The Effect of Indoor Rock Climbing On Strength, Endurance, and Flexibility Characteristics in Novice Climbers

Maikey Lopera, John P. Porcari, Jeff Steffen, Scott Doberstein 1and Carl Foster Theories & Applications the International Edition Printed Version: (ISSN 2090-5262) Online Version: (ISSN 2090-5270) March 2011, Volume 1, No. 1 Pages (79 - 91)

The Effect of Indoor Rock Climbing On Strength, Endurance, and Flexibility Characteristics in Novice Climbers Maikey Lopera, John P. Porcari, Jeff Steffen, Scott Doberstein and Carl Foster

Purpose: This study was designed to evaluate changes in muscular strength, endurance, and flexibility in novice climbers following 7 weeks of indoor rock climbing and to determine if these responses are related to improvements in climbing performance. Method: Climbers (CL: n=14) and non-climbers (N-CL: n=10) were assessed before and after the study period. Tests included right and left handgrip and pinch grip strength, lat pull-down strength, arm-hang endurance, handgrip endurance, sit-and-reach flexibility, and total climbing time. The CL group completed a 7-week training protocol involving climbing 5-6 routes on an indoor climbing wall, 2x weekly. Result: The CL group had significant improvements in handgrip strength (7%), pinch strength (9%), handgrip endurance (26%), arm hang time (35%), and climbing performance (50%). There were no significant changes in the N-CL group. There were no significant correlations between improvement in climbing performance and change in muscle strength and endurance within CL. Discussion: The climbing performance of novice climbers can be improved in a relatively short period of time. However, the improvement is most likely due to improved climbing technique, than to improvements in muscular strength and endurance.

Keywords: rock climbing, physical activity, performance

Introduction

T

he popularity of rock climbing has increased considerably in recent years (Booth, Marino, Hill, & Gwinn, 1999; Watts, Newbury, & Sulentic, 1996). Reasons for this increase in popularity include the vast increase of indoor climbing walls throughout the United States, the development of “sport climbing,” and improved safety equipment (Paige, 1998). Additionally, climbing offers several fitness benefits making it a desirable activity (Janot et al., 2000; Wescott, 1992). There is not single factor that can ensure success in the practice of climbing. Characteristics such as strength, endurance, flexibility, technique and psychological control all contribute to rock climbing performance Maikey Lopera a clinical exercise psychologist in the University of Wisconsin-La Crosse Carl Foster, John P. Porcari and Jeff Steffen Department of Exercise and Sport Science, University of Wisconsin-La Crosse, Scott Doberstein is the head athlete trainer at the University of Wisconsin-La Crosse.

(Binney, 2001). Most studies have focused on elite or intermediate climbers (Billat et al. 1995; Booth et al., 1999; Cutts & Bollen, 1993; Grant, Hynes, Whittaker, & Aitchison, 1996; Mermier, Janot, Parker, & Swan, 2000; Mermier, Robergs, McMinn, & Heyward, 1997; Sheel, Seddon, Knight, McKenzie, & DE, 2003; Wall, Starek, Fleck, & Byrnes, 2004; Watts et al., 1996; Watts, Daggett, Gallagher, & Wilkins, 2000; Watts & Drobish, 1998; Watts, Joubert, Lish, Mast, & Wilkins, 2003; Watts, Martin, & Durtschi, 1993), with relative lack of climbing related research targeting novice climbers. A small number of studies have reported significant anthropometric differences between elite/recreational climbers and non-climbers, sugesting small stature, low body mass and low percentage of body fat as traits characterizing elite climbers (Grant et al., 1996; Mermier et al., 2000; Watts et al., 1996; Watts et al., 2000; Watts & Drobish, 1998; Watts et al., 1993). Watts et al. (2003), working with young elite sport rock climbers, reported anthropometric characteristics similar to their adult counterparts.

Maikey Lopera, John P. Porcari, Jeff Steffen, Scott Doberstein 1and Carl Foster

Several studies have suggested that muscular strength and endurance, especially in the forearms, fingers and shoulders, may be significant predictors of climbing performance (Ferguson & Brown, 1997; Grant et al., 1996; Watts et al., 1996; Watts & Drobish, 1998; Watts et al., 1993). An earlier work by Cutts and Bollen (1993) found hand and pinch grip strength and pinch grip endurance to be significantly higher in climbers than nonclimbers. Supporting those findings, Grant et al. (1996) reported that the pull-up and bent arm hang separated the climbers from non-climbers. Studies by Mermier et al. (2000) and Wall et al. (2004) reported high grip strength values in elite female climbers, while Watts et al. (2003) reported similar results in young elite sport rock climbers. Despite these results Giles, Rhodes, & Taunton (2006) noted little correlation between absolute hand grip strength and climbing ability. Climbing related research has generally focused on elite climbers with very few research studies of recreational or novice climbers. Additionally, there is lack of research that measure changes in strength, endurance and flexibility attributable to rock climbing training, especially in novice climbers. A longitudinal study by Wescott (1992), reported “significant improvements in body composition, joint flexibility, muscular strength and cardiovascular endurance” after two months of rock climbing, 15-20 minutes twice a week. A more recent study by Baláš (2005) in the Czech Republic, reported a significant increase in the time of the bent arm hang test and in the number of pull-ups in children after 7 months of climbing activities twice a week. Accordingly, there is a need for more research focusing in novice or beginner climbers, especially longitudinal studies measuring changes in characteristics believed to be important to improve climbing ability. Therefore, the goal of this study was to measure changes in strength, endurance and flexibility in novice climbers after 7 weeks of indoor rock climbing, and to evaluate how these changes were correlated with improvements in climbing performance. Methods

Subjects Twenty-eight college students volunteered to participate in this study and were assigned to one of two groups. The treatment group, novice climbers (CL), consisted of 16 subjects (n=6 male, n=10 female) enrolled in a indoor rock climbing class. The control group, non-climbers (N-CL), consisted of 10 subjects (n=5 male, n=7 female) enrolled in an active lifestyle course. All subjects completed a questionnaire about their previous climbing experience and those with less than two previous climbing encounters were considered for participation in the study. The protocol for this study was approved by the university human subjects committee and subjects provided written informed consent form prior to the study. All subjects healthy based on the Physical Activity Readiness Questionnaire (PAR-Q) given prior to the beginning of the first testing session. Training Protocol Subjects in the CL group were enrolled in 2 days per week, 7-week indoor rock climbing class at the university climbing facility. The duration of each class period was 2 hours. A total of six routes, graded 5.4 to 5.6 on the Yosemite Decimal System (YDS), were used by the CL group for their training program. Prior to the start of the training, subjects were provided an overview of the study, the procedures involved and proper safety and rope handling instructions. Additionally, subjects were provided with instruction on climbing techniques and with climbing specific technique feedback using the verbal performance cues of McNamee and Steffen (McNamee & Steffen, 2007). The training protocol involved climbing 5-6 routes during each class period. Subjects were allowed to climb the routes in any order during the two-hour period. The training protocol was supervised by a rock climbing instructor and the principal investigator. In addition, subjects in the CL group were given a Climbing Record Sheet with a personal climbing questionnaire, an explanation of the protocol to follow, and a climbing record where subjects were required to

Maikey Lopera, John P. Porcari, Jeff Steffen, Scott Doberstein 1and Carl Foster

keep a record of the number of routes climbed per session. Subjects in the N-CL group were asked to maintain their regular daily routine and to avoid climbing or performing exercise routines designed to improve the characteristics that were assessed in the study. Testing Overview Two testing sessions were performed on all subjects. The pre-treatment (PRE) testing session following subject recruitment and before starting the training protocol. The posttreatment (POST) testing session was repeated after the 7-week study period. Subjects on both groups were asked to abstain from any strenuous activity for 24 hours prior to each testing session.

Skinfold thicknesses were measured to the nearest 0.5 mm at seven sites with a Lange skinfold caliper (Cambridge Scientific Industries, Inc. Cambridge, MD), following the procedures described by Maud and Foster (2006). The sites measured were triceps, front thigh, sub-scapular, abdomen, chest, supra-iliac and mid-axilla. Two readings were taking in a rotating order and if they differed by more than 1.0 mm a third measure was taken and an average value was calculated using the three measures. All skinfold thickness measurements were taken on the right with the subject in the standing position. Body density was estimated according to the equations of Jackson and Pollock (Maud & Foster, 2006). Subsequently, % body fat was computed from the estimate of body density with the Siri equation (Wang et al., 1998). 2. Muscular Strength

To avoid inter-tester variability, all testing procedures were performed by the same person in a single session and following the same order for all subjects. The order of the testing was: height, body mass, arm span, skin fold thicknesses, handgrip strength, modified seatand-reach, pinch strength, handgrip endurance, one-repetition maximal lateral pull-down, bentarm hang, climbing performance, foot rise, and leg span tests. To avoid familiarization with the route used for the Climbing Performance Test, the training protocol and climbing performance testing were performed at different locations.. Testing Procedures 1. Anthropometrics Height was measured to the nearest 0.5 cm using a stadiometer. Body mass was measured to the nearest 0.5 kg on a beam scale. Arm span was measured in the standing position against a wall and with the arms abducted horizontally. The greatest tip to tip distance between the extended fingers was measured with a 3.0 m tape measure and recorded in centimeters to the nearest 0.5 cm. “Ape index”, or the ratio of arm span to height, was calculated as arm span divided by height (Watts et al., 2003).

Bilateral maximal handgrip strength was assessed using a Jamar dynamometer (Asimov Engineering Company, Los Angeles, CA) which was adjusted according to the manufacturer’s instructions for each subject. During measurement subjects stood upright with their arms downward to the side and were instructed to apply maximal force for ~2 seconds. Subject were allowed one practice trial on each hand followed by three tests on each hand, alternating between the right and left hand. Measurements were recorded to the nearest pound. Handgrip strength was determined as the average of the three trials for each hand. Pinch strength was measured using the same Jamar dynamometer placed flat on a table (Figure 1). The participant was instructed to hold the crossbars of the dynamometer between the thumb and middle and index finger; the other three fingers were not allowed to be used. Standing upright in front of the table with the arm to be tested extended, the participant then gripped the dynamometer with the thumb and middle and index finger and squeezed with maximum effort for ~ 2 seconds. The participant was given one practice trial on each hand followed by three testing trials, alternating between hands until three values were recorded for each hand.

Maikey Lopera, John P. Porcari, Jeff Steffen, Scott Doberstein 1and Carl Foster

Figure 1. Four common hand positions used in rock climbing: A pocket, B open, C pinch, D crimp. Upper body strength was assessed using onerepetition maximum (1-RM) lateral pull-down test on a Magnum Fitness Systems (Milwaukee, WI) lat pull-down machine. Subjects were allowed to warm-up performing a series of three warm-up sets, 3 repetitions each, on the lat pulldown machine using 45-65% of body weight (self-selected). Following the warm up, subjects performed a single repetition per set against increasing resistance using a front overhand grip on the pull-down bar and legs under the supporting mechanism. There was a one-minute rest between attempts. Failure to complete a pull-down below the chin or failure to maintain proper form was considered an unsuccessful lift. Maximum strength was determined as the highest weight lifted successfully. 3. Muscular Endurance Upper-body isometric muscular endurance was assessed using the bent-arm hang test on an overhead bar. With an overhand grip, participants were instructed to pull-up until a maximally flexed arm position (at the elbow joint) was achieved and then instructed to remain in this position for as long as possible. The test score time was defined as the point at which the participants failed to maintain their chin above the bar. Time was recorded on only one trial. Bilateral handgrip endurance was measured by timing how long the subjects maintained 70% of their maximum voluntary contraction (previously measured with the maximal handgrip strength test) using the same handgrip dynamometer used to assess handgrip and pinch strength. Time measurement started when the subjects reached the target value on the

dynamometer and was stopped when the subjects dropped to a value 5 kg below their target value (70% of their computed maximal handgrip strength). 4. Flexibility A modified sit-and-reach test according to Maud & Foster (2006), was used to evaluate hamstring and low-back flexibility. The subjects were asked to sit on the floor with their back and head against a wall, legs fully extended, with the bottom of the feet against the sit-andreach box. They were then asked, with their hands on top of each other, to stretch their arms forward as far as they can while keeping the head and back against the wall and hold the position for 3 seconds and the distance from the fingertips to the box edge was measured with a ruler. Each subject was allowed three tests and the average of the three scores was computed for analysis. The foot raise test, modified from Grant et al. (1996), was used to evaluate frontal hip flexibility. For this test subjects were required to stand facing a wall with toes touching a line 25 cm from the wall. Both hands were placed on the wall at shoulder height and width. Standing on the left foot without shoes, subjects were asked to bring the right foot directly up. Then, subjects were instructed to place the toe of the right foot as high up the wall as possible without moving it laterally and while keeping the left foot completely flat on the floor. The distance the foot was raised was recorded using a tape measure. The average score of three attempts was computed for analysis. The foot raise test was assessed only on the right leg.

Maikey Lopera, John P. Porcari, Jeff Steffen, Scott Doberstein 1and Carl Foster

The leg span measurement was used to assess lateral hip flexibility. Without shoes, subjects were laid in a supine position and extend their feet as wide apart as possible while keeping the knees straight. Leg span was measured from left to right medial calcaneus using a tape measure (Grant et al., 1996). Three consecutive measurements were recorded and average value was computed for analysis.

wall (lowering and getting back on the route) was ~10 seconds. The climbing performance test score consisted of the total number of points achieved by climbing the wall continuously until volitional failure. The last handhold reached before falling was included to compute each subject score. Also, time in seconds until volitional failure was recorded (Accusplit, San Jose, CA) to assess subjects' climbing time.

5. Climbing Performance Test

Statistical Analysis

The climbing performance test was performed on a specially set route, graded 5.6 on the YDS, on the indoor climbing wall. Each handhold in the climbing performance test route was assigned a specific score, with scores ranging from 5 points (starting handhold) to 250 points (highest handhold). Subjects were not allowed to practice the climbing performance test route between testing sessions to avoid familiarization. Upon arrival to the climbing wall, subjects were provided with climbing shoes and harnesses, and instructed of their proper use. Subjects were secured with a safety rope (top-rope) to prevent injury in case of a fall. Belaying of the subjects during the test was performed by qualified personnel. Subjects who made it to the top of the route were lowered to the beginning and instructed to begin climbing immediately. The time spent off the

Standard descriptive statistics were used to evaluate the characteristics of the CL and N-CL groups. Independent-samples t-test were used to determine if there was significant differences between groups for all pre-test variables. A twoway analysis of variance (ANOVA) with repeated measures was used to compare differences between groups over the course of the study. Least significant difference (LSD) post-hoc tests were used to identify pairwise differences. Pearson product-moment correlations were used to evaluate the relationship between changes in climbing performance (climbing score and climbing time) and those measures that showed a significant pre-post improvement in the CL group. Statistical significance was accepted when p