Final Review 063008a(1).1

Final Review 063008a(1).1 - Cardiovascular HR; SV; Q...

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Unformatted text preview: Cardiovascular HR; SV; Q (definitions) Q = HR x SV Trained (limited by age) vs. untrained At rest, Q no difference Untrained 15 ­18 Trained HR use Max HR Ex. Int @ 70% 20 years old Age ­predicted: 200 x 0.7 = 140 (over ­estimated) Karvonen: THR = (max HR – RHR) x int. + RHR (RHR given) Always gives a higher heart rate; but brings value closer to actual value Eg RHR = 70 THR = (130 x 0.7) + 70 Blood pressure P = F (flow) x R (resistance) Syst – 90 ­150 (highest stand up; lowest lying down) Diast – 40 ­85 Rhythmic vs. resistive (valsalva) Rhythmic eg cycling: gradual rise in blood pressure; max syst = 200 mmHg? Resistive: vaslsa ­ elevate max 300 mmHg “cool down” – venous return  ­ Accessory muscle pump  ­ Keep blood coming back to heart Blood distribution 5 ­6 blood distribution; muscle get rel large supply Relative to size, kidney get the most Max exercise – redistribution of blood to active areas; 90% to skeletal muscles Oxygen consumption Submax SS VO2 (workload) – when VO2 is max No difference in SS btw trained and untrained same workload O2 req (SS x # min) O2 req – O2 consumed = O2 deficit Approach to SS for end trained; O2 deficit is smaller O2 deficit ~= O2 “debt” Smaller deficit shorter recovery/smaller O2 debt Max VO2 3 ways to express: L/min, mL O2/kg/min, mL O2/kg FFM/min Best compare individuals: mL O2/kg/min (b/c have to carry BW) Gender differences biggest discrepancy: L/min Smallest: mL O2/kg FFM/min M F Avg 45 38 Good 50 ­60 40 ­50 Excellent ~70 ~60 Out ~80 ­90 70 ­80 1 2 Max VO2 3.0 4.0 SS VO2 2.0 2.0 Int 2/3 = 67% 2/4 = 50% LT 80% 45% If only max / rel int given: Lower rel intensity more likely to prevail  ­ #2 If LT given: Int<LT #1 more likely to prevail Environmental Altitude – hyperbaric  ­ Colder  ­ Drier  ­ Decrease in air density: lighter and less resistance  ­ Increase in UV Exercise  ­ Decr. Air resistance Both horizontal and vertical movement Faster  ­ Decr. Gravity (?) Very mild effect of gravity  ­ Decr PO2 Offset aerobic improvement that could occur Beyond mile Swimming also affected Runners get more advantage than swimmers b/c no change in resistance in water Mountain sickness (>24 hours) 6000 ft 14000 ft almost everyone develop: can last more than 48 hours  ­ Headache (universal)  ­ Insomnia  ­ Decr. Food  ­ Restless Diseases associated with mountain sickness Pulmonary edema Cerebral edema? Acclimatization >= 48 hours EPO increases RBCs (EPO targets bone marrow)  ­ women has more difficulty ~7000 ft go down by ? 85% (acute) vs. 97% (acclimatized) Return to SL Natural blood doping No indication ppl will perform better at SL training at altitude Training at same level Getting better quality workout b/c higher intensity Lose weight, muscle mass Lack of ability to maintain intensity and decrease in food intake Calculation: 1000 m decrease to 0.9 1.0 ATM @ SL 1000m 0.9 ATM BP = 760 @ SL 1000m 760 x 0.9 Hyperbaric 10 m (33 ft) = 1.0 ATM 66/33 + 1 (for SL) = 3 1. P =1/V Ascends lungs expand 2. N2 narcosis ~ 90 ­150 ft Lean ppl are easier Commercial dive: replace N2 with He 3. Bends High pressure and time at pressure Bubbles form in tissues Decompress slowly ascend according to schedule Obese ppl are more likely to be bent 4. O2 toxicity ~10ATM (300 ft) PO2 ~= 1600 mmHg Temperature Homeotherm (can maintain core temp; not slave to environment) vs. poikilotherm (core temp dependent on ambient; not have to eat as much) ~80 F (cardiac fibrillation when rewarmed) 98.6 ~106 – 107 (beyond irreversible brain damage) Heat loss/Gain Main method of heat gain is metabolism Range 1 cal/min at rest; 20 cal/min at exercise 1. ***Radiation  ­ Temp diff of environment and body (gradient) Body Type: tall, thin have greater b/c high SA to mass ratio; get heat ot surface Also depending on blood supply Clothing color: light skin, light color clothing deflect rad Ambient temp 2. Convection: wind 3. Conduction: water 20x faster than air 4. Lung Evaporation: animals that don’t have sweat gland 5. ***Sweat  ­ Average sweat rate 1 ­2 L/hr (during exercise in warm climate)  ­ Max ~4 L/hr  ­ 1L = 580 cal  ­ Sweat must vaporize  ­ Ambient conditions are a factor  ­ If air saturated, sweat cannot vaporize  ­ RH >80%, sweat not vaporize  ­ If clothing that prevents from evaporating, eg rubber, plastic, artificial fibers, not allow moisture to penetrate, prevent loss of heat by perspiration  ­ Sweat (less solute) is hypotonic to plasma  ­ Plasma 3x NaCl relative to sweat Have to replace the Recommended water replacement 250 mL every 15 min 1L water ingestion per hour  ­ Plasma 5% of BW intracellular  ­ Interstitial 15%  ­ Intracellular 40%  ­ Water deficit primarily in intracellular (muscles) performance decrements  ­ 4% dehydrate strength decr. 30%  ­ 15 ­20% even after recovery Dehydration 1 L = 1 kg = 2.2 lbs 2% “thirst” 3 ­4% performance decrement Beyond: Heat stroke, coma and death Gastric emptying Ingest fluid orally Slows:  ­ High Osmolarity  ­ High Sugar  ­ Low pH GA vs. MSW 400mL intake 250 vs. 150 out GA will not empty out stomach very quickly However, GA did not inhibit performance for one hour Hypothalamas (thermostat of body) Temp of blood Heat retention: Vasoconstriction Shivering (incr. Metabolic rate by 2 ­3x) 98.6 F (37) Cold H2O High conducting effect of water 70F No problem 60F 5 ­6 hours 30F 15 ­20min Fat is 3x better than muscle? b/c avascularized Heat adaptation Climatization: Increase capacity to sweat Cold adaption: more psychological than physiological Sweat vasodilation ...
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This note was uploaded on 10/28/2010 for the course EXSC 205Lxg taught by Professor Girandola during the Spring '07 term at USC.

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