Secondary Logo

Journal Logo

Running Demands and Heart Rate Responses in Men Rugby Sevens

Suarez-Arrones, Luis J.; Nuñez, Francisco J.; Portillo, Javier; Mendez-Villanueva, Alberto

Journal of Strength and Conditioning Research: November 2012 - Volume 26 - Issue 11 - p 3155–3159
doi: 10.1519/JSC.0b013e318243fff7
Research Note
Free

Suarez-Arrones, LJ, Nuñez, FJ, Portillo, J, and Mendez-Villanueva, A. Running demands and heart rate responses in men rugby sevens. J Strength Cond Res 26(11): 3155–3159, 2012—The purpose of this study was to examine match running performance and exercise intensity in a Rugby Sevens (7s) team during competitive club-level matches. Time-motion analyses (global position system) were performed on 7 male rugby players during 5 competitive matches in a 2-day tournament. The players covered an average distance of 1,580.8 ± 146.3 m per game (14 minutes). Over this distance, 34.8% (549.7 ± 79.1 m) was spent standing and walking, 26.2% (414.8 ± 105.1 m) jogging, 9.8% (154.6 ± 53.5 m) cruising, 15.5% (244.5 ± 80.1 m) striding, 5% (79.5 ± 37.2 m) high-intensity running, and 8.7% (137.7 ± 84.9 m) sprinting. The average maximal distance of sprints, the number of sprints, the minimum distance of sprint, and the mean sprint distance over the game were 29.5 ± 11.7 m, 7.4 ± 3.9 sprints, 9.1 ± 5.7 m, and 18 ± 7.6 m, respectively. The player's work-to-rest ratio was 1:0.5. For over 75% of the game, the players were exposed to heart rates (HRs) >80% of their maximal HR. There were no statistical differences between the first and second halves in any of the variables analyzed. This study indicates that the physical demands of Rugby 7s are quite different from those encountered in other rugby codes and that the training regimes need to meet the increased overall running demands, the augmented high-intensity running actions, and the reduced work-to-rest ratios.

1Faculty of Sport, Pablo de Olavide University, Sevilla, Spain

2VF Sport, Sevilla, Spain

3Faculty of Sport Science, Toledo, Spain

4Spanish Rugby Federation, Madrid, Spain

5Physiology Unit, Sport Science Department, ASPIRE, Academy for Sports Excellence, Doha, Qatar

Address correspondence to Alberto Mendez-Villanueva, amendezvillanueva@yahoo.com.

Back to Top | Article Outline

Introduction

Rugby is a contact, team sport made up of different codes such as rugby union, rugby league or rugby sevens (7s). The rugby union and rugby league matches have a duration of 80 minutes (2 halves of 40 minutes) and are played by 15 and 13 players, respectively. In rugby 7s, matches last 14 minutes (2 halves of 7 minutes) and are played by teams consisting of 7 members on a pitch of the same dimensions as the rugby union and under similar laws. The final scores are similar to those of rugby union because the marks are made more often. Recently, the rugby 7s has been voted one of the new Olympic summer sports and will appear in Rio 2016 (9), being this code one of the fastest growing sports.

Although research has established that in all rugby codes the game is characterized by periods of high-intensity intermittent exercise such as sprints, high-intensity running, tackles, or rucks, which are intercalated with periods of low-intensity and rest (10,15), only 1 study (17) has examined the physical demands on players during rugby 7s matches. However, the results of this study are difficult to interpret because the activity profile categorization was based on qualitative criteria (17). Accordingly, the aim of this study was to examine for the first time the match running demands and exercise intensity associated with men's rugby 7s with global position system (GPS) technology.

Back to Top | Article Outline

Methods

Experimental Approach to the Problem

In this investigation, an observational design was used to examine the match running demands and exercise intensity during a men rugby 7s competitive tournament. Seven highly trained players were investigated during 5 competitive club-level matches in the final rounds of the national championship. The tournament investigated was contested in June at the end of Rugby 7s competitive season. All the players belonged to the same team that competed at the highest level in the national league. Portable GPS technology and heart rate (HR) responses were used to assess match running demands and exercise intensity, respectively. Identification of player movement patterns and the associated physiological responses during match play is important for optimizing training prescription and managing player preparation for competition.

Back to Top | Article Outline

Subjects

Time-motion analysis of running activity was collected from 7 highly trained men rugby 7s players (age, 27.4 ± 1.6 years; body mass, 87.9 ± 11.0 kg; height, 180.4 ± 7.8 cm; V[Combining Dot Above]O2max, 51.6 ± 3.7 ml·kg−1·min−1; 61.6 ± 6.0 ∑ skinfolds; mean ± SD). All the players participated on average in 13 hours of combined rugby (4 sessions), strength (3 sessions), and conditioning (1–2 sessions) training and competitive play (4–5 rugby 7s games) per week. All the players had a minimum of 5 years of rugby-specific training. Written informed consent was obtained from the players before the investigation. The experimental protocol was approved by the Institutional Ethics Committee.

Back to Top | Article Outline

Experimental Procedures

Match analyses were performed 2–3 times on each player during a total of 5 club-level matches played over a period of 2 days during the national championship finals. All the matches were played on the same standard outdoor natural grass fields with 7 players per side. Playing time was 2 halves of 7 minutes each. All the players were provided with preexercise and postexercise nutrition and hydration plan developed by the medical staff to ensure adequate nutrient and fluid intake before and between all the matches. Four weeks before the tournament, the players undertook an incremental treadmill test. Pulmonary gas exchange (Oxycon Delta de Jaeger, Hoechberg, Germany) and HR (Polar Team System, Polar Electro Oy, Kempele, Finland) were continuously recorded during the test to determine maximal oxygen uptake (V[Combining Dot Above]O2max) and maximal HR (HRmax). The protocol began with a 4 minutes of running speed at 8 km·h−1 followed by stepwise 1-km·h−1 speed increments every 1 minutes until exhaustion. The V[Combining Dot Above]O2max was defined as the highest 30-second average recorded during the incremental treadmill test. The HRmax was defined as the highest 5-second average recorded during the incremental treadmill test.

Back to Top | Article Outline

Activity Pattern Measurements

A GPS unit capturing data at 1 Hz (SPI Elite, GPSports, Canberra, Australia) was fitted to the upper back of each player using an adjustable neoprene harness. This GPS system uses signals from at least 3 Earth-orbiting satellites to determine the players' position at a given time and therefore allow the calculation of movement speeds and distance traveled (8,12). Despite a possible underestimation of high-intensity running distance with the time resolution of 1 Hz, good accuracy (r = 0.97) (2) and reliability (coefficient of variation = 1.7% [2] and 2.3% [3]) have been reported for the assessment of peak sprinting speed for this GPS device compared to a infrared timing system. Moreover, in the absence of a “gold standard” method, the current system has been reported to be capable of measuring individual movement patterns in other team sports (16).

Back to Top | Article Outline

Match Running Demands Analysis

Time-motion data of all the players who participated in the entire first and second halves were retained (n = 17 files from 7 different players). After collection, all match data were analyzed with the software provided by the manufacturer (Team AMS; GPSports, V1.2) designed to provide objective measures of physical match performance. Players' activities were coded into the following categories and speed thresholds: standing and walking (0–6.0 km·h−1), jogging (6.1–12.0 km·h−1), cruising (12.1–14.0 km·h−1), striding (14.1–18.0 km·h−1), high-intensity running (18.1–20.0 km·h−1), and sprinting (>20.1 km·h−1). The speed thresholds for each category were the same to those reported previously by Cunniffe et al. (4) using the GPS technology. Similar to Cunniffe et al. (4), the above categories were divided into further locomotor categories to provide an estimation of player work-to-rest ratios: (a) low-intensity activity (0–6.0 km·h−1) and (b) moderate-and-high-intensity activity (>6.1 km·h−1). The frequency of high-speed zone entries (sprints >20 km·h−1) and the highest speed recorded during the game were also collected. Average speed (kilometers per hour) was also calculated from the total distance covered in each half divided by the time spent on the ground for each individual player.

Back to Top | Article Outline

Exercise Intensity

Match exercise intensity was quantified by monitoring the HR during each match. The HR was continuously measured (every 1 second) with short-range telemetry (SPI Elite, GPSports) and was expressed in relation to the individual HRmax reached during the incremental treadmill test. In those players in whom HRs were higher in the course of the match than the determined value during the incremental treadmill test, the HRmax values obtained during the game were retained and used in the analysis. The HR data were classified based on percentage of total playing time spend in each of the following 6 HR zones: zone 1 (<60% HRmax), zone 2 (61–70% HRmax), zone 3 (71–80% HRmax), zone 4 (81–90% HRmax), zone 5 (91–95% HRmax), and zone 6 (>96% HRmax).

Back to Top | Article Outline

Statistical Analyses

Data are presented as mean ± SD. Differences between the first and second halves were determined using Student's dependent t-test. Differences between distance covered at different running intensities and time spent at different HR intensities were analyzed using a 1-way analysis of variance with repeated measures. When a main effect was found, Bonferroni's adjusted post hoc tests were applied. All analyses were carried out with SPSS 17.0 (SPSS Inc, Chicago, IL, USA) software with the level of significance set at p ≤ 0.05.

Back to Top | Article Outline

Results

Match Running Demands

Mean total distance (±SD) covered over the whole match by all the players was 1,580.8 ± 146.3 m, ranging from 1,348.8–1,975.7 m. Figure 1 shows the match running profile during each half. There were no significant differences in match running performance between the 2 halves. The players spent longer standing, walking and jogging (i.e., running speeds between 0 and 12 km·h−1) than at any other running speed (p < 0.05). Low-intensity activities represented 61% of total time, which consisted of 34.8% (549.7 ± 79.1 m) standing and walking and 26.2% (414.8 ± 105.1 m) jogging. Cruising, striding, high-intensity running, and sprinting represented 9.8% (154.6 ± 53.5 m), 15.5% (244.5 ± 80.1 m), 5% (79.5 ± 37.2 m), and 8.7% (137.7 ± 84.9 m) of total time, respectively. The player's work-to-rest ratio was 1:0.5 (i.e., for every 1 minute of work, there was 0.5 minutes of rest). The average speed obtained throughout the game was 6.4 ± 0.6 km·h−1, with no significant differences between the first and second halves (6.4 ± 0.6 and 6.4 ± 0.6 km·h−1, respectively).

Figure 1

Figure 1

Table 1 displays sprinting performance results obtained during matches. Maximum speed obtained by a player during a match corresponded to 29.9 km·h1, and the longer sprint record (>20 km·h−1) was of 67.1 m.

Table 1

Table 1

Back to Top | Article Outline

Exercise Intensity

The average HR in the first and second halves was 169 ± 4 (86.6 ± 2.0% HRmax) and 173 ± 6 (88.6 ± 3.0% HRmax), respectively, with no significant differences observed. Maximal HR was 193 ± 5 (98.9 ± 2.0% HRmax) in the first half and 194 ± 5 (99.3 ± 2.0% HRmax) in the second half with no differences observed. Figure 2 shows the percentage of playing time spent in each exercise intensity zone expressed as percentage of HRmax. The players spent most of their playing time at HR intensities between 81 and 90% HRmax, with significant differences observed between halves in zone 5.

Figure 2

Figure 2

Back to Top | Article Outline

Discussion

The aim of this study was to analyze for the first time the match running demands and exercise intensity associated with high-level men rugby 7s using an objective method like GPS technology. The only peer-reviewed study on the activity profile of male rugby 7 during competitive matches used notational analysis based on qualitative data and objective running performance (e.g., distance covered) was not provided (17); therefore, comparison of our results is not possible. The results of this study show that, during a rugby 7s match, a man rugby player covers 1,580.8 ± 146.3 m at various speeds, resulting in an average running speed of 6.4 km·h−1. With the same technology used in this study (i.e., GPS), it was found that male rugby union (15-a side) players covered a total match distance of 6,953 m and exercised at an average running speed of approximately 4.2 km·h−1 (4). Male rugby league (13-a side) players covered a total match distance of 4,982 m (forwards) and 5,573 m (backs) in a whole game (13). Using different technologies (i.e., video analysis), previous studies have reported that elite, male rugby union players covered average distances ranging from 4,662 to 6,389 m (1,7,11,18). Extrapolating the men rugby 7s playing time to the 15-a side male rugby match duration (∼80 minutes) (4), the resulting figure is a game coverage of approximately 9,000 m. Thus, as expected, overall running demands appear to be much higher in rugby 7s than in the a-15 rugby code.

The players studied in the present investigation spent 13.7% of the time in high-intensity running activities (18–20 km·h−1) or sprint (>20.1 km·h−1), which was slightly higher than the 10.5% previously reported in male rugby union players (4), and the 6.5% reported in rugby league players (13) (4.7% forwards vs. 8.3% backs). The average number of sprints (>20.1 km·h−1) reported in this study was approximately 7 per match (Table 1). On average, these sprints corresponded to an average distance of approximately 18 m, which falls within the range to those previously reported in different rugby codes with male players (1,4–6). Present data also reveal that rugby 7s players are required to sprint over distances >40 m. This implies that specific sprint training should reflect these demands and both short (≤20 m) and longer sprints (40–50 m) have to be included in the speed training routines.

The work-to-rest ratio values reported in this study (1:0.5) are substantially lower than any of those previously reported in other rugby union codes (ranging from 1:4 to 1:2) (1,4,7,11,13,14). Although comparisons with previous studies are difficult because analysis systems and criteria to classify motion categories have differed across studies, the present results suggest that stoppages in play are shorter and less frequent in rugby 7s than in the 15-aside code (11). The substantially reduced time spent in low-running speed activities identified in this study, together with the similar scores observed in rugby 7s compared with the other rugby codes, suggests a quicker transition of the ball from attack to defense phases and vice versa. This supports the notion that rugby 7s is played at much faster running tempo than the other rugby codes.

Despite the intensified running activity observed in this study, the average percentage of the total playing time that players spent at HR intensities >90% HRmax (i.e., 37.8%) was lower than those previously reported in male, rugby union players; backs and forwards spent 41.4 and 51.1% of the total time at HR intensities >90% of HRmax, respectively (4). Thus, the elevated running demands in rugby 7s do not appear to be associated with an increased overall exercise intensity (i.e., exemplified via HR responses). It can be speculated that the higher number or frequency of other game-related, nonlocomotive activities such as pushing and pulling in rucks or scrums observed in the other rugby codes can account, at least partially, for these differences in HR responses. These nonlocomotive activities are registered as low-running speed activities despite the high-intense nature of those actions (4). Further studies that combine objective GPS data with qualitative analysis of time spent in nonrunning activities are required to elicit more specific demands of the rugby 7s game.

This study is the first to show that rugby 7s is characterized by relatively high running demands intercalated with short periods of recovery. This study also suggests that the physical demands of rugby 7s are quite different from those encountered in other rugby codes. Collectively, these finding provide important information for prescription of training aimed at developing physiological qualities specific to the demands of competitive men rugby 7s.

Back to Top | Article Outline

Practical Applications

The assessment of the external (i.e., running demands) and internal (i.e., HR responses) load imposed during the actual competition is the first step preceding the design of specific conditioning programs and physical fitness testing protocols in rugby 7s. The training regimes of strength and conditioning coaches need to meet the increased overall running demands, the augmented high-intensity running actions, and the reduced work-to-rest ratios observed in rugby 7s in comparison with other rugby codes. As such, the development of appropriate levels of intermittent aerobic fitness is recommended.

Back to Top | Article Outline

Acknowledgments

This study was partially supported by a grant from the Consejo Superior de Deportes, Spain.

Back to Top | Article Outline

References

1. Austin D, Gabbett T, Jenkins D. The physical demands of Super 14 rugby union. J Sci Med Sport 14: 259–263, 2011.
2. Barbero-Alvarez JC, Coutts A, Granda J, Barbero-Alvarez V, Castagna C. The validity and reliability of a global positioning satellite system device to assess speed and repeated sprint ability (RSA) in athletes. J Sci Med Sport 13: 232–235, 2010.
3. Coutts AJ, Duffield R. Validity and reliability of GPS devices for measuring movement demands of team sports. J Sci Med Sport, 13: 133–135, 2010.
4. Cunniffe B, Proctor W, Baker JS, Davies B. An evaluation of the physiological demands of elite rugby union using global positioning system tracking software. J Strength Cond Res 23: 1195–1203, 2009.
5. Deutsch MU, Kearney GA, Rehrer NJ. Time-motion analysis of professional rugby union players during match-play. J Sports Sci 25: 461–472, 2007.
6. Deutsch MU, Maw GJ, Jenkins D, Reaburn P. Heart rate, blood lactate and kinematic data of elite colts (under-19) rugby union players during competition. J Sports Sci 16: 561–570, 1998.
7. Duthie G, Pyne D, Hooper S. Time motion analysis of 2001 and 2002 super 12 rugby. J Sports Sci 23: 523–530, 2005.
8. Edgecomb SJ, Norton KI. Comparison of global positioning and computer-based tracking systems for measuring player movement distance during Australian football. J Sci Med Sport 9: 25–32, 2006.
9. Engebretsen L, Steffen K. Rugby in Rio in 2016! Br J Sports Med 44: 157, 2010.
10. Gabbett T, King T, Jenkins D. Applied physiology of rugby league. Sports Med 38: 119–138, 2008.
11. King T, Jenkins D, Gabbett T. A time-motion analysis of professional rugby league match-play. J Sports Sci 27: 213–219, 2009.
12. Larsson P. Global positioning system and sport-specific testing. Sports Med 33: 1093–1101, 2003.
13. McLellan CP, Lovell DI, Gass GC. Performance analysis of elite Rugby League match play using global positioning systems. J Strength Cond Res, 25: 1703–1710, 2011.
14. Meir R, Newton R, Curtis E, Fardell M, Butler B. Physical fitness qualities of professional rugby league football players: determination of positional differences. J Strength Cond Res 15: 450–458, 2001.
15. Nicholas CW. Anthropometric and physiological characteristics of rugby union football players. Sports Med 23: 375–396, 1997.
16. Randers MB, Mujika I, Hewitt A, Santisteban J, Bischoff R, Solano R, Zubillaga A, Peltola E, Krustrup P, Mohr M. Application of four different football match analysis systems: A comparative study. J Sports Sci 28: 171–182, 2010.
17. Rienzi E, Reilly T, Malkin C. Investigation of anthropometric and work-rate profiles of Rugby Sevens players. J Sports Med Phys Fitness 39: 160–164, 1999.
18. Roberts SP, Trewartha G, Higgitt RJ, El-Abd J, Stokes KA. The physical demands of elite English rugby union. J Sports Sci 26: 825–833, 2008.
Keywords:

GPS technology; match-play demands; football; team sports

Copyright © 2012 by the National Strength & Conditioning Association.