Methods

SAMPLE

Forty three countries participated in the male events of the 1997 World Junior Rowing Championships, and participants from 41 countries were measured. Anthropometric data were collected on 383 junior male rowers, who included competitors and reserves (4.4% of the total sample). Coxwains were not measured. With 430 participating male athletes, the sample represented 89% of the population. Most of the rowers were from Europe (83.8%) and most were white (91.6%). For all rowing events, 80–100% of the competitors were measured, including 83% of the winners and medallists as well as 89% of the finalists. The age of the junior rowers varied between 15.1 and 18.6 years with a mean of 17.8 (0.7) years. They trained 7 to 10 times (10–15 hours) a week.

DATA COLLECTION

The protocols and techniques for this project were approved by the board of the Fédération Internationale des Sociétés d'Aviron. When the rowers arrived, they completed a form requesting certain personal and training data. Techniques were based on the procedures given by Claessens et al.⁹ For some measurements, the procedures outlined by Lohman et al,¹⁰ Norton et al,¹¹ and Ross and Marfell-Jones¹² were followed. The selected anthropometric dimensions were based on (a) the factor analytical classification of physique to characterise the different components of body build,¹³ (b) the measurements as used in studies on male and female rowing athletes,^{4–7, 14, 15} and (c) the measurements used in the physical fitness surveys on Belgian boys¹⁶ for reference.

After each subject had been “landmarked”, they were directed to one of the five stations for measurement. Each anthropometrist took the same measurements and was assisted by a recorder. In addition to age, the following measures were obtained: body mass; stature; sitting height; acromial height; radial height; dactylion height; tibial height; leg length (stature minus sitting height); arm length (acromial height minus dactylion height); biacromial diameter; bicristal diameter; humerus and femur widths; biceps, upper arm, forearm, thigh, and calf girths; and biceps, triceps, subscapular, suprailiac, thigh, and calf skinfolds. All bilateral measurements were obtained from the left side of the body.⁸

DATA ANALYSIS

Variables were tested for their skewness. Except for the biceps skinfold, the suprailiac skinfold, and the calf skinfold, all other variables fitted to a normal distribution. Mean, standard deviation, and minimum and maximum values are presented.

As most of the subjects were European and white, normative reference data (for the age closest to the mean chronological age of the male junior rowers) of Belgian secondary schoolboys aged 17.5–18 years were used for comparison.¹⁶ A profile chart with norms, using percentiles (P values of 5, 10, 25, 50, 75, 90, 95), was constructed. To compare the anthropometric data of finalists and non-finalists, an independent two sample t test analysis was carried out. The 1% level was chosen to represent statistical significance. The statistical analysis system programme¹⁷ was used.

Results

Comparisons between male junior rowers and the normative reference group show that the rowers are heavier (+ 17.5 kg), taller (+ 12.0 cm), and have a greater sitting height (+ 5.4 cm) and longer legs (+ 6.7 cm) (table 1). Junior rowers also have higher values for biacromial diameter (+ 2.4 cm), humerus width (+ 0.6 cm), femur width (+ 0.7 cm), biceps girth (+ 4.8 cm), thigh girth (+ 6.6 cm), and calf girth (+ 2.8 cm). As compared with the reference group, male junior rowers also have higher values for the triceps (+ 1.1 mm) and subscapular (+ 0.6 mm) skinfolds, but a smaller suprailiac skinfold (− 1.1 mm).

Finalists are heavier and have higher values for length, breadth (except for the bicristal diameter), and girth dimensions than the non-finalists (table 2). No significant differences are recorded between finalists and non-finalists for skinfold thicknesses, except for the triceps skinfold.

Table 3 gives an anthropometric profile chart. The scores for 20 anthropometric dimensions are located on the chart together with the corresponding percentile values—for example, P5, P10, P25, P50, P75, P90, and P95.

Discussion

Rowing is a strength endurance type of sport, and body size and mass are undoubtedly performance related factors.^{2, 3, 18, 19} An anthropometric profile of young rowers was carried out using a standard test battery, which includes body mass, stature, length, and breadth variables for the estimation of skeletal robustness, arm and leg girths for the evaluation of muscle development, and skinfold thicknesses for the estimation of fat mass and fat-free mass.⁸ The individual data were compared with a reference group. A further step is the construction of a profile chart with norms. The American College of Sports Medicine²⁰ argues that youngsters should, if possible, be counselled towards sports that are realistic given the individual body type.

The male junior rowers were 7% taller and 27% heavier than the reference group.¹⁶ On the basis of the descriptive data for 14 male adult champions,²¹ Shephard² concluded that outstanding rowers are 10% taller and 27% heavier than the general Canadian population. Malina²² suggested that there is no effect of regular training for rowing on statural growth and noted that rowers are already taller than average during childhood, maintaining their position relative to reference data during childhood and adolescence.

Table 4 gives a comparison of the mean age, stature, and body mass of male junior^23–25 (J Bourgois and J Vrijens, personal communication) and senior^{6, 18, 19, 26, 27} rowers competing in international championships. The mean stature of elite junior rowers varies between 187 and 192 cm, which is similar to the adult heavyweight elite rower (185–192 cm). On the other hand, heavyweight rowers seem to be heavier (79–93 kg) than the elite junior rowers (81–84 kg). Weight classification is part of rowing in World Championships (since 1974) and in Olympic Games (since 1996) at the senior level, but not at the junior level. The physical characteristics of male elite lightweight rowers (maximal weight for a single rower less than 72.5 kg and an average for every boat, except the single scull, of 70.0 kg) differ from their heavier peers and junior rowers (table 4). Our group of junior rowers are on average 6.7 cm taller and 11.9 kg heavier than lightweight rowers.⁶

Junior rowers have greater length dimensions and greater breadths and girths than the reference group¹⁶ and lightweight rowers⁶ but lower values (except for the bicristal diameter) than heavyweight rowers²⁶ (table 5). Sklad et al²⁸ found that a year of training increased arm and chest circumferences, and relative body mass in 41 male junior rowers aged 17–18 years.

The most able young rowers could be distinguished by their stature, skeletal robustness, and muscular development.²⁹ This is supported when comparing the anthropometric characteristics of finalists and non-finalists. Finalists were heavier and taller, with higher values for length, breadth (except for the bicristal diameter), and girth dimensions (table 2). Data for adult heavyweight rowers indicate that winners are consistently heavier and taller than the average for competitors participating in World Championships and Olympic Games.^{19, 30} Rodriguez⁶ found that lightweight medallists are lighter (−0.6 kg) than non-medallists, with higher values for length, breadth, and girth dimensions.

Calculated from the mean values in the different studies,^{6, 16, 26} junior rowers seem to have a lower sitting height relative to stature (51.6%) and a higher leg length relative to stature (48.4%) compared with the normative reference group¹⁶ (52.1% and 47.9% respectively) and the heavyweight Olympic rowers²⁶ (52.1% and 47.9% respectively). No differences were found between junior rowers and elite lightweight rowers.⁶ Long legs increase the drive phase of the rowing stroke.

As compared with Olympic heavyweight rowers,²⁶ junior rowers have somewhat higher values for the subscapular, thigh, and calf skinfolds, but a lower value for the triceps skinfold (table 5). Considerably thinner skinfolds were found in elite lightweight rowers.⁶

To evaluate the physical characteristics of junior rowers, an anthropometric profile chart was constructed (table 3). This profile gives an overall evaluation of the body characteristics of a subject in relation to his group. The chart can be used as a screening device and the interpretation of any profile should therefore be seen in its specific individual context.

In conclusion, elite male junior rowers are tall and heavy, with greater length, breadth, and girth dimensions than a reference group of the same chronological age. Within the group of elite male junior rowers, significant differences exist between finalists and non-finalists in length, breadth, and girth dimensions and for body mass. The anthropometric profile chart is a useful instrument for coaching and advising. It allows sport scientists and coaches to construct anthropometric profiles easily for individual rowers against templates.