In sports of a cyclical nature (e.g., running, cycling, kayaking), the goal is to cover a given distance in the shortest time possible. An optimal pacing strategy to distribute effort over the course of the race is considered a key element in the final outcome (25,29). The definition of a pacing strategy is that it is the conscious or subconscious regulation of work output according to a predetermined plan to maximize performance without causing irreparable harm to physiological systems (1). There have been studies on pacing strategies in such sports as cycling (7), speed skating (21), kayaking (3), rowing (12), and running (13,19). According to these studies, in some sports, including speed skating, kayaking, rowing, and 5-km running, there is evidence that a fast start (positive pacing) is the optimal strategy (3,12,13,21), whereas in other long-distance sports, including cycling and marathon running, a slow start (negative pacing) may be beneficial (20), suggesting that a constant speed could be more effective in long-distance competitions.
Swimming is a cyclic sport. The goal is to swim a given distance in the shortest time. The Olympic calendar of individual (pool) events includes 100- and 200-m backstroke, breaststroke, and butterfly; 50, 100, 200, 400, 800 m (women) and 1,500-m (men) freestyle; and 200- and 400-m individual medley. These last 2 events involve a quarter of the distance each of butterfly, backstroke, breaststroke, and freestyle (i.e., any other style that has not been used previously, normally the crawl stroke). A performance analysis of these events is an important step toward defining training programs and predicting a swimmer's lap times. There have been many such studies in the fields of biomechanics (10), kinanthropometrics (31), physiology (23), psychology (6), talent selection (26), and competition performance (11), among others. These works have focused mainly on the analysis of kinematic variables—stroke rate and length, swimming speed, and starts and turns, in both Olympic (2) and non-Olympic (5) swimmers. However, there have been relatively few studies that have considered pacing strategies and performance improvement in competition. Examples in the last few years include proposals of pacing strategies (18) and studies of young swimmers at a national level (22) and international swimmers (15,25). By positive pacing, one understands the strategy in which the first half of the race is swum faster than the second, of course, taking into account that the first lap swum is normally the fastest given the effect of the start on its partial time (18). By negative pacing, one understands the strategy in which the 2 halves of the race tend to be swum in equal times. The results that most stand out from these studies are that the winners of 100-m races (butterfly, backstroke, breaststroke, and freestyle) set a rapid pace in the first section (positive pacing), those of the 200- and 400-m (same styles) set a more even pace, although some 400-m freestyle swimmers finish faster (negative pacing), and finally 800- and 1,500-m freestyle winners set a generally steady pace (18) but finish somewhat faster than in the first half of the event. In the 200-m freestyle, at the adult national level, women use positive pacing, whereas men use negative pacing (22). At the international level, there is an apparent tendency toward positive pacing, but the finalists show very strong correlations of their final time with the second 50-m half of 100-m events, and with the middle two 50- and 100-m sections of 200- and 400-m events, respectively (25). The pattern of lap times is similar for the top 16 swimmers and for the best and worst of the finalists (24).
Although the order of the styles in individual medley is determined by the regulations (butterfly, backstroke, breaststroke, and freestyle), it is to some extent possible to distribute the effort into the different sections by a strategy that is closer to either “positive pacing” or “negative pacing,” but stroke changes and stroke predominance make it particularly difficult to perceive the proper pace, and one really needs objective recommendations in this event. However, to the best of the authors' knowledge, no study has as yet analyzed which pacing strategy is used in 200- and 400-m individual medley races in a large sample of international competitions and which style is the most determinant for the final performance (race time). Thus, the purpose of this study was to ascertain the pacing strategies employed in the 200- and 400-m individual medley and which style was the most determinant for the final performance as a function of sex (men and women) and classification (1st to 3rd, 4th to 8th, 9th to 16th) in international competitions.
Experimental Approach to the Problem
Pacing strategies in swimming events of a given style have been studied previously (15,23,25), but there have been fewer studies of the individual medley (4,18). This may be because of the complexity of these events, which require mastery of 4 swimming techniques and specific combined turns. This study was an inferential analysis based on the examination of trends in pacing strategies in 200- and 400-m individual medley over the past 12 years in international events. The aim was to determine the distribution of the time used in each of the styles so that this could serve as a reference to coaches for training and competition. The dependent variables were the resulting splits expressed as percentages of the total time employed in each style, whereas the independent variables were sex and final classification (3 levels). The motivation for choosing sex as an independent variable and for grouping variables was that previous studies (18) had found sex to influence which pacing strategy was applied, and the choice of classification was based on the hypothesis that the final classification in the event would be influenced by the relative predominance (fraction of the total time) of each style.
We analyzed 26 international competitions: 3 Olympic Games (2000, 2004, 2008), 5 World Championships (2003, 2005, 2007, 2009, 2011), 6 European Championships (2000, 2002, 2004, 2006, 2008, 2010), 3 Commonwealth Games (2002, 2006, 2010), 3 Pan Pacific Games (2002, 2006, 2010), 3 U.S. Olympic Team Trials (2000, 2004, 2008), and 3 Australian Olympic Trials (2000, 2004, 2008). This was thus a retrospective analysis covering a 12-year period (2000–2011). Of the possible 1,664 competitor records (26 international competitions × 16 swimmers × 2 sexes × 2 events [200 and 400 individual medley]), 1,643 records were analyzed in the 2 events together (821 men and 822 women) because there were 21 disqualified swimmers whose results were not included in the official listings.
All the results were retrieved from the Websites of the corresponding championships and are in the public domain. Of the 26 championships analyzed, in 20 of them we used the official timekeeping page of the championship (http://www.omegatiming.com/). Of the remaining six championships, 3 of them (Australian Olympic Trials 2004, 2008; Commonwealth Games 2010) were analyzed using the results of the official website of the event organizer (http://www.swimming.org.au/andhttp://www.cwgdelhi2010.org/), and for the other 3 championships (Commonwealth Games 2002; Pan Pacific Games, 2006; Olympic Games, 2008), the data were taken from a website specializing in swimming rankings (http://www.swimrankings.net/). In these last 3 cases only, the results were checked and compared with the official website. In the other cases, this comparison was unnecessary because they were official sites. The data were retrieved by one of the authors (A.G.H.) and entered manually into an Excel file. They were then subjected to a random check by another of the authors (J.M.S.) to detect possible errors. The use of data that is publicly available on official Websites is usual in the field of analysis of water sports performance (8,25).
Basic descriptive statistics (mean and SD) were used to characterize the sample with respect to both the final time and that of each style plus their percentages. The normality of the data was confirmed by the Kolmogorov-Smirnov test. Two-way analyses of variance (sex [2 levels: men, women] × classification [3 levels: 1st to 3rd, 4th to 8th, 9th to 16th]) were performed for each stroke (butterfly, backstroke, breaststroke, and freestyle). The Bonferroni post hoc test was used to compare means. For the analysis, we used the percentages in each style, because the use of times would result in differences between all the independent variables (sex and classification)—there will always be differences between men and women in times and between medalists and semifinalists. Finally, Pearson's simple correlation coefficient was used to determine correlations between the style (partial time) and the final performance (total time). The values of this statistic were assigned linguistic labels following recommendations in the literature (14): >0.1 small, >0.3 moderate, >0.5 large; >0.7 very large; and >0.9 nearly perfect. A p value of <0.05 was considered to correspond to statistical significance.
Table 1 presents the results corresponding to the 200-m individual medley event. The fastest style (smallest percentage of the total time of the race) was the butterfly for both men and women. The men employed a greater percentage of time in the freestyle (p < 0.001) and less in butterfly (p = 0.002) and breaststroke (p < 0.001) than women did. With regard to the classification, the best swimmers (first to third) employed a greater percentage of time in butterfly and freestyle (p < 0.001) and less in backstroke (p < 0.001) and breaststroke (p = 0.021) than the lowest classified swimmers considered (9th to 16th). There was no interaction between sex and classification except in backstroke (F2,816 = 5.957; p = 0.003). Among medalists, men employed greater time in backstroke than did women whereas men employed shorter time in backstroke than did women among semifinalists.
A similar pattern of results was observed for the 400-m event (Table 2). The men employed a greater percentage of time in the freestyle (p < 0.001) and less in breaststroke (p < 0.001) than women did. With regard to the classification, the best swimmers (first to third) employed a greater percentage of time in butterfly (p < 0.001) and less in backstroke (p = 0.018) and breaststroke (p = 0.024) than did the lowest classified swimmers considered (9th to 16th). There was no interaction between sex and classification.
Table 3 presents the correlations of the times corresponding to each of the styles (partial time) with the final performance (total times) in 200- and 400- individual medley races. All variables in the 4 styles and in all classifications correlated with performance (p < 0.01). For men, in both events for medalists, the backstroke was the most strongly correlated style, whereas from the 4th to the 16th place, it was the breaststroke. For women, in the 200-m event, the backstroke was the most strongly correlated style for medalists, and in the 400-m event, it was the freestyle. Almost all the correlations may be considered as “large” (r > 0.5) or “very large” (r > 0.7), and even “nearly perfect” (r > 0.9) (14). However, in the medalists, the breaststroke correlations were weaker than for the other styles (except in the 400 individual medley women). Also, these breaststroke correlations increased as the placing declined.
The pacing strategy of international swimmers in the 200- and 400-m individual medley was evaluated in this study by quantifying which style is most determinant for their final performance in races and its relationship to sex and final classification. To the best of our knowledge, the present work is the first study of this type.
Overall, the butterfly was the fastest style (lowest percentage) in the 200- and 400-m individual medley regardless of sex and final placing, confirming the finding (25). Also, men employed a shorter time in butterfly than did women indicating a positive pacing strategy adopted by men. On the other hand, for both men and women, in 200-m individual medley events, swimmers complete the first 50-m butterfly 1.00 seconds slower than their best time for a sprint over the same distance, and in the 400 m approximately 2.50–3.00 seconds slower than their fastest times for the 100-m butterfly (18). The men adopted faster swimming speeds over the first half of races (positive pacing), in line with the results observed in 200-m breaststroke races in national and international competitions (27), even though this strategy could lead to increased lactic acid concentrations (28). In 200 m, the women took a significantly greater percentage of their race time in covering this lap (butterfly) than the men (+0.11%; p = 0.002). With respect to the breaststroke, the men swam significantly faster (in terms of percentage of their total race time) than women regardless of their final placing in both 200 m (0.25%; p < 0.001) and 400 m (0.34%; p < 0.001). In contrast, in the last lap (freestyle), women swam significantly faster (in terms of percentage of race time) than men did, again regardless of their final placing, in both 200 m (0.38%; p < 0.001) and 400 m (0.30%; p < 0.001). This seems to indicate that women in general were able to cover the 200- and 400-m races more evenly with a different distribution of effort and were able to finish the race faster in relative terms than men did, perhaps because of a lower accumulation of lactic acid in these events (16) and a butterfly start that is relatively slower than for men.
In the 200-m individual medley, the medalists spend a greater percentage of time in the butterfly section than do the finalists and semifinalists (p < 0.001). This suggests that they economize on energy in this part of the race so as to increase their effort in the backstroke. This is supported by the observation that they invest a smaller percentage of time in this section than do the semifinalists (p < 0.001). Their freestyle sections are, however, relatively slower than those of the semifinalists, perhaps because of the effort they put into the middle sections of the event (backstroke and breaststroke). With respect to the 400 m, the relationship between the different style sections and the classification was almost similar. As one descends in the placing, one finds that the butterfly is swum proportionally faster (p < 0.001). This could indicate less mastery of this style which leads the swimmer to work harder in this section, hence the lower percentages of the total race time (18). With respect to the last half of the event, the relationship seems to be unclear. The only differences are in the backstroke (0.14%; p = 0.018) and breaststroke (0.15%; p = 0.024) between medalists and semifinalists and in the freestyle between finalists and semifinalists (p = 0.039). This may be indicative of different patterns of performance when the classification is lower. Nonetheless, it is important to note that, overall, the better the classification of the swimmer in both the 200- and the 400-m individual medley events, the greater the percentage of their total time is spent in the butterfly, with the inverse being the case for the backstroke and breaststroke with less percentage of time spent in these sections by the medalists in comparison with the semifinalists. In the 200-m medley events, there was an interaction (sex × classification) only in the backstroke (F2,816 = 5.957; p = 0.003), and in the 400-m events, there were no interactions. Thus, these results indicate that only the percentages of the backstroke in 200 m are conjointly dependent on the sex and classification, highlighting the need to develop different training protocols in these styles between men and women individual medley specialists. In particular, they seem to support the idea that there are certain differences in the swimming technique that men and women use in the backstroke (18). The interaction of sex and classification in backstroke indicate its importance in pacing because it to a large part determines a positive or a negative pacing strategy. Finally, although the technical mastery of the 4 styles seems to suggest that 200 and 400 specialist swimmers could carry out their training together, the energy characteristics of the two events are clearly different (17). This study adds support to this idea because the pacing strategy (interaction sex × classification) is different for the 2 distances. Indeed, <40% of swimmers getting medals in a given championship get them in both events.
Focusing on the medalist group, it was observed that in 200-m events the backstroke is the style that most correlates with performance (r values are more often greater than other styles). This is consistent with a previous study corresponding to the Sydney Olympic Games in which the backstroke was found to be the style presenting the strongest correlations (men: r = 0.68, p < 0.05; women r = 0.84, p < 0.05) (4). Another study has shown that the final lap (freestyle) correlates most strongly with final time for both men and women (28). The present finding, that the backstroke was the most determinant style (r value greater than other styles) for the medalists (first to third), showed that successful swimmers start the race at the greatest speed that they can maintain for the 4 sections (20). For the 400-m event, in general, it was observed that the breaststroke in men and freestyle in women were the styles most strongly correlated with the final time, although the analysis by groups showed that the least determinant style for the medalists is the breaststroke. Nonetheless, this is confirmation that the second half of the race is the more determinant for the final outcome (27).
Considering the medalists separately however, in men the second section (backstroke) was the most determinant style (r value greater than for other styles), but in women it was the last section (freestyle) that was most strongly correlated with the final time (18). This was consistent with the findings of three studies that have suggested that an even pacing is preferable in exercise lasting longer than middle distance events, when the energy used is preferentially aerobic (8,9,29). For the 400-m individual medley events, again the breaststroke was the most determinant style in men (finalists), coherent with other recent studies (25). In women, the freestyle continued to be the determinant style in the finalists. Some studies have suggested that improvements in this lap time are associated with performance enhancements that would substantially increase the likelihood of a medal in top-ranked swimmers (24,25,30).
It was concluded that in general the men apply a positive pacing strategy in the 200- and 400-m individual medley events, whereas the women tend to apply a less positive pacing strategy. At the same time, it was found that in both distances men swim the breaststroke section relatively faster than women do (in terms of percentage of race time) but that women swim the freestyle relatively faster than men do. The fastest style for both sexes is the butterfly. For the medalists, in men (200 and 400 m), the backstroke style, which correlated most with their final performance, whereas in women, it is the backstroke (200 m) and freestyle (400 m). The lower the final classification of the group, the more determinant is the breaststroke (men) and the backstroke (women) in the final performance. Although all the groups of the different levels had very different times for the 4 sections, between the groups the section percentages were very similar even though the small differences were statistically significant.
The present results, based on the trends of the last 12 years, suggest that coaches need to apply a differentiated approach in training men and women individual medley swimmers, because for men, the backstroke is the most determinant style for their final performance (medalists) in both the 200 and 400 m, whereas for women, it is that same style (backstroke) in the 200 m but freestyle in the 400 m. In a general form, the percentage distribution of times for the medalists could be as follows (rounded to one decimal place): in the 200-m individual medley men (butterfly, backstroke, breaststroke, freestyle): 21.7–25.3–29.0–24.0% and women: 21.8–25.5–29.1–23.6%; in 400-m individual medley men: 22.8–25.5–28.5–23.2% and women: 22.6–25.3–29.4–22.7%. Coaches could use this distribution of percentages as a reference for training and competition. Simple spreadsheet calculations could be developed to obtain individual split times based on the swimmer's target time and the above percentages, taking the sex differences into account. These calculated split times provide a more precise orientation for specific pace training in the individual medley event. This training would need to include a breakdown of each swimming style combination involved with the corresponding specific turns so that the swimmer can gain a feeling for the real pace in the event despite the stroke change. However, it would of course be necessary to take into account the individual characteristics of each swimmer in their command of the 4 swimming styles. This situation is of particular importance for breaststroke specialists who would be able to attain very rapid times in this lap of the race in contrast to the rest of the individual medley participants who would be more evenly paced (and closer to the split proposed in this article). With respect to pacing strategies, coaches could focus on positive pacing, while not forgetting that the butterfly has to be as “aerobic” as possible, especially in the 400-m individual medley, to avoid small increases of intensity in this first section leading to the early appearance of fatigue processes.
During the completion of this article, J.M.S. and Y.E. were visiting researchers at the University of Wales Institute, Cardiff (United Kingdom), supported by grants awarded by the European Union, European Regional Development Funds (Una manera de hacer Europa) and the Autonomous Government of Extremadura (Junta de Extremadura) (GR10171 and PO10012, respectively). The authors wish to thank R.A. Chatwin, Ph.D., for revision of the English text and A. Arcos, Ph.D., for revision of the statistical analysis. The authors would like to acknowledge the work of the 2 anonymous reviewers who made the quality of the work being improved.
1. Ansley L, Schabort E, St. Clair Gibson A, Lambert MI, Noakes TD. Regulation of pacing strategies during successive 4-km time trials. Med Sci Sports Exerc 36: 1819–1825, 2004.
2. Arellano R, Brown P, Cappaert J, Nelson RC. Analysis of 50-, 100-, and 200-m freestyle swimmers at the 1992 Olympic Games. J Appl Biomech 10: 189–199, 1994.
3. Bishop D, Bonetti D, Dawson B. The influence of pacing strategy on VO2
and supramaximal kayak performance. Med Sci Sports Exerc 34: 1041–1047, 2002.
4. Chatard JC, Girold S, Caudal N, Cossor J, Mason B. Analysis of the 200 m events in the Sydney Olympic Games. In: Biomechanics and Medicine in Swimming. Swimming Science VI. Chatard J. C., ed. Saint-Étienne, France: l'Université de Saint-Étienne, 2003. pp. 261–264.
5. Chollet D, Pelayo P, Delaplace C, Tourny C, Sidney M. Stroking characteristic variations in the 100-m freestyle for male swimmers of differing skill. Percept Mot Skills 85: 167–177, 1997.
6. Coatsworth JD, Conroy DE. The effects of autonomy-supportive coaching, need satisfaction, and self-perceptions on initiative and identity in youth swimmers. Dev Psychol 45: 320–328, 2009.
7. de Koning JJ, Bobbert MF, Foster C. Determination of optimal pacing strategy in track cycling with an energy flow model. J Sci Med Sport 2: 266–277, 1999.
8. Escalante Y, Saavedra JM, Mansilla M, Tella V. Discriminatory power of water polo game-related statistics in 2008 Olympic Games. J Sports Sci 29: 291–298, 2011.
9. Foster C, Schrager M, Snyder AC, Thompson NN. Pacing strategy and athletic performance. Sports Med 17: 77–85, 1994.
10. Ganter N, Witte K, Edelmann-Nusser J, Heller M, Schwab K, Witte H. Spectral parameters of surface electromyography and performance in swim bench exercises during the training of elite and junior swimmers. Eur J Sport Sci 7: 143–155, 2007.
11. Garland SW. An analysis of the pacing strategy adopted by elite competitors in 2000 m rowing. Br J Sports Med 39: 39–42, 2005.
12. Garland Fritzdorf S, Hibbs A, Kleshnev V. Analysis of speed, stroke rate, and stroke distance for world-class breaststroke swimming. J Sports Sci 27: 373–378, 2009.
13. Gosztyla AE, Edwards DG, Quinn TJ, Kenefick RW. The impact of different pacing strategies on five-kilometer running time trial performance. J Strength Cond Res 20: 882–886, 2006.
14. Hopkins WG, Marshall SW, Batterham AM, Hanin J. Progressive statistics for studies in sports medicine and exercise science. Med Sci Sports Exerc 41: 3–13, 2009.
15. Jarrin ML, Escalante Y, Heras M, Saavedra JM. The pacing strategies in 200 m butterfly, 200 m backstroke, 200 m breaststroke and 200 m freestyle in international events (Spanish). NSW 33: 9–26, 2001.
16. Kelly M, Gibney G, Mullins J, Ward T, Donne B, O'Brien M. A study of blood lactate profiles across different swimming strokes. In: Biomechanics and Medicine in Swimming. Swimming Science VI. MacLaren D., Lees A., Reilly T., eds. London, United Kingdom: E. & F.N. Spon; 1992. pp. 227–234.
17. Lavoie JM, Montpetit RR. Applied physiology of swimming. Sports Med 3: 165–189, 1986.
18. Maglischo EW. Swimming Fastest. Champaign, IL: Human Kinetics, 2003.
19. March DS, Vanderburgh PM, Titlebaum PJ, Hoops ML. Age, sex, and finish time as determinants of pacing in the marathon. J Strength Cond Res. 2010. Ahead of print.
20. Mattern CO, Kenefick RW, Kertzer R, Quinn TJ. Impact of starting strategy on cycling performance. Int J Sports Med 22: 350–355, 2001.
21. Muehlbauer TS, Panzer S, Schindler C. Pacing pattern and speed skating performance in competitive long-distance events. J Strength Cond Res 24: 114–119, 2010.
22. Nomura T. Estimation of the lap time of 200 m freestyle from age and the event time. Rev Port Cien Dep 6: 239–241, 2006.
23. Psycharakis SG, Cooke CB, Paradisis GP, O'Hara J, Phillips G. Analysis of selected kinematic and physiological performance determinants during incremental testing in elite swimmers. J Strength Cond Res 22: 951–957, 2008.
24. Pyne D, Trewin C, Hopkins W. Progression and variability of competitive performance of Olympic swimmers. J Sports Sci 22: 613–620, 2004.
25. Robertson E, Pyne D, Hopkins W, Anson J. Analysis of lap times in international swimming competitions. J Sports Sci 27: 387–395, 2009.
26. Saavedra JM, Escalante Y, Rodriguez FA. A multivariate analysis of performance in young swimmers. Pediatr Exerc Sci 22: 135–151, 2010.
27. Thompson KG, Haljand R, MacLaren DP. An analysis of selected kinematic variables in national and elite male and female 100-m and 200-m breaststroke swimmers. J Sports Sci 18: 421–431, 2000.
28. Thompson KG, MacLaren DP, Lees A, Atkinson G. The effect of even, positive and negative pacing on metabolic, kinematic and temporal variables during breaststroke swimming. Eur J Appl Physiol 88: 438–443, 2003.
29. Thompson KG, MacLaren DP, Lees A, Atkinson G. The effects of changing pace on metabolism and stroke characteristics during high-speed breaststroke swimming. J Sports Sci 22: 149–157, 2004.
30. Trewin CB, Hopkins WG, Pyne DB. Relationship between world-ranking and Olympic performance of swimmers. J Sports Sci 22: 339–345, 2004.
31. Zuniga J, Housh TJ, Mielke M, Hendrix CR, Camic CL, Johnson GO, Housh DJ, Schmidt RJ. Gender comparisons of anthropometric characteristics of young sprint swimmers. J Strength Cond Res 25: 103–108, 2011.