Fluent Essays

1. What energy system contributes to the ability to perform the WAnT? (Wingate anaerobic test) 2. How does one calculate the fatigue index, and what does it indicate? 3. How does the subject’s absolute peak power output compare with the norms presented in table 13.12 in the WAnT? 4. What is the importance of measuring power? What happens with power as you age? 5. Why is there a specific time frame following the warm up and before the start of the Wingate test? 6. Why are there differences in values in the variables between the countermovement jump and squat jump? 7. In your opinion, which test would be most beneficial for individuals during the Countermovement jump, the Vertec or Hawkins Force Plates? EXS 31600 Exercise Physiology Laboratory Lab 2 Objectives • Gain exposure to basic procedures used to evaluate anaerobic power and capacity • Examine the Wingate anaerobic test (WAnT) • Examine the Anaerobic step test • Examine the Standing long jump test • Examine other various work and power tests • Examine published norms for various anaerobic power tests Definitions • Anaerobic capacity: mean power output achieved during exercise bouts that last between 10 and 120 secs. Tests that assess anaerobic capacity typically stress the ATP-PCr and glycolytic energy systems. The term mean power is often used synonymously with anaerobic capacity • Anaerobic power: mean or peak power output in exercise lasting 10 secs or less. Anaerobic power is typically evaluated with tests that stress the phosphagen or ATP-PCr systems and require very high intensity for a short duration Definitions • Fatigue rate: rate of decline in performance; may be considered as the degree of power drop-off from the highest power output to the value at the end of the test, thus often calculated as percent change between these two values. • Mean anaerobic power: average power output achieved during a performance test that stresses the anaerobic energy supply mechanisms • Mean power: average power output achieved during a specified time interval or during a test Definitions • Peak anaerobic power: highest power output achieved during a test in which the anaerobic system is the primary supplier of energy (these tests typically last less than 10 sec) • Peak power: highest power output achieved during a test • Power: rate of doing work; calculated in terms of either work divided by time (power=work/time) or force multiplied by velocity (power=force x velocity) • Power endurance: ability to repetitively achieve high power outputs or to maintain a level of power output Definitions • Rate of Fatigue: rate that is represented as the degree of power drop-off during the test; also known as the fatigue index • Total work: product of mean power and time • Wingate anaerobic test (WAnT): test of anaerobic power and capacityperformed on a cycle ergometer that typically lasts 30 sec and uses a resistance equal to 0.075 kp· kg-1 body mass • Force plate: device that measures ground reaction forces; often considered the gold standard when evaluating vertical jump performance Background • Assessment of anaerobic fitness is an important part of the overall assessment of physical capacity for both athletes and clinical patients • Expressing a high power output is a primary contributor to success in sporting activities • Anaerobic fitness may be related to the ability to undertake activities of daily living • A loss in power-generating capacity can lead to a decreased ability to perform simple tasks of daily life Background • Testing is important to improve an individual’s power • Why? • Older adults experience a 3-4% rate of loss of muscle power per year • Necessary to raise from a chair or climb the stairs • Remain as independent in life as we can Work • Work = force x distance • In SI units: • Work (J) = force (N) x distance (m) • Example: • Lifting a 10 kg weight up a distance of 2 m • 1 kg = 9.81 N, so 10 kg = 98.1 N • 1 N•m = 1 J, so 196.2 N•m = 196.2 J • 98.1 N x 2 m = 196.2 N•m = 196.2 J Units for Work and Energy Power • Power = work ÷ time • In SI units: • Power (W) = work (J) ÷ time (s) • Example: • Performing 20,000 J of work in 60 s • 1 W = 1 J•s–1 • 20,000 J ÷ 60 s = 333.3 J•s–1 or 333.3 W Units for Power Measuring Work & Power • Ergometry • Measurement of work output • Ergometer • Device used to measure work • Bench step ergometer • Cycle ergometer • Treadmill Ergometers we will use… Bench step Treadmill Cycle ergometer General Bench Step • Advantages: • Inexpensive • Little space and noise • Disadvantages: • Difficult to obtain high intensities • Not suitable for all people (elderly, knee problems, etc.) • Factors for calculating work and power • Body weight of subject (Force) • Height of the step (Distance) • How fast you are stepping (Distance) • Depends on the test • How long you are stepping for (Distance) Anaerobic Step Test • Mainly utilizes the glycolytic pathway • Also receives ATP from phosphagen and aerobic system • Measure of mean anaerobic power • Only one leg is used • Can choose one which leg to perform on (preferred leg) Anaerobic Step Test Equipment • Bench (Step) • 40 cm (15.75 in) • Stopwatch • Calculator • Weight scale Measurements • Body mass • nearest tenth • Number of steps • Steps does not count if the leg does not straighten or if the back is bent • Duration of test • 1 minute • First upward movement • Call out every 15 s Anaerobic Step Test Preparation • 0 – 2:00 min • Walk in place at a moderate rate; lift thighs to 90° • 2:00 – 3:00 min • Stretch: (1) groin; (2) quadriceps; (3) calf • 3:00 – 5:00 min • Step up and down on a step using both legs in at a moderate pace • 5:00 – 7:00 min • Relief interval: Mild walking in place and/or stretching Anaerobic Step Test Recovery • Working leg (preferred leg) is likely to be very weak at the end of this test, perhaps causing a few “buckled” walking steps • Working leg (preferred leg) may experience DOMS • Active recovery immediately after the test • Walking • Jogging • Can perform static stretching if needed Anaerobic Step Test Calculations • Force • = Body mass (N) • Distance = Step height (m∙step-1) • Steps = # of steps • Total work (N∙m) = Mass x Step height x total # steps x 1.33 • Mean power (W) = Total work (N∙m)/ 60 (s) Anaerobic Step Test Example • Total work = [Force (N) x step ht (m) x # Steps * 1.33] • Body wt = 70 kg • 70 kg x 9.8067 N ∙ kg-1 = 686 N • Force = 686 N • Step height = 0.40 m • # Steps = 50 • Total work= [686 N x 0.40 m x 50 steps x 1.33] = 18,248 J Anaerobic Step Test Example • Absolute Mean Power = Total work / Time (s) • Body wt = 70 kg • 70 kg x 9.8067 N ∙ kg-1 = 686 N • Force = 686 N • Step height = 0.40 m • # Steps = 50 • Time = 60 s • Absolute Mean Power = 18,248 J / 60 s = 304 W Anaerobic Step Test Example • Relative Mean Power = Absolute mean power / mass (kg) • Relative Mean Power = 304 W / 70 kg = 4.34 Anaerobic Step Test Classification To find kJ. Divide J by 1,000 Calculations – Peak and Lowest Anaerobic Power • Peak (highest) • First 5 s (0-5 s) of the test (assumed to be the highest number of steps) • Lowest • Last 5 s (55-60 s) of the test (assumed to be the lowest number of steps) • Peak anaerobic power (W) = [Force (N) x Step ht (m) x # Steps x 1.33 ] / 5 s • [686 N x 0.40 m x 9 x 1.33] / 5 s = 657 W • Lowest anaerobic power (W) = [Force (N) x Step ht (m) x # Steps x 1.33 ] / 5 s • [686 N x 0.40 m x 4 x 1.33] / 5 s = 292 W Anaerobic Step Test • Subject may fall into different category for relative mean power • Due to body weight • Anaerobic step test can be used as an alternative to the Wingate cycling test Wingate Anaerobic Test (WAnT) • Most popular anaerobic cycling power test • Developed at the Wingate Institute in Israel • Hence the “Wingate” Name • Monark cycle ergometer • “Basket-style” – force instantly applied • “Pendulum-style” – turning the knob to adjust force • We’ll be using the basket-style version for the lab • WAnT is performed for 30 sec against 0.075 kp · kg-1 • The test is designed to test anaerobic performance capacity Wingate Anaerobic Test (WAnT) • Requires energy production from the ATP-PCr and glycolytic energy systems • 60%-85% • First 3 – 15 sec of WAnT • ATP-PCr system • 15 – 30 sec of WAnT • Glycolytic system • Can be used to determine peak anaerobic power, lowest anaerobic power output, mean anaerobic power, total work, and rate of fatigue Wingate Anaerobic Test (WAnT) • Peak anaerobic power • Highest mechanical power generated during the WAnT • Typically occurs in the first 5 sec • Time intervals for calculation • 3 or 5 sec intervals • We’ll be using 5 sec intervals for the lab • Flywheel • Used to help calculate Peak anaerobic power • Flywheel is 1.62 m in circumference • 3.7 rotations per pedal revolution • Produces a total distance of 6 m per revolution Wingate Anaerobic Test (WAnT) Warm- up • Warm-up • 5 min of low-moderate intensity pedaling around 60-70 rpm • Interspersed by 2-5 all-out sprints of 4-6 sec. • Recovery interval • 2-5 min rest after warm up (rest or minimal pedaling) • No < 2 min and no > 5 min of rest • Why? • 2 min provides adequate recovery time from any possible fatigue that the subject may have incurred during the warm-up • 5 min still retains muscle temperature and blood flow Wingate Anaerobic Test (WAnT) Warm- up • Recovery interval • 2-5 min rest after warm up (rest or minimal pedaling) • No < 2 min and no > 5 min of rest • Why? • 2 min provides adequate recovery time from any possible fatigue that the subject may have incurred during the warm-up • 5 min still retains muscle temperature and blood flow Wingate Anaerobic Test (WAnT) Example • Force (kg) = body weight (kg) x 0.075 kp · kg-1 • Force (kg) = 70 kg * 0.075 = 5.25 • Force (N) = force setting (kg) * 9.8067 • 5.25 x 9.8067 = 51 N Wingate Anaerobic Test (WAnT) Example • Peak Anaerobic Power (W) = [Force (N) x #Revolutions x 6 m∙rev-1] / 5s • = [51 N x 10 rev x 6 m∙rev-1]/ 5s = 612 W • Relative peak anaerobic power • Peak anaerobic power (w) / body weight (kg) • 612 W / 70 kg = 8.7 W∙kg-1 Wingate Anaerobic Test (WAnT) Example • Total work • Work (J) = [force (N) x # Revolutions x 6 m∙rev-1] • 51 N x 10 rev x 6 m∙rev-1 = 3,060 J • Relative work = Total work (J) / Weight (kg) • = 3,060 J / 70 kg = 43.71 Wingate Anaerobic Test (WAnT) Example • Mean Power output (W) = Total work (J) / Time (s) • = 3,060 / 30 s = 102 W • Relative mean power = Mean power output (W) / Weight (kg) • = 102 W / 70 kg = 1.46 Wingate Anaerobic Test (WAnT) Example • Rate of fatigue is also known as the fatigue index • Represented as the degree of power drop-off during the test • A fatigue rate of ≥40% can be found from the first 5 sec (peak power ) to the last 5 sec (lowest power) • The higher the fatigue index, the less fit the individual is • Fatigue Index (%) 𝑃𝑒𝑎𝑘 𝐴𝑛𝑎𝑒𝑟𝑜𝑏𝑖𝑐 𝑃𝑜𝑤𝑒𝑟 − 𝐿𝑜𝑤𝑒𝑠𝑡 𝑃𝑒𝑎𝑘 𝑉𝑎𝑙𝑢𝑒 𝑃𝑒𝑎𝑘 𝐴𝑛𝑎𝑒𝑟𝑜𝑏𝑖𝑐 𝑃𝑜𝑤𝑒𝑟 𝑥 100 Wingate Anaerobic Test (WAnT) Example • Important to examine relative power outputs • Need to consider body mass • Lowest anaerobic power is the lowest power output achieved during any individuals 5 sec interval during the WAnT • Usually occurs during the last 5 sec of the test • Used in calculating the fatigue index WAnT Classification Jumping Performance • Jumping performance is one of the most popular field tests used to assess anaerobic power in athletic populations • Jumping ability has also been shown to differentiate between level of play and playing abilities in American football and soccer players • Vertical jump • Countermovement • Static • Standing Long jump Jumping Performance • Countermovement jump requires the athlete to start in a standing position, drop into a squat position, and then immediately jump as high as possible Phases of the Countermovement Jump • 6 key sections of a standard CMJ • Quiet Phase • Unweighting Phase • Braking Phase • Propulsive Phase • Flight Phase • Landing Phase https://www.hawkindynamics.com/blog/the-cmj-best-practices-and-what-to-look-for https://www.hawkindynamics.com/blog/the-cmj-best-practices-and-what-to-look-for Jumping Performance • Static vertical jump, or squat jump, requires the athlete to squat with the tops of the thighs parallel to the floor, holding this position during a countdown (“3,2,1, jump”), and then jump as high and as fast as possible Hawkin Dynamics Force Plates • Force plates are tools that measure ground reaction forces during walking, jumping, or any type of movement. • Use sensors called load cells to measure these forces and the corresponding values. • With the data measured by the force plates, we can measure a number of things including: • Velocity (m/s) • Power (Watts) • Displacement (Meters) • Flight time (time between takeoff from the force plate and landing n it during the jump) • Temporal parameters (seconds) • Left/Right Asymmetry (for bilateral systems) Standing Long Jump Test • Alternative power test to the vertical jump test • During this test, the subject places both feet behind a taped line • Without any preparatory steps, the subject swings the arms backward and propels themselves forward. • The subject must stick the landing • Trial is discarded if the client falls forward • The jump distance is measured from the starting line to the back of the heel of the foot that landed closest to the starting line What can impact results for jumping performance? • Movement during the quiet phase • Hand placement • Above head • On hips • Arm swing • Lack on motivation • Minimal effort during jump Procedures for Lab 2 Anaerobic Step Test Procedure • 1-minute • Stepper is standing alongside the bench • The working leg (preferred leg) rests on top of the step • The free leg does not touch the step • The working leg (preferred leg) raises the body to the top of the step • Remains on for duration of testing • The foot of the free leg can push off when it contacts the floor • Legs and back must be straight throughout the test • Arms can be used for balance but not cannot be pumped vigorously during the test • Cadence is one-two count (one – up; two – down) WAnT Test Procedures • Step 1: Set up the cycle ergometer and check to see if it is in working order • Step 2: Gather basic data (e.g., age, height, weight) for the individual. Have the subject put on his or her shoes. • Step 3: Calculate the prescribed load of the subject and record this load on the data sheet • Step 4: Fit the cycle ergometer to the subject so that while the subject is seated on the bike, the extended leg has a slight bend (5° - 15°) • Step 5: Explain the test protocol to the subject. Emphasize that this is an all-out effort lasting 30 s WAnT Test Procedures • Step 6: Have the subject perform the standardized warm-up and recovery outlined • Step 7: Initiate the test with the subject pedaling against one- third of the prescribed load at 20 to 50 rev · min for 5 to 10 s. • Step 8: Instruct the subject to increase the pedaling rate to maximum. Instruct the force setter to apply the load and the timer to start the timer and yell “Go” when the subject reaches a maximal pedaling rate. • Step 9: Upon hearing the “Go” command, the counter should begin counting pedal revolutions (This step is not performed if you are using a computerized system) WAnT Test Procedures • Step 10: The counter should tell the recorder the total number of revolutions completed at the end of each 5 s time interval during the test (i.e., at 5, 10, 15..) • Step 11: At the 30 s mark, the timer yells “Stop” and the force setter reduces the load so that the subject can pedal at 25 to 100 W for 2 to 5 min or until recovered. At this time, the counter tells the recorder the number of total revolutions completed for the total 30 s ride. The recorder then determines the number of revolutions completed during each 5 s segment of the test • Step 12: Convert the prescribed load to newtons by multiplying the load by 9.80665. Calculate the power output from the total number of revolutions, the distance the flywheel travels per rotation (6 m if using a Monark), and the duration of the interval. Calculate the power output for each time interval, and record it in the appropriate location on the individual data sheet. • Step 13: Divide the power output calculated for each time interval by body weight to determine a relative time interval. Record these values on the individual data sheet. WAnT Test Procedures • Step 14: Determine the absolute and relative peak power outputs. Record these values on the individual data sheet. • Step 15: Calculate the absolute and relative work accomplished during the 30 s interval. Record these values on the individual data sheet. • Step 16: Calculate the absolute and relative mean power outputs accomplished during the 30 s test. Record these values on the individual data sheet. • Step 17: Determine the absolute lowest power output and record this value on the individual data sheet. • Step 18: Calculate the fatigue index using the equation supplied on the individual data sheet. Countermovement Jump Procedure • For the CMJ, the participant MUST keep their hands on their hips at all times during the movement. • Begin the test by cueing the participant in the following ways for EVERY TEST: • “Hands on the hips. Ready” • The participant shall give a slight bend in their knees and hips. This is not a complete squat, just a slight change in joint angle. • After you say “ready” and the participant is in the pre-jump position, press the play button on the tablet. • There will be a brief period of time, termed the quiet phase, followed by a beep. • Once the tablet beeps, instruct the participant to jump by saying “Jump”. • The participant will drop straight down with a squatting motion and then immediately back up to take off. Make sure that they land on the plates after the jump. • Once the participant lands, instruct them to hold the landing position by saying “Stick” • After the tablet shows the results, you can instruct the participant to “Recover” and then begin the timer for the next set. Squat Jump Procedure • For the jump squat, the participant shall keep their hands on their hips at all times during the movement. • Begin the test by cueing the participant in the following ways for EVERY TEST: • “Hands on the hips. Ready” • The participant shall move into a full static squat and hold still before jumping • After you say “ready” and the participant is in the pre-jump squat position, press the play button on the tablet. • There will be a brief period of time, termed the quiet phase, followed by a beep. • Once the tablet beeps, instruct the participant to jump by saying “Jump”. • The participant should be sure not to drop anymore from the squat position but should only propel themselves straight up with as little countermovement as possible. • The participant must land on the plates for results to process. • Once the participant lands, instruct them to hold the landing position by saying “Stick” • After the tablet shows the results, you can instruct the participant to “Recover” and then begin the timer for the next set. Standing Long Jump Procedure • Place a 2- to -3-foot (0.6-0.9 m) length of tape on the floor to serve as a starting line • The subject stands with the toes just behind the starting line • The subject performs a countermovement and swings the arms and jumps forward as far as possible • The subject must land on their feet for the jump to be scored. Otherwise the trial is repeated • A marker is placed at the back edge of the subject’s rearmost heel, and the tape measure determines the distance between the starting line and the mark • The best of three trials is recorded to the nearest 0.5 inches or 1 cm In-Person Lab • Please wear appropriate clothing and shoes for testing • Athletic wear • No jeans • No sandals • Make sure to read each procedure thoroughly and have a good understanding • We will begin testing once the class starts