Recently, Martin et al1 described the pacing strategy ... strategy observed by Martin et al could be related to bad ... Tony Meireles Santos, Federal University of.
International Journal of Sports Physiology and Performance, 2013, 8, 351 © 2013 Human Kinetics, Inc.
www.IJSPP-Journal.com letter to the editor
The Influence of Start Position on Even-Pacing Strategy in Mountain Bike Racing To the editor:
Recently, Martin et al1 described the pacing strategy in a real multiple-lap mountain-bike race. The methodological approach used a GPS (Garmin, Edge 305, USA) system to provide continuous speed, distance, elevation, and heart-rate data, which were sampled at 1 Hz during 5 laps for 6 mountain bikers (27.2 ± 5.0 y, 176.8 ± 8.1 cm, 76.3 ± 11.7 kg, 55.1 ± 6.0 mL · kg–1 · min–1). Based on these data, an “even-pace strategy” was observed across the 5 laps, with high variability within each lap. These results were interpreted according to a dynamically regulated effort model, and the authors concluded that even interlap pacing was adopted as an anticipatory mechanism. However, this interesting study did not provide power-output data, and an analysis of this variable distribution is important for understanding how exercise is regulated. Furthermore, these results are contrary to the higher power output2,3 and intensity (heart rate)4 found at the beginning when compared with the rest of the event. Unpublished results from our lab also reinforce this scenario. We found a linear decrease (by lap) in performance (13.4 ± 7.1 W) during a simulated 4-lap mountain-bike race (Computrainer™, criteria validity of r = –.84, P < .01, reliability of ICC = .96, and TEM = 1.4%). Martin et al did not report the positions of the athletes on the start grid or the finish position. In addition to the high intensity of the starting phase of the race, the position of the athlete on the starting grid is also important. Macdermid and Morton5 showed a positive association (R2 = .64, P < .01) between the starting and finishing positions of the athletes in the Mountain Bike World Cup. During the race, the majority of athletes varied their positions no more than 15 and 10 positions for males and females, respectively. The authors attributed these results to an increased number of competitors (133% for males and 186% for females over
10 years), which increased the difficult of overlapping for single tracks and during other critical portions of the race. Based on this interpretation, it was concluded that the pacing strategy in the mountain-bike race depends on the start position. It is therefore possible that the even-pace strategy observed by Martin et al could be related to bad positioning of their subjects on the start grid. Bruno Ferreira Viana, Gama Filho University, Brazil Allan Inoue, Estácio de Sá University, Brazil Tony Meireles Santos, Federal University of Pernambuco, Brazil
References 1. Martin L, Lambeth-Mansell A, Beretta-Azevedo L, Holmes LA, Wright R, St Clair Gibson A. Even between-lap pacing despite high within-lap variation during mountain biking. Int J Sports Physiol Perform. 2012;7(3):261–270. 2. Viana B, Impellizzeri FM, Inoue A, Santos TM. Pacing strategy during a simulated mountain bike racing. Paper presented at: 17th annual Congress of the European College of Sport Science. Book of Abstracts. 2012; Bruges, Belgium: 297. 3. Stapelfeldt B, Schwirtz A, Schumacher YO, Hillebrecht M. Workload demands in mountain bike racing. Int J Sports Med. 2004;25(4):294–300. 4. Impellizzeri F, Sassi A, Rodriguez-Alonso M, Mognoni P, Marcora S. Exercise intensity during off-road cycling competitions. Med Sci Sports Exerc. 2002;34(11):1808–1813. 5. Macdermid PW, Morton RH. A longitudinal analysis of start position and the outcome of World Cup cross-country mountain bike racing. J Sports Sci. 2012;30(2):175–182.
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