Eighteen years' experience applying old and current strategies in the pre-participation cardiovascular screening of athletes.

INTRODUCTION: Cardiovascular pre-participation screening (PPS) is recommended for the identification of athletes at risk for sudden cardiac death. However, there is currently no universally accepted screening protocol. METHODS: Two distinct PPS strategies were studied in a large cohort of Greek athletes (5 to 39 years old): PPS I, with routine 12-lead ECG and echo, in addition to personal and family history, and physical examination; and PPS II, without routine echo. PPS I (12,353 athletes) was performed from 1992 to 2002, and PPS II (9852 athletes) from 2003 to 2010. RESULTS: "Abnormal" findings were observed in 49.3% of the athletes (49.6% in PPS I and 48.9% in PPS II, p=0.299). Most of them were age- or exercise-related. Further evaluation was recommended for 8.3% of the athletes. Finally, 39 athletes (22 from PPS I) were excluded from competitive sports. Hypertrophic cardiomyopathy was found in 7 athletes. Other abnormalities were: dilated cardiomyopathy; complete heart block; coronary artery disease; Wolf-Parkinson-White syndrome; and severe hypertension. The ECG played a critical role in the exclusion of 13 athletes, compared to only one for echo. Both PPS methods revealed an almost equal incidence of findings. CONCLUSIONS: We suggest that the routine use of ECG alone is sufficient for the successful screening of athletes.

The duration of the inhibitory effects with static stretching on quadriceps peak torque production.

Although several studies have investigated the acute effect of static stretching exercises, the duration of exercises that negatively affects performance has not been ascertained. This study was conducted to determine the acute effect of different static stretching durations on quadriceps isometric and isokinetic peak torque production. The 50 participants were randomly allocated into five equivalent sized groups and were asked to perform a stretching exercise of different duration (no stretch, 10-second stretch, 20-second stretch, 30-second stretch, and 60-second stretch). The knee flexion range of motion and the isometric and concentric isokinetic peak torques of the quadriceps were measured before and after a static stretching exercise in the four experimental groups. The same parameters were examined in the control group (no stretch) without stretching, before and after a 5-minute passive rest. There were no significant differences among groups before the experimentation regarding their physical characteristics and performances (P > 0.05). These results reflect the different groups' homogeneity. Significant knee joint flexibility increases (P < 0.001) and significant isometric and isokinetic peak torque reductions (P < 0.05-0.001) have been shown to occur only after 30 and 60 seconds of quadriceps static stretching. Stretching reduced isometric peak torque by 8.5% and 16.0%, respectively. Concerning isokinetic peak torque after 30 and 60 seconds of stretching, it was reduced by 5.5% vs. 11.6% at 60 degrees/s and by 5.8% vs. 10.0% at 180 degrees/s. We suggest that torque decrements are related to changes of muscle neuromechanical properties. It is recommended that static stretching exercises of a muscle group for more than 30 seconds of duration be avoided before performances requiring maximal strength.