Using rhythmicity to promote performance in horizontal jumps: An exemplar of the need for individually-tailored interventions

1 The current study compared and contrasted the optimal regulation of stride patterns in the 2 horizontal jumping events for 6 British athletes of international standard. Long jump and 3 triple jump approach data were collected over a 3-year period in international and domestic 4 competitions and considered against the distances achieved. Results suggest that on approach 5 to the take-off board, the majority of athletes’ jumps of greater length (intra-athlete) are 6 associated with a low variability, rhythmical footfall. Given the variable approach strategies 7 used by the athletes in question, and consequently the theoretical implications the data set 8 holds, tentative conclusions are drawn regarding the means by which scientists and coaches 9 should assess and design suitable performance focused interventions for elite performers 10 based on individual responses. 11 12 13 14 15 16 17 18 19 20 21 22 23 Horizontal Jump Performance Using Rhythmicity to Promote Performance in Horizontal Jumps: An Exemplar of the Need 1 for Individually-Tailored Interventions 2 Determining how skilled performers execute goal-directed behaviours and the means 3 that enable performance to be enhanced is an essential role which applied sport psychologists 4 often conduct in partnership with other scientists. In doing so, scientist-practitioners often 5 seek guidance from the prevailing theoretical and/or empirical paradigms before applying this 6 knowledge to the practical problem at hand. However, this may sometimes take thinking in 7 an erroneous or less than optimum direction, especially in the special cases of elite 8 performers. In this regard, recent evidence suggests that there are significant advantages to 9 examining how skilled performers organise movement patterns on an intra-individual basis, 10 despite commonalities in patterns of co-ordination being evident in participants of similar 11 ability. For example, Chow, Davids, Button, and Koh, (2006) stated that if skilled 12 participants are grouped together for the purposes of movement analysis, effects of interest, 13 such as control strategies may become masked. 14 Support for pursuing applied sport psychology on a case-by-case basis is illustrated by 15 an increasing number of studies that demonstrated individual-specific findings with reference 16 to performers’ coordination, their responses to appropriate sources of information for 17 instruction and adaptation to physical stress. For example, Beavan, Gill, and Cook (2008a) 18 demonstrated that professional rugby union players with broadly similar training backgrounds 19 responded to group-prescribed resistance training through individual hormonal responses. It 20 was determined that certain players responded positively to some training stresses, but not to 21 other forms of resistance training. In a 3-week cross-over design, the same players alternated 22 between sessions that produced high and low levels of testosterone. It was found that 23 favoured exercise selection elicited players’ maximum testosterone response and resulted in a 24 statistically significant strength gain. However, when the less favoured protocol was used, 25 Horizontal Jump Performance there was either no change, or a significant decline in tested strength (Beavan, Gill, & Cook, 1 2008b). Such individualised hormonal responses to training adaptations in professional sport 2 lend credence to the claim that advanced performers should be investigated on an individual 3 basis. 4 Further support for this contention is provided by examples of empirical research that 5 advocated the application of generic instructional principles to elite groups with—in some 6 cases—less than optimum results. Research carried out with shooters (e.g., rifle, pistol, and 7 archery) by Helin, Sihvonen, and Hanninen, (1987) and Landers, Christina, Hatfield, Daniels 8 and Doyle (1980) suggested that shooters performed to an optimised level when they shot in9 between heartbeats when the cardiac cycle is in diastole, or in what is termed the inter-beat 10 interval (IBI). However, analysis of case study data of six elite-level shooters conducted by 11 Bellamy, Collins, Holmes and Loze (1999) indicated that there is insufficient evidence to 12 advocate a universal strategy of shooting during diastole in elite shooters, since four of the 13 six shooters examined actually shot on the beat. Rather, they suggested the essential need for 14 checks that could detect individual patterns associated with better performance. Whilst this 15 example is somewhat dated, it is uncertain whether the application of generic instructions to 16 elite or advanced performers, albeit derived from peer-reviewed empirical work would 17 automatically result in an improvement to personal performance. 18 A more recent example of the contrasting instructional content of pre-performance 19 routines (PPRs) among elite golfers (i.e., mean handicap of +1.5) was uncovered by 20 Cotterrill, Sanders, and Collins (2010). Whilst the content and firing modality of PPRs has 21 been well researched in relation to self-paced skills (Singer, 2002), research conducted by 22 Cotterrill et al. (2010) showed that the development of a PPR for an elite golfer is 23 idiosyncratic; contingent upon their coping resources; factors that constitute their 24 personalities; and a tendency to appraise the context of each golf shot prior to task execution. 25 Horizontal Jump Performance Accordingly, we suggest that working uncritically from theory to intervention is not an 1 appropriate strategy for groups of advanced learners. 2 In light of these two examples (shooting & golf), it is important to reflect upon the 3 work of Newell, Liu, and Mayer-Kress (2005). Specifically, they proposed that different 4 types of information are differentially effective for athletes, and that the efficacy of 5 alternative sources of information is dependent on the task and the skill level of the learner. 6 Consequently, it is unlikely that an athlete’s potential will be maximised if a ‘one instruction 7 fits all’ approach is used. Therefore, the onus is on applied scientists to determine the most 8 effective sources of information to communicate with and inform athletes’ motor systems. 9 For example, in a study that provided concurrent auditory feedback to gymnasts on the 10 pommel horse, body segment alignment improved by 2.3% between the experimental and 11 control groups. Researchers concluded that auditory feedback provided in real-time could be 12 used to correct complex movements (Baudry, Leroy, Thouvarecq, & Chollet, 2006) as 13 opposed to the more commonly applied video techniques. Interestingly, anecdotal evidence 14 suggested that experienced horizontal jumps coaches could listen to the footfall of their 15 athletes, whilst looking in the opposite direction, and were able to confidently assert whether 16 their athlete had jumped well, or not (Moore, 2006). 17 Whilst it seems that some horizontal jumps coaches have become aware of, and 18 utilise, the rhythm engendered by the auditory output of an athlete’s footfall signature on 19 approach to the take-off board, there is interesting empirical research that has demonstrated 20 the beneficial effect of utilising an auditory output to augment visual information. In a 21 complex series of five experiments Vroomen and de Gelder (2000) demonstrated that 22 perceptual organisation in the auditory modality impacted upon perceptual accuracy in the 23 visual modality. Specifically, a high tone embedded in a series of low tones improved 24 detection of a visual target, when the visual target was presented at the same time – provided 25 Horizontal Jump Performance that the tone was abrupt and distinct from background noise or contaminating melodies. 1 These studies demonstrated that auditory stimuli can be used to enhance the detection of 2 visual information. Therefore, it is possible that a holistic rhythm of an athlete’s footfall prior 3 to contact with the take-off board may serve as an aid to improve foot-to-board accuracy – 4 provided an athlete’s footfall patterns are deemed to be relatively stable. 5 Whilst some athletes might not find this modality of movement correction useful, data 6 presented in this paper provide an opportunity for scientists, applied practitioners, and 7 coaches to consider the implications of working with elite performers through an exemplar of 8 this ‘individualised’ approach. Specifically, the applicability of prevailing theoretical 9 paradigms pertaining to the approach and preparation phases of horizontal jumps is critiqued 10 through consideration of data obtained from a cohort of elite performers. 11 Horizontal Jumps: Event demands 12 For athletes participating in horizontal jumps (HJ) the apparent difficulty associated 13 with executing the task lies in direct contrast to the simplicity of the objective. In particular, 14 the challenge rests in the trade-off between maintaining peak horizontal velocity (athletes 15 typically achieve peak horizontal velocities at take-off of 9.4 m/s for men, and 8.6 m/s for 16 women; see Linthorne, 2007) and being accurate on to the take-off board. To maximise the 17 measured distance, the space between the jump take-off and the edge of the take-off board 18 must be minimised. In addition, the athlete is required to create good ‘lift’ at take-off, 19 generating vertical impulse by accelerating body parts upwards during the final contact with 20 the board without employing large braking forces. A key factor in generating vertical lift is 21 the transference of horizontal velocity accrued on the run-up. Therefore, accuracy onto the 22 take-off board, at speed, is critical to eventual distance achieved (Hay, Miller, & Canterna, 23 1986). 24 Horizontal Jump Performance At an elite level the difficulty of “hitting the board” in HJ is exemplified by 1 1 participant in this investigation, an elite horizontal jumper, who had 10 years of