Relationship Between Training Volume and Ratings of Perceived Exertion in Swimmers.

The markers of external training load (ETL), distance and intensity, do not take into account the athletes' psychophysiological stress, i.e., internal training load (ITL). Thus, the aim of this study was to evaluate the relationship between ETL and ITL using the rating of perceived exertion (RPE) and session-RPE in swimmers. Seventeen young swimmers (10 male, 15.8 ± 0.87 yr and 7 female, 15.1 ± 0.46 yr) belonging to one national level youth team took part in this study over 4 wk. The external training load was planned using swimming distance (in meters) at seven different training intensities. Swimmers' RPE was assessed 30 min after each training session. Session-RPE was calculated by multiplying RPE by session duration (min). The relationship between the variables was analyzed with Pearson correlations and a multiple linear regression was performed to predict the session-RPE as a function of the independent variables (aerobic and anaerobic volume). The swimming distance at different intensities correlated strongly with RPE and very largely with session-RPE (.64, p < .05 and .71, p < .05, respectively). Regression analysis indicated that the aerobic and anaerobic volumes together explained more than 50% of the ITL variability. In conclusion, the swimming distance in each training session was significantly associated with RPE and session-RPE in swimmers. In other words, based on these results, the use of high-volume training at lower intensities affects the RPE and Session-RPE more than the anaerobic volume.

The Activity Profile of Young Tennis Athletes Playing on Clay and Hard Courts: Preliminary Data.

The aim of this study was to compare the kinematic characteristics of tennis matches between red clay and hard courts in young tennis players. Eight young tennis players performed two tennis matches on different court surfaces. The match activities were monitored using GPS units. The distance covered in different velocity ranges and the number of accelerations were analyzed. The paired t test and inference based on magnitudes were used to compare the match physical performance between groups. The total distance (24% of difference), high-intensity running distance (15 - 18 km/h) (30% of difference), the number of high-intensity activities (44% of difference), the body load (1% of difference), and accelerations >1.5 g (1.5-2 g and >2 g 7.8 and 8.1 % of difference, respectively) were significantly greater in clay court than hard court matches (p < 0.05). Matches played on the red clay court required players to cover more total and high-intensity running distances and engage in more high-intensity activities than the matches played on the hard court. Finally, on the clay court the body load and the number of accelerations performed (>1.5 g) were possibly higher than on the hard court.