objectives Flashcards
(83 cards)
difference between:
aerobic and anaerobic metabolism
Anaerobic:
- NO oxygen
- only carbohydrate (glucose)
- occurs in cytoplasm
- by product = lactic acid
- yields +2ATP per molecule of glucose
-* fast twitch fibers*
Aerobic:
- YES oxygen
- utilizes carbohydrates, fats, proteins
- occurs in mitochondria
- by products: water and CO2
- yields +36 ATP per molecule of glocuse
- slow twitch fibers
aerobic metabolism is approx 18x more efficient than anaerobic metabolism
VO2
gold standard
oxygen consumption = VO2 (mL O2 / kg^-1 * min^-1)
max VO2
peak VO2 (close to max but not threshold)
4-6% in persons with no known impairments
6-10% in persons with cardiopulmonary impairments
ways to measure VO2
VO2 = CO x a-v O2 difference
-or-
VO2 = volume of O2 entering lungs - volume of O2 leaving the lungs
Anaerobic Threshold, AT
not capable of performing work soley aerobically (start to perform work anaerobically so build up of lactic acid)
AT usually ~55% of max VO2
with training, increases more than 55%
with detraining, decreases less than 55%
clinically occurs when exercising and having difficulty talking to another (begin hyperventilation) - metabolic acidosis is trying to compensate with a respiratory alkalosis.
relationship of VO2 to METs
1 MET = requirement of O2 of tissue of the body at rest
1 MET = 3.5 mLO2 / kg min
- 1 MET = the energy (oxygen) used by the body as you sit quietly, perhaps while talking on the phone or reading a book.
- the harder your body works during the activity, the higher the MET
mod-intensity = 3-6 METs
vigorours = >6 METS
factors affecting peak VO2
age
sex
genetics (mm fiber types)
body compensation
endurance training
various diseases that affect oxygen transport
submax text assumptions
- a steady state HR is obtained for each exercise work rate
- a max HR for a given age is uniform (220-age)
- mechanical efficiency (VO2 at a given work rate) is the same for everyone
- there is a linear relationship between HR and workload
- HR will vary depending on fitness level between subjects at any given workload.
this may nit be trye and it has been suggested that submax exercise testing underestimates VO2 max in the untrained and overestimates the trained
advantages of submax testing
safer
controlled pace (motivation not a factor)
not population specifc (no pacing advantage)
quick assessment
cost effective
do not need highly trained personnel
can do mass testing
no physcian supervision (if symptom or disease free)
disadvantges of submax testing
- VO2 max is not directly measured (error rate of 10-20%)
- not a measure of true maximal HR
- estimates the max HR using 220-age can vary by +- 15 bpm for individuals of the same age
advantages and disadvantages of Max testing
adv:
- accuracy
disadv:
- health risk
- time
- expense (metabolic cart)
- personnel (MD supervision)
examples of endurance/aerobic capacity testing
treadmill: most often used in US
- bruce
- mod. bruce
- balke
- naughton
symptom limited grades exercise testing
posssible contraindications for cardiovascular
**- recent MI (within 3-6 weeks); recent change in the resting EKG suggesting ischemia
- PE or pulmonary infarction <6 weeks **
- if recent DVT detected and pt is on anti-coagulation therapy, then withhold high intensity strength on that limb
- —appropriate on other limbs if 1 of the following criteria are met:
IVC (Inferior Vena Cava) filter placed
» 3-5 hours after first low molecular weight heparin (LMWH) - Examples: Factor Xa, Lovenox
» Coumadin (warfarin), if PTT is 2-3x normal and INR is 2-3
– Note: if patient is on anti-coagulation therapy, some feel high intensity strength
training is not contraindicated - myocarditis, endocarditis, pericarditis
- recent cerebral shunting or aneursysm coil (increase in BP is contraindicated)
- restinf HR <50 or > 100
- severe pulmonary HTN (MAP >55)
- severe and symptomatic aortic or valvular stenosis
(severe aortic stenosis >80mmHg difference between aorta and ventrcile; synconpe episodses) - fistula on UE for dialysis access
- uncontrolled HTN
- decompensated HF
- absent pulse in the limbs
- suspected or known aneuysm
contra indications with retinopathy
possible contraindications with cancer and exercise
- bone metastasis sites (concern for pathological fx)
- tumors in targeted strength training area
- medication side effects
possible contraindications for MSK and exercise
surgical precautions, possible contraindications
other medical conditions,possible contraindications
medications, possible precautions
MET level chart
vacuuming- 3.5
dancing-6.5
jogging-7
bicycling-8
running a 7 min mile-14
respiratory volumes
normal exercise response
when to stop exercise: cardiovascular
when to stop exercise: neurological, integumentary, pain
when to stop exercise: respiratory and endocrine/GI
