Effect of Competitive Distance on Energy Expenditure During Simulated Competition

Abstract

Concepts of how athletes should expend their aerobic and anaerobic energetic reserves are generally based on results of tests where an “all out” strategy is imposed on/required from the athlete. We sought to determine how athletes spontaneously expend their energetic reserves when the only instruction was to finish the event in minimal time, as in competition. Well trained, and task habituated, road cyclists (N = 14) completed randomly ordered laboratory time trials of 500 m, 1000 m, 1500 m and 3000 m on a windload braked cycle ergometer. The pattern of aerobic and anaerobic energy use was calculated from total work accomplished and V·O₂ during the trials. The events were completed in 40.3 ± 0.6 s, 87.4 ± 4.1 s, 133.8 ± 6.6 s and 296.0 ± 7.2 s. The peak V·O₂ during the terminal 200 m of all events was similar (2.72 ± 0.22, 3.01 ± 0.34, 3.23 ± 0.44 and 3.12 ± 0.13 l × min^-1). In all events, the initial power output and anaerobic energy use was high, and decreased to a more or less constant value over the remainder of the event. However, the subjects seemed to reserve some ability to expend energy anaerobically for a terminal acceleration which is contrary to predictions of an “all out” starting strategy. Although the total work accomplished increased with distance (23.14 ± 4.24, 34.14 ± 6.37, 43.54 ± 6.12 and 78.22 ± 8.28 kJ), the energy attributable to anaerobic sources was not significantly different between the rides (17.29 ± 3.82 , 18.68 ± 8.51, 20.60 ± 6.99 and 23.28 ± 9.04 kJ). The results are consistent with the concept that athletes monitor their energetic resources and regulate their energetic output over time in a manner designed to optimize performance.

Key words

Cycling - pacing - anaerobic energy expenditure

References

• 1 Astrand P O, Rodahl K. Textbook of Work Physiology. 3rd ed. New York: McGraw-Hill 1986: 325
• 2 Bangsbo J. Quantification of anaerobic energy production during intense exercise.  Med Sci Sports Exerc. 1998;  30 47-52
• 3 Bar-Or O. The Wingate anaerobic test: An update on methodology, reliability and validity.  Sports Med . 1987;  4 381-394
• 4 Beaver W L, Wasserman K, Whipp B J. A new method for detecting the anaerobic threshold by gas exchange.  J Appl Physiol. 1986;  60 2020-2027
• 5 Bishop D, Donetti D, Dawson B. The influence of pacing strategy on V·O₂ and supramaximal kayak performance.  Med Sci Sports Exerc. 2002;  34 1041-1047
• 6 Broker J P, Kyle C R, Burke E R. Racing cyclist power requirements in the 4000-m individual and team pursuits.  Med Sci Sports Exerc. 1999;  31 1677-1685
• 7 Craig N P, Northon K I, Conyers R A. Influence of test duration and event specifity on maximal accumulated oxygen deficit in track cyclists.  Int J Sports Med. 1995;  16 534-540
• 8 Craig N P, Norton K I. Characteristics of track cycling.  Sports Med. 2001;  31 457-468
• 9 de Koning J J, Bobbert M F, Foster C. Determination of optimal pacing strategy in track cycling with an energy flow model.  J Sci and Med Sport. 1999;  3 266-277
• 10 Dengle D R, Graham R E, Hones M T, Norton K I, Cureton K J. Prediction of oxygen uptake on a bicycle windload simulator.  Int J Sports Med. 1990;  11 279-283
• 11 Foster C, Snyder A C, Thompson N N, Green M A, Foley M, Schrager M. Effect of pacing strategy on cycle time trial performance.  Med Sci Sports Exerc. 1993;  25 383-388
• 12 Foster C, Thompson N N, Snyder A C. Ergometric studies with speed skaters: Evolution of laboratory methods.  J Strength Cond Res. 1993;  7 193-200
• 13 Foster C, Green M A, Snyder A C, Thompson N N. Physiological responses during simulated competition.  Med Sci Sports Exerc . 1993;  12 877-882
• 14 Foster C, Schrager M, Snyder A, Thompson N. Pacing strategy and athletic performance.  Sports Med . 1994;  17 78-85
• 15 Foster C, deKoning J J, Rundell K W, Snyder A C. Physiology of speed skating. In: Garrett WE, Kirkendall DT (eds) Exercise and Sport Science Philadelphia: Lippincott, Williams & Wilkins, 2000: 885-893
• 16 Foster C, deKoning J J, Hettinga F, Lampen J, LaClair K, Dodge C, Bobbert M, Porcari J P. Pattern of energy expenditure during simulated competition.  Med Sci Sports Exerc (In Press)
• 17 Garby L, Astrup A. The relationship between the respiratory quotient and the energy equivalent of oxygen during simultaneous glucose and lipid oxidation and lipogenesis.  Acta Physiol Scand. 1987;  129 443-444
• 18 Gastin P B, Costill D L, Lawson D L, Krzeminski K, McConnel G K. Accumulated oxygen deficit during supramaximal all-out and constant intensity exercise.  Med Sci Sports Exerc. 1995;  27 255-263
• 19 Gastin P B. Energy system interaction and relative contribution during maximal exercise.  Sports Med. 2001;  31 725-741
• 20 Green S, Dawson B T, Goodman C, Carey M F. Anaerobic ATP production and accumulated O₂ deficit in cyclists.  Med Sci Sports Exerc. 1996;  28 315-321
• 21 Hill D W. Energy system contribution in middle-distance running events.  J Sports Sci. 1999;  17 477-483
• 22 Jeukendrup A E, Craig N P, Hawley J A. The bioenergetics of world class cycling.  J Sci Med Sports. 2000;  3 414-433
• 23 Karlsson J, Saltin B. Lactate, ATP and CP in working muscles during exhaustive exercise.  J Appl Physiol. 1970;  29 598-602
• 24 Lucia A, Hoyos J, Perez M, Santalla A, Chicharro J L. Inverse relationship between V·O₂max and economy/efficiency in world-class cyclists.  Med Sci Sports Exerc. 2002;  34 2079-2084
• 25 McLester J R. Muscle contraction and fatigue: the role of adenosine 5’-diphosphate and inorganic phosphate.  Sports Med. 1997;  23 287-305
• 26 Medbo J I, Mohn A C, Tabata I, Bahr R, Vaage O, Sejersted O M. Anaerobic capacity determined by maximal accumulated O₂ deficit.  J Appl Phys. 1988;  64 50-60
• 27 Medbo J I, Tabata I. Relative importance of aerobic and anaerobic energy release during short-lasting exhausting bicycle exercise.  J Appl Phys. 1989;  67 1881-1886
• 28 Savaglio S, Carbone V. Scaling in athletic world records.  Nature. 2000;  404 244
• 29 Seresse O, Lortie G, Bouchard C, Boulay M. Estimation of the contribution of the various energy systems during maximal work of short duration.  Int J Sports Med. 1988;  9 456-460
• 30 Seresse O, Simoneau J A, Bouchard C, Boulay M. Aerobic and anaerobic energy contribution during maximal work in 90 s determined with various ergocycle workloads.  Int J Sports Med. 1991;  12 543-547
• 31 Spencer M R, Gastin P B. Energy system contribution during 200- to 1500-m running in highly trained athletes.  Med Sci Sports Exerc. 2001;  33 157-162
• 32 St C lair, Lambert M, Noakes T D. Neural control of force output during maximal and submaximal exercise.  Sports Med. 2001;  31 637-650
• 33 van Ingen Schonau GJ, deKoning J J, deGroot G. A simulation of speed skating performances based on a power equation.  Med Sci Sports Exerc. 1990;  22 718-728
• 34 van Ingen Schenau GJ, deKoning J J, deGroot G. The distribution of anaerobic energy in 1000 and 4000 meter cycling bouts.  Int J Sports Med. 1992;  13 447-451
• 35 Ward-Smith A J. Aerobic and anaerobic energy conversion during high-intensity exercise.  Med Sci Sports Exerc. 1999;  31 1855-1869
• 36 Wilberg R B, Pratt J. A survey of the race profiles of cyclists in the pursuit and kilo events.  Can J Sport Sci. 1988;  13 208-213
• 37 Withers R T, Sherman W M, Clarket D G. Muscle metabolism during 30, 60 and 90 s of maximal cycling on an air-braked ergometer.  Eur J Appl Physiol. 1991;  63 354-362