Correlates of Performance at the USRowing Youth National Championships: A Case Study of 152 Junior Rowers

Submitted by Alex Wolff & Pavle Mikulic

ABSTRACT
This study was designed to assess the extent of the relationship between a number of variables (2000 m rowing ergometer score, weight adjusted 2000 m rowing ergometer score, height, weight, and years of experience) and placement at the USRowing Youth National Championships, in order to highlight areas for college recruiters and aspiring junior rowers to focus on. Data for 152 athletes competing in 18 events was collected. Data collection was accomplished through a site search of “berecruited.com” for the keywords “youth nationals” “nationals” and “rowing”; athletes reported placement was then verified against the official race results. Athletes were subdivided into categories based on boat size, event type, weight class, and gender. In almost all categories (with the exception of men’s open weight sweep and lightweight sculls) a significant (p<0.05) correlation between rowing ergometer score and placement was established. The highest correlation between rowing ergometer score and placement was observed in women’s lightweight sculls (r=0.76). Weight adjustment provided notable improvements in only two categories over unadjusted ergometer score: men’s open weight sculls (r=0.79 vs. r=0.72) and men’s lightweight sculls (r=0.49 vs. r=0.42). Weight independent of ergometer score and experience did not correlate with final rankings. Height independent of ergometer score correlated with final rankings in only one category - men’s open sculls (r=0.38). While it is possible that the small sample sizes in some categories may have impacted the results, a clear trend emerges emphasizing the importance of unadjusted rowing ergometer score over other factors in evaluating junior rowers at the national level.

INTRODUCTION
Rowing is a strength-endurance activity that requires both aerobic and anaerobic capability for successful performance (Maestu, Jurimae, & Jurimae, 2005; Secher, 2000). A typical rowing race takes place over a 2000 m course and, depending on the boat category and weather conditions, is characterized by 5.5 – 7.5 minutes of exhaustive physical effort. Rowing comprises two distinct, but closely related disciplines: sculling and sweep rowing. The main distinction between the two is that sculling involves the use of two oars per rower, one in each hand, versus only one slightly larger oar for sweep rowers. Of the two, sculling is considered more technically demanding, and sweep is more popular, particularly at the collegiate level where major sculling regattas are largely nonexistent. All rowing boats can also be divided into two additional categories: small boats (boats with one or two crew members, i.e. single sculls, double sculls and pairs) and large boats (boats with four or eight rowers, i.e. quadruple sculls, coxed and coxless fours and eights). Typically, the larger the boat is, the more stable it becomes because of the additional hull width and length. Because of this, a single can be a much different boat to row than an eight. Additionally, larger boats increase the importance of synchronization of crew members’ strokes to achieve increased speed (Baudouin & Hawkins, 2002). A more recent addition to the world of competitive rowing has been the advent of lightweight events. USRowing defines lightweight junior rowers as weighing no more than 160 or 130 pounds for men and women, respectively. Lightweight events at Youth National Championships are lightweight double, lightweight four, and lightweight eight.

Besides its international popularity as a competitive sport and its continuous presence on Olympic Games from the very first modern Olympic Games held in 1896 in Athens, Greece, rowing is also a major collegiate sport in various countries, including the United States. With this in mind, it may be of particular interest for college recruiters to gain a better understanding of the factors that contribute to rowing performance in junior rowers competing at the most important event at the national level: the USRowing Youth National Championships. Likewise, it may be important for prospective junior rowers and their coaches to be able to focus on those factors which contribute to greater on-water performance.

College recruiters are continuously striving to improve the selection process for their rowing teams and, when assessing a junior rower’s ability, they can be presented with a wide array of factors to consider. With this in mind, we designed this study to assess the strength of association between a number of objective variables and race placement at the USRowing Youth National Championships. The variables we examined include years of experience, body height, body weight, 2000 m rowing ergometer score and 2000 m weight adjusted rowing ergometer score. Based on our two earlier studies (Mikulic et al. 2009a,b) in which we observed a strong correlation between 2000 m rowing ergometer performance scores and final rankings at both World Rowing Championships and World Junior Rowing Championships, we hypothesized that 2000 m rowing ergometer score (an “all-out” effort over a distance of 2000 m) would be the strongest correlate to placement at the USRowing Youth National Championships. However, the extent to which this is true and the relation of other variables to rowing performance in junior rowers competing at the USRowing Youth National Championships has yet to be determined.

METHODS
The data for this study was collected by performing a site search of athlete’s profiles on the “berecruited.com” web site. This site allows athletes to upload their information such as personal best 2000 m ergometer score along with other facts such as their height, weight, and notable race results, all in an effort to increase their visibility to college recruiters. We performed the search using the keywords “youth nationals” “nationals” and “rowing”. Those profiles which listed a 2012 or 2013 Youth Nationals result were then matched to the official race results from their respective year to verify that athletes reported placement. Once verified, that athlete’s information and placement was included in the data set. The variables recorded were: 2000 m rowing ergometer score (personal best), height, weight, years of experience, and weight adjusted 2000 m ergometer score based on the following formula (6):

Adjusted ergometer score = (rower weight/270)^0.22* ergometer score in seconds

The data was then divided into a number of sub categories which were as follows: open weight overall, open category scull and open category sweep. Rowers were further classified as open category men, open category women, lightweight men, and lightweight women. The correlation between each factor and placement was established for each category using the Pearson product moment correlation coefficient. The significance of correlation coefficients was tested to a confidence of p=0.05. In addition, we performed a series of independent samples t-tests to examine the differences in rowing ergometer scores between selected groups of rowers.

RESULTS
Tables 1 and 2 indicate that 2000 m ergometer scores, both in absolute values and adjusted to a rower’s weight, demonstrate the most consistent association with final rankings at the USRowing Youth Championships. This is especially evident in women’s events in which the correlations between the ergometer scores and final rankings were evident in all of the observed categories (i.e. scull and sweep, open category and lightweight rowers).

Table 1. Correlation coefficients between final rankings at the USRowing Youth Championships and five observed variables in groups of male junior rowers
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Table 2. Correlation coefficients between final rankings at the USRowing Youth Championships and five observed variables in groups of female junior rowers
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T-tests were utilized to test for differences in ergometer scores between sweep oar rowers and scullers (Table 3). The only category in which a significant difference was observed between scullers and sweep oar rowers was the men’s lightweight category. There was no significant difference between women’s lightweight sweep oar rowers and scullers, women’s open category sweep oar rowers and scullers, or men’s open category sweep oar rowers and scullers. Similarly, when ergometer scores of big vs. small boat rowers were compared, no significant differences were observed across the categories except for the men’s lightweight category (Table 4).

Table 3. 2000-m Rowing ergometer scores (in seconds) for various categories of rowers and independent samples t-test results for differences between sweep oar rowers vs. scullers
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Table 4. 2000 m Rowing ergometer scores (in seconds) for various categories of rowers and independent samples t-test results for differences between rowers in small vs. big boats
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DISCUSSION
In this study we aimed to identify the variables that showed the strongest association with the final rankings at the most important competition for junior rowers in the US – the USRowing Youth Championships. The results (Tables 1 and 2) indicate that 2000 m rowing ergometer scores, both in absolute values and adjusted to body weight, displayed the strongest correlations across categories, both for junior men and women. In junior men, the strongest correlations were observed for open category sculling events (r=0.72 for ergometer score; r=0.79 for weight adjusted ergometer score) while in junior women the strongest correlation were observed for lightweight category sculling events (r=0.76 for both ergometer score and weight adjusted ergometer score). These findings largely corroborate findings from our earlier study (Mikulic et al. 2009a) in which we observed moderate to high correlation coefficients between 2000 m rowing ergometer score and final rankings at the World Rowing Junior Championships. In that study, rowing ergometer scores of junior rowers correlated with their final rankings in all 13 events in which the junior rowers competed at the 2007 World Rowing Junior Championships with the correlation coefficient ranging from r=0.31 to r=0.92.

Weight adjusted rowing ergometer scores are ergometer scores normalized to that specific rowers speed in an eight boat. Since heavier rowers sink the boat further into the water, thus creating more wetted surface and drag, they must be capable of producing greater power to achieve the same speed as a lighter rower. This should, in theory, improve upon the correlation produced by non-weight-adjusted scores which we failed to observe on a consistent basis in the present study (Tables 1 and 2). The categories for which weight adjustment provided the largest improvement (men’s open and lightweight sculls) had comparatively small standard deviations versus other groups. It is possible that weight adjustment thus becomes more of a factor since the difference in “raw power” (represented by the ergometer score) between rowers was not as exaggerated as other categories for which weight adjustment provided no improvement.

Experience, height and weight of junior rowers did not generally correlate with final rankings at the USRowing Youth Championships, with the exception of height which correlated with the final rankings in junior men’s open category sculling events (r=-0.38), and experience which correlated with final rankings in junior women’s open category sculling events (r=-0.52). This general lack of association between the body size variables (i.e. height and weight) and final rankings at the Championships is somewhat surprising given the well documented importance of body size for rowing performance (for a review, see Shephard, 1998) including rowing performance at the junior level (Burgois 2000; 2001). It is possible that since Youth Nationals is a lower level of competition than junior worlds, the regatta analyzed in the studies cited, the larger variance in skill and general fitness (and, by extension, the ergometer score) would outweigh the importance of body size.

There appear to be no differences in 2000 m rowing ergometer scores of junior male and female rowers who compete in sculling vs. sweep rowing events (Table 3). The exception are junior men’s lightweight categories in which scullers are about 10 seconds faster than their counterparts from sweep rowing boats. Similarly, 2000 m rowing ergometer scores of junior men and women do not appear to differ for those competing in big vs. the small boats. Again, the only exception are junior lightweight categories in which rowers competing in a small boat are about 10 seconds faster than their counterparts competing in a big boat. Apparently, 2000 m ergometer score does not appear to be a factor for selecting a junior rower to a sculling vs. the sweep boat or the big vs. the small boat. In our earlier study (Mikulic et al., 2009a) we also observed no differences between 2000 m ergometer scores of scullers and sweep rowers competing at the 2007 World Junior Championship, either for male or female rowers (no rowers compete in lightweight categories at World Junior Championships). However, in that study, we also observed that better 2000 m ergometer performers tended to be selected to large boats. We must, however, mention a limitation of comparing 2000 m ergometer scores of various groups of junior rowers in this study as the numbers of rowers in comparing groups differed substantially thus reducing the accuracy of t-test analyses.

CONCLUSIONS
In conclusion, the most important factor to consider in the recruitment of junior rowers is rowing ergometer score over 2000 meters. This finding largely confirmed our original hypothesis. In certain categories (particularly men’s open weight categories), weight adjusting provided some improvements and may be useful in distinguishing between candidates with similar ergometer scores. Years of experience, height, and weight independent of ergometer score were shown to have very little correlation with actual boat speed.

APPLICATIONS IN SPORT
When evaluating junior rowers as potential candidates for recruitment, the most important factor appears to be the 2000 m rowing ergometer score. While weight adjustment can in certain scenarios aid in evaluation, it is only marginally effective at best. Experience, height, and weight should be largely ignored as these factors have very little impact on boat speed. Junior rowers looking to perform well at Youth National Championships should focus their efforts on improving their 2000 m rowing ergometer scores.

ACKNOWLEDGMENTS
None

REFERENCES
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4. Mikulic, P., Smoljanovic, T., Bojanic, I., Hannafin, J., Pedisic, Z. (2009a). Does 2000-m rowing ergometer performance time correlate with final rankings at the World Junior Rowing Championship? A case study of 398 elite junior rowers. Journal of Sports Sciences, 27(4), 361–366.

5. Mikulic, P., Smoljanovic, T., Bojanic, I., Hannafin, J.A., Matkovic, B.R. (2009b). Relationship between 2000-m rowing ergometer performance times and World Rowing Championships rankings in elite-standard rowers. Journal of Sports Sciences, 27(9), 907–913.

6. Weight Adjustment Calculator. (n.d.). Home. Retrieved November 23, 2013, from http://www.concept2.com/indoor-rowers/training/calculators/weight-adjustment-calculator

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9. Shephard, R.J. (1998). Science and medicine of rowing: a review. Journal of Sports Sciences, 16, 603-620.