KINE 1020: Energy Metabolism, Rest and Exercise (PDF)

KINE 1020: ENERGY METABOLISM, REST AND EXERCISE Prof: Michael Riddell, PhD Wed Nov 13 2023  How is VO2 and VO2max measured? http://general.utpb.edu/...

KINE 1020: ENERGY METABOLISM, REST AND EXERCISE Prof: Michael Riddell, PhD Wed Nov 13 2023  How is VO2 and VO2max measured? http://general.utpb.edu/ FAC/eldridge_j/Kine636 0/Lab%20Unit%20html %20file/Content%20Dis play%20%20Laboratory %20Unit_files/kimonbik eveandvi.jpg want to know VO2 max to of life) - predict longevity (length VO2 measured bile for > - max on safety - using a treadmill is more accurate be more muscle is being used http://upload.wikimedia.org/wikipedia/commons/thumb/d/db/Ergospirometry_laborator y.jpg/220px-Ergospirometry_laboratory.jpg http://www.horsesandpeople.com.au/sites/defa http://general.utpb.edu/FAC/eldridge_j/Kine6360/Lab%20Un ult/files/images/articles/2010-articles- it%20html%20file/Content%20Display%20%20Laboratory% images/horse-mask.jpg  usedtoculae e may Calculating oxygen consumption (VO2) This can also be called “O2 f Fick’s Equation Cardiac output (O2 delivery) extraction” or “a-v O2 difference” lamount Oxygen extraction of oxygen consumed ratio by the tissues) I I VO2 (ml/min/kg) = HR (bpm) x SV (ml) x (CaO2 – CvO2) (ml / P ↑ T O2/100ml blood) arterioleoxygen works heart rate heart rate stroke volume - harder you , Content (how much vein oxygen content Oxygen's in arteries] Increases , cardiac output (now much oxygen is Increase oxygen consumption Heart rate= how fast O O2 extraction= how Stroke volume= how returning to the heart S , Loading… through the velns) Increase H your heart beats/min much oxygen your x muscle cells extract much blood your ↳ will eventually plateau e tr heart beats/beat y per unit of blood be your body can't o take any moreoxygen a g rt k e to improve Oxygen consumption e (taking It from bloodstream R - n and into the cell) train at V , E Mitochondria e ol oxygen delivery xt to other cells Exercise intensity u Exercise intensity Exercise intensity Y r HR · SV = cardiac output (watts, calories, m (watts, calories, (watts, calories, a VO2, RPE) VO2, RPE)e VO2, RPE) ct io n VO2= “volume or amount of oxygen taken up and utilized by the body for energy metabolism” https://www.youtube.com/watch?app=desktop&v=yosN0b8fEL8  VO2 increases with exercise workload I - know vOz max for longevity , (energturned) and the shows the oxygen consumed don't need oxygen energy expenditure, # to 1 L O2 = 5 kcal amount acc needed to sustain the - 1 for the first few contraction movement (diff in Oxygen demand Work compare to other athletes (how VO2 and supply) fast you are of exercise ↳ phosphocreative gets bOxygen Deficit -heart rate : 220- your age used instead Work VO2 energy needed ↓ Work VO2 agen ( can consumed see O oxygen consumption moderate oxygen deficit Is less than energy needed intensity exercise Heavy intensity ↳ initial exercise the body cannot (jogging) exercise (running) during , Low intensity - more intense the exercise, supply oxygen fast enough to the muscles exercise (e.g. Oxygen Debt the greater the deficit is the I will use phosphocreatine Instead) , so oxygen walking) (breathing hard , catching consumption is not equal to energy demand up on oxygen lust In the beginning even though exercise is stopped leading to oxygen deficit · The oxygen uptake is a little sluggish to rise but eventually reaches a steady state to meet the energy demands using aerobic metabolism This process takes time (called the O2 deficit because the work is still getting done). Where does the ‘extra’ energy come from??  What happens with exercise? would have to deliver - How do we get more O2 consumption as the exercise more blood rich gets harder and harder??? with oxygen Oxygen Deficit Fick’s Equation VO2 VO2 = Q x (CaO2 – Work Loading… CvO2) HR x SV O2 extraction Oxygen Debt O2 delivery Optimal situation would be that you deliver more blood rich with oxygen and extract a greater proportion of the oxygen VO2max testing - VOz keeps can't on anymore increasing (VO2 max) until and it will plateau no more oxygen consumption continue to exercise without can VOz max - ( last oxygen be it is non-oxidative energy luse phosphocreative , which will 30s-1 minute and then you stop) O  What is a MET? 1 MET = 3.5 ml O2/kg/min Amount of energy you use at rest. Marker of exercise intensity MET normalizes to our size - so convert MET to energy you can expenditure by multiplying It by 35. http://en.wikipedia.org/wiki/File:Indirect_calorimetry_laboratory_with_canopy_hood.jpg  VO2 values for various activities Activity METs VO2 (ml/kg/min) Exercise Bicycling, 12-13.9 mph, moderate effort 8.0 28.0 Bicycling, 16-19 mph, vigorous effort 12.0 42.0 EX. to Walking, 2.0 mph 2.5 8.8 METS needed - 10 run Walking, 5.0 mph 8.0 28.0 Emph Running, 6mph 10.0 35.0 - used to understand possible/ Running up stairs 15.0 52.5 what tasies are perscribe appropriate exercise Sports METs given someone's Tennis, Doubles Play 5.0 17.5 Soccer 10.0 35.0 Golf, walking and carrying clubs 4.5 15.8 Downhill Skiing, moderate effort 6.0 21.0 Cross-country ski, 40-4.9 mph, moderate effort 8.0 28.0 Household Carrying small children 3.0 10.5 Vacuuming or Mopping 3.5 12.3 Ainsworth BE, Haskell WL, Whitt MC, Irwin ML, Swartz AM, Strath SJ, O'Brien WL, Bassett DR, Jr., Schmitz KH, Emplaincourt PO, et al: Compendium of physical activities: an update of activity codes and MET intensities. Med Sci Sports Exerc 2000, 32:S498-504. http://ezproxy.library.yorku.ca/login?url=http://ovidsp.ovid.com/ovidweb.cgi? A remember Why is VO2max important? - know vOz max for longevity , After the age of energy expenditure, # to about 40 years, compare to other athletes (how VO2 required for Various Activities you lose 5-10% of fast you are) your fitness every 60 10 years or so 50 VO2 (ml/kg/min) 40 30 20 10 0 Ca Ca Go Va Li 20 20 60 60 M Ba gh ow cu yM yW yM yW rry rry lf kin tP in um en en g Gr Gr om om gL lay in oc oc en en ing aw g er er n ies ies wi th Up Ch sta ild irs re n Poor Average Excellent  VO2 MAX VO2= cardiac output x O2extraction running up a hill running VO2 walking up a hill walking rest Workload  VO2max and Age 80 Women1 Endurance-trained women VO2max (ml/kg/min) 60 Active women Sedentary women - on average have a lower 40 - can measure how long you can live VO2 may 20 20 40 60 80 Aerobic Capacity is Age (years) Loading… the Best Metric of 80 VO2max and Age Men2 Endurance-trained men Active men Aerobic VO2max (ml/kg/min) Sedentary men 60 Prof R (Cardiorespiratory) 40 20 Fitness 20 40 60 Age (years) 80 What happens as you Fitzgerald MD, Tanaka H, Tran ZV, Seals DR. Age-related declines in maximal aerobic capacity in regularly exercising vs. sedentary women: a meta-analysis. J Appl Physiol (1985). 1997 Jul;83(1):160-5; Wilson TM, Tanaka H. Meta-analysis of the age-associated decline in maximal aerobic capacity in men: relation to training status. Am J Physiol Heart Circ Physiol. 2000 Mar;278(3):H829-34.; Pimentel AE, Gentile CL, Tanaka H, Seals DR, Gates PE. Greater rate of decline in maximal aerobic capacity with age in endurance-trained than in sedentary men. J Appl Physiol (1985). 2003 Jun;94(6):2406-13. age? - futs proteins carbs , , are burned for energy - don't need to remember graph https://www.mysportscience.com/post/how-sugar-helps-with-energy-supply What fuels do we have in our body and “burn” when we exercise Carbohydrate - three sources are used – Muscle Glycogen 350g (1400 kcal) to give energy if you haven't eaten , – Liver Glycogen 60g (240 kcal) - energy Is taken from the – Plasma glucose 10g (40 kcal) muscles Protein – Whole body (24,000 kcal) Fat – Muscle 500g (3850 kcal) – Adipose tissue 14kg (107,800 kcal) Based on data from Young and Scrimshaw, 1971. The ratio of carbohydrate to fat utilization depends on the exercise intensity. The lower the relative exercise intensity the greater the proportion of fat you burn RER is the respiratory exchange ratio RER= VCO2/VO2 - to find how much fat is burned, find the ratio between oxygen consumption Values represent and carbon dioxide production what the body is (t) using as fuel Values range from 0.7 (all fat) to 1.0 (all carbohydrate) Note: the overall energy expenditure (calories) is increasing as the exercise intensity increases so looking at percent oxidation of a fuel can be misleading…  Fat is a great fuel for rest and low intensity exercise, but carbs are “king” for high intensity work proportion of of proportion energy for energy for fat ↓ # carbs substratea is now quick - - makes high levels of ATrquicy/Instantly but is not a lot there J types of carbs - slowest in producing energy (ATP) Don’t memorize the numbers… just Note: the overall energy expenditure (calories) is remember that ATP production rates are faster with PC and carbs than with fat increasing as the exercise intensity increases so looking at percent oxidation of a fuel can be misleading…  The amount “grams” of fat use also depends on the exercise intensity 50% - to burn the most fat , train at graph is not accurate - sinceIt shows the most fat is burned at rest I proves that fat burned depends on intensity) While % fat oxidation is highest at rest, the overall energy expenditure (kcal, VO2) is low. So, the highest absolute rate of fat oxidation in grams per minute is NOT at rest but more like at about 55% of your maximal aerobic capacity. This is because your energy expenditure in kcals/min increases the harder you exercise. But at some point, fat oxidation is overtaken by carbohydrate oxidation (since carb oxidation can generate ATP Riddell MC, et al., J Appl Physiol. 2008 Aug;105(2):742-8. at a faster rate…)  glycogengetthere To help understand this graphic, visualize yourself starting at a slow walking speed and then you start going faster and faster until you are at your maximal running speed (VO2max) https://www.mysportscience.com/post/the-myth-of-switching-to-fat-metabolism  walling > - jugging -- running To help understand this graphic, visualize yourself starting at a slow walking speed and then you start going faster and faster until you https://www.mysportscience.com/post/2015/03/18/what-is-fatmax are at your maximal running speed (V02max)  - women do better than men in long-distance swimming To help understand this graphic, visualize a man and a women start at a slow walking speed and then gradually go faster and faster until they both reach 100% VO2max https://www.mysportscience.com/post/2017/10/10/women-are-better-fat-burners-than-men  What about fuel metabolism if the exercise intensity is fixed but the duration increases? opere The fat comes in two main forms… Muscle lipids and plasma non- esterified free fatty acids working longer not - Instead of making exercise harder , (NEFA) from our harder workout at constant pace fat cells a The longer you blend of fuels used when exercising exercise, the - Riddell et al (2020) Diabetologia DOI 10.1007/s00125-020-05183-8 instead of fueling shifting ↳ muscle the glycogen longer is you exercise not the main fuel used more fat you To help understand this graphic, visualize yourself cycling or brisk walking/jogging at a fixed burn! speed for 5 hours longer you fuel - being exercise , the more fatIs used as  Bottom Line If you want to burn your fat…. Exercise at a moderate intensity (50% VO2max, for a very LONG time [>2 hours]) – and do it often…