CV exercise physiology & outcome measures Flashcards
what is VO2 Max?
maximum amount of O2 a person can consume at max physical exertion
why is VO2 max so important?
- most widely recognized measure of cardiopulmonary fitness and aerobic endurance
- main prognostic indicator of cardiopulmonary morbidity and mortality
what is used to describe exercise intensity?
MET = metabolic equivalent of a task
1 MET = _____
- 1 MET equation?
amount of energy used for 1 minute of quiet rest
1 MET = 3.5 mL O2 x kg x min
direct correlation to VO2 Max
light exercise ~____ METs (washing dishes, cleaning)
vigorous exercise ~ ____ METs (climbing stairs)
2.5-2.8
8.0
what subjective scale is used often in the cardiovascular and pulmonary population where the patient perceives the intensity of exercise?
Rate of Perceived Exertion = RPE
what is the difference between max HR and resting HR? aka this is the amount of wiggle room you have to exert your patients
heart rate reserve = HRR
what are slow twitch fibers?
oxidative
aerobic metabolism: uses O2 + glucose to produce ATP
slows to fatigue
contracts slowly over longer period of timie
what are fast twitch fibers?
glycolytic
anaerobic metabolism: uses proteins + glucose to produce ATP with lactic acid byproduct
fatigues quickly
fast contractions for short amount of time
if you are working with a long distance runner, which muscle fibers are going to be working more?
slow twitch
if you are a sprinter athlete, which muscles are you primarily working?
fast twitch
1st ventilatory threshold (VT1):
using aerobic metabolism but with increased exercise you’re using less aerobic metabolism and increasing anaerobic metabolism
2nd ventilatory threshold (VT2):
body relies mostly on anaerobic metabolism, virtually no aerobic metabolism
which ventilatory threshold is considered the “walkie talkie” test?
1st - you can walk and talk without becoming exhausted
physiologically, what is happening:
– at VT1:
– between VT1 & VT2:
– at VT2:
– kidneys release HCO3 once blood lactate levels > 2
– kidneys now can’t keep up with the amount of lactate being produced. blood pH signals respiratory center in brainstem to increase breathing rate to “blow off” excess CO2
– increasing CO2 levels requires us to breathe faster where we can’t maintain a conversation
what’s a good way to monitor that we are keeping our patient in VT1?
engage in conversation as you’re walking with them - if talking and walking becomes difficult you are nearing VT2
if your patient is in VT1, what RPE rating does that correlate with?
11-13/14
what is the most important noninvasive procedure used in the diagnosis and management of patients with CAD?
graded exercise testing (GXT)
what is GXT?
systematically and progressively increasing O2 demand and evaluating the responses to increased demand
what are risk factors for needing exercise testing performed?
men > 45, women > 55
family history of heart attack or sudden death
smoking
sedentary lifestyle
obesity
hypertension
dyslipidemia
pre-diabetes
_____% of HRmax is considered low intensity exercise
_____% of HRmax is considered moderate intensity exercise
____% of HR max is considered vigorous intensity exercise
50-63%
64-76%
77-93%
assign the proper risk category for each of the following:
– asymptomatic, < 2 risk factors
– asymptomatic, >/= 2 risk factors
– symptomatic or known CV, pulmonary, renal or metabolic disease OR major S&S of CV, pulmonary, or metabolic disease
– low risk
– moderate risk
– high risk
a patient is considered low risk. are they required to perform GXT or have a medical exam done before exercising?
no
a patient is asymptomatic but has 4 risk factors for activity. should they have a medical exam or GXT assessed before exercise? what about MD supervision?
medical exam - no for moderate intensity exercise,
yes for vig. ex.
no MD supervision.
