Assessment of Anaerobic & Aerobic Power

Transcription

1 Assessment of Anaerobic & Aerobic Power The most popular anaerobic cycling test is the Wingate Anaerobic test (WAnT), named after the university in Israel where it originated. The original test was designed for children but became popular for adults in the late 1970 s (Bar-Or et al., 1977). It fulfilled the need for a precisely measured anaerobic power test. Although most commonly used to test the legs, it can be used to test the arms. This anaerobic test can determine the performer s peak anaerobic power, average (mean) anaerobic power, total work and fatigue ratio (index). Peak power is based on the highest power level averaged over a 5-s period during the test, whereas mean power refers to the average power during the entire 30 s of the test. The total work represents the product of the number of pedal revolutions, accomplished and the force or resistance level during the 30-s period. The fatigue ratio measures the rate of power decrease from the point of peak anaerobic power to the finish of the test. Physiological Rationale for the WAnT This 30-s all-out test may be appropriately referred to as a power-endurance test because it is predominantly dependant upon the combination of the anaerobic pathway s powerful phosphagenic component and its enduring glycolytic component. Hence, the WAnT reflects both short-anaerobic fitness and long-anaerobic fitness, with the combination of the phosphagenic and glycolytic pathways representing estimates a much as 85% of the ATP production during the entire 30s of the Wingate Cycle Test. Equipment Cycle ergometer Computer w/ Sports medicine Industries computerized system Procedure 1) Obtain the subjects height and weight 2) Adjust the seat height so that the performer s knee is slightly bent when the ball of the foot is on the pedal. 3) Allow subject to pedal on the cycle for 2 minutes. 4) Enter performer s data into computer. The computer will provide the resistance setting; place the proper plate weights into the basket. 5) Ask performer to get back onto the cycle. Instruct them NOT to pedal! Secure feet with foot straps (Note: Tape may be needed). 6) Describe the over view of the test to the subject. a. EXAMPLE: This test is going to assess your body s anaerobic power. It only lasts 30-s, and feels like your riding this bike right up a hill. Now, when we start this test I want you to pedal as hard and as fast as you can, now I want you to remember that most people have the tendency to hold their breath. I will be cheering you on and reminding you to breathe. At the end of the 30-s bout I want you to continue to pedal, this will provide your body with a proper cool down. The resistance will be decreased upon the end of the session. Page 1

2 7) Establish a count down for the performer to start the test (e.g. 3, 2, 1, Start). Encouragement should be provided, that is if the performer wishes to have it given. 8) Record all data. Maximal Oxygen Consumption A test of aerobic fitness that truly qualifies as a lab test is the Maximal Oxygen Consumption (VO 2max ) Test. Although this test may involve a substantial anaerobic contribution to metabolism at the terminal portion of the test, it is primarily an aerobic test. Whereas the running and cycling tests attempt to predict aerobic power as accurately as possible, the VO 2max Test actually measures aerobic power. Various run/walk tests, for example, predict maximal oxygen consumption based on the relationship between maximal oxygen consumption and time or distance of running or walking; step tests and cycle tests estimate the maximal oxygen consumption based on the relationship between heart rate, oxygen consumption and power level. Because the VO 2max Test directly measures oxygen consumption, it requires more expensive and sophisticated equipment than that required by field or field/lab tests. Equipment Quinton Treadmill Heart rate monitor Metabolic measurement system Procedure 1. Obtain the subject s height and weight (enter all information into the metabolic system) 2. Place a heart rate monitor on the subject. 3. Position the subject on the treadmill (instruct them to straddle the belt) 4. With the respiratory valve in place position the noseclip. 5. Have the subject warm-up for 2-5 minutes. 6. Follow the Bruce Treadmill Protocol (or other) Table 2 to obtain the proper speed and % grade. 7. Heart rate should be measured every minute during exercise. Page 2

3 8. Ratings of perceived exertion (RPE) should be measured at the end of each stage and at maximal exercise. 9. Upon termination instruct subject to continue walking on the treadmill (i.e. cool-down) for at least 5 minutes Computations 1. Calculate O 2 pulse for each minute during the exercise test. VO 2 (ml/min) HR (bts/min) = O 2 pulse (ml*beat) 2. Plot VO 2 (L/min & ml/kg/min), heart rate (bts/min), RER VCO 2 (L/min) and VE (L/min) as a function of exercise time during the treadmill test. 3. Calculate MET values for the last minute of each stage of the exercise test. MET level = VO 2 (ml/kg/min)/3.5 (ml/kg/min) 4. Plot HR as a function of the MET equivalent for each exercise stage of the exercise test. 5. Plot VE (L/min) as a function of VO 2 (L/min) for each minute of the exercise test and try and determine the Ventilatory Threshold. What is the HR at the Ventilatory Threshold? Discussion Questions: 1. What was your subject s fitness ranking according to your previous laboratory? Would this ranking change if the subject were 45 years old? 2. Did the prediction tests performed in the previous laboratory yield a VO 2max value that was similar to the actual VO 2max (as obtaind from the treadmill test)? 3. If the same subject were to come back in two days and perform a VO 2max test on a cycle ergometer, What do you think their VO 2max would be (higher, lower, no change)? Why? 4. Explain the importance of the cool-down during this exercise assessment. 6. What was the primary pathway used during the Wingate test? 7. What is the fatigue ratio (%) of your subject? What does this mean? Page 3

4 8. Does the Wingate Test have relevance to any sports or activities? If so, give a few examples and explain the relevance. 9. Explain the importance of the cool-down during both exercise assessments. Page 4

5 Table 2. VO 2max Report - Bruce Treadmill Protocol Start Warm-up at Start Exercise at Time Speed Grade VO 2 RER HR RPE (min) (mph) (%) (ml/kg/min) (b/min) Overall 0-1 Stage Stage Stage Stage Stage Stage Total Exercise Time: min Maximal Heart Rate: b/min RERmax: VO 2max : ml/kg/min METSmax: Comments: Page 5

6 Modified Astrand Treadmill Running Protocol (Pollock et al., 1978) Warm-Up 2-3 min of Walking/Jogging OMNI Scale Speed Time Grade VO 2 VO 2 VCO 2 VE RER HR Legs Chest Overall (mph) (min) (%) (L/min) (ml/kg/min) (L/min) (L/min) (b/min) 0-1 Stage Stage Stage Stage Stage Stage Stage Stage Total Exercise Time: min RER max : Maximal Heart Rate: b/min VO 2max : ml/kg/min Comments: Page 6