Effects of Aerobic Exercise - Class 6 Flashcards
pressor response
sympathetic nervous system from stimulation of myelinated and unmyelinated nerves in exercising muscles
physiological effects
pressor response
cardiac effects
net reduction in total peripheral resistance
increased CO and systolic BP
rapid changes in respiratory rate*
there is –> pressor response
generalized vasoconstriction in non exercising muscles
there is increased –> pressor response
myocardial contractility
heart rate
systolic BP
results in marked increase in CO
cardiac effects –> increase
frequency of SA node depolarization
force development of cardiac myofibers
SNS stimulation
cardiac effects –> decrease
vagal stimuli
net reduction in total peripheral resistance is d/t
locally mediated reduction in resistance of arterial bed of working muscle(s)
what is the decreased resistance caused by –> net reduction in total peripheral resistance
metabolites –> independent of ANS stimulation
veins of working and non-working muscle –> net reduction in total peripheral resistance
remained constricted
rapid changes in respiratory rate
even before initiation of exercise
alveolar respiration –> rapid changes in respiratory rate
increased up to 10-20 fold during intense exercise
–> to supply additional O2 needed and excrete excess CO2 produced by exercise
additional O2 to muscles
increased blood flow and oxygen extraction
increased oxygen extraction
decreased of PO2
CO2 production
decreased PO2 –> increased oxygen extraction
occurs secondary to use in working muscle(s)
CO2 production –> increased oxygen extraction
causes tissue to become acidotic
tissue temp increase –> causing a right shift and dissociating more O2
determinants of aerobic exercise program
frequency
intensity
frequency
no clear cut info on optimal frequency
general guidelines –> frequency
3-4 times a week
ACSM PA guidelines –> frequency
150 minutes of moderate intensity exercise activity every week
30 min 5 days a week
intensity
overload principle applies
when does conditioning response generally occur –> intensity
60-90% maximum HR
50-85% VO2 max
for healthy young individuals –> intensity
70% HR max
for deconditioned individuals –> intensity
50% HR max
in young healthy individuals
intensity can be determined in a variety of ways
determining intensity for a healthy young individual
maximum performs multistage stress test
extrapolated from max HR on submaximal test
220-age is less accurate estimate
determine target exercise HR
% range of estimated or measured HR max
karvonen equation
karvonen equation
Exercise HR = HR(rest) + 60-70% (HR max - HR rest)
how long should we exercise at 60-70% of HR max
20-30 min
lower intensity likely require
longer sessions
what would a deconditioned individual benefit from
multiple smaller sessions throughout the day
numerous exercise types
elicit stimulus and training response
what is most important –> elicit stimulus and training response
that large muscle groups are worked in rhythmic aerobic fashion
what needs to be planned –> elicit stimulus and training response
to meet needs and capacity of the pt
reversibility
occurs rapidly
when are reductions in work capacity measured
after 2 weeks of detraining
improvements will be lost
in several months
reversibility
amount required to maintain significantly less than required to improve
when are physiological responses seen
at rest
physiological responses (1)
decreased HR and BP
increased hemoglobin and blood volume
larger long volumes and diffusion capacities
muscle hypertrophy and increase capillary density
physiological responses (2)
increased number and size of mitochondria
increases engagement socially
decreases threat of associated pain
appropriately dosed exercise –> physiological responses
may elicit exercise induced hyperalgesia
majority of Americans ages 18-64
do not meet recommended activity guidelines
most of our pts
not regularly active
what should we recommend
easy movements
how should we disguise aerobic exercise
as a warm up
what should we educate
incorporation into everyday activities
make recommendations on
ways to begin increasing activity
stress it is not a 0 sum equation –> some is always better than none
what should we leverage
additional benefits of CV exercise
monitoriing progress/response
HR response
distance
work
RPE
HR recovery time
BP
