Pacing Strategy of 800 m and 1500 m Freestyle Swimming Finals in the World Championships According to the Performance in Males and Females of Different Age Groups

Round 1

Reviewer 1 Report

The manuscript brings interesting information on the pacing strategies in 800-m and 1500-m swimming in male and female swimmers, elite and sub-elite swimmers and young and experienced swimmers. As it could be expected, pacing strategy generally followed a U-shape with significant differences in the frequency and duration of speed changes between the 800-m and 1500-m distances and the study suggests that pacing strategies are influenced by race distance, sex, age, and performance level. The research highlights the complex interplay between physiological and psychological factors that shape a swimmer's decision-making during a race.

This is an anonymized descriptive study, where only the course of swimming performances is analyzed, but the individual psychological and physiological characteristics of individual swimmers are not known. The reliability of pacing strategies for individual groups of swimmers is also unknown; reliability will probably be higher for elite and experienced swimmers than for young and less experienced ones.

Authors may add "Limitations of the study" to their manuscript.

Line 239-240: formal error: In the 800-meter the normalized velocity of the non-medallists was significantly faster than the non-medallists in the 7th split, probably it should be  „velocity of the medallist was faster than in non-medallists..“

Line 327:  … „women typically expend 80% less energy than men do when swimming the crawl at any given speed and with equivalent technical ability“… this statement should be supported by citation, 80 % less seem to be a very big difference.  

Some authors are describing relatively small differences among performances of male and female swimmers (e.g. Zamparo, P. Effects of age and gender on the propelling efficiency of the arm stroke. Eur J Appl Physiol 97, 52–58 (2006). https://doi.org/10.1007/s00421-006-0133-9 or Zamparo, P., Cortesi, M. & Gatta, G. The energy cost of swimming and its determinants. Eur J Appl Physiol 120, 41–66 (2020). https://doi.org/10.1007/s00421-019-04270-y or Knechtle B. et al. Sex Differences in Swimming Disciplines—Can Women Outperform Men in Swimming? Int. J. Environ. Res. Public Health 2020, 17(10), 3651; https://doi.org/10.3390/ijerph17103651)

Author Response

Dear Reviewer,

Thank you for the opportunity to revise our manuscript titled "Pacing strategy of 800-meter and 1500-meter freestyle swimming finals in the World Championships according to the performance in males and females of different age groups" (ID: applsci-2616003).

Thank you for finding the manuscript interesting. Thank you also for your comments that will assist us in improving our manuscript. It is our hope that we have been able to address all your comments.

Here is our point-by-point response.

The manuscript brings interesting information on the pacing strategies in 800-m and 1500-m swimming in male and female swimmers, elite and sub-elite swimmers and young and experienced swimmers. As it could be expected, pacing strategy generally followed a U-shape with significant differences in the frequency and duration of speed changes between the 800-m and 1500-m distances and the study suggests that pacing strategies are influenced by race distance, sex, age, and performance level. The research highlights the complex interplay between physiological and psychological factors that shape a swimmer's decision-making during a race.

Comment

This is an anonymized descriptive study, where only the course of swimming performances is analyzed, but the individual psychological and physiological characteristics of individual swimmers are not known. The reliability of pacing strategies for individual groups of swimmers is also unknown; reliability will probably be higher for elite and experienced swimmers than for young and less experienced ones.

Authors may add "Limitations of the study" to their manuscript.

Response

Lines 540-546: a paragraph has been added at the end of the discussion section to address limitations “The main limitation of the study was that it was purely observational and examined the pacing strategy retrospectively without knowing the race tactics expected before the competition. Information regarding the underpinning mechanisms that explain the behaviours could not be provided. It is therefore only possible to speculate on the physiological, biomechanical, and psychological mechanisms at play. Limitation of the study may also derive by the small number of subjects included in each group since only 8 swimmers take part to the finals of the World Championships...”

Comment

Line 239-240: formal error: In the 800-meter the normalized velocity of the non-medallists was significantly faster than the non-medallists in the 7th split, probably it should be  „velocity of the medallist was faster than in non-medallists..“

Response

Thank you for making us notice our mistake: the correction has been made “In the 800-meter the normalised velocity of the non-medallists was significantly faster than in the medallists in the 7th split (P= 0.008) and significantly slower in the 11th split (P= 0.022).” line 333.

Comment

Line 327:  … „women typically expend 80% less energy than men do when swimming the crawl at any given speed and with equivalent technical ability“… this statement should be supported by citation, 80 % less seem to be a very big difference. 

Some authors are describing relatively small differences among performances of male and female swimmers (e.g. Zamparo, P. Effects of age and gender on the propelling efficiency of the arm stroke. Eur J Appl Physiol 97, 52–58 (2006). https://doi.org/10.1007/s00421-006-0133-9 or Zamparo, P., Cortesi, M. & Gatta, G. The energy cost of swimming and its determinants. Eur J Appl Physiol 120, 41–66 (2020). https://doi.org/10.1007/s00421-019-04270-y or Knechtle B. et al. Sex Differences in Swimming Disciplines—Can Women Outperform Men in Swimming? Int. J. Environ. Res. Public Health 2020, 17(10), 3651; https://doi.org/10.3390/ijerph17103651).

Response

We appreciate you making us aware of our mistake. The original statement by the author [di Prampero, P.E.; Osgnach, C. Energy Cost of Human Locomotion on Land and in Water. In Muscle and Exercise Physiology; Elsevier, 2019; pp. 183–213 ISBN 978-0-12-814593-7. p. 206, 9.7.1.2 Of Men and Women] was: “When taking into account the different body size (particularly the body surface area which affects substantially the energy cost of swimming), the average energy cost of swimming the crawl, at any given speed and for similar technical skill, in women is about 80% than observed in men.”

Lines 520-523, we amended our text as follows “Additionally, women typically exhibit an energy cost 80% than the one reported for men, when swimming the crawl at any given speed and with equivalent technical ability.”

We also added to that paragraph the following references:

50. Zamparo, P.; Cortesi, M.; Gatta, G. The Energy Cost of Swimming and Its Determinants. Eur. J. Appl. Physiol. 2020, 120, 41–66, doi:10.1007/s00421-019-04270-y.
51. Zamparo, P. Effects of Age and Gender on the Propelling Efficiency of the Arm Stroke. Eur. J. Appl. Physiol. 2006, 97, 52–58, doi:10.1007/s00421-006-0133-9.
52. Knechtle, B.; Dalamitros, A.A.; Barbosa, T.M.; Sousa, C.V.; Rosemann, T.; Nikolaidis, P.T. Sex Differences in Swimming Disciplines—Can Women Outperform Men in Swimming? Int. J. Environ. Res. Public. Health 2020, 17, 3651, doi:10.3390/ijerph17103651.

Author Response File: Author Response.docx

Reviewer 2 Report

Dear Editor,
Thank you for the opportunity to review this manuscript titled "Pacing strategy of 800-meter and 1500-meter freestyle swimming finals in the World Championships according to the performance in males and females of different age groups" (ID: applsci-2616003). This manuscript examines pacing strategies in 800m and 1500m freestyle swimming finals at recent World Championships. The study analyzes race outcomes and pacing parameters across different groups of swimmers to understand how race distance, sex, age, and performance level influence pacing decisions.

Overall, I found this to be an interesting and timely analysis that highlights the complex factors shaping pacing strategy in competitive swimming. The topic is relevant and the manuscript is within the scope of Applied Sciences. The study design and methods are appropriate. The results are clearly presented and discussed in the context of previous literature. However, I do have some comments to help improve the quality of the manuscript:

General Comments:

• The introduction provides good background but could be expanded with more recent studies on swimming pacing and factors that influence pacing decisions. The authors cite older articles from 2008-2011 but pacing research has advanced considerably in the past decade.
• In the methods, more details are needed on the mathematical analyses conducted on the splits data. The authors state they tested for randomness and time series analysis but the specifics are unclear.
• The results rely heavily on figures - text descriptions of key findings are needed, especially differences between groups. Statistical values should also be reported in the text for significant results.
• The discussion could be expanded and re-organized for better flow. Start with a brief recap of key findings, then go into interpretations, comparisons to previous literature, limitations, and conclusions/implications.
• The quality of English grammar and style is fair. Moderate editing for clarity and conciseness would improve readability.
  
  

Specific Comments:

• Page 2, Introduction, Paragraph 2: Provide 1-2 more recent citations on pacing in swimming from the past 5 years.
• Page 3, Methods, Paragraph 3: Provide more details on the mathematical analyses conducted - what statistical tests were used to assess randomness and time series patterns?
• Page 4, Results, Paragraph 1: Report statistical values (p values) for the significant differences found.
• Page 5, Discussion, Paragraph 2: Briefly summarize key findings before launching into interpretations.
• Page 6, Discussion, Paragraph 3: Expand limitations of the study - any issues with methodology, data sources, analyses? How could future studies improve?
  
  

I hope these comments are helpful for the authors as they revise this manuscript for publication. Please feel free to contact me if you need any clarification on my feedback. I look forward to seeing the revised version.

Sincerely

• The quality of English grammar and style is fair. Moderate editing for clarity and conciseness would improve readability.

Author Response

Dear Reviewer,

Thank you for the opportunity to revise our manuscript titled "Pacing strategy of 800-meter and 1500-meter freestyle swimming finals in the World Championships according to the performance in males and females of different age groups" (ID: applsci-2616003).

We are glad that you find the topic relevant and the manuscript appropriate. We also appreciate your comments aimed at helping us improve the quality of our manuscript. We hope we have been able to fulfil all your comments.

Here is our point-by-point response.

General Comments:

The introduction provides good background but could be expanded with more recent studies on swimming pacing and factors that influence pacing decisions. The authors cite older articles from 2008-2011 but pacing research has advanced considerably in the past decade. In the methods, more details are needed on the mathematical analyses conducted on the splits data. The authors state they tested for randomness and time series analysis but the specifics are unclear. The results rely heavily on figures - text descriptions of key findings are needed, especially differences between groups. Statistical values should also be reported in the text for significant results. The discussion could be expanded and re-organized for better flow. Start with a brief recap of key findings, then go into interpretations, comparisons to previous literature, limitations, and conclusions/implications.

The quality of English grammar and style is fair. Moderate editing for clarity and conciseness would improve readability.

Response

Some more recent studies have been included in the introduction and more specifics have been added on the randomness and time series analysis, and the statistical values have been reported in the text for every significant results. As suggested, the discussion has been expanded with a recap of the key findings, interpretation and comparisons to previous literature.

Specific Comments:

Comment

Page 2, Introduction, Paragraph 2: Provide 1-2 more recent citations on pacing in swimming from the past 5 years.

Response

Lines 48-50; 92-102: We expanded some points of the introduction and added the following more recent references.

Casado, A.; Hanley, B.; Jiménez-Reyes, P.; Renfree, A. Pacing Profiles and Tactical Behaviors of Elite Runners. J. Sport Health Sci. 2021, 10, 537–549, doi:10.1016/j.jshs.2020.06.011.

Da Silva, J.K.F. Analysis of the Performance of Finalist Swimming Athletes in Olympic Games: Reaction Time, Par-tial Time, Speed, and Final Time. J. Phys. Educ. Sport 2020, doi:10.7752/jpes.2020.02080.

Gonjo, T.; Olstad, B.H. Race Analysis in Competitive Swimming: A Narrative Review. Int. J. Environ. Res. Public. Health 2020, 18, 69, doi:10.3390/ijerph18010069.

Comment

Page 3, Methods, Paragraph 3: Provide more details on the mathematical analyses conducted - what statistical tests were used to assess randomness and time series patterns?

Response

Lines 146-149: hoping that adding the type of the test and reference could be sufficiently clarifying we modified the paragraph as follows “The null hypothesis that a sequence is a random sample was tested using a typical statis-tical test of randomness based on the number and the maximal length of monotonous phases by keeping track of turning points, phase lengths, difference-signs, rank correlation, records, and rank serial correlation [Aivazian, S. Etude Statistique Des Dependances; Editions MIR: Moscou, 1970].” If deemed useful we could add some real data examples of the mathematical procedure that we applied.

Comment

Page 4, Results, Paragraph 1: Report statistical values (p values) for the significant differences found.

Response

Lines 220, 235-236, 248-249, 263, 279-280, 282, 284-285, 287, 305-307, 309, 311, 330, 334, 349, 351, 353, 356: the P values of the difference are reported in the Tables and reported in the text of all Tables and Figures.

Comment

Page 5, Discussion, Paragraph 2: Briefly summarize key findings before launching into interpretations.

Response

Lines 382-396: A second paragraph summarizing the key findings has been added at the discussion section “The key findings of the study highlighted that the swimmers taken into consideration in the study did not match or break the corresponding world record in either the 800- or 1500-meter races of any of the world championships. In both the 800- or 1500-meter com-petitions swimmers followed the parabolic U-shaped pace but presented significant differences between the two distances in terms of the frequency and duration of speed changes. The number of sequences maintaining an acceleration of the same sign occurred significantly more frequently and the maximal length of sequences resulted significantly longer in the 800 than in the 1500-meter for all groups of swimmers. All the 1500-meter competitions were characterised by “true” time series while the 800-meter competitions presented at least one swimmer that did not upheld a time series for the whole competition. The difference between sexes showed that females significantly lowered their normalised velocity in the central part of the competition in both distances with respect to males. In the 800-meter competition females presented a significantly faster start and males a faster end spurt. Swimmers who reached better performances tended to maintain more constant speeds with smoother pacing patterns.”

Comment

Page 6, Discussion, Paragraph 3: Expand limitations of the study - any issues with methodology, data sources, analyses? How could future studies improve?

Response

Lines 540-550: a paragraph has been added at the end of the discussion section to address limitations and future studies. “The main limitation of the study was that it was purely observational and examined the pacing strategy retrospectively without knowing the race tactics expected before the competition. Information regarding the underpinning mechanisms that explain the behaviours could not be provided. It is therefore only possible to speculate on the physiological, biomechanical, and psychological mechanisms at play. Limitation of the study may also derive by the small number of subjects included in each group since only 8 swimmers take part to the finals of the World Championships. Future study could be implemented by analysing the heath and semi-finals of the events to comprise more subjects in each group. Different strategy could emerge among the different stage of the championships due to strategical issues that need to be considered when planning a meeting.”

Author Response File: Author Response.docx

Reviewer 3 Report

The manuscript is interesting for readers. However, some modifications need to be done before can be considered for publication.

1. Please put the correct article type at the top left of the front page.

2. Lines 44-45: This statement needs a reference.

3. Lines 61-63: This statement needs a reference.

4. Lines 72-76: This paragraph is for what? It is not necessary to exclude it from the previous paragraph. Better to combine them and elaborate more on the issue.

5.  Introduction section: This part should include a research gap. At the current stage, the gap was not clearly defined. The motivation for doing this research should be highlighted too. Why this study is really needed in the literature? How about the previous literature, what are missing?

6. The method is well written.

7. Line 165: The table should be after sentences. please correct it.

8. Line 175: Same as this table 2, move it after sentences.

9. Line 184: Same comment

10. Figure: All figures should be after calling the figure name.

11. Authors should include the limitation of work. Describe the future studies that could be conducted too.

12. More discussion is needed. The authors should compare their results with other data from other literature. And discuss the similarity and differences, and discuss why that happened.

13. References are good

I suggest the authors send the manuscript to proofread services for improvement

Author Response

Dear Reviewer,

Thank you for the opportunity to revise our manuscript titled "Pacing strategy of 800-meter and 1500-meter freestyle swimming finals in the World Championships according to the performance in males and females of different age groups" (ID: applsci-2616003).

We are glad that you consider the manuscript is interesting. We value your suggestions for how we can make our manuscript better as well. We sincerely hope that we have all of your comments addressed.

Here is our point-by-point response.

Comment

1. Please put the correct article type at the top left of the front page.

Response

Line 1: We classed the manuscript as “Original Article”.

Comment

2. Lines 44-45: This statement needs a reference.

Response

Line 46: we added the reference to the statement “In open water swimming it has been reported that swimmers competing in the shortest event had a minimal gap between them and the leaders had begun the race in the head group.”

Veiga, S.; Rodriguez, L.; González-Frutos, P.; Navandar, A. Race Strategies of Open Water Swimmers in the 5-Km, 10-Km, and 25-Km Races of the 2017 FINA World Swimming Championships. Front. Psychol. 2019, 10, 654, doi:10.3389/fpsyg.2019.00654

Comment

3. Lines 61-63: This statement needs a reference.

Response

Line 67: the reference has been added to the statement “Due to the low mechanical efficiency of swimming the correct administration of the available energy is also highly dependent on technical abilities.”

Barbosa, T.M.; Bragada, J.A.; Reis, V.M.; Marinho, D.A.; Carvalho, C.; Silva, A.J. Energetics and Biomechanics as Determining Factors of Swimming Performance: Updating the State of the Art. J. Sci. Med. Sport 2010, 13, 262–269, doi:10.1016/j.jsams.2009.01.003

Comment

4. Lines 72-76: This paragraph is for what? It is not necessary to exclude it from the previous paragraph. Better to combine them and elaborate more on the issue.

Response

Lines 73-81: the two paragraphs have been merged. “At least 90% of the energy used during the 800 and 1500-meter freestyle competitions is thought to come from aerobic metabolism [18,20]. Indeed, numerous swimmers actually compete in both distances due to their similar energy requirements. Although few studies have compared their race tactics, it appears plausible that they adopted similar pacing strategies, so a parallel analysis of the two events may be instructive [7,8,21]. Studying the pace strategy in events with similar energetic resources but different durations may aid in understanding how much pacing decision-making is influenced by external factors [19,22,23].”

Comment

5. Introduction section: This part should include a research gap. At the current stage, the gap was not clearly defined. The motivation for doing this research should be highlighted too. Why this study is really needed in the literature? How about the previous literature, what are missing?

Response

Lines 92-102: a paragraph has been added in the introduction to underline the literature gap and the need for the present study. “It has been highlighted that most studies on swimming pacing strategy have been conducted on 200 and 400 m events, while there is limited research on long-distance swimming [6]. Among long-distance pool swimming studies, some have analysed males and females 800 and 1500 m freestyle competitions, but none of them discussed the differences in pacing strategy between sexes nor between distances [7,21]. There is therefore a very strong rationale for updating the study of pacing strategy to provide the most actual individualised spectrum of the best pacing strategy., To this purpose the analysis of real world-top-level competitions should need to be differentiated by sex, age, and competition level. The direct comparison of the pacing strategy adopted in the longest world championship swimming events could help understanding the mechanism underpinning swimmers’ tactical choices.”

Comment

6. The method is well written.

Response

Thank you for appreciating it.

Comment

7. Line 165: The table should be after sentences. please correct it.

Response

Lines 216-221: the text has been moved before Table 1.

Comment

8. Line 175: Same as this table 2, move it after sentences.

Response

Lines 232-236: the text has been moved before Table 2.

Comment

9. Line 184: Same comment

Response

Lines 246-251: the text has been moved before Table 3.

Comment

10. Figure: All figures should be after calling the figure name.

Response

All tables and figures have been moved after the text.

Comment

11. Authors should include the limitation of work. Describe the future studies that could be conducted too.

Response

Lines 540-550: a paragraph has been added at the end of the discussion section to address limitations and future studies. “The main limitation of the study was that it was purely observational and examined the pacing strategy retrospectively without knowing the race tactics expected before the competition. Information regarding the underpinning mechanisms that explain the behaviours could not be provided. It is therefore only possible to speculate on the physiological, biomechanical, and psychological mechanisms at play. Limitation of the study may also derive by the small number of subjects included in each group since only 8 swimmers take part to the finals of the World Championships. Future study could be implemented by analysing the heath and semi-finals of the events to comprise more subjects in each group. Different strategy could emerge among the different stage of the championships due to strategical issues that need to be considered when planning a meeting.”

Comment

12. More discussion is needed. The authors should compare their results with other data from other literature. And discuss the similarity and differences, and discuss why that happened.

Response

Lines 479-539:  the discussion section has been rearranged and expanded. “Our results are consistent with previous analysis of the world records trend. The progression of world records exhibits an exponential decaying pattern, according to an epidemiological analysis of sporting events published in 2008. For the following 20 years, half of all world records will not be improved by more than 0.05% [33,34]. More recently the impact of the COVID-19 pandemic on performance has been studied revealing that the level of performances has decreased significantly in long-distance swimming rather than in the short distances [35–37]. However, a study inspecting ways to enhance front crawl performance concluded that even at the very elite level, a fine-tuning of each aspect of performance in the different phases of the race could elevate an elite swimmer to podium-level performance. The swimming phase of the freestyle event, which lasts the longest, is the one with the greatest potential for improvement (60%), followed by the start (26%) and turn (14%) phases. The potential for improvement was estimated to be between 0.013 seconds for the start phase reaction time and 1.0 seconds by maximising mid-pool kicking [38].

In agreement with earlier studies, long-course pool endurance swimmers adopt a pace with the highest velocity at the beginning and on the last laps of the race, with a stable velocity in the middle of the race [7–9,14,20,21,39,39–42]. Indeed, swimmers with parabolic pacing profiles performed significantly better than the swimmers who displayed other pacing profiles [3].[40].The tele-anticipation model, whose goal is to conserve energy so that a final sprint can be performed afterward, is a likely explanation for athletes engaging in a slower rhythm in the second half of the 1500-meter and in the middle of the 800-meter race [43]. Consistent results have been reported for 3000-metre poll swimming with a first half of the race faster than the second half [44]. Changes in stroke frequency and length that reflect the onset of local fatigue may be the cause of a de-creased velocity in the second part of the race [45]. While shorter races could involve more frequent adjustments in speed, success in long-distance pool swimming seems to be associated with a more conservative pace that allows for increases in speed in the final laps [8,46,47]. The increase in speed at the last splits of the races has typically been observed in head-to-head competitions, where winning depends on outperforming rivals by a small margin [3,48]. Winners of such competitions appear to have the energy reserves necessary for an end-spurt to possibly outsprint a rival in the final few metres [8,9]. The ability of the swimmer to generate propulsion in the most efficient way possible has been shown to be a crucial factor in determining swimming performance [18,49–53]. The ability to effectively allocate energy develops in relation to an individual's cognitive and physical characteristics and is dependent on the amount of prior specific experience [54–56]. The ideal pacing technique can thus be acquired by a wealth of training and competition experience [16,18,57,58]. Since an ideal ratio between stroke rate and stroke length is necessary to maintain the pace throughout the race, key variables like stroke rate, stroke count, split times, and rating of perceived exertion are probably crucial training tools to optimise the development of pacing skills [59–63,50,64–66].

The different mental and physical abilities required to implement these strategies could explain the different approaches taken by male and female competitors [17]. Additionally, women typically expend 80% less energy than men do when swimming the crawl at any given speed and with equivalent technical ability. The anthropometric differences between the male and female body types account for this disparity between the sexes [51]. Therefore, males and females may benefit from slightly different pacing behaviours [4]. Junior swimmers showed a faster central part of the race in the 1500-meter than in the 800-meter competitions. Their first part of the race resulted slower than the elites in both distances. It is likely that pacing skill development needs to begin at a young age being a crucial step towards elite performance [1,4,67].

Given that most swimmers compete in multiple events of varying distances and sometimes strokes, it can be difficult to balance the training programme to ensure that each swimmer's needs are met. Swimmers may race alternate events early in the season to gain race experience and become more specific in event selection as the season progresses. This approach may be beneficial in increasing the frequency of practise in each event and developing the ability to switch paces with ease [57]. Trainers can provide feedback on split times during training sessions on a regular basis and, if possible, during races to as-sist athletes in developing their performance template. It is hypothesised that by doing so, athletes can learn to link bodily sensations (such as perceived exertion, heart rate frequency, breath frequency, fatigue, and pain) to their performance [57].”

Comment

13. References are good

Response

Thank you for the appreciation.

Author Response File: Author Response.docx