Relationships between anthropometric parameters and motor tests in young rugby players

INTRODUCTION Anthropometric characteristics of rugby players are very important for their performance. Aim of this study is to investigate the relationships between anthropometric parameters and selected motor tests indicative of rugby performance. METHODS 70 young rugby players (15,3  0,52 yr; 183,9  4,3 cm 91,02  15,84 kg) participating to meetings of the Italian Rugby Federation were recruited. They were assessed with a battery of 6 motor tests (squat- and countermovement jump, 30m running speed, 35 m shuttle running test, sit and reach, shuttle endurance test) and 26 anthropometric measurements (height, weight, 7 linear trunk and limbs lengths, 8 girths, 2 bone diameters and 7 skinfolds). Pearsons’ r correlation coefficient, cluster and factor analysis were used to study the relationships between variables. RESULTS 6 clusters were obtained from the correlation matrix including motor tests and anthropometric variables. The first one includes weight, waist, some skinfolds and girths. Other trunk and limbs girths are covered by the second cluster. In the third one motor strength and speed motor tests are included. The fourth cluster covers the endurance test linked to thigh, triceps and sural skinfolds. The fifth includes height and upper limb linear measurements. Humerus and wrist diameters are connected with flexibility test in the sixth cluster. 12 variables among the most representative of each cluster were selected. From the factor solution with varimax rotation 3 factors were extracted. The first factor, accounting for 42% of total variability, includes mass measures (body weight, chest and arm girths, and 3 skinfolds) and femur diameter. Motor tests are weakly and negatively saturated with this factor. The second factor, accounting for 23% of total variability, covers especially strength and speed tests. Endurance test is weakly but positively saturated with this factor, while 3 skinfolds are negatively saturated with motor performance. The third factor accounts for 12% of total variability and includes above all height, femur diameter and, negatively correlated, endurance test and shuttle running test. CONCLUSIONS It is important in rugby players to monitor body mass parameters and skinfolds because they may have a negative influence on performance. Highest players have to train agility because they tend to have the worst performances in agility tests.