The effect of deliberate practice on the technique of national calibre swimmers

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1 Lupo Corrado, Giancarlo Condello, and Antonio Tessitore. (2014). Women s Water Polo World Championships: Technical and Tactical Aspects of Winning and Losing Teams in Close and Unbalanced Games. Journal of strength and conditioning research / National Strength & Conditioning Association., 28(1): Takagi H., Nishijima, T., Enomoto, I., Stewart, A.M. (2005) Determining factors of game performance in the 2001 world water polo championships. J Hum Mov Stud, 49 (5), The effect of deliberate practice on the technique of national calibre swimmers Rod Havriluk 1 1 Swimming Technology Research, Tallahassee, USA Keywords: biomechanics, technique, instruction, measurement, drag coefficient, coaching Deliberate practice strategies are essential to develop expert skill performance (Ericsson, Krampe & Tesch-Römer 1993). Deliberate practice components include: clear instructions, appropriate task difficulty, a sufficient number of skill repetitions, immediate feedback, individualised supervision, a variety of learning strategies, tasks designed to maintain focus in the cognitive and associative learning stages, and replication of superior performance. In contrast, traditional practice in swimming, particularly for older and more competitive teenagers, often emphasises training distance (quantity) over skill instruction (quality). A previous study found that teenage competitive swimmers did not improve their technique (as measured by the active drag coefficient, C d ) when training with traditional practice strategies (Havriluk 2003). In another study (Marinho, Barbosa, Costa, Figueiredo, Reis, Silva & Marques 2010), an eight week training program included only practicing technical drills (consistent with typical traditional practice) and concluded that there was no significant improvement in the C d. In comparison, two deliberate practice studies reported impressive technique improvements. A study with young teenage swimmers showed that a one-week intervention using deliberate practice produced a significant improvement in the C d (Havriluk 2006). In another study, swimmers practiced deliberately during a two hour intervention that included real-time video and hand force feedback and had a 22% increase in average hand force (Jefferies, Jefferies & Donohue 2012). A general lack of emphasis on technique for (particularly more competitive) teenagers may be related to concern for interfering with success, a misperception about the potential impact on performance, and/or an emphasis on increased training distance. The purpose of the present study was to determine the effect of a deliberate practice intervention on the technique of older teenagers (national caliber swimmers) where in comparison to younger teenagers; the habit strength would likely be more resistant to change. Method The study participants were 19 national swim team members (11 males and 8 females) between the ages of 14 and 21. The descriptive statistics for the males were: age (M = 16.2 yrs, SD = 1.4), height (M = 177 cm, SD = 8.0), and mass (M = 65.2 kg, SD = 8.7). The female data were: age (M = 17.4 yrs, SD = 2.1), height (M = 168 cm, SD = 7.6), and mass (M = 64.2 kg, SD = 6.8). Informed consent was obtained. Subjects were pretested sprinting over a 20 m swim to the wall. Hand force and swimming velocity data were collected over the last 10 m (Figure 1). The instrumentation and Aquanex testing protocol were identical to previous studies (e.g. Havriluk 2003, 2006). Each swimmer was tested for all four strokes with about 1 min rest between trials. After the pretest, an instructional intervention included two classroom and three poolside instructional sessions. The intervention was consistent with the concepts of deliberate practice. The 300 BMS2014 PROCEEDINGS

2 specific learning strategies in the present study were designed to address the general characteristics of deliberate practice, as shown in Table 1. Figure 1 Captured screen from testing procedure shows synchronised underwater video image and hand force curves. The vertical gray lines are synchronised with the video image. Table 1 Characteristics of deliberate practice General characteristic of deliberate practice Clear Instructions Appropriate task difficulty Sufficient number of skill repetitions Immediate feedback Individualised supervision Variety of learning strategies Maintain focus in cognitive and associative learning stages Replication of superior performance Specific characteristic of deliberate practice for swimming Images of model to demonstrate optimal technique Precise wording of specific visual and kinesthetic cues that complement the model Swims with focus on the most appropriate cues Drills that isolate focus on select cues Numerous short-distance swims at a slow stroke rate with limited breathing and constant focus Group and individual feedback about compliance with cues immediately after swims Reminders before swims Reinforcement after swims about compliance with cues Feedback after swims about non-compliance with cues Classroom and poolside instruction and analysis Swims and drills that isolate focus on select cues Analysis with quantitative force data and synchronised underwater video Reminders before swims to focus on cues on every stroke Questions about focus on cues following swims Dialog between instructor and swimmers about the use of cues and attention to learning strategies Emphasis on continual control of movements to replicate optimal technique For example, a biomechanical model (Figure 2) was used as one strategy to make the technique instructions as clear as possible. Specific visual and kinesthetic cues were precisely worded to complement the model. As there was some variation in the ability level of the participants, the skills were individually modified to target the appropriate task difficulty. BMS2014 PROCEEDINGS 301

3 Skill repetitions were limited to short distance swims at a slow stroke rate with minimal breathing to maximise focus on the cues. The intervention of this study was too short to include a sufficient number of repetitions for skill mastery; the intent was to include a sufficient number of repetitions so that the participants understood how to focus on the cues on their own while training during the month between the pretest and the posttest. The swimmers were provided with individualised supervision in terms of reminders about cues before swims and feedback about cues immediately after swims. The inclusion of instruction and analysis in both classroom and pool environments ensured a variety of learning strategies. (Feedback about synchronised underwater video and hand force data as shown in Figure 1 is an example.) The continual emphasis on cues was designed to maintain focus in the cognitive and associative phases, as well as reinforce the necessity to replicate superior performance (optimal technique). Figure 2 Biomechanical model for instructing swimmers in the use of specific cues to monitor their own technique Results An ANOVA found that there was a significant overall decrease (improvement) in the C d (F = 5.9, p<.05) from the pretest to the posttest (Figure 3). There was no significant change in swimming velocity (ns), but there was a significant decrease in average hand force (F = 23.9, p<.05). As shown in Figure 4, post hoc tests found a significant improvement in the effect size (ES) of the C d for both butterfly and breaststroke (p<.05). 302 BMS2014 PROCEEDINGS

4 Swimming Velocity (m/sec) and Active Drag Coefficient (Cd) Pretest Posttest Average Hand Force (N) Swimming Velocity Active Drag Coefficient Average Hand Force Figure 3 Changes in swimming velocity, active drag coefficient, and average hand force from pretest to posttest Butterfly Backstroke Breaststroke Freestyle Improvement in Active Drag Coefficient (Effect Size) Figure 4 Technique improvement from pretest to posttest Because of the minimal improvement in freestyle and lack of improvement in backstroke, the sample was stratified into specialists and non-specialists for each stroke, as classified by their coach. Specialists in butterfly, backstroke, and breaststroke were found to improve more in their specialty strokes than non-specialists. Discussion The results demonstrate that even a relatively short duration of deliberate practice can make a meaningful improvement in technique for swimmers of a very high ability level. As shown in Figure 6, the magnitude of the improvement of the older teenagers (age 16) is comparable to the data for younger teenagers (age 13) in another study using deliberate practice (Havriluk 2006). The results suggest that deliberate practice can help overcome the habit strength of swimmers who have performed millions of stroke cycles, as well as provide evidence for continued emphasis on technique instruction with older, high ability level competitors. BMS2014 PROCEEDINGS 303

5 Improvement in Active Drag Coefficient (ES) Butterfly Backstroke Breaststroke Freestyle Stroke Non-Specialists Specialists Figure 5 Technique improvement from pretest to posttest for stroke specialists and non-specialists The results of the short-term deliberate practice treatments compare favorably to data from much longer periods of traditional practice. The deliberately practicing younger teenagers (age 13) improved their C d two years of traditional practice (between swimmers in the 11 & 12 and 13 & 14 age groups from Havriluk 2003) was only slightly la improved their C d practice (between swimmers in the 13 & 14 and 15 & 16 age groups) showed a deterioration in technique (ES = - quality. Quantity of practice (training distance) is important to improve both conditioning and technique. A sufficient number of repetitions is a necessary characteristic of deliberate practice. However, it is critical that each repetition replicate superior performance. As training distance fatigues a swimmer, repetitions are less likely to replicate optimal technique. Gauging an adequate, but not excessive, number of training repetitions is a challenging aspect of coaching. Hopefully, the findings of the present study will encourage coaches to carefully monitor swimmers to ensure that they perform a minimal number of non-optimal repetitions. The greatest technique improvements in the present study were in butterfly and breaststroke. Rushall (2013) explained that even the world s fastest swimmers have excess vertical motion in the bilateral strokes. The drills for butterfly and breaststroke that were used in this study were designed in part, to minimise vertical motion. It seems that activities directed at minimising vertical motion in the bilateral strokes can have a significant and immediate impact on technique for even high ability level swimmers. The greater improvement for stroke specialists than non-specialists suggests that the perceived relevance of the information may be another deliberate practice characteristic. The characteristics listed in Table 1 increase the opportunity for swimmers to practice deliberately. Often, logistics limit inclusion of all the strategies. For example, lack of access to a classroom, constraints on pool space, and staff limitations make it difficult to ensure a complete treatment. However, under many circumstances a number of the strategies can be successfully employed. In particular, individual feedback about both compliance and non-compliance with specific cues is essential. If a swimmer is exposed to a cue enough times, he/she can memorise the phrase and then evaluate his/her technique while swimming. Not only does the swimmer then become proficient at monitoring his/her own stroke, but the constant self-evaluation process maintains focus in the cognitive and associative learning stages so he/she can internalise the feedback process. 304 BMS2014 PROCEEDINGS

6 Deliberate - One Month Age 16 Practice Type Traditional - Two Years Age 13&14 to 15&16 Deliberate - One Week Age 13 Traditional - Two Years Age 11&12 to 13& Improvement in Actice Drag Coefficient (Effect Size) Butterfly Backstroke Breaststroke Freestyle Figure 6 Improvement in the active drag coefficient for younger teenagers (age 13) and national caliber swimmers (age 16) from short-term deliberate practice treatments, as compared to the twoyear difference between comparable age groups. Conclusions The results demonstrate that even a relatively short duration of deliberate practice can make a meaningful improvement in technique for swimmers of a very high ability level. Because of the technique improvement, the swimmers were able to swim as fast on the posttest with less force, and therefore, less effort. It is recommended that coaches emphasise deliberate practice in all training sessions and include the specific strategies for swimming listed in Table 1. The magnitude of the effect of the deliberate practice in the present study will hopefully encourage coaches to emphasise technique instruction for even national caliber swimmers. References Ericsson, K. A., Krampe, R. T. & Tesch-Römer, C. (1993). The role of deliberate practice in the acquisition of expert performance. Psychological review, 100(3), Havriluk, R (2003). Performance level differences in swimming drag coefficient. Paper presented at the VIIth IOC Olympic World Congress on Sport Sciences, Athens. Havriluk, R. (2006). Magnitude of the effect of an instructional intervention on swimming technique and performance. In J. P. Vilas-Boas, F. Alves, A. Marques (Eds.), Biomechanics and Medicine in Swimming X. Portuguese Journal of Sport Sciences, 6(Suppl. 2), Jefferies, S. M., Jefferies, C. M. & Donohue, S. (2012). The effect of real-time feedback on swimming technique. Journal of the International Society of Swimming Coaching, 2(2), Marinho, D. A., Barbosa, T. M., Costa, M. J., Figueiredo, C., Reis, V. M., Silva, A. J. & Marques, M. C. (2010). Can 8- weeks of training affect active drag in young swimmers? Journal of Sports Science and Medicine, 9(1), Rushall, B. (2013). The physics of movements & observations of champions. Paper presented at the annual meeting of the International Swim Coaches Association, Clearwater, FL. BMS2014 PROCEEDINGS 305