decrease in FEV for asthmatic-swimming compared to asthmatic-running or cycling?
????
strategies for preventing an asthma attack during exercise
1) warmup (15 mins at 60% of VO2max)
2) perform short-duration exercise
3) use a mask or face mask in cold weather
treatment of EIA
B2-agonist in case of attack during exercise, or other medications
how do B2-agonists affect performance?
inhaled B2-agonists do not improve performance (too low of a dose) but ingested salbutamol (B2-agonists) does improve strength, anaerobic power, and endurance (10-20x inhaled dose)
normal BP
systolic < 120, diastolic < 80
elevated BP
systolic between 120-129, diastolic < 80
stage 1 hypertension
systolic 130-139, diastolic 80-89
stage 2 hypertension
systolic > 140, diastolic > 90
prevalence of hypertension
1/3 of U.S adults, and prevalence increases with age
how does hypertension affect vascular endothelium?
hypertension damages the endothelium, which predisposes the individual to atherosclerosis and other vascular pathologies
how does hypertension affect afterload?
increases afterload which leads to left ventricular hypertrophy, which is an important cause of heart failure
nonpharmacological treatments for hypertension
lose weight, limit alcohol intake, reduce sodium intake, eat diet rich in fruits and veggies, stop smoking, exercise
recommended exercise prescriptions for those with hypertension
frequency: aerobic exercise on most, if not all, days of the week
intensity: moderate
duration: 30-60 mins of continuous or intermittent (min of 10 min bouts) aerobic activity
mode: primarily aerobic exercise supplemented by resistance exercise
how does strength change with exercise in children? what does the extent of muscular development depend on?
increases as muscle mass increases with age, the extent of muscular development depends on relative maturation of the nervous system
how is thermoregulation different for children?
children have increased surface area:mass ratio so they have greater conductive heat loss and gain, they also have less evaporative heat loss leading to a slower heat acclimation
how is blood pressure different in children?
resting and submax blood pressure are lower in adults (relative to body size), they have smaller hearts and lower peripheral resistance during exercise
how are heart rate & stoke volume different in children? what affect does this have on cardiac output?
children have a higher HR, which almost compensates for the lower SV (smaller heart and lower BV), which results in a slightly lower cardiac output than an adult
how do children compensate for the slightly lower cardiac output?
a-vO2 difference increases to compensate
how does absolute VO2 max change with age in boys and girls?
increases with age
how does relative VO2 max change with age for boys and girls?
relative VO2max remains steady with boys, but decrease with age for girls (this is because boys produce more testosterone —> encourages lean muscle mass (which consumes more O2, whereas females obtain more fat mass)
how does lung function change with age in children?
lung volume and peak flow rate increase with age
how does children’s economy differ from adults?
child’s O2 consumption per kilogram is greater than adults, but with age, skills improved and stride lengthens
how does endurance running pace change in children with age? why? occurs regardless of what?
endurance running pace increases with age because of better economy of effort, regardless of VO2 max changes or training status
how does anaerobic performance in children compare to in adults?
children limited in anaerobic performance because of low muscle mass
how does the glycolytic capacity in children compare to that in adults?
children have a lower glycolytic capacity (less muscle glycogen, less glycolytic enzyme activity, and lower blood lactate)
how do the resting stores of ATP-PCr compare in children and adults?
similar in children and adults
pros and cons of strength training in children
historically controversial with concerns about damage to articular cartilage, epiphyseal growth plate, and muscle-tendon insertion
but, weight lifting is safe when proper technique and can promote muscular strength and bone density
2 physiological adaptations children experience with aerobic training
1) improvement in VO2 max similar to adults
2) performance increases due to improved running economy
3 physiological adaptations in children due to anaerobic training
1) higher resting PCr, ATP, glycogen
2) higher PFK activity
3) higher maximal blood lactate
how does early specialization in one sport affect lifelong fitness?
reduces the “fun” physical activities, which leads to reduced lifelong physical activity
cause of sudden cardiac death during exercise in children
congenital heart defects, not exercise
females’ responses to training are similar to males, with one exception, what is the exception?
thermoregulation is impaired during the luteal phase of menstrual cycle
athletic amenorrhea
cessation of menstruation
3 potential causes of athletic amenorrhea
1) amount of training
2) psychological stress
3) low energy availability
why would the body want to cease menstruation in female athletes?
allows the body to divert more resource to survival and key cellular mechanisms rather than reproduction
describe anorexia nervosa
extreme steps to reduce body weight (starvation, exercise, laxative use) which causes excessive weight loss, amenorrhea, and even death
describe anorexia bulimia
pattern of overeating followed by vomiting which leads to damaged teeth and esophagus
2 major causes of osteoporosis
1) estrogen deficiency due to amenorrhea
2) inadequate calcium intake due to eating disorders
how does the bone mineral content of female runners compare to untrained females?
female runners have a higher bone mineral content
describe RED-S
applies to both men and women, relative energy deficiency in sports
treatment of RED-S
1) increase energy intake and reduce energy expenditure
2) nutritional counseling and psychotherapy if practicing restrictive eating behaviors
how does recovery from RED-S progress?
recovery of energy status happens first, then recovery of menstrual status, then recovery of bone mineral density
3 reasons why female athletes are at a higher risk of certain knee injuries compared to men
1) fluctuation in hormones during menstrual cycle may compromise ACL strength and/or proprioreceptor feedback
2) knee anatomy (may be due to greater joint laxity)
3) dynamic neuromuscular imbalance (imbalanced strength, proprioception, and landing biomechanics)
major adaptations to pregnancy
increase in plasma volume, cardiac output, stroke volume, and heart rate, tidal volume and minute ventilation
exercise recommendations during pregnancy
regular endurance exercise poses little risk to the fetus and is beneficial to the mother, but pregnant women should consult their physician before beginning an exercise program
exercise during pregnancy reduces the risk of
gestational diabetes and preeclampsia
how do training adaptations differ during pregnancy?
1) absolute VO2 max is increased or maintained due to increased CO & O2 capacity
2) combo of training and pregnancy results in greater adaptations that training alone due to plasma volume increase
ASCM/CDC specific exercise recommendation for pregnant women
30 min/day of moderate-intensity activity on most, preferably all days
how should intensity be determined for exercising pregnant women?
RPE, heart rate (may not be best) and “talk test”
how should body temp be maintained for pregnant women while exercising?
limit body temp increases to less than 1.5 degrees celsius (aquatic exercise recommended)
how should exercising pregnant women maintain hydration?
consumer fluids at regular intervals (every 15 mins)
how should training change as pregnancy advances?
reduce intensity and volume as pregnancy advances
what sort of exercises should pregnant women avoid?
supine exercises
why is exercising into old age an unusual pattern?
natural tendency to be sedentary, unmotivated
potential motivating factors for older people to engage in physical activity
be fit enough to play with grandkids, maintain independence, social incentive
how does endurance performance change as you age?
endurance performance declines after age 60
how does VO2 max change with age?
declines about 1% per year
what two factors don’t really change with age?
exercise economy and lactate threshold
how does training affect the decline in VO2 max as you age?
training can slow but not prevent the decline in VO2 max
how does weight change with age?
from 25-45, decreased physical activity and increased caloric intake causes weight gain, when older than 65, loss of body mass and appetite causes weight loss
4 factors contributing to decreased fat-free mass starting around age 40
1) decreased muscle and bone mass
2) sarcopenia (decreased protein synthesis)
3) lack of activity
4) decreased growth hormone & IGF-1
2 factors contributing to loss of strength with age
1) lower level of activity
2) also due to sarcopenia (loss of muscle mass)
3 defining characteristics of sarcopenia
1) decrease in muscle size (both type I and II)
2) decrease in number of fibers (both type I and II)
3) greater reduction in type II fibers with aging
how does exercise affect reflexes in older people?
exercise preserves reflex response time so that active older adults are approx equal to young active people
how does motor unit activation change with age? how does exercise prevent this?
motor unit activation decreases; exercise retains maximal recruitment of muscle
how does bone mineral content change with age?
decrease; bone resorption > bone synthesis due to a lack of weight bearing exercise
why is osteoporosis more common in women?
due to lack of estrogen
recommendations for exercise to maintain bone health
frequency: weight bearing 3-5 times/week, resistance 2-3
intensity: moderate to high bone loading
duration: 30-60 mins/ day
mode: weight-bearing, jumping, resistance
