Chapter 17 & 21 Flashcards
what is in charge of synthesis of insulin in the pancreas
the beta cells
control of insulin release
increased plasma glucose causes increased insulin secretion which decreases plasma glucose
diabetes mellitus
a group of metabolic diseases characterized by an inability to produce enough insulin or use it properly
characterized by hyperglycemia
type 1 diabetes
does not produce enough insulin
type 2 diabetes
cells don’t respond to insulin
signs and symptoms of diabetes
polydipsia (excessive thirst)
polyuria (frequent urination)
unexplained weight loss
infections and cuts that are slow to heal
blurry vision
fatigue
effect of prolonged exercise in diabetics
those will well medicated and controlled diabetes are able to maintain close to normal blood glucose levels throughout exercise
those with type 1 diabetes who do not inject the adequate amount of insulin before exercise show a
increase in plasma glucose
does exercise alone control blood glucose
no
what is a major concern in exercise with type 1 diabetics
hypoglycemia during exercise is a major concern and may result in insulin shock
how to avoid hypoglycemia in type 1 diabetics during exercise
a regular exercise schedule lowers the odds of exercise induced hypoglycemia
- intensity, frequency, and duration
-altering diet and insulin
-may require fine tuning
* all must be discussed with physician
exercise and type 1 diabetes: metabolic control
type 1 diabetics must have metabolic control over their fasting glucose before engaging in physical activity
- avoid exercise if fasting glucose > 300 mg/dl
- ingest CHO if glucose is <100 mg/dl
exercise and type 1 diabetes: blood glucose monitoring
monitor blood glucose before and after exercise
- identify needed changes in insulin or food intake
- learn how blood glucose responds to different types of exercise
exercise and type 1 diabetes: insulin injection site
should be away from the working muscle to prevent increased rate of uptake in that muscle and hypoglycemia in that area
exercise and type 2 diabetes: primary treatment
exercise is the primary treatment as opposed to insulin
- helps treat obesity
- helps control blood glucose and reduce insulin resistance
- helps treat CVD risk factors
what may eliminate the need for diabetic drug treatments
combination of diet and exercise
once sedentary individuals (type 2 diabetics) have been trained why would they need to adjust their medication
to prevent hypoglycemia during exercise
- if type 2 and inject same amount of insulin and exercise= double response and bring in way too much glucose = hypoglycemia
asthma
a respiratory problem characterized by shortness of breath and a wheezing sound due to vasoconstriction of bronchioles
asthma is due to
contraction of smooth muscle of airways
swelling of mucosal cells
hyper secretion of mucus (increased mucus in airways)
how is asthma diagnosed
using pulmonary function testing (PFT)
PFT looks for 2 things when diagnosing asthma
1) vital capacity
2) Forced expiratory volume (FEV1)
vital capacity
maximal volume of air expelled after max inhalation
- keep breathing out till you cant anymore
forced expiratory volume (FEV1)
volume of air expired in 1 second during maximal expiration
after VC, breathe out as forcefully as you can and how much air you were able to push out in 1 second is FEV1
triggers of asthma attacks
allergens (dust, pollutants)
exercise
stress
once exposed to a trigger, what is the response of an asthma attack
plasma cells produce IgE antibodies which attach to mast cells lining bronchial tubes.
Mast cell then releases inflammatory mediators that results in fluid production and vasoconstriction
EIA (exercise induced asthma) is more common in
asthmatics but can occur in not asthmatics
EIA is caused by
repeated cooling and drying of respiratory tract which triggers the release of chemical mediators and airway narrowing
does EIA impair performance
not if medically controlled
how is EIA diagnosed
strenuous running at 80-95% HR max
then do a PFT to see if FEV has dropped more than 10 %
if it did drop, that is a strong indication that you’ve had vasoconstriction or narrowing of airways
means you aren’t able to move air out as easily leading to EIA
what sport does not show pulmonary function changes in asthmatics
swimming- don’t have decrease in FEV because mostly breathing in humid air so have no drying of airways = no EIA
how to reduce the chance of EIA attack
warm up (15 min at 60% of VO2 max)
perform short duration exercise
use a face mask in cold weather to help warm air as it comes in
treatment of EIA
beta-2 agonist in case of attack during exercise
other medications to prevent attack to cause relaxation of smooth muscle and vasodilation to open airways
does INHALED beta-2 agonists improve performance
no - only treats vasoconstriction
does INGESTED salbutamol (b2-agonist) improve performance
yes- improves strength, aerobic power, and endurance at 10-20x inhaled dose
normal BP
sBP < 120
dBP <80
elevated BP
sBP 120-129
dBP <80
hypertension stage 1
sBP 130-139
OR
dBP 80-90
hypertension stage 2
sBP >140
OR
dBP >90
prevalence of hypertension with increased age
increased
why is hypertension known as the silent killer
hypertension damages the endothelium , which predisposed the individual to atherosclerosis
increased afterload on the heart caused by hypertension may lead to LVR hypertrophy and is important cause of heart failure
hypertension txt
non-pharmacological approaches for mild or borderline hypertension
- lose weight if overweight
- limit alcohol intake
- reduce sodium intake
- eat healthy
- stop smoking
- exercise
exercise for hypertension
frequency: aerobic training on most/all days of week
intensity: moderate
duration: 30 to 60 min
mode: aerobic exercise supplemented by resistance training
effects of age on strength
strength increases as muscle mass increases with age
when does strength peak in men and women
~ 20 years women
~ 20-30 years men
the extent of muscular development depends on
relative maturation of nervous system
physiological responses to acute exercise: thermoregulation in children
children have increased SA:mass ratio
greater conductive heat loss, gain
less evaporative heat loss (decreased sweat)
slower heat acclimation
CV function in children in response to acute exercise: BP
resting and submaximal BP is lower than in adults because they have smaller hearts and lower peripheral resistance during exercise
children response to acute exercise on HR
higher HR which almost compensates for low SV
children response to acute exercise on SV
lower SV due to having smaller heart and lower blood volume
children response to acute exercise on Q
slightly lower Q than an adult
children response to acute exercise on (a-v)O2 difference
increases to further compensate
higher than men on graph
cardiorespiratory changes with age permit greater delivery of
O2
absolute VO2 max response to acute exercise as we age
increases with age in both boys and girls
relative VO2 max effects with acute exercise as we age in boys and girls
relative VO2 max stays steady with age in boys
relative VO2 max decreases with age in girls
lung function as we age in response to acute exercise
lung volume increases as we age
peak flow rates increase with age (increased muscle mass around respiratory muscles = easier to move air)
who has a worse exercise economy: adult or children
children have a worse economy- childs O2 consumption per kg is greater than adults
consume more O2= worse economy
with age, skills improve, stride lengthens
endurance running pace as we age
increases with age purely as a result of economy of effort
occurs regarless of VO2max changes, training status
anaerobic performance in children vs adults
children have limited anaerobic performance compared to adults (dont have enough muscle mass so it is harder for them to produce more power and less muscle = less glycogen= less enzyme = less production of byproducts
why do children have a lower anaerobic performance compared to adults
less muscle glycogen
less glycolytic enzyme activity
lower blood lactate
ATP-PCr stores in children vs adults
similar
weight lifting in children
is safe and beneficial
- injuries can be avoided by attention to proper technique as exercise can promote muscular strength and bone density
how to increase BMD in children
weight bearing exercises and sports
effects of aerobic training in children
improvement in VO2max similar to adults and performance increases due to improved running economy (longer legs = more economical)
anaerobic training in children leads to
higher resting PCr, ATP, glycogen
higher PFK activity
higher max blood lactate
- same in adults
physical activity patterns among youth
physical activity patterns established in childhood carry into adulthood
intervention strategies aimed at getting children more active have been mostly ineffective
early specialization in one sport reduces fun physical activities = reduced lifelong physical activity
what is sudden cardiac death in young atheletes due to
very rare
due to congenital heart defects, not exercise (abnormal, lethal heart rhythms
* a medical exam can identify those at risk
female vs male responses to training
females are similar to males
exception: thermoregulation is impaired during luteal phase (increase core temp) of menstrual cycle
concerns for female athletes
exercise and the menstrual cycle
eating disorders
BMD
exercise during pregnancy
athletic amenorrhea
cessation of menstruation
potential causes of athletic amenorrhea
1) amount of training
2) psychological stress
3) low EA
increased miles of training effects on amenorrhea
increases risk
training and menstruation
no reason to limit training during menstruation
*only limitation may be dysmenorrhea due to painful menstruation due to prostaglandins
prostaglandins
released in uterus and cause contractions = painful periods and may limit training capabilities during menstruation
anorexia nervosa
extreme steps to reduce body weight via starvation, exercise, laxative use
results in : effective weight loss, amenorrhea, death
bulimia
pattern of overeating (binging) followed by vomiting (purging)
results in : damage to teeth and esophagus
warning signs for anorexia
rapid weight loss
mood swings
excessive exercise
wearing baggy clothes
preoccupation w food/calories/weight
avoid food related activities
warning signs for bulimia
noticeable weight loss
depressive moods
excessive concern about weight
strict dieting followed by binges
increasing criticism of body
bathroom visits after meals
osteoporosis
loss of bone mineral content caused by estrogen deficiency due to amenorrhea and inadequate Ca2+ intake due to eating disorders
runners vs untrained women: bone mineral content
female runners have a higher bone mineral content than untrained females
female athlete triad
low Ea leads to menstrual dysfunction and low BMD
menstrual dysfunction leads to low BMD
RED-S
relative energy deficiency in sports
RED-S can be caused by psychological symptoms
energy availability calculation
EA: (energy intake - EE)/FFM
treatment of RED-S
primary objective is to increase EA by increasing energy intake, reducing EE (training volume) or a combination of both
*athletes practicing restrictive eating behaviors should receive nutritional counseling and psychotherapy
reasons females are at higher risk of knee injury
fluctuation in hormones during menstrual cycle
knee anatomy
dynamic neuromuscular imbalance
recovery from RED-s
recovery of energy status in days or weeks
then recovery of menstrual status in months
lastly recovery of BMD in years
why do fluctuation in hormones during menstrual cycle lead to increased risk of knee injury in females
may compromise ACL strength and or proprioceptor feedback
risk of knee injury in female athletes
female athletes are at a higher risk of certain knee injuries compared to men
3.5x higher risk of non-contact ACL injury
why does knee anatomy increase risk of knee injury in females
may be due to greater joint laxity
why does dynamic neuromuscular imbalance increase risk of knee injury in females
imbalanced strength, proprioception, and landing biomechanics
major adaptions to pregnancy
increases in plasma volume, Q, SV, HR
increase in tidal volume and minute ventilation
risk of regular endurance exercise during pregnancy
regular endurance exercise poses little risk to the fetus and is beneficial for the mother due to reduced risk of developing gestational diabetes and preeclampsia
- should consult with doctor prior to exercise due to absolute and relative contraindications
effects of training while pregnant on absolute VO2 max
increased or maintained
why does a combination of training and pregnancy result in a greater adaptation than training alone
due to increase in plasma volume during pregnancy
exercise recommendations for pregnant women
follow ACSM/CDC recommendation which is 30 min/day of moderate intensity activity on most/preferably all days
intensity of exercise for pregnant women can be determined by measuring
RPE 12-14
HR = may not be best method
“talk test”
what should you monitor while a pregnant women is exercising
temperature
hydration
intensity and volume
why is it important to monitor temperature with exercise in pregnant women
to prevent hyperthermia
limit body temp increase <1.5 C
aquatic exercise is recommended
maintaining adequate hydration with exercise in pregnant women
consume fluids at regular intervals (every 15 min)
monitor fluid balance by measuring body weight
when would you want to reduce training intensity and volume in pregnant women
as pregnancy advances due to regular examinations by physician
older adult exercise trends
many more older adults are exercising today recreationally due to recreation, competition, more fit compared to older sedentary counterparts
endurance performance declines after age
60
as shown by 10,000 m running time
VO2 max as we age
declines by 1% each year after age 45
mechanisms for age related decline in endurance performance
aging causes:
decreases in HRmax, SV, and (a-v)O2 difference which all decrease VO2max
exercise economy and LT stay the same with aging
all these factors lead to decrease in endurance exercise performance
training effects on VO2 max as we age
training can slow but not prevent decline in VO2 max
height effects with age
height decreases with age
- starts at 35-40 years
- compression intervertebral discs
- poor posture
- later, osteopenia, osteoporosis
weight as we age
weight increases, then decreases
increases 25-45 years old due to decreased physical activity and high caloric intake
decreases 65+ years due to loss of body mass and decreased apetite
body fat content as we age
body fat content tends to increase
- active vs sedentary older adults vary
- older athletes decrease body fat content and central adiposity
FFM as we age
decreases starting around age 40
why does FFM decrease after 40 years old
decrease muscle and bone mass
sarcopenia (protein synthesis decreases)
due in part to lack of activity
decreased growth hormone, insulin-like growth factor 1
strength as we age
loss of strength as we age due to lower level of activity in older adults
also due to sarcopenia (loss of muscle mass)
sarcopenia causes
decrease in muscle size (type I and II)
decrease in # fibers (type I and II)
greater reduction in type II fibers with aging
reflexes as we age
slow with age
BUT exercise preserves reflex response time
active older people = young active people
motor unit activation as we age
decreases
- but exercise retains maximal recruitment of muscle
- some studies show decreased strength due to local muscle factors (not neural)
BMD as we age
decreases
bone resorption > bone synthesis
due to lack of weight bearing exercise
osteoporosis is most common in
women over 50 due to lack of estrogen
exercise for bone health
weight bearing activities 3-5 times per week
resistance exercise 2-3 times/week
moderate to high bone loading
30-60 min/day
weight bearing endurance activities
activities that involve jumping
resistance training
what type of training is most effective as we age
resistance training
* but the combination of resistance and balance training can reduce the risk of falls
