Anaerobic capacity via a maximal run test

Abstract

Quantifying anaerobic power in runners while running is problematic compared to the determination of aerobic capacity. Aerobic capacity is the maximal amount of oxygen consumed during maximal exertion and is assessed primarily by open circuit indirect calorimetry yielding data such as VO2 max, ventilation, and heart rate (Crouter et al., 2001; Nioka et al., 1998). Anaerobic capacity is the maximum amount of adenosine triphosphate (ATP) generated through anaerobic energy systems (Green et al., 1993). Measurements of the contributions of these energy systems during activity can determine the metabolic requirements for exercise performance and the design of sport specific training regimens. Training results in increased A TP production,• which results in more efficient aerobic and anaerobic work for longer periods of time with less muscular fatigue (Nevill et al., 1989; Stathis et al., 1994; Thorstensson et al., 1976; Thorstensson et al., 1975). Quantification of anaerobic capacity requires exhaustive exercise performed at an optimal resistance resulting in a suitable duration (Green et al., 1993; Vandewalle et al., 1987). This type of high intensity activity results in an increase in blood lactate concentrations (Nummela, Alberts et al., 1996; Nummela, Mero et al., 1996). Peak blood lactate concentrations occur approximately seven minutes post exercise (Fujitsuka et al., 1982). Because of the relationship between peak blood lactate accumulation and anaerobic capacity, blood lactate concentration has been reported to be a reliable indication of anaerobic power in both laboratory and field settings. (Fujitsuka et al., 1982; Gratas-Delamarche et al., 1994; Green et al., 1993; Lacour et al., 1990; Ohkuwa et al., 1984; Vandewalle et al., 1987). Anaerobic testing can be divided into two categories: laboratory testing and field testing. Field tests include shuttle runs, sprints, and vertical jumps. Laboratory testing consists of cycle ergometer and treadmill tests. Field tests such as the vertical jump and Margaria-Kalamen stair climb test have been criticized due to the limited duration and low intensity (Vandewalle et al., 1987). However, sprints of various distances ranging from 100 - 400m have been shown to be good predictors of anaerobic capacity (Patton et al., 1987; Scott et al., 1991; Shaver, 1975). Distances over 400m are more directly related to aerobic capacity rather than anaerobic capacity (Shaver, 1975). Blood lactate values correlate with mean velocity for may runners (Ohkuwa et al., 1984), and for females (Lacour et al., 1990) in distances under 40Om. Laboratory sprint tests on treadmills measure anaerobic capacity and protocols such as peak power obtained in the Maximal Anaerobic Running Test (MART) have been found to correlate moderately with .the Wingate Anaerobic Test (r = 0.52) (Nummela, Alberts et al., 1996). Treadmill sprint tests determine anaerobic capacity by run time to exhaustion or by incremental increases in speed until subject cannot keep up with specified intensity for designated time period (Falk et al., 1996; Nummela, Alberts et al., 1996). The use of a treadmill for sprint tests allows the researcher easy control over factors such as speed and incline; however, controversy arises due to the inability to run at maximum speed, difficulty finding an optimal stride, and failure to attain maximal energy requirement (Frishberg, 1983; Schnabel et al., 1983). The Wingate Anaerobic Test (WAnT) is a highly regarded measurement of anaerobic capacity and power. Measurements of peak power, absolute power, relative power and anaerobic fatigue have become the standard for measurement of anaerobic capacity. (Falk et al., 1996; Green et al., 1993; Murphy, 1986; Nummela, Alberts. et al., 1996; Sands et al., 2004; Weinstein et al., 1998) The WAnT has been accepted as an anaerobic test because of its intensity and duration characteristics as well as its simple and inexpensive protocol. The WAnT elicits high concentrations of blood lactate (Inbar, 1996) which has been found to be significantly correlated with mean power for females (r = 0.48 - 0.72) (Gratas-Delamarche et al., 1994; Weinstein et al., 1998). A disadvantage of the WAnT and other cycle ergometer tests is how the data are interpreted for trained individuals who are untrained in cycling. Results from a non-weight bearing anaerobic test are not easily transferable to the playing field where the athlete has to account for his/her own body weight (Sands et al., 2004) and should not be used as a predictor of performance in sport due to specificity of skills (Beckenholdt et al., 1983). Consequently, non-weight bearing cycle ergometer test results may not be indicative of sprint performance (Baker and Davies, 2002) or other weight bearing activities. A 200m sprint was found to correlate with the WAnT for peak power and mean power when related to body size (r = -0.54 and -0.82) (Patton et al., 1987). A 200m sprint takes approximately 25- 35 seconds, when completed as a maximum effort sprint (Hautier, 1994; Patton et al., 1987; Shaver, 1975). World record times for the 200m sprint are 19.32 sec. for males and 21.34 sec for females (Morrison, 2006). This distance provides a duration similar to that of the Wingate protocol; therefore, utilization of the 200m sprint might be an alternative to the WAnT. Thus, a 200m-field test may be a better indication of anaerobic capacity for athletes that have to complete swift bouts of anaerobic running in their sport. The Hawaii Anaerobic Run Test (HART) was introduced in a pilot study completed in the University of Hawaii performance lab. This test utilized a 200m sprint to determine anaerobic capacity in sprinters. The pilot study showed the HART to be a valid and reliable test of anaerobic performance (Smith, unpublished Master's Thesis, 2005). The purpose of this study was two-fold: determine the sensitivity of the HART for runners and cyclists when compared to the WAnT and to determine the relationship between velocity and momentum obtained in the HART test with power values obtained in the WAnT. The hypotheses of this study were: (1) there would be no differences between blood lactate accumulation for runners and cyclists regardless of test; and (2) there would be no differences between runners and cyclists in velocity and momentum collected during the HART or power values collected during the WAnT.