Performance differences for intermediate rock climbers who successfully and unsuccessfully attempted an indoor sport climbing route

Transcription

1 International Journal of Performance Analysis in Sport 2011, 11, Performance differences for intermediate rock climbers who successfully and unsuccessfully attempted an indoor sport climbing route Nick Draper, Tabitha Dickson, Simon Fryer and Gavin Blackwell School of Science and Physical Education, University of Canterbury, Christchurch, New Zealand. Abstract As a popular recreational and competitive adventure sport the research base for rock climbing has developed in parallel with the growth of the sport. To date researchers have not attempted to explain the performance differences between those who successfully complete an ascent of a route and those who fall en-route. The aim of our study was to identify factors contributing to a successful or unsuccessful ascent of an indoor sport climbing route. Eighteen intermediate level climbers attempted an onsight ascent of a grade 19 Ewbank scale (5.10b YDS, 6a Sport) climb as either a lead climb or top rope. Results indicated that general climbing experience and number of years lead climbing significantly affected success on the route and appeared to provide successful climbers with a greater feeling of self confidence prior to ascent (p < 0.05). This resulted in significantly lower time taken at key points on the route and a lower heart rate throughout for the successful climbers (p < 0.05). Our findings suggest that prior experience plays a significant role in the successful climbing performance for intermediate level climbers in an on-sight context, regardless of whether lead climbing or top roping. Keywords: rock climbing, plasma cortisol concentration, psychophysiology, lead climbing, top roping, experience 1. Introduction Rock climbing is an exciting adventure sport with well developed competitive and recreational strands that are practiced throughout the world (Billat et al., 1995, Espana- Romero et al., 2009, Kascenska et al., 1992, Sheel, 2004). The sport is increasing in popularity for researchers as they have attempted to explain key factors that affect rock climbing performance in a variety of contexts (Espana-Romero et al., 2009, Esposito, 2009, Sheel et al., 2003, Wall et al., 2004, Watts, 2004, Watts et al., 2003). To date researchers have examined anthropometrical, biochemical, physiological, biomechanical, and psychological aspects of climbing in an attempt to explain variation in performance for climbers of differing abilities across a range of climbing grades (Draper et al., 2009, España Romero, 2009, Grant et al., 1996, Llewellyn and Sanchez, 2008). Goddard and Neumann (1993), in a textbook devoted to improving climbing performance, highlighted six key aspects that can affect climbing performance; physical 450

2 fitness, psychology, technique and tactics along with the external and background conditions in which a climb takes place. With regard to the physical or physiological aspects of performance, Draper et al. (2009) after a review of coaching and technique improvement textbooks identified four key factors that were regularly highlighted as key determinants of performance for rock climbing these were; strength, power, powerendurance and flexibility. In respect of the psychological aspects that affect performance, researchers have identified differences in anxiety levels, self efficacy and risk taking between climbers of differing ability levels (Llewellyn and Sanchez, 2008, Llewellyn et al., 2008, Sanchez et al., 2009, Hardy and Hutchinson, 2007). While each of these studies has increased our understanding of the sport, it is clear from the research of Mermier et al. (2000) that one performance component alone cannot explain the variance in performance between climbers of differing abilities. Watts (2004) suggested that further investigation of the performance determinants identified by Goddard and Neumann (1993) is still required and specifically that the interaction of these factors merits further investigation. The ultimate aim of a rock climber on a specific route is to complete the climb cleanly, without weighting the rope. There are a number of styles of ascent that can be made on a route. If a climber makes a clean ascent on the first occasion they attempt a route, without having watched a previous climber on the route, or having gained information about the route, this is known as an on-sight ascent. If the climber has information then a clean ascent is described as a flash, or if a route is not made first time, but is achieved after practice it is termed a redpoint. To be claimed as an on-sight, flash or redpoint the route must be lead climbed, that is, the climber must trail a rope between himself or herself and the belayer placing protection to anchors during the ascent. To practice a route for a redpoint ascent, as part of improving performance, a climber will often climb on a top rope, which means to climb with the rope passing from the belayer through a top anchor to the climber. With this style of belaying the climber will normally fall less far and will not have to spend time and energy clipping anchors along the way so they can focus on the correct sequence of moves to complete the route. Previous research has suggested that there are physiological and psychological differences between lead climbing and top roping and also between an on-sight lead climb and a subsequent lead climb (Draper et al., 2010, Draper et al., 2008, Hodgson et al., 2009). These studies, however, reported findings from climbers who all successfully completed the ascents within the study. To date it appears no data has been published identifying performance differences between climbers who successfully complete a route and those who fall in an on-sight context. The aim of our study was to examine differences between climbers who were successful and those who were unsuccessful on the ascent of an indoor sport climbing route. 2. Method 2.1. Participants Eighteen (12 male, 6 female) rock climbers volunteered to take part in the study (mean ± SD; age 25.6 ± 4.5 years, height 1.76 ± 0.09 m, mass 73.1 ± 12.3 kg, body fat 17.9 ± 4.3 %, VO 2max 52.2 ± 8.8 ml kg -1 ml -1. The participants were classified as intermediate 451

3 ability level climbers as they had self reported (within the last 12 months) best on-sight lead and redpoint grades of 18.4 ± 0.5 and ± 1.1 Ewbank (YDS 5.10a and 5.10c, French 5+ and 6a+) respectively. Self reported climbing grades have been shown to be a valid measure of climbing ability and so were used to classify the ability of the climbers in our study (Draper, 2011). The climbers had a mean lead climbing experience of 3.6 ± 3.1 years and were actively involved in the sport, climbing at least once a week on both artificial surfaces and natural rock. The participants were fully acquainted with the nature of the study and were informed they could leave at any time. All participants completed a medical health history questionnaire and gave informed consent prior to taking part in the study. Institutional ethical approval for the study was obtained prior to commencing the research Procedure Participants were required to attend three testing sessions. For each of the three sessions participants were asked to refrain from exercise 24 hours prior to testing and to avoid consuming food within two hours of their arrival at the laboratory or climbing wall. A minimum of two days separated each session. The first session was completed at an exercise physiology laboratory during which anthropometric data were collected and a VO 2max test completed. The second and third sessions were held at an indoor climbing facility. During the second session capillary blood samples were drawn to assay for baseline plasma cortisol concentrations and a familiarisation climb wearing a portable gas analyser was completed. At the third, participants undertook the study climb. The second and third sessions were conducted at the same time of day for each climber to avoid problems associated with the diurnal variation in physiological functioning between tests. At the first session mass and percentage body fat were assessed using an InBody 230 (Biospace, Korea) body composition analyzer. The VO 2max treadmill test was conducted using the athlete led protocol (Draper and Hodgson, 2008) and completed on a Woodway (Woodway, Waukesha, Wisconsin, USA) treadmill. The same portable pulmonary gas exchange analyzer, a Cosmed K4b 2 (Cosmed, Rome, Italy), was used for the VO 2max and the climbing trials, having been air, gas, turbine and delay calibrated prior to each test. At the second session capillary blood samples were collected immediately upon arrival, and then 30 minutes and 60 minutes later from the first (big) toe of their left foot. Once blood sampling was complete the climbers completed a familiarisation climbing trial while wearing the K4b 2, which had been modified such that both the battery and analyser unit were worn on the climber s back (total weight 0.7kg) to minimise their impact on the climber s performance. Climbers completed a route of their choice on top rope. At the third and final session all testing was based around completion of the study climbing route. The style of ascent was randomised such that participants either led or top-roped the climb. The lead climb involved clipping bolts (7 pre-placed quickdraws) en-route to protect the climber in the event of a fall. Climbers were asked to complete the route without weighting the rope and to climb at their own pace. The designated test route was 12.15m high set on a Sheer Adventure (Sheer Adventure, Christchurch, 452

4 Canterbury, NZ) indoor artificial wall with the use of modular climbing holds (Uprising Ventures Ltd, Canterbury, NZ). The route was set and confirmed by expert climbers (N = 4) at grade 19 Ewbank scale (5.10b YDS, 6a Sport/French) and given the mean onsight grade of the climbers (18. 4 Ewbank) this meant falling (not completing the route) was a realistic possibility for all participants. Climbers were permitted to use bolt on holds for hands and feet as well as being able to use natural features (smearing) for feet. During the climbing trial capillary blood samples were drawn from the first (big) toe upon arrival, post warm-up, immediately pre-climb, post climb and then 15 and 30 min post climb. After the arrival sample was drawn participants were informed of the route, the grade and their style of ascent (lead climb or top rope). The standardised warm-up consisted of (a) 5 min of light jogging, (b) mobilising/stretching exercises and (c) a single ascent of a route of their choice on a top rope (at least 2 difficulty grades below the designated test route). During the climb participants wore the K4b 2 and a Polar FS1 (Polar Electro, Oy, Kempele, Finland) heart rate monitor Psychological assessment In order to assess their subjective psychological state of the participants completed the Profile of Mood States (POMS) (Grove and Prapavessis, 1992, McNair et al., 1971) questionnaire, the Revised Competitive State Anxiety Inventory-2 (CSAI-2R)(Cox et al., 2003) and the National Aeronautics and Space Administration Task Load Index (NASA-TLX) (Hart and Staveland, 1988). Previous research has indicated that mood state can influence physiological performance (Beedie et al., 2000, Brown, 1993, Harriss, 2009). In order to assess each participant s mood state the POMS questionnaire was administered after the first capillary blood sample was drawn for both the second and third sessions. The POMS 65 item inventory, recorded by participants on a Likert scale from 0 4, measures the individual s perception of tiredness and weariness (fatigue), readiness to partake in physical/mental work (vigour), aggression or hostility (anger), worthlessness (depression) and restlessness (tension). The CSAI-2R was completed by each climber immediately pre-climb, after pre-climb blood sampling. The inventory consists of 17 items (recorded on a Likert scale 1-4) and after being completed by a respondent specific items are combined to provide an overall score for each of the three subscales; somatic anxiety, cognitive anxiety and self confidence. Participants completed the NASA-TLX inventory after the first post climb capillary blood sample had been collected. The NASA-TLX is comprised of six subscales each scored on a Likert scale of All participants were required to record their feelings for the six components; mental, physical and temporal demands of the climb, as well as their feelings about their performance, effort and frustration on the route Plasma cortisol concentrations Capillary blood samples were drawn from the first (big) toe to minimise the impact on the climbers performance, given that; (a) the fingers are needed throughout climbing for gripping and (b) the earlobe can be problematic with regard to drawing larger samples required for plasma cortisol concentration analysis(draper et al., 2006). The first (big) toe was prepared using a non-alcoholic medical wipe (TYCO Healthcare, UK) before sampling, and Haemolance Plus (Haemedic, Poland) lances were used to puncture (1.6mm depth) the skin. The blood samples (300µl) required for determining plasma cortisol concentration analysis were collected using lithium heparin CB300LH 453

5 Microvettes (Sarstedt Aktiengesellschaft & Co, Numbrecht, Germany). All capillary blood samples were stored on ice until centrifugation (cr2000, Centurion Scientific, West Sussex, England) at 10,000rpm for 10 minutes at ambient room temperature. The separated samples were placed in Eppendorf microtubes (Sarstedt Aktiengesellschaft & Co, Numbrecht, Germany) and stored at -20 C for later analysis. The plasma samples were analysed for cortisol using an Enzyme-Linked Immunosorbent Assay (ELISA) method (Dept of Clinical Biochemistry, Christchurch Hospital, Christchurch, New Zealand) as described and validated by Lewis and Elder (1985). A single participants plasma cortisol samples were analysed in entirety in one session to minimise withinsubject variability. All standards and samples were analysed in duplicate. Intra assay coefficients of variation were < 10% Statistical Analysis Prior to any descriptive or inferential analysis, breath by breath oxygen consumption and heart rate data were averaged to each clip and across the whole route. As a consequence, all group data for oxygen consumption and heart rate are presented as mean averaged statistics. After this, all variables were analysed using the Kolmogorov- Smirnov one-sample goodness of fit test and found to satisfy the criteria for normal distribution. Subsequently, data were analysed by style of ascent and by successful ascent or fall to examine performance differences between groups. These analyses were conducted with independent sample t-tests with Bonferroni corrections for the use of multiple tests. Data were analysed using the Statisitics 19 version of the Statistic Package for Social Sciences (IBM, Armonk, USA). 3. Results Analysis of the POMS data indicated that there were no significant differences in the subjective mood state of the participants between the baseline (second) session and the climbing trial (third session). Results indicated that there were no significant differences between the lead and top rope climbers in this on-sight climbing context. Seven climbers (4 male, 3 female) fell from the route during their ascents and 11 completed the climb (8 male, 3 female). For the climbers that fell en-route details of how many reached each of the clips on the route are shown in Fig 1. There were a number of significant differences between those who completed the climb and those who fell during ascent. As can be seen from Table 1 there were significant differences between those who succeeded on the route and those who fell based on their previous general climbing and lead climbing experience, pre-climb self confidence and their mean averaged oxygen consumption during climbing. In addition, those who fell from the climb en-route reported, through the NASA-TLX, the climb as being physically harder and requiring greater effort along with reporting feeling less satisfied with their performance than those who successfully completed the route. To further understand the differences between the climbers who completed the route and those who fell Figs. 1 to 4 were produced to examine key variables to each clip on the route as well as creating a plasma cortisol concentration profile for both groups. As can be seen from Fig 1, the mean time taken to complete each stage of the climb up to clip 5 was longer for those who fell than for those who completed the climb. Between clip 2 and clip 3 this difference was statistically significant (p < 0.05). Although there was a significant 454

6 difference in mean averaged oxygen consumption across the route (Table 1) Fig 2, indicates that mean oxygen consumption to each clip was similar throughout the route for both groups, whereas, as is shown in Fig 3, mean averaged heart rate was higher for those who fell throughout their incomplete ascents. Table 1 Mean ( SD) for factors that distinguished those who completed the climb and those that fell before the top of the climb. Completed climb Fell from climb Climbing experience (years) Leading experience (years) Averaged climb VO 2 (ml. kg -1. min -1 ) * * * Somatic anxiety (Pts) CSAI-2R Cognitive anxiety (Pts) Self confidence (Pts) * Mental demand (Pts) Physical demand (Pts) * NASA-TLX Temporal demand (Pts) Performance (Pts) * Effort (Pts) * Frustration (Pts) Between the start of the climb and clip 1 and between clips 3 4 these differences were statistically significant (p < 0.05). Finally, Fig 4 provides an overview of plasma cortisol concentrations for both groups throughout the study. As can be seen from the figure, plasma cortisol concentrations were very similar during the baseline testing. During the climbing trial, however, from arrival at the climbing wall though to the post climb, and again post 30 min samples, the climbers who completed the route had higher mean plasma cortisol concentrations than those climbers who fell. Conversely, at the fifteen minutes post climb sampling point, which provided the peak plasma cortisol concentration for all climbers, the climbers who fell had a higher mean plasma cortisol concentration than the successful climbers. 455

7 4. Discussion Previous research examining performance in rock climbing has tended to focus on the physiological and psychological characteristics of climbers that were successful on the route(s) selected for the study (Draper et al., 2010, Hodgson et al., 2009, Morrison and Schoffl, 2007, Watts, 2004). Therefore the aim of our study was to identify differences between those who successfully ascended the study climbing route and those who fell en-route. To the best of our knowledge this appears to be the first time that researchers have reported findings for climbers who fell during an ascent as well as for those who completed the route. To ensure there was a possibility of climbers falling during ascent, the grade of the climb (grade 19 Ewbank) was selected such that it was just above the volunteers self reported mean on-sight climbing ability (grade 18.4 ± 0.5 Ewbank). This provided a realistic challenge for the climbers, but one with a significant risk of failure during ascent. The decision resulted in 11 participants being able to successfully ascend the route, while seven fell during the climb. The point at which climbers fell during ascent for comparative purposes is shown in Fig 1 3. As can be seen from these figures, the majority of climbers fell whilst climbing between clips four to six on the route. As is indicated in Fig 1, the climbers that fell took more time to reach each clip during the ascent than those who successfully completed the route. In fact, by the time the majority of unsuccessful climbers had reached clip four they had already taken on average 26% longer to reach that point than the successful ascendents. The findings suggest the time differences were not perhaps due to a more considered style of climbing being adopted by the climbers who fell, but rather that the successful participants climbed more efficiently. The participants responses to the NASA-TLX support this notion for those who fell reported the climb as physically harder and requiring greater effort than their successful counterparts. While mean averaged (between each clip) oxygen consumption was marginally higher (Fig 2) and mean averaged VO 2 (across the whole climb) was significantly higher (Table 1) for the successful climbers, mean heart rate to each clip (Fig 3) was higher (significantly to clip 1 and 4; p < 0.05) for the climbers who fell. From the oxygen consumption data it appears the relative contribution of anaerobic metabolism was higher for the climbers who fell during ascent and the heart rate data suggests these climbers ascended the route at a relatively higher intensity. 456

8 Figure 1. Mean time taken to reach each clip for the successful and unsuccessful climbers. The numbers (from 7 1) on the line for climbers who fell indicates how many climbers reached each clip. * indicates statistically significant (p < 0.05). Figure 2. Mean oxygen consumption to each clip for the successful and unsuccessful climbers. The numbers (from 7 1) on the line for climbers who fell indicates how many climbers reached each clip. 457

9 Figure 3. Mean averaged heart rate to each clip for the successful and unsuccessful climbers. The numbers (from 7 1) on the line for climbers who fell indicates how many climbers reached each clip. * indicates statistically significant (p < 0.05). A novel finding from this research relates to the effect of experience on climbing performance. As can be seen in Table 1, the successful climbers were more experienced in terms of years participating in the sport and with regard to lead climbing (p < 0.05). The greater mean experience of these climbers might have been a key to their successful performances. Previous climbing and lead climbing experience would most likely have had a general influence on the physiological, psychological, tactical or technical components of climbing performance described by Goddard and Neumann(1993). Certainly our data suggest there were physiological and psychological differences between the two groups of climbers. Given, however, the on-sight context of the climbing in our study, perhaps the most likely explanation of the influence of experience on performance might be through its effect on the psychological state of each climber prior to climbing and on the choice of technique and tactics employed by the successful climbers when compared with those who fell en-route. In turn the technical and tactic decisions of each climber would have influenced their relative climbing economy or efficiency(draper and Hodgson, 2008). Research in the field of 458

10 experience and expertise would support this interpretation of our findings (Ericsson, 1996, Ericsson, 2002, Ericsson, 2004, Fitts, 1967, Simon, 1973). Skill related aspects of sports performance, as demonstrated through the technique and tactics employed by a performer, take time to be developed and are laid down gradually due to the need to embed behaviours (Ericsson, 1996, Ericsson, 2002, Ericsson, 2004, Simon, 1973). Further to this, practice and experience have been highlighted as key components in the automation of movement skills (Fitts, 1967). In an on-sight climbing context, reaching the autonomous stage of learning would perhaps have had a stress-proofing effect for the more experienced climbers, thereby increasing the likelihood of successful ascent for those performers(fitts, 1967). Key tactical and technical differences that could have impacted upon climbing performance in this context were route selection and the climber s movement repertoire which in isolation or combination would have enhanced climbing economy (Goddard and Neumann, 1993, Horst, 2003, Peter, 2004). The prior experience, temporal and physiological data in our study perhaps suggest the successful climbers had greater efficiency of movement during ascent than the unsuccessful climbers. With greater experience the successful climbers route planning prior to commencing the ascent and/or during ascent may have decreased the time required to complete each stage of the climb thereby decreasing the relative physiological stress. Interestingly, while there were no significant differences in the subjective feelings of anxiety (somatic and cognitive) between successful and unsuccessful climbers, there was a significant difference in reported self confidence. It could be that the greater depth of experience for those climbers was linked to the higher subjective self confidence as measured by the CSAI-2R. This increased relative self confidence may have improved decisions around route planning for the successful climbers. Support for this possibility can be found from comparison with previous research with intermediate climbers (Draper et al., 2010, Draper et al., 2008). The mean ±SD climbing experience (4.8 ± 3 years) and self confidence (30.69 ± 2.89 pts) reported prior to ascent by the successful climbers in our study were higher and self confidence demonstrated less variation than those reported by Draper et al. (2008) (experience 3 years; self confidence 26.6 ± 5.5 and 26.2 ± 5.2 pts) and later study by Draper et al. (2010) (experience 2.75 ± 1.75 years ; self confidence 26 ± 5 and 29 ± 7 pts). Taken together these findings suggest that for intermediate climbers there may be a relationship between experience and self confidence. The greater a climber s experience the higher their pre-climb self confidence as reported by the CSAI-2R. The time course of mean plasma corticsol concentrations for the successful and unsuccessful climbers are reported in Fig 4. The trend during the baseline was as expected, with the mean concentrations falling across the three points of measurement (during which time the climbers had been resting). Interestingly, during the climbing trial the mean plasma cortisol concentrations were higher from arrival to post climb for the successful climbers than for those who fell during ascent. It might be, in agreement with previous research, that higher arousal levels resulted in higher pre-climb plasma cortisol concentrations for the successful climbers (Hodgson et al., 2009). In a climbing context it has also been shown that the physiological stress of climbing results in increased plasma cortisol concentrations (Sherk et al., 2010). It could therefore be suggested that the higher mean plasma cortisol concentrations found for the successful climbers in our study relate to the increased physiological loading associated with 459

11 completing the route and/or continued increased in-climbing arousal. The relatively higher plasma cortisol concentrations for the unsuccessful climbers found 15 min post climb (all climbers underwent a passive recovery post climb) might be attributed to the psychological significance placed on falling from the route by those climbers. Although these points are interesting to discuss with regard to plasma cortisol concentrations, it must be kept in mind that none of the differences between the successful and unsuccessful climbers were statistically significant. As a consequence, further research in this area would be necessary to verify the points made here. Figure 4. Mean plasma cortisol concentrations at various time points for the successful and unsuccessful climbers The aim of this study was to examine performance differences between successful and unsuccessful intermediate level climbers during ascent by top rope or lead climb of a route near to their maximum on-sight abilities. Results indicated that for an on-sight context the style of ascent did not affect performance. The prior general climbing and lead climbing experience did appear to influence successful ascent of the climb. The successful climbers had significantly more experience than the unsuccessful climbers. Our findings support the notion that increased experience influences pre climb self confidence, along with technique and tactics, resulting in a lower physiological stress and a greater likelihood of success during an ascent close to an intermediate climber s personal best performance. Future areas of research that might be pursued, leading on from the findings of this study, would include investigation of these differences in indoor and outdoor climbing contexts as well as examination as to the extent to which experience distinguishes successful and unsuccessful ascents for advanced and elite 460

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