The aim of the study was to develop a method for measurement and analysis of kinematics of the pelvic girdle movement in breaststroke swimming to support training of technical skills. The measurements were performed in five elite breaststroke swimmers. A recording device for triaxial accelerations and triaxial rotational angular velocity was mounted on the dorsal part of the pelvic girdle of the athlete. The task of the athlete was to swim one length of the 50 m swimming pool with the intensity similar to competition. From the consecutive cycles of swimming motion, we developed individual mean graphical and numerical profiles of the kinematics of the pelvic girdle movement within the average cycle. Mean basic values of the characteristics were compared with the values documented in the literature obtained by means of the video analysis or using the method of measurement of the velocity of the unwound rope. The comparison revealed that the results in the group studied were very similar to the results obtained using other methods and were typical of elite athletes. Analysis of the motion profiles for the pelvic girdle in breaststroke swimmers indicated that the results obtained reflected individual technique of performing individual phases of swimming cycles. The proposed measurement method, presentation and analysis of the profile of the pelvic girdle motion in breaststroke swimming represents a good tool for fast and effective biomechanical evaluation of motion technique components.

The ability to produce force rapidly has the potential to directly influence sprinting performance through changes in stride length and stride frequency. This ability is commonly referred to as the rate of force development (RFD). For this reason, many elite sprinters follow a combined program consisting of resistance training and sprint training. The purpose of this study was to investigate the strength, endocrine and body composition adaptations that occur during distinct phases of a block periodized training cycle in a 400 m Olympic level sprinter. The athlete is an elite level 400 m male sprinter (age 31 years, body mass: 74 kg, years of training: 15 and Personal Best (PB): 45.65 s). This athlete completed four distinct training phases of a block periodized training program (16 weeks) with five testing sessions consisting of testosterone:cortisol (T/C) profiles, body composition, vertical jump, and maximum strength testing. Large fluctuations in T/C were found following high volume training and the taper. Minor changes in body mass were observed with an abrupt decrease following the taper which coincided with a small increase in fat mass percentage. Jump height (5.7%), concentric impulse (9.4%), eccentric impulse (3.4%) and power ratio (18.7%) all increased substantially from T1 to T5. Relative strength increased 6.04% from T1 to T5. Lastly, our results demonstrate the effectiveness of a competitive taper in increasing physiological markers for performance as well as dynamic performance variables. Block periodization training was effective in raising the physical capabilities of an Olympic level 400 m runner which have been shown to directly transfer to sprinting performance.