Journal of Exercise Physiologyonline (JEPonline)

Rowing Performance 43 Journal of Exercise Physiologyonline (JEPonline) Volume 10 Number 4 June 2007 Managing Editor Tommy Boone, Ph.D. Editor-in-Chief Jon Linderman, Ph.D. Review Board Todd Astorino, Ph.D. Julien Baker, Ph.D. Tommy Boone, Ph.D. Lance Dalleck, Ph.D. Dan Drury, DPE. Hermann Engels, Ph.D. Eric Goulet, Ph.D. Robert Gotshall, Ph.D. Len Kravitz, Ph.D. James Laskin, Ph.D. Jon Linderman, Ph.D. M. Knight-Maloney, Ph.D. Derek Marks, Ph.D. Cristine Mermier, Ph.D. Daryl Parker, Ph.D. Robert Robergs, Ph.D. Brent Ruby, Ph.D. Jason Siegler, Ph.D. Greg Tardie, Ph.D. Lesley White, Ph.D. Chantal Vella, Ph.D. Thomas Walker, Ph.D. Ben Zhou, Ph.D. Official Research Journal of The American Society of Exercise Physiologists (ASEP) ISSN 1097-9751 Fitness and Training STRENGTH AND POWER DETERMINANTS OF ROWING PERFORMANCE CHUN-JUNG HUANG, THOMAS W. NESSER, JEFFREY E. EDWARDS. Exercise Physiology Laboratory, Department of Physical Education, Indiana State University, Terre Haute, USA ABSTRACT Chun-Jung Huang CJ, Nesser TW, Edwards JE. Physiological determinates of rowing performance. JEPonline 2007:10(4):43-50. Rowing is an activity that involves both the upper and lower body, making it a total body exercise. The purpose of this study was to determine which physiological variables account for the most variation in 2000m rowing performance. Ten male (age = 17.4 ± 0.7 yr, weight = 75.2 ± 11.2 kg, height = 181.4 ± 6.1 cm) and seven female rowers (age = 17.3 ± 0.6 yr, weight = 72.4 ± 14.9 kg, and height = 168.3 ± 6.7 cm) participated in this study. Performance variables tested include a 2000m rowing ergometer time trial (8.01 ± 0.69 min), vertical jump (42.6 ± 10.7 cm), inverted row (9.8 ± 6.3 rep), leg press (144.7 ± 25.4 kg), and back extension (26.3 ± 11.1 rep). Significant correlations (p 0.05) with 2000m rowing performance were identified for vertical jump (r = -0.736), inverted row (r = -0.624), leg press (r = -0.536), and height (r = -0.837). A stepwise multiple regression analysis identified height and leg press as the strongest predictors of 2000m rowing performance (R 2 = 0.807, p 0.05). With height removed as an independent variable, a stepwise multiple regression was run again, identifying vertical jump, weight, and age as the best predictors of 2000m rowing performance (R 2 = 0.842, p 0.05). Height and leg press were identified as the strongest predictors of 2000m rowing performance. With height removed as an independent variable vertical jump, weight, and age best predicted 2000m rowing performance. Inverted row, despite its strong correlation, did not further contribute to either prediction equation. The results of this study support the importance of strength and anaerobic power development in male and female club level rowers. Key Words: Athlete, Endurance, Training,

Rowing Performance 44 INTRODUCTION Rowing is a continuous movement that requires the production of both aerobic and anaerobic power. In the drive phase of the rowing cycle, rowers sequentially push with their legs then pull with their arms and lower back (1,2) requiring both muscular strength and endurance. Previous research has classified elite and club junior rowers through measurement of upper body strength (3), and attempted to predict rowing performance via anthropometric variables (4), upper body power (5), and quadriceps strength (6). However, it remains unclear whether strength and/or muscle endurance are factors in rowing performance since none of the mentioned studies considered reviewing both strength and endurance at the same time. METHODS Subjects Ten male and seven female club level rowers (15-18 yr) volunteered for participation in this study. Physical characteristics can be found in Table 1, 2, and 3. Procedures The participants completed a medical history questionnaire and signed an informed consent form prior to data collection. All experimental procedures were approved by university Institutional Review Board. The participants performed five tests on two separate days. The interval between each testing day was at least three days. They were asked to avoid strenuous physical activity 24 hours prior to testing. All tests were completed within two weeks. On day 1, the participants completed a counter movement vertical jump on a Vertec vertical height measuring device (MF Athletic Corp, Cranston, RI) to measure lower body power and a 2000-m rowing ergometer test on a Concept II rowing ergometer (Model C, Concept II, Morrisville, VT) to measure rowing performance. Participants were required to warm up for 500m at the stroke rate of 18-20 strokes min -1 on a rowing ergometer. On day 2, the participants first performed a maximum number of inverted rows on a squat rack (MF Athletic Corp., Cranston, RI) with a standard barbell to measure upper body muscle endurance, then a 1-repetition maximum (1 RM) leg press (Cybex International Corp., Medway, MA) to measure lower body strength, and finally a maximum number of back extensions (PFW-560 Roman Bench, Paramount Corp., Los Angles, CA) to measure lower back muscle endurance. Participants were required to warm up by jogging for five minutes. All tests were performed at the St. Vincent Sports Medicine Center in Indianapolis. The counter movement vertical jump was used to measure lower body power. Participants faced the Vertec with both feet flat on the floor, and reached as high as possible with either hand to determine reach height. Then, they jumped vertically as high as possible with one arm swing but no step, and touched a vane at the highest point of the jump. Reach height was subtracted from jump height to determine vertical jump height. Each participant completed three trials, while the best performance was used for data analysis. The 2000-m rowing ergometer test was a timed test to measure muscle endurance. Participants were asked to complete the 2000 meter distance in as short a time as possible. Participants worked at a setting of 1 on a Concept II ergometer. The final time was recorded.

Rowing Performance 45 For the inverted rows, participants lied in a supine position under a bar on a squat rack. The bar was set at a height of 3 feet. Their feet were placed on a bench approximately 24 inches high. The beginning position consisted of the arms fully extended with a pronated grip on the bar. Subjects pulled themselves up until their chest touched the bar. A new repetition began as soon as the participant reached the bottom position. Subjects maintained a rigid, supine position throughout the test (6). If a participant held the bottom position for more than 2 seconds or failed to maintain a rigid position, the test was terminated. The maximum number of inverted rows was recorded and used for data analysis. Next, the leg press was used to evaluate lower body strength. Participants grasped the seat s handle, and their back needed to be kept straight. Also, participants placed their feet on the machine rests, and they were required to flex the knee to 90 degrees. Individuals were allowed to warm-up with a light weight for 5 repetitions. Following a one minute rest period, a weight was estimated to allow 3 repetitions. Weights were increased as necessary (30 ~ 40 pounds) until a 1-repetition maximum (1 RM) had been determined. Three minute rest periods followed each set. If the participant failed, the load was decreased 15 ~ 20 pounds for the next attempt. By increasing or decreasing the load, the participants were able to complete a 1 RM within five sets. The maximum load was used for data analysis. Finally, the back extension was completed with the subjects in a prone position on a back extension bench, and their hips aligned with the front edge of the pad. They flexed their torso forward to a 90 degree angle at the hip, and then raised the trunk until their torso is parallel to the floor (7). Hands were kept clasped behind their head. A new repetition began as soon as the participant reached the bottom position. If a participant kept the bottom position for more than 2 seconds or failed to reach parallel, the test was terminated. The maximum number of back extension was recorded and used for data analysis. Statistical Analyses The dependent variable was the 2000-m time trial, and the independent variables were vertical jump, leg press, back extension, and inverted rows. A stepwise multiple regression analysis was used to determine predictors of 2000-m rowing time. Pearson correlation coefficient (r) was used to establish a relationship between 2000-m rowing performance and the independent variables. Statistical significance was set at P 0.05. RESULTS Physiological and performance variables are presented in Tables 1 and 2. Pearson correlation coefficient (r) was used to compute the correlation between 2000-m rowing performance and age, height, weight, experience, vertical jump, inverted row, leg press, and back extension (Table 4). Significant correlations (P 0.05) were identified between 2000-m rowing performance and height (r = -0.837), vertical jump (r = -0.736), inverted row (r = -0.624), and leg press (r = -0.536). There were no significant correlations for age, weight, experience, or back extension. Stepwise multiple regression analysis identified height and leg press as the two variables to best predict 2000-m rowing performance. Since height cannot be trained it was removed as a performance predictor. When height was removed as an independent variable, vertical jump, weight, and age were identified as the best predictors of 2000-m rowing performance. Results are shown in Table 5.

Rowing Performance 46 Table 1. Male Physiological and Performance Variables (n = 10) Variables Mean Minimal Maximal Age (years) 17.4±0.7 15.8 18.3 Height (cm) 181.4±6.1 172.7 193 Weight (kg) 75.2±11.2 64.4 99.8 Experience 23.2±11.2 6 36 (months) Vertical Jump 49.5±7.1 36.8 63.5 (cm) Inverted Row 13.9±4.0 8 20 Leg Press (kg) 154.6±26.9 95.5 186.4 Back Extension 29.5±13.5 13 57 DISCUSSION The purpose of this study was to examine male and female rowers on a number of physiological variables to predict which may account for variation in 2000-m rowing performance. A stepwise multiple regression identified height as the strongest predictor of 2000-m rowing performance (P 0.05 and R 2 = 0.70 ). 2000-m Time (s) 452.2±25.3 416 494 This supports the importance of height for success in rowing performance as suggested by Shephard and Astrand (4) who stated that endurance is affected by body dimension. They demonstrated that when standing height increases so does muscle leverage and body mass. As height increases so does sitting height (trunk length), which is significantly related to rowing performance. Table 2. Female Physiological and Performance Variables (N = 7) Variables Mean Minimal Maximal Age (years) 17.3±0.6 16.7 18.1 Height (cm) 168.3±6.7 160.0 180.3 Weight (kg) 72.4±14.9 61.2 99.8 Experience (months) 28.4±8.9 13 37 Vertical Jump (cm) 32.6±6.0 25.4 43.2 Inverted Row 3.9±3.4 0 9 Leg Press (kg) 130.5±15.3 113.6 159.1 Back Extension 21.7±3.6 16 27 2000-m Time (s) 521.4±19.2 486.0 551 Additionally, Hirata (8) mentioned gold medal winners were consistently taller than national champions in the single sculls and Bourgolis et al. (9) found that during the 1997 International World Junior Rowing Championships, finalists were taller than nonfinalists. Other researchers have stated that body height correlates well with 2000-m rowing performance (10, 11), as taller rowers have the advantage of producing greater rowing performance (12), since their greater height allows a longer stroke. The second variable identified as a predictor of 2000-m rowing performance was leg press. Leg press was used to evaluate the lower body strength due to its similarity to the rowing leg drive. Jensen et al. (13) found that leg extension strength was correlated with 2000-m rowing power. Hagerman (6) has also shown a correlation between quadriceps strength and rowing performance due to the power provided during the leg drive in the rowing stroke. These studies support the result that leg strength is vital to rowing performance.

Rowing Performance 47 Table 3. Combined Physiological and Performance Variables (N = 17) Variables Mean Minimal Maximal Age (years) 17.4±0.6 15.8 18.3 Height (cm) 176.0±9.0 160.0 193.0 Weight (kg) 74.0±12.5 61.2 99.8 Experience (months) 25.4±10.3 6 37 Vertical Jump (cm) 42.6±10.7 25.4 63.5 Inverted Row 9.8±6.3 0 20 Leg Press (kg) 144.7±25.4 95.5 186.4 Back Extension 26.3±11.1 13 57 2000-m Time (s) 480.7±41.6 416.0 551 To examine other independent variables, height was removed as a possible predictor to 2000-m rowing performance. This second analysis identified vertical jump, weight, and age as additional predictors of 2000-m rowing performance. Table 4. Pearson Correlation Coefficients Between 2000-m Rowing Performance and Physical and Physiological Variables (N = 17) *P 0.05 Variables r Age -0.407 Height -0.837* Weight -0.471 Experience 0.091 Vertical Jump -0.736* Inverted Row -0.624* Leg Press -0.536* Back Extension -0.210 Vertical jump was used to measure lower body power. Yoshiga and Higuchi (10) examined 332 young rowers (age 21±2 yrs) in bilateral leg extension power on a 2000-m rowing ergometer. They emphasized that rowing involved the most muscles in the body, and the bilateral leg extension power is very important during rowing performance. Gayer (14) demonstrated that peak power was one of the physiological characteristics that provided the best way to differentiate between successful and unsuccessful rowers. Furthermore, in a study of female rowers, 75.7 % of the variation in 2000-m indoor rowing performance time was predicted by mean power during a rowing Wingate test (5). This information deems it necessary to emphasize the development of peak power in the training of rowers.

Rowing Performance 48 Table 5. Regression Equations Predicting 2000-m rowing Performance (N = 17) Variables R 2 R 2 X 100 SEE Height 0.700 49 23.53 Leg Press 0.807 65.1 19.53 Y = 1168.769 3.452 (X 1 ) 0.556(X 2 ) Y = 2000-m row time X 1 = height (cm) X 2 = leg press (kg) Variables R 2 R 2 X 100 SEE Vertical Jump 0.541 29.3 29.11 Weight 0.775 60 21.10 Age 0.842 70.9 18.33 Y = 1009.321 2.865 (X 1 ) 1.328 (X 2 ) 17.739 (X 3 ) Y = 2000-m row time X 1 = Vertical Jump (cm) X 2 = Weight (kg) X 3 = age (years) The second variable in the second regression equation identified as a predictor of 2000-m rowing performance was weight. Russell et al. (15) stated that body mass was correlated with 2000-m performance time (r = -0.41) and was also a predictor of 2000-m rowing performance. Many studies have shown that typically open class rowers are tall, lean and have a high percentage of lean body mass (particularly slow twitch muscle fibers (6, 16, 12, 17). Even though there was no significant correlation between weight and 2000-m rowing performance (r = -0.471) in the current study, weight improved the prediction of 2000-m rowing performance by 23.4%. The third variable identified in the second regression as a predictor of 2000-m rowing performance was age. Few studies reviewed for the present research identified a relationship between age and rowing performance. Seiler at al. (18) examined 2487 male rowers (age 24 to 93 yrs) and 1615 females rowers (age 24 to 84 yrs), and found that there was a moderate correlation between age and rowing performance (r=-0.58 for males and r = 0.46 for females). Since age is related to many anthropometric characteristics, it is very much dependent on the population of rowers as being a predictor of rowing performance.

Rowing Performance 49 The inverted row was used to measure strength in the upper back. Even though the inverted row was not a predictor of rowing performance, it did have a significant negative correlation with 2000-m rowing performance (r = -0.624) suggesting upper back strength may very well contribute to 2000-m rowing performance. CONCLUSIONS The results of this study identified height and 1RM leg press as the best predictors of 2000-m rowing performance. The identification of height and leg strength indicates the importance of leg and trunk length that could extend the driving phase. This could be used to identify success in potential rowers though it is not a factor that can be trained. Leg strength can be trained and improved in rowers with an expectancy of increasing rowing performance. Which type of training is necessary to improve leg strength and ultimately rowing performance is up to the individual coach and/or athlete. It is important to note a limitation to this study is subject size. Due to the low number of subjects, genders had to be combined for statistical analysis. Had numbers been higher, analysis would have been completed for each gender thus the results may have been different. Address for correspondence: Nesser, TW, PhD., Department of Physical Education, Indiana State University, Terre Haute, IN, USA, 47885. Phone (812)237-2901; FAX: (812)237-4338; Email. tnesser@indstate.edu. REFERENCES 1. Dawson R, Lockwood R, Wilson J, Freeman G. The rowing cycle: Sources of variance and invariance in ergometer and on-the-water performance. J. Motor Behav. 1998; 30(1): 34-43. 2. Smith R, Loschner C. Biomechanics feedback for rowing. J. Sports Sci. 2002; 20(10):783-791. 3. Sharp N, Koutedakis Y. A modified Wingate test for measuring anaerobic work of the upper body in junior rowers. Brit. J. Sport Med. 1986; 20(4):153-156. 4. Shephard R, Astrand P. Endurance in Sport. Champaign, Illinois: Human Kinetics. 1992. 5. Riechman S, Zoeller R, Balasekaran G, Goss F, Robertson R. Prediction of 2000 m indoor rowing performance using a 30 s sprint and maximal oxygen uptake. J. Sports Sci. 2002; 20(9):681-687. 6. Hagerman F. Applied physiology of rowing. Sports Med. 1984; 1(4):303-326. 7. Pierce K. Back extension & snatch pull. J of Strength Cond. 1998; 20(1):32. 8. Hirata, K. Selection of Olympic Champions. Tokyo: Hirata Institute.1979. 9. Bourgois J, Claessens A, Janssens M, Renterghem B, Loos R, Thomis M, Philippaerts R, Lefevre J, Vrijens J. Anthropometric characteristics of elite female junior rowers. J. Sports Sci. 2001; 19(3):195-202. 10. Yoshiga C, Higuchi M. Bilateral leg extension power and fat-free mass in young oarmen. J. Sports Sci. 2003; 21(11):905-909. 11. Yoshiga C, Higuchi M. Rowing performance of female and male rowers. Scan. J. Med. Sci. Sports. 2003; 13(5):317-321. 12. Shephard R. Science and medicine of rowing: A review. J. Sports Sci. 1998; 16(7):603-620. 13. Jensen R, Freedson P, Hamill J. The prediction of power and efficiency during near-maximal rowing. Euro. J. Appl. Phys. Occup. Phys. 1996; 73(1/2):98-104. 14. Gayer C. Physiological discriminators of rowing performance in male, club rowers. Unpublished Master s Thesis, Washington State University. 1994. 15. Russell A, Le Rossignol P, Sparrow W. Prediction of elite schoolboy 2000-m rowing ergometer performance from metabolic, anthropometric and strength variables. J. Sports Sci. 1998; 16(8):749-754..

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