Journal of Sports Sciences, December 2006; 24(12): 1273 – 1280
A comparison of physiological and anthropometric characteristics among playing positions in sub-elite rugby league players
TIM J. GABBETT Queensland Academy of Sport, Sunnybank, QLD, Australia (Accepted 24 November 2005)
Abstract This study compared the physiological and anthropometric characteristics of specific playing positions and positional playing groups in sub-elite rugby league players. Altogether, 415 sub-elite rugby league players underwent measurements of standard anthropometry (body mass, height, sum of four skinfolds), muscular power (vertical jump), speed (10-m, 20-m, and 40-m sprint), agility (‘‘L’’ run), and estimated maximal aerobic power (multi-stage fitness test). Props were significantly heavier and had a greater skinfold thickness than all other playing positions. Centres, fullbacks, and hookers were faster than props over 40 m. When the data were analysed according to positional commonality, props were taller, heavier, had a greater skinfold thickness, were less agile, and were slower over 10 m than all other positional groups. The hookers/halves and outside backs positional groups were significantly faster over 40 m than the backrowers and props positional groups. In addition, the hookers/halves and outside backs positional groups had significantly greater estimated maximal aerobic power than the props positional group. The results of this study demonstrate that few physiological and anthropometric differences exist among individual playing positions in sub-elite rugby league players, although props are taller, heavier, have greater skinfold thickness, slower 10-m and 40-m speed, less agility, and lower estimated maximal aerobic power than other positional groups. These findings provide normative data for sub-elite rugby league players competing in specific individual positions and positional playing groups.
Keywords: Semi-professional, collision sport, performance, training, football
Introduction Rugby league is a collision sport played in several countries worldwide, including Australia, New Zealand, England, France, Italy, Russia, Romania, Wales, Scotland, Ireland, Papua New Guinea, Fiji, Samoa, and South Africa. In Australia, there are several different rugby league playing levels that can be generally classified as elite (paid professional players), sub-elite (receive moderate remuneration to play rugby league, but also rely on additional employment to generate income), and non-elite (amateur players) (Gabbett, 2001). The game is intermittent in nature, requiring players to compete in a challenging contest, comprising intense bouts of sprinting and tackling, separated by short bouts of lower-intensity activity (recovery) (Gabbett, 2005e). As a result of the physical demands of the game, the physiological qualities of players are highly developed with players requiring high levels of aerobic fitness, speed, muscular power, and agility (Gabbett, 2005e).
Rugby league team positions can be broadly classified as either forwards (i.e. all players involved in the scrum) or backs (i.e. all players not involved in the scrum). Team positions can also be classified according to the specific individual position played (i.e. prop, hooker, second row, lock, half-back, fiveeighth, centre, wing, and fullback), or according to four subgroups reflecting positional commonality (i.e. props, hookers/halves, backrowers, and outside backs) (Meir, Newton, Curtis, Fardell, & Butler, 2001b; O’Connor, 1996). Time – motion studies have shown that rugby league players perform different match-play activities during competition depending on playing position (Meir, Colla, & Milligan, 2001a), with forwards being involved in significantly more physical collisions and tackles than backs (Gissane, White, Kerr, & Jennings, 2001). It is also recognized that the ratio of highintensity activity to low-intensity activity is higher for forwards (1:7 to 1:10) than backs (1:12 to 1:28), with forwards covering a greater distance during a match
Correspondence: T. J. Gabbett, Athlete and Coach Support Services, Queensland Acdemy of Sport, PO Box 956, Sunnybank, QLD 4109, Australia. E-mail:
[email protected] ISSN 0264-0414 print/ISSN 1466-447X online Ó 2006 Taylor & Francis DOI: 10.1080/02640410500497675
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(9929 vs. 8458 m) (Meir et al., 2001a). These findings demonstrate that in rugby league a wide range of skills and physiological demands exist for different playing positions. Comparisons of the physiological and anthropometric characteristics of specific rugby league playing positions are uncommon, as most (Allen, 1989; Baker & Nance, 1999; Brewer, Davis, & Kear, 1994; Clark, 2002; Gabbett, 2000b, 2002a, 2005d; Larder, 1992; Meir, 1993a, 1993b; O’Connor, 1995) but not all (Gabbett, 2002b, 2005a; Gabbett & Herzig, 2004; Meir et al., 2001b; O’Connor, 1996) studies have used small sample sizes. Previous studies of the physiological and anthropometric characteristics of elite rugby league players have reported significant differences among playing positions for height (O’Connor, 1996), body mass (Meir et al., 2001b; O’Connor, 1996), skinfold thickness (Meir et al., 2001b; O’Connor, 1996), maximal aerobic power (O’Connor, 1996), speed (Clark, 2002; Meir et al., 2001b; O’Connor, 1996), repeated sprint ability (Clark, 2002), and muscular strength (Meir et al., 2001b; O’Connor, 1996). However, while differences have been reported among playing positions for elite rugby league players, no study has investigated whether similar physiological and anthropometric differences exist among playing positions in sub-elite rugby league. Consequently, normative data for sub-elite rugby league players do not exist, making the development of realistic position-specific performance standards difficult. In addition, the development of physical performance standards for individual playing positions and positional playing groups would allow coaches to identify player weaknesses and develop specific training programmes for players according to their position (Meir, 1993a). With this in mind, the aim of the present study was to compare the physiological and anthropometric characteristics of specific playing positions and positional playing groups in sub-elite rugby league. It was hypothesized that the physiological and anthropometric characteristics of sub-elite rugby league players would differ significantly among individual playing positions and positional playing groups.
Methods Participants Altogether, 415 healthy men participated in this study. Players were participants from ten teams competing within the Gold Coast Group 18 (New South Wales Rugby League, Australia) senior rugby league competition. The players in the present study were defined as sub-elite as they were receiving moderate remuneration to play, but were also relying
on additional employment to generate income (Gabbett, 2001). In addition, although the players competed with the goal of reaching and winning the grand final, the senior rugby league competition could be described as a sub-elite competition. All participants received a clear explanation of the study, including the risks and benefits of participation, and written consent was obtained. The Institutional Review Board for Human Investigation approved all experimental procedures. Procedure The rugby league season lasted from December through to September, with matches played from February through to September. Players performed two 90-min training sessions each week. All fitness testing was conducted over a 3-week period during the competitive phase of the season (May), after players had obtained a degree of match fitness. Fitness testing was conducted on the Tuesday and Wednesday, at least 2 days after participating in a match. The coaches of the various teams stated that they were prepared to devote one training session (approximately 90 min) to the field testing. Although consideration was given to the specificity of the field test, the selection of tests was influenced by this time constraint. Fitness tests Standard anthropometry (height, body mass, sum of four skinfolds) (Norton et al., 2000), muscular power (vertical jump: Gabbett, 2002b), speed (10-m, 20-m, and 40-m sprints: O’Connor, 1996), agility (‘‘L run’’; Webb & Lander, 1983), and estimated maximal aerobic power (multi-stage fitness test: Ramsbottom, Brewer, & Williams, 1988) were the fitness tests selected. The participants were instructed to refrain from strenuous exercise for at least 48 h before the fitness test session, and to consume their normal pre-training diet before the test session. The test session began with anthropometric measurements. Players were then randomly allocated into three groups, consisting of approximately equal numbers. Players in group one underwent measurements of muscular power (vertical jump), while players in groups two and three underwent agility (‘‘L run’’) and speed (10-m, 20-m, and 40-m sprints) measurements respectively. Players performed two trials for the speed, agility, and muscular power tests, with a recovery of approximately 3 min between trials. Players were encouraged to perform low-intensity activities and stretches between trials. Upon completion of the respective tests, each group rotated until all tests had been performed. The field test session concluded with
Fitness and playing position in rugby league players performing the multi-stage fitness test (estimated maximal aerobic power). Anthropometry Body mass and excess body fat have been shown to have a negative influence on performance (e.g. power to body mass ratio, thermoregulation, and aerobic capacity) (Meir et al., 2001b). As an estimate of adiposity, skinfold thickness was measured at four sites using a Harpenden skinfold caliper. Biceps, triceps, subscapular, and suprailiac were the four sites selected. The exact positioning of each skinfold measurement was in accordance with procedures described by Norton et al. (2000). Skinfold thickness was measured to the nearest 0.1 mm, with the average score obtained from two measurements being recorded. Height was measured using a portable stadiometer, and body mass was measured using calibrated digital scales (A&D Co. Ltd, Tokyo, Japan). The intraclass correlation coefficient for test – retest reliability and the typical error of measurement (Hopkins, 2000) for height, body mass, and sum of four skinfolds were 0.99, 0.99, and 0.99, and 0.2%, 0.8%, and 3.0%, respectively.
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Speed Rugby league players need to move quickly to position themselves in attack and defence (Meir et al., 2001b). However, time – motion studies have shown that rugby league players are rarely required to sprint distances more than 40 m in a single bout of intense activity (Meir et al., 2001a). The running speed of players was evaluated in 10-m, 20-m, and 40-m sprints (O’Connor, 1996) using dual beam electronic timing gates (Swift Performance Equipment, NSW, Australia). The timing gates were positioned 10, 20, and 40 m cross-wind from a pre-determined starting point. Players were instructed to run as quickly as possible along the 40m distance from a standing start (Brewer et al., 1994). All tests were conducted outdoors, in dry conditions, on a well-grassed surface. Speed was measured to the nearest 0.01 s with the fastest value obtained from two trials being recorded. The intraclass correlation coefficient for test – retest reliability and typical error of measurement (Hopkins, 2000) for the 10-m, 20-m, and 40-m sprints were 0.95, 0.97, and 0.97, and 1.8%, 1.3%, and 1.2%, respectively. Agility
Muscular power The ability to generate high muscular power is an important attribute of rugby league players. Players are required to have high muscular power to perform the tackling, lifting, pushing, and pulling tasks that occur during a match (Meir et al., 2001b). In addition, high muscular power is required to provide fast play-the-ball speed and leg drive in tackles (Gabbett, 2005b). Lower body muscular power was estimated by means of the vertical jump test (Gabbett, 2002b) using a Yardstick vertical jump device (Swift Performance Equipment, NSW, Australia). Players were requested to stand with feet flat on the ground, extend their arm and hand, and mark the standing reach height. After assuming a crouch position, each participant was instructed to spring upward and touch the Yardstick device at the highest possible point. No specific instructions were given regarding the depth or speed of the countermovement. Vertical jump height was calculated as the distance from the highest point reached during standing and the highest point reached during the vertical jump. Vertical jump height was measured to the nearest centimetre with the highest value obtained from two trials being recorded. The intraclass correlation coefficient for test – retest reliability and typical error of measurement (Hopkins, 2000) for the vertical jump test were 0.96 and 3.3%, respectively.
Rugby league players are required to rapidly accelerate, decelerate, and change direction (Meir et al., 2001b). The agility of players was evaluated using an ‘‘L run’’ (Webb & Lander, 1983) using dual beam electronic timing gates (Swift Performance Equipment, NSW, Australia). The ‘‘L-run’’ requires players to change direction laterally, and based on time – motion studies (Meir et al., 1993) it has been suggested to reflect the movement patterns of rugby league. Three cones, approximately 1 m in height, were placed 5 m apart in the shape of an ‘‘L’’. Players ran forward 5 m, turned to their left, ran forward 5 m, turned 1808, and followed the same course to return to the finish line. Players were instructed to run as quickly as possible over the agility run. Agility times were measured to the nearest 0.01 s with the fastest value obtained from two trials being recorded. The intraclass correlation coefficient for test – retest reliability and typical error of measurement (Hopkins, 2000) for the ‘‘L run’’ were 0.90 and 2.8%, respectively. All tests were conducted outdoors, in dry conditions, on a wellgrassed surface. Maximal aerobic power Depending on the level of competition, rugby league matches last 60 – 80 min, with players covering 8458 – 9929 m in a match (Meir et al., 2001a).
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Players also require high aerobic fitness to aid recovery after high-intensity bouts of activity. Maximal aerobic power was estimated using the multistage fitness test (Ramsbottom et al., 1988). Players were required to run back and forth (i.e. shuttle run) along a 20-m track, keeping in time with a series of signals on a compact disc. The frequency of the audible signals (and hence running speed) was progressively increased, until the participants reached volitional exhaustion. Maximal aerobic power (V_ O2max) was estimated using regression equations described by Ramsbottom et al. (1988). It has been demonstrated that, compared with treadmilldetermined V_ O2max, the multi-stage fitness test provides a valid estimate of maximal aerobic power (Ramsbottom et al., 1988). In addition, in a previous study (Gabbett, 2005b) rugby league players completed duplicate multi-stage fitness tests, performed one week apart, to determine test – retest reliability. The intraclass correlation coefficient for test – retest reliability and typical error of measurement (Hopkins, 2000) for the multi-stage fitness test were 0.90 and 3.1%, respectively. All tests were conducted outdoors, in dry conditions, on a well-grassed surface. Statistical analysis Data were collected from 215 forwards (59 props, 55 hookers, 69 second-rowers, 32 locks) and 200 backs (21 half-backs, 25 five-eighths, 60 centres, 60 wingers, 34 fullbacks). The hookers/halves positional group consisted of hookers, half-backs, and fiveeighths. The backrowers positional group consisted of second-rowers and locks, while the outside backs positional group consisted of centres, wingers, and fullbacks. The total number of players in the props, hookers/halves, backrowers, and outside backs positional groups was 59, 101, 101, and
154, respectively. Differences in anthropometric characteristics, vertical jump height, speed, agility, and estimated V_ O2max of the different playing positions and positional groups were compared using a one-way analysis of variance. When required, comparisons of group means were performed using Scheffe´’s post-hoc test. Statistical significance was set at P 5 0.05 and all data are reported as means + standard deviations.
Results Anthropometric characteristics The mean (+s) age and playing experience of all players were 22.3 + 5.0 and 13.1 + 7.3 years, respectively. The mean (+s) height, body mass, and sum of four skinfolds for all players were 1.77 + 0.07 m, 85.8 + 13.3 kg, and 43.7 + 16.8 mm, respectively. Significant differences (P 5 0.05) were detected among individual positions for height, body mass, and skinfold thickness. Props were heavier (P 5 0.05) and had a greater skinfold thickness (P 5 0.05) than all other positions. In addition, props were taller (P 5 0.05) than all positions except lock and fullback. Hookers were shorter (P 5 0.05) than locks (Table I). When the data were analysed according to positional commonality, props as a positional group were taller, heavier, and had a greater skinfold thickness (all P 5 0.05) than all other positional groups. Backrowers were taller (P 5 0.05) and heavier (P 5 0.05) than the hookers/halves positional group. In addition, hookers/ halves were shorter (P 5 0.05) than outside backs (Table II). Physiological characteristics The mean (+s) vertical jump height and agility of all players were 46.9 + 10.5 cm and 6.02 + 0.55 s,
Table I. Anthropometric characteristics of specific individual rugby league positions (mean + s).
Prop Hooker Second row Lock Half-back Five-eighth Centre Wing Fullback
Age (years)
Playing experience (years)
Height (m)
Body mass (kg)
Sum of skinfolds (mm)
21.7 + 4.5 21.2 + 4.2 24.0 + 5.6 25.7 + 5.6e 21.2 + 4.7 23.7 + 6.1 21.1 + 3.4 21.1 + 4.6 21.4 + 5.8
11.9 + 7.9 15.1 + 5.7 14.1 + 8.6 16.5 + 8.4 13.4 + 5.4 17.1 + 8.0d 11.2 + 4.6 10.0 + 6.5 12.0 + 5.8
1.85 + 0.06 1.72 + 0.03af 1.77 + 0.06a 1.80 + 0.06 1.74 + 0.08a 1.75 + 0.04a 1.76 + 0.03a 1.77 + 0.08a 1.78 + 0.06
105.6 + 8.9 75.5 + 9.4ab 90.2 + 8.9acd 87.0 + 9.0ad 76.3 + 10.0a 83.3 + 12.6a 84.3 + 9.6a 76.5 + 7.8a 82.2 + 10.6a
67.7 + 18.4 37.1 + 12.0a 44.5 + 12.6a 40.1 + 11.6a 39.8 + 10.1a 39.7 + 16.9a 40.3 + 13.9a 32.6 + 13.2a 42.6 + 14.7a
a Significantly different (P 5 0.05) from prop. bSignificantly different (P 5 0.05) from second row, lock, and centre. cSignificantly different (P 5 0.05) from half-back. dSignificantly different (P 5 0.05) from wing. eSignificantly different (P 5 0.05) from centre. fSignificantly different (P 5 0.05) from lock. Prop, n ¼ 59; hooker, n ¼ 55; second row, n ¼ 69; lock, n ¼ 32; half-back, n ¼ 21; five-eighth, n ¼ 25; centre, n ¼ 60; wing, n ¼ 60; fullback, n ¼ 34.
Fitness and playing position in rugby league respectively. The mean (+s) 10-m speed, 40-m speed, and estimated V_ O2max of all players were 2.13 + 0.26 s, 5.97 + 0.42 s, and 45.5 + 6.5 ml kg71 min71, respectively. There were no significant differences (P 4 0.05) among individual positions for 10-m speed. However, centres, fullbacks, and hookers were faster than props over 40 m. Hookers were the most agile (Table III). When the data were analysed according to positional commonality, props as a positional group were less agile and were slower over 10 m (P 5 0.05) than all other positional groups. The hookers/halves and outside backs positional group was faster over 40 m (P 5 0.05) than the backrowers and props positional group. In addition, hookers/halves and outside backs had a higher estimated V_ O2max (P 5 0.05) than the props positional group (Table IV).
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Discussion Although several studies have examined the physiological and anthropometric characteristics of rugby league players, few have documented the influence of playing position on the fitness of these athletes. Previous studies of the physiological and anthropometric characteristics of elite rugby league players have shown significant differences among playing positions for height (O’Connor, 1996), body mass (Meir et al., 2001b; O’Connor, 1996), skinfold thickness (Meir et al., 2001b; O’Connor, 1996), estimated V_ O2max (O’Connor, 1996), speed (Meir et al., 2001b; O’Connor, 1996), repeated sprint ability (Clark, 2002), and muscular strength (Meir et al., 2001b; O’Connor, 1996). The present study is the first to compare the physiological and
Table II. Anthropometric characteristics of rugby league positional groups (mean + s).
Props Hookers/halves Backrowers Outside backs
Age (years)
Playing experience (years)
Height (m)
Body mass (kg)
Sum of skinfolds (mm)
21.7 + 4.5 21.8 + 4.9 24.5 + 5.6abc 21.2 + 4.4
11.9 + 7.9 15.4 + 6.5 14.9 + 8.5c 10.9 + 5.6b
1.85 + 0.06 1.73 + 0.05ac 1.78 + 0.06ab 1.77 + 0.06a
105.6 + 8.9 77.8 + 10.9a 89.3 + 9.0ab 80.8 + 9.8a
67.7 + 18.4 38.4 + 12.8a 43.1 + 12.4a 38.4 + 14.2a
Significantly different (P 5 0.05) from props positional group. bSignificantly different (P 5 0.05) from hookers/halves positional group. Significantly different (P 5 0.05) from outside backs positional group. Props, n ¼ 59; hookers/halves, n ¼ 101; backrowers, n ¼ 101; outside Backs, n ¼ 154. a
c
Table III. Physiological characteristics of specific individual rugby league positions (mean + s).
Prop Hooker Second row Lock Half-back Five-eighth Centre Wing Fullback
10 m (s)
20 m (s)
40 m (s)
Agility (s)
Vertical jump (cm)
V_ O2max (ml kg71 min71)
2.18 + 0.23 2.06 + 0.23 2.19 + 0.32 2.11 + 0.31 2.09 + 0.23 2.08 + 0.20 2.08 + 0.21 2.14 + 0.28 2.16 + 0.24
3.55 + 0.23 3.38 + 0.26 3.44 + 0.30 3.36 + 0.27 3.35 + 0.24 3.36 + 0.19 3.33 + 0.19a 3.39 + 0.28 3.33 + 0.25
6.21 + 0.38 5.88 + 0.34a 6.13 + 0.49b 5.96 + 0.52 5.89 + 0.37 5.91 + 0.31 5.81 + 0.30a 5.89 + 0.41 5.84 + 0.39a
6.36 + 0.48 5.83 + 0.60a 6.11 + 0.60 5.84 + 0.47 5.93 + 0.47 6.16 + 0.64 5.94 + 0.44 5.96 + 0.54 5.89 + 0.50
43.4 + 9.0 50.9 + 10.5 45.7 + 10.5 46.6 + 12.4 48.4 + 9.0 41.0 + 7.7 50.0 + 8.8 46.5 + 12.0 47.4 + 11.9
42.6 + 6.5 46.7 + 7.0 44.4 + 6.9 46.1 + 5.4 47.3 + 6.2 45.5 + 5.3 46.6 + 6.2 45.2 + 6.7 47.0 + 5.8
a
Significantly different (P 5 0.05) from prop. bSignificantly different (P 5 0.05) from centre. Prop, n ¼ 59; hooker, n ¼ 55; second row, n ¼ 69; lock, n ¼ 32; half-back, n ¼ 21; five-eighth, n ¼ 25; centre, n ¼ 60; wing, n ¼ 60; fullback, n ¼ 34.
Table IV. Physiological characteristics of rugby league positional groups (mean + s).
Prop Hookers/halves Backrowers Outside backs
10 m (s)
20 m (s)
40 m (s)
Agility (s)
Vertical jump (cm)
V_ O2max (ml kg71 min71)
2.18 + 0.23 2.07 + 0.22a 2.17 + 0.32a 2.12 + 0.25a
3.55 + 0.23 3.37 + 0.24 3.41 + 0.29 3.35 + 0.24
6.21 + 0.38 5.89 + 0.33a 6.08 + 0.50bc 5.85 + 0.36a
6.36 + 0.48 5.93 + 0.59a 6.02 + 0.58a 5.94 + 0.49a
43.4 + 9.0 47.7 + 10.3 46.0 + 11.1 48.3 + 10.6
42.6 + 6.5 46.5 + 6.4a 44.9 + 6.5 46.1 + 6.3a
Significantly different (P 5 0.05) from props positional group. bSignificantly different (P 5 0.05) from hookers/halves positional group. Significantly different (P 5 0.05) from outside backs positional group. Props, n ¼ 59; hookers/halves, n ¼ 101; backrowers, n ¼ 101; outside backs, n ¼ 154. a
c
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anthropometric characteristics of specific playing positions and positional playing groups in sub-elite rugby league. The results of this study demonstrate that few physiological and anthropometric differences exist among individual playing positions in sub-elite rugby league players, although props are taller, heavier, have a greater skinfold thickness, lower 10-m and 40-m speed, less agility, and lower estimated maximal aerobic power than other positional playing groups. The present study is the largest study of the physiological and anthropometric characteristics of rugby league players. The sample of 415 players compares favourably with the studies of O’Connor (1996: n ¼ 260), Gabbett (2002b: n ¼ 159), Gabbett and Herzig (2004: n ¼ 151), and Meir et al. (2001b: n ¼ 146). The physiological characteristics of the sub-elite rugby league players in this study are better than those previously reported for non-elite rugby league players (Gabbett, 2000b), and are comparable with other sub-elite rugby league players (Gabbett, 2002b, 2005b). Furthermore, the vertical jump, 10m speed, 40-m speed, and estimated V_ O2max results of the sub-elite rugby league players in this study are similar to those reported previously for semi-professional rugby league players (Gabbett, 2002a). The results of this study provide normative data for subelite rugby league players competing in specific individual positions and positional playing groups. In addition, given the large sample size, and the inclusion of winning and losing teams, these data provide a good representation of the physiological and anthropometric characteristics of sub-elite rugby league players. Consistent with previous results from elite rugby league players (Meir et al., 2001b; O’Connor, 1996), the present study found that props were taller, heavier, and had a greater skinfold thickness than other individual positions and positional groups (Tables I and II). These results are also in partial agreement with previous studies that found that body mass successfully predicts selection as a forward or back (Gabbett, 2002a, 2002b). Props spend a large proportion of match-play involved in tackling and physical collisions. As a result, the higher body mass of props may assist in the development of greater momentum and impact forces associated with these activities. The higher body mass would also reduce the likelihood of opposing players effecting tackles on these players (O’Connor, 1996). However, while an increased skinfold thickness has been suggested to provide a protective role against the high numbers of physical collisions sustained by props (Meir, 1993b), the higher body fat component of props may increase the physiological demands placed on them, as they are required to support this weight during an 80-min match, and diminish the ability to dissipate
heat during intense physical activity (Meir et al., 2001b). The present study found that 10-m speed and 40m speed were significantly lower in props than in hookers, centres, and wingers (Table III). In addition, the props positional group was significantly slower than the hookers/halves, backrowers, and outside backs positional groups (Table IV). These findings are in agreement with O’Connor (1996), who found that elite rugby league props had significantly slower 10-m and 40-m speed than outside backs. Previous studies have reported similar 10-m sprint times between forwards and backs, with backs having significantly faster 20-m and 40-m speeds than forwards (Brewer et al., 1994; Gabbett, 2000b). These findings have been attributed to the rare requirement of forwards to run further than 10 m in a single bout of intense activity (Meir, 1993a). However, the faster 10-m sprint times in the hookers/halves, backrowers, and outside backs positional groups appears to reflect a better developed sprinting ability in these players. An interesting finding of this study was that wingers had similar speed as all other playing positions. Results from elite rugby league studies have shown that wingers are traditionally the fastest players on the rugby league team and use their speed to either chase attacking players or to attack while running with the ball (Meir et al., 2001b). Indeed, previous studies of elite rugby league players have shown that wingers have faster 15-m speed than props, and faster 40-m speed than props, secondrowers, locks, half-backs, and five-eighths (Meir et al., 2001b). These findings suggest a greater requirement for acceleration and maximum speed in elite rugby league wingers. The finding from this study that wingers had similar speed to other playing positions may reflect differences in coaching philosophies between elite and sub-elite competition, with faster players selected into other key positional roles, such as centre, fullback, or hooker. Indeed, in the present study, the centres, fullbacks, and hookers had faster 40-m speeds than all other playing positions. Given the slower speed of wingers in the present study, and that these players are required to run at maximum speed over distances of 20 – 60 m (Meir et al., 2001b), coaches should consider grouping wingers with fullbacks and centres when devising specific speed development training programmes (Meir et al., 2001b). The present study found that the hookers/halves and outside backs positional groups had greater estimated V_ O2max than the props positional group (Table IV). These findings are in agreement with O’Connor (1996), who found higher estimated V_ O2max in hookers (55.2 ml kg71 min71), halves (52.0 ml kg71 min71), and outside backs
Fitness and playing position in rugby league (52.8 ml kg71 min71) than in props (48.6 ml kg71 min71). Furthermore, the finding of lower aerobic fitness in props is in line with Meir et al. (2001b), who reported greater distance run in 5 min for hookers and halfbacks (1353 m) than props and second-rowers (1264 m). Despite finding significant differences among positional playing groups in the present study, no significant differences were detected among individual playing positions for estimated V_ O2max. These findings suggest that when training for position-specific improvements in aerobic fitness, players should be grouped according to positional playing group (i.e. props, hookers/halves, backrowers, and outside backs), rather than specific individual positions (Meir et al., 2001b). A high aerobic fitness is required in rugby league, as players have been reported to cover between 8458 and 9929 m per match, with forwards covering a greater total distances than backs (Meir et al., 2001a). The higher estimated V_ O2max in hookers/halves may reflect their high work rate throughout a match. Indeed, time – motion studies have shown that hookers cover a greater total distance during the course of a match than players in any other position (Meir et al., 2001a). Furthermore, hookers defend in the middle of the ruck, and play an important role in following each play-the-ball (Meir et al., 2001b), distributing the ball to support players, and supporting the ball-carrier in attack. A high aerobic fitness is also of particular importance to props given their greater involvement in tackles and physical collisions (Gissane et al., 2001), and the higher intensity of match-play in this position (Meir et al., 2001a). In addition, it has been reported that player fatigue (Gabbett, 2000a) and a low estimated V_ O2max (Gabbett & Domrow, 2005) are risk factors for injuries in rugby league players, with props demonstrating the greatest susceptibility to fatigue-related injuries (Gabbett, 2005c). Clearly, sub-elite rugby league props could benefit from additional aerobic training to enhance performance and reduce the incidence of injury associated with this position. The finding of similar vertical jump height among individual positions and positional playing groups is in agreement with O’Connor (1996), who reported similar vertical jump performance among elite rugby league props, backrowers, outside backs, and hookers/halves. These findings are also in agreement with Meir et al. (2001b), who found similar lower body muscular strength among playing positions and positional groups in elite rugby league players, and Gabbett (2000b, 2002a, 2002b), who found similar vertical jump scores between forwards and backs competing at the sub-elite level. The ability to generate high muscular force rapidly is an important attribute of rugby league players. Players are required to have high muscular strength and power to perform
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the tackling, lifting, pushing, and pulling tasks that occur during a match (Meir et al., 2001b). In addition, high muscular strength and power contribute to running speed, and are required to provide fast play-the-ball speed and leg drive in tackles (Gabbett, 2005b). The finding of similar vertical jump scores among positions suggests that muscular power is an equally important characteristic for all playing positions. However, while muscular power is an important characteristic for all playing positions, it has been suggested that because props work over shorter distances (approximately 10 m) (Meir et al., 2001b), they require a greater ability to generate large forces rapidly (O’Connor, 1996). It is possible that the similar vertical jump scores between props and other playing positions reflects the greater skinfold thickness of props and an attenuation of the power to body mass ratio in these players (Gabbett, 2000b). In conclusion, this study compared the physiological and anthropometric characteristics of specific playing positions and positional playing groups in sub-elite rugby league. The results of this study demonstrate that few physiological and anthropometric differences exist among individual playing positions in sub-elite rugby league, although props are taller, heavier, have a greater skinfold thickness, lower 10-m and 40-m speeds, less agility, and a lower estimated maximal aerobic power than other positional playing groups. These findings provide normative data for sub-elite rugby league players competing in specific individual positions and positional playing groups. References Allen, G. D. (1989). Physiological and metabolic changes with six weeks detraining. Australian Journal of Science and Medicine in Sport, 21, 4 – 9. Baker, D., & Nance, S. (1999). The relation between running speed and measures of strength and power in professional rugby league players. Journal of Strength and Conditioning Research, 13, 230 – 235. Brewer, J., Davis, J., & Kear, J. (1994). A comparison of the physiological characteristics of rugby league forwards and backs. Journal of Sports Sciences, 12, 158. Clark, L. (2002). A comparison of the speed characteristics of elite rugby league players by grade and position. Strength and Conditioning Coach, 10, 2 – 12. Gabbett, T. J. (2000a). Incidence, site, and nature of injuries in amateur rugby league over three consecutive seasons. British Journal of Sports Medicine, 34, 98 – 103. Gabbett, T. J. (2000b). Physiological and anthropometric characteristics of amateur rugby league players. British Journal of Sports Medicine, 34, 303 – 307. Gabbett, T. J. (2001). Severity and cost of injuries in amateur rugby league: A case study. Journal of Sports Sciences, 19, 341 – 347. Gabbett, T. J. (2002a). Influence of physiological characteristics on selection in a semi-professional rugby league team: A case study. Journal of Sports Sciences, 20, 399 – 405.
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Gabbett, T. J. (2002b). Physiological characteristics of junior and senior rugby league players. British Journal of Sports Medicine, 36, 334 – 339. Gabbett, T. J. (2005a). A comparison of physiological and anthropometric characteristics among playing positions in junior rugby league players. British Journal of Sports Medicine, 39, 675 – 680. Gabbett, T. J. (2005b). Changes in physiological and anthropometric characteristics of rugby league players during a competitive season. Journal of Strength and Conditioning Research, 19, 400 – 408. Gabbett, T. J. (2005c). Influence of playing position on the site, nature, and cause of rugby league injuries. Journal of Strength and Conditioning Research, 19, 749 – 755. Gabbett, T. J. (2005d). Physiological and anthropometric characteristics of junior rugby league players over a competitive season. Journal of Strength and Conditioning Research, 19, 764 – 771. Gabbett, T. J. (2005e). Science of rugby league football: A review. Journal of Sports Sciences, 23, 961 – 976. Gabbett, T. J., & Domrow, N. (2005). Risk factors for injury in sub-elite rugby league players. American Journal of Sports Medicine, 33, 428 – 434. Gabbett, T. J., & Herzig, P. J. (2004). Physiological characteristics of junior elite and sub-elite rugby league players. Strength and Conditioning Coach, 12, 19 – 24. Gissane, C., White, J., Kerr, K., & Jennings, D. (2001). Physical collisions in professional super league: The demands of different player positions. Cleveland Medical Journal, 4, 137 – 146. Hopkins, W. G. (2000). Measures of reliability in sports medicine and science. Sports Medicine, 30, 1 – 15. Larder, P. (1992). The rugby league coaching manual (2nd edn.). London: Kingswood Press.
Meir, R. (1993a). Evaluating players’ fitness in professional rugby league: Reducing subjectivity. Strength and Conditioning Coach, 1, 11 – 17. Meir, R. (1993b). Seasonal changes in estimates of body composition in professional rugby league players. Sport Health, 11, 27 – 31. Meir, R., Arthur, D., & Forrest, M. (1993). Time and motion analysis of professional rugby league: A case study. Strength and Conditioning Coach, 1, 24 – 29. Meir, R., Colla, P., & Milligan, C. (2001a). Impact of the 10meter rule change on professional rugby league: Implications for training. Strength and Conditioning Journal, 23, 42 – 46. Meir, R., Newton, R., Curtis, E., Fardell, M., & Butler, B (2001b). Physical fitness qualities of professional rugby league football players: Determination of positional differences. Journal of Strength and Conditioning Research, 15, 450 – 458. Norton, K., Marfell-Jones, M., Whittingham, N., Kerr, D., Carter, L., Saddington, K. et al. (2000). Anthropometric assessment protocols. In C. J. Gore (Ed.), Physiological tests for elite athletes (pp. 66 – 85). Champaign, IL: Human Kinetics. O’Connor, D. (1995). Fitness profile of professional rugby league players. Journal of Sports Sciences, 13, 505. O’Connor, D. (1996). Physiological characteristics of professional rugby league players. Strength and Conditioning Coach, 4, 21 – 26. Ramsbottom, R., Brewer, J., & Williams, C. (1988). A progressive shuttle run test to estimate maximal oxygen uptake. British Journal of Sports Medicine, 22, 141 – 144. Webb, P., & Lander, J. (1983). An economical fitness testing battery for high school and college rugby teams. Sports Coach, 7, 44 – 46.
