SPECIFICITY IN THE STRENGTH AND POWER PROFILES OF ELITE ATHLETES 1 Steph Forrester and 2 Matt Pain 1 STI, Loughborough University, UK; 2 SSES, Loughborough University, UK email: s.forrester@lboro.ac.uk; web: www.sports-technology.com. INTRODUCTION The strength and power requirements to optimize athletic performance are sport-specific. Previous studies comparing the strength and power characteristics of athletes from different sports have generally focused on single isolated movements, e.g. 1 RM squat, bench press, maximum jump height [1]. The subject-specific nature of the strength – speed relationship [2] indicates that care is required when extrapolating single measurements to more realistic conditions. Nevertheless, assessing how well adapted the strength – speed relationship of an athlete is to the specific demands of their sport may have implications in talent identification and athlete development. This study aimed to determine whether there are significant differences in the strength – speed and power – speed profiles of five elite athletes from different sports. This was based on measurements of maximum voluntary torque over a range of speeds for knee and hip, extension and flexion. A further aim was to qualitatively assess how well their profiles matched sport-specific demands. METHODS Five elite male athletes (Table 1) gave informed consent in accordance with the Loughborough University ethics board. Maximal effort contractions were conducted on a Cybex NORM dynamometer. Measurements were taken for extension and flexion of the knee and hip. For each joint action five isometric trials and eight eccentric- concentric trials covering the range of velocities 50° to 400° s -1 were performed using an existing protocol [3]. Maximum torque for each isometric trial and maximum isovelocity torque for each eccentric and concentric velocity were obtained from the dynamometer data. A seven parameter strength model, which included the effects of involuntary neural inhibition, was fitted to the maximum torque – velocity data for each joint [3]. To assess whether there were significant differences between these subject- specific strength models, the root mean square (RMS) difference between the model and experimental torque – velocity data was computed based on: (i) the subject’s model; and (ii) each of the other subjects’ models. This was done for both absolute and normalised torque values (normalised to maximum isometric torque) to allow differences in the shape of the curves to be differentiated from those due purely to absolute strength. The RMS differences were compared using one-sided independent samples t-tests with significance set at p = 0.05. Table 1. Characteristics of the five elite athletes Subject Sport Age Height (m) Mass (kg) TJ Triple jump 22 1.82 72.6 HJ High jump 24 1.89 81.9 TC Track cycling 25 1.83 86.0 GY Gymnastics 19 1.78 78.5 KA Karate 30 1.75 89.3 RESULTS AND DISCUSSION The strength and power characteristics indicated qualitative and statistically significant differences between athletes (Figure 1 and Table 2). In every case, based on both absolute and normalized torques, the fit of the experimental data to an athletes’ own model was significantly better than the fit to any of the others. These results support previous observations [2] on the subject-specific nature of the strength – speed and power – speed relationships.