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Time Motion Analysis and Energy Demands for the Sport of Volleyball Brianne Connizzo Introduction to Coaching Spring 2008 Time Motion Analysis 2 In order to create a proper training program, it is necessary to know the energy demands of the sport and the physiology of its athletes. Most sports can be divided into two categories, aerobic and anaerobic, but the division is like a continuum in that there are many sports that are both anaerobic and aerobic. Sports that are solely aerobic are those that involve periods of prolonged activity like long-distance running. Anaerobic activities involve short bursts of energy in which the presence of oxygen is not needed to produce the necessary fuel. This includes short sprints. Volleyball is most often considered an anaerobic sport with aerobic capacities. The level of intensity with respect to aerobic and anaerobic activities changes in the sport of volleyball from position to position as well as front row to back row. Humans have three types of muscle fiber – one type of slow twitch fibers and two types of fast twitch fibers. Slow twitch fibers use the aerobic system to produce energy while fast twitch fibers use oxygen and can produce energy through the anaerobic system. The fast twitch fibers are helpful for fast, explosive movies. Viitasalo et al. (1987) studied the types of fiber used by the Finnish volleyball teams and determined that on average, the players used more fast twitch fibers than slow twitch fibers which proves volleyball to be an anaerobic activity involving fast, powerful movements. Some fast twitch fibers however, the fast oxidative glycolytic fibers (FOGs), can be trained to improve performance in endurance sports. This probably accounts for some of the aerobic capacity of playing volleyball. Time Motion Analysis 3 One of the most common tests of aerobic capacity is heart rate. Heart rate can be measured using a telemetry strap throughout exercise and finding an average heart rate. For volleyball, there is high anaerobic activity followed by periods of rest. The average heart rate is not a reliable source for this analysis because the average will not show the spikes cause by quick sprints. However, studying the maximum heart rate produced during competition can help determine the aerobic capacity of the exercise. For the Finnish national team, the average heart rate held during the competition was 130 beats per minute but the maximum heart rate was almost 190 beats per minute (Viitasalo et al., 1987, 197)! There are a lot of rest periods during a match so the average heart rate doesn’t give any significant results, but because the maximum heart rate was so far away from the average, it shows that there are periods of very high level heart rate followed by periods of low heart rate; this is seen in short sprinting activities which proves volleyball has a large anaerobic capacity. The aerobic threshold (AeT) and anaerobic threshold (AnT) are used to describe the level of intensity of exercise. The level at which blood lactate reaches a concentration of 2 mmol/L, which correlates with about 65% of the maximum heart rate, is the Aerobic threshold. The anaerobic threshold is the point at which lactic acid starts to accumulate in the blood stream. These two tests are useful measures for deciding exercise intensity for training in endurance sports like distance running, cycling, and rowing and for short repeated exercises with long recovery periods as well. According to Viitasalo et al. (1987), the anaerobic Time Motion Analysis 4 threshold during several competitions was 166 beats per minute and the Aerobic threshold was about 145 beats per minute. Since the maximum heart rate is above the anaerobic threshold, it can be concluded that volleyball has anaerobic qualities but the average heart rate (130 beats per minute) is low, which proves there are many aerobic aspects as well. Exercise psychologists define VO2 max as the maximum rate of oxygen consumption. It is the most important factor in determining your ability to exercise for long periods of times; it measures your capacity for endurance. VO2 rates will be very high for highly aerobic sports like rowing which require a lot of endurance. Sports like swimming and short-distance running will have low VO2 max rates because anaerobic exercise does not require as much oxygen to be produced in order to fuel the muscles with energy. Team sports, like basketball and volleyball, will have a VO2 max rate that lies somewhere in the middle of the range because they are both aerobic and anaerobic activities. Viitasalo et al. (1987) tested a set of 10 Finnish Club players and 10 players from the Finnish National Team to find the maximum VO2 rate and found the rate to be between 51.2 and 62.0 with the average being about 56.7 ml/kg/min during both competition and during a treadmill test. Puhl et al. (1982) also produced a mean of 50.6 ml/kg/min with a standard deviation of 5.7. The range for volleyball players during competition could be generalized to anywhere between 50 and 60 ml/kg/min. This value is along the same level as other team sports like basketball and soccer, but it is still low enough for volleyball to be considered “a Time Motion Analysis 5 moderately stressful aerobic sport event,” which means that aerobic capacity is very critical in performance because of the repeated actions performed, especially the vertical jump (Viitasalo et al., 1987, 195). Lactic acid is a byproduct in the process of fermentation during exercise. During intensive exercises like sprinting, the demand for energy is very high and lactate is produced faster than it can be removed. This causes an increase in lactic acid which ensures energy production to be maintained. It is a fuel for muscles to continue to exercise. The concentration of lactic acid in the body right after exercise is a very good indicator of the type of exercise that was just performed. When exercising, energy production depends on both the anaerobic and aerobic system, but the lactic system contributes after the first 20 seconds. Lactate concentration significantly increased during short periods of intense exercises, suggesting that a high lactic acid concentration, taken right after exercise, will prove an aerobic activity. After vertical jumping, Chamari et al. (2001) found that 15 minutes after repeated maximum jumps, the [La-1] was over 2 mmol/L. The authors also proved that lactate increased is induced by intense sprints as opposed to these vertical jumps, which is why the approach caused more fatigue than vertical blocking jumps. The run-up causes a high lactate increase. This runup condition can cause up to a 3.8 mmol/L increase. Hertogh et al. (2004) confirmed this by testing run-up and jump conditions for an attack and found a 3.73 mmol/L increase. This proves that a high lactate concentration will be found in aerobic activities like repeated sprints. In general, the lactate concentration for Time Motion Analysis 6 the duration of a competition was shown to be around 3 mmol/L, which proves that volleyball has aerobic qualities, even though the concentration is low. (Viitasalo et al., 1987, 197). The fitness demands of volleyball are very similar to those rated in Appendix I. Although there is no direct evidence to support these conclusions cited, ratings can be made from personal experience as well as from the logistics of playing the sport in a competitive setting. Volleyball has a great demand for both speed and power. Volleyball players need to be quick on their toes and explosive because it is a very fast paced game. The flexibility for players is average; the back row players have to move into awkward positions to get hardto-reach ball and the front row players have to cut awkward angles with their hitting shoulders, but this quality is not essential to competitive play. Although it seems that a large quantity of strength is needed from volleyball, especially during hitting, this is an illusion caused by a fast arm swing and an explosive approach. The strength rating is low because there is a higher demand for power and agility. This is similar with endurance because although long rallies require lots of energy, there are also long recovery periods; the rating for endurance is medium. Volleyball is a highly anaerobic sport, with some aerobic qualities. Martens (2004) rates the sport as Medium for aerobic and Medium-High for anaerobic. Based on evidence stated above and personal experience, this is a very good analysis. Originally I had thought that volleyball was a purely anaerobic Time Motion Analysis 7 activity, but being a back row player, I don’t get to experience most of the aerobic activity. The aerobic activity is caused by repeated actions like blocking and attacking. This shows an inconsistency between the energy demands of each position, but it is not significant enough to change the general energy demand analysis. Time Motion Analysis 8 Works Cited Chamari, K., Ahmaidi, S., Blum, J. Y., Hue, O., Temfemo, A., et al. (2001). Venous blood lactate increase after vertical jumping in volleyball athletes. European Journal of Applied Physiology, 85(1/2) Puhl, J., Case, S., Fleck, S., & Van Handel, P. (1982). Physical and physiological characteristics of elite volleyball players. Research Quarterly for Exercise & Sport, 53(3), 257-262. Viitasalo, J. T., Rusko, H., Pajalo, O., Rahkila, P., Ahila, M., et al. (1987). Endurance requirements in volleyball. Canadian Journal of Sports Sciences, 12(4), 194-201. Hertogh, C., Chamari, K., Damiani, M., Hachana, Y., Blonc, S., et al. (2005). Effects of adding a preceding run-up on performance, blood lactate concentration and heart rate during maximal intermittent vertical jumping. Journal of Sports Sciences, 23(9), 937-942. Laconi, P., Melis, F., Crisafulli, A., Sollai, R., Lai, C., et al. (1998). Field test for mechanical efficiency evaluation in matching volleyball players. International Journal of Sports Medicine, 19(1), 52-55. Martens, R. (2004). Successful Coaching. (S. Parker, C. M. Drews, K. D. Bernard, & P. Fortney, Ed.). Champaign, IL: Human Kinetics. Time Motion Analysis 9 Appendix I Figure 1: Fitness Demands Chart Sport or Activity Energy Fitness Aerobic Volleyball Medium Muscular Fitness Anaerobic Flexibility Strength Endurance Speed Power High Medium Low Medium High High