ABSTRACT
The purpose of this study was to determine if swimming skill could be interpreted directly from the energy cost of swimming (Cs) per unit distance at a given velocity. A total of 101 males were studied. Three performance levels were determined from the slower (A) to the faster (B, C) times over a 400 m swim. For a given velocity, there were no statistical differences in Cs between the three levels. However, at level C and at 1.1 m/s, Cs was reduced by 55% and 25% when compared to levels A and B and when calculated per unit of surface area and hydrostatic lift. To evaluate the specific influence of arm length two groups of long- and short-armed swimmers were selected among swimmers of similar height and performance. The Cs was significantly (P<0.05) higher by 12±3.3% for short-armed than long-armed swimmers. To evaluate the influence of different types of swimming technique two other groups of similar performance and anthropometric characteristics were selected. The Cs was significantly higher by 15+3.8% for swimmers preferentially using their legs than their arm (P<0.05). The Cs of the sprinters was 16.5 ± 3% higher than that of the long-distance swimmers. For all the groups, Cs increased with velocity on average by 10% every 0.1 m/s. Thus, technical ability cannot be interpreted directly from Cs. Perfor-mance levels, body size, type of swimming technique and velocity must also be taken into account.
