IMPORTANT TERMSIMPORTANT CONCEPTSINTRODUCTIONANAEROBIC POWEREXPERIMENTAL PROBLEMPROCEDURESAMPLE CALCULATIONSIMPORTANT TERMS1. Mean anaerobic power2. Peak anaerobic power3. SpecificityIMPORTANT CONCEPTS1. Resting physiology and anticipation of impending physical exertion. 2. Determining the capacities of lower-limb musculature for generating power using the Wingate Test.3. Relationship of length and intensity of exercise and the contribution of the major energy systems.4. Units of measurement for anaerobic power.5. Concept of specificity, in regards to testing and performance.INTRODUCTIONDuring any form of physical activity ATP is simultaneously produced from the three energy systems. That is, all three energy systems contribute in some manner to mechanical work. The three major energy systems are:1. ATP-PCr system2. Glycolytic energy system3. Aerobic energy systemDuring high intensity, short duration activities, maximal muscle contractions are performed, which recruit high conduction velocity motor units that typically innervate fast-contracting, glycolytic muscle fibers. Due to their high concentrations of glycolytic enzymes and relatively few mitochondria, these fibers tend to produce lactic acid. Lactate is produced regardless of the amount of oxygen available. The proportion of contribution of each energy system varies with both intensity and duration of exercise. We know that all out efforts lasting less than 10 seconds use primarily the ATP-PCr system to provide ATP, while all out efforts lasting from 10-60 seconds utilize anaerobic glycolysis to provide ATP (increasing contribution from glycolysis as exercise time increases from 10 to 60 seconds). This principle should be remembered when employing tests to evaluate anaerobic power for a particular sport or event.When evaluating the maximal capacity of the various energy systems, there are two considerations that must not be overlooked:1. The test should be performed at a maximum effort. For example, an incremental max VO2 test measures the maximal capacity of the aerobic energy system as the participant is pushed to a maximal level of oxygen consumption. During the final stages of the incremental test, the participant is sustaining a level of exercise that represents the maximal capacity of the aerobic of the aerobic energy system.2. The duration of the test should be sufficient to allow maximal contribution from the desired energy system. An incremental exercise test to exhaustion provides little insight to the maximal capacity of either the ATP-PCr or glycolytic energy systems.To properly evaluate the capacity of the anaerobic energy system, a maximal effort should be elicited over aperiod of 30-60 seconds. Both running and cycling anaerobic tests have been proposed, but the Wingate Test, a cycleergometer protocol, is most commonly used. The advantage of the Wingate test is that since it is conducted on a cycle ergometer, power can be measured in precise units. Further, the Wingate test allows for evaluation of both the ATP-PCr and glycolytic energy systems by evaluating power in 5 s intervals during the test.LABORATORY #1: Anaerobic Power and theAnticipatory Response to Exertion1A second aspect of testing in the lab will involve basic physiologic response to exertion, and the anticipatory response that typically precedes it. In many environments, measurement of the true resting state is required, however it is important to remember that these measures may be more difficult to come by than one might assume. Even when there are no demands placed on a participant beyond their own resting metabolism, it is not uncommon for heart rate and blood pressure to be elevated prior to a test. Hormonal responses associated with nervousness can cause what is typically referred to as the flight or fight response. In this, circulating levels of epinephrine and norepinephrine increase. These can increase heart rate and contractility, and constriction of cutaneous vasculature, which can be measured through changes in skin temperature, heart rate, and blood pressure. These responses help prepare the body for physical effort. In order to demonstrate the variations that may occur in cardiovascular response that may occur, regardless of external physical work, we will measure heart rate (HR) at measured intervals prior to each participant’s Wingate test. These will be compared between participants and will highlight the importance of providing true “resting conditions” when taking baseline physiologic measures.ANAEROBIC POWER Recall that power is defined as: Power = (F*D)/TWhere F is the force generated, D is the distance over which the force is applied, and T is the time required to perform the work. In the Wingate test, force is equal to the resistance (kg) applied against the flywheel. Distance is calculated based on the number of revolutions multiplied by the distance a point on the flywheel travels with one pedal revolution. The flywheel on the Monark cycle used in our lab travels six meters per revolution, so distance perrevolution equals six meters. For example, if an individual completed 30 pedal revolutions against a resistance of 2 kg over 30 seconds, the resulting power would be:Power = [2 kg * (6 meters/revolution * 30 revolutions)] / 30 seconds = 12 kg*m/secThe standard unit for power is the watt. One watt is equal to 6 kg*m/min, so the power generated during this exercise test was 120 W:(12 kg*m/sec)*(60 sec/min) (6 kg*m/min)Notice that we have the result (12 kg*m/sec) in seconds, and to convert into Watts, we need our time in minutes. This is why we multiply our result by 60 sec/min, and then use the converting term of 6 kg*m/min.The Wingate test has traditionally been used to evaluate anaerobic leg power. The protocol requires a 30-second all out cycling protocol rate at a fixed resistance. It has been suggested that the resistance should be set relative to an individual’s body weight rather than at an absolute resistance. As body mass is related to muscle size/mass and force generation, a relative resistance allows for comparison of anaerobic power between participants.The Wingate test is designed to determine the power of both peak anaerobic power and mean power output over 30 seconds. The peak anaerobic power is determined based on the peak number of revolutions performed during any single 5-second interval of the test, and represents the power of the ATP-PCR system. The mean anaerobic power