Pre-Practice Hydration Status in Soccer (Football) Players in a Cool Environment.

Background and Objectives: Only a few studies have reported the pre-practice hydration status in soccer players (SPs) who train in a cool climate. The primary purpose of this study was to examine the hydration status of male semiprofessional SPs immediately before their regular training session in winter. The secondary purpose was to compare the urinary indices of the hydration status of Estonian and Latvian SPs. Materials and Methods: Pre-training urine samples were collected from 40 Estonian (age 22.1 ± 3.4 years, soccer training experience 13.7 ± 3.9 years) and 41 Latvian (age 20.8 ± 3.4 years, soccer training experience 13.3 ± 3.0 years) SPs and analyzed for urine specific gravity (USG). The average outdoor temperature during the sample collection period (January⁻March) was between -5.1 °C and 0.2 °C (Estonia) and -1.9 °C and -5.0 °C (Latvia). Results: The average pre-training USG of Estonian and Latvian SPs did not differ (P = 0.464). Pooling the data of Estonian and Latvian SPs yielded a mean USG value of 1.021 ± 0.007. Hypohydration (defined as a USG ≥ 1.020) was evident altogether in fifty SPs (61.7%) and one of them had a USG value greater than 1.030. Conclusions: Estonian and Latvian SPs do not differ in respect of USG and the prevalence of pre-training hypohydration is high in this athletic cohort. These findings suggest that SPs as well as their coaches, athletic trainers, and sports physicians should be better educated to recognize the importance of maintaining euhydration during the daily training routine in wintertime and to apply appropriate measures to avoid hypohydration.

Shoulder rotator muscle dynamometry characteristics: side asymmetry and correlations with ball-throwing speed in adolescent handball players.

THE AIM OF THE INVESTIGATION WAS TO: 1) compare shoulder external/internal rotator muscles' peak torques and average power values and their ratios in the dominant and non-dominant arm; 2) determine correlations between shoulder rotator muscles' peak torques, average power and ball-throwing speed in handball players. Fourteen 14 to 15-year-old male athletes with injury-free shoulders participated in the study (body height: 176 ± 7 cm, body mass 63 ± 9 kg). The tests were carried out by an isokinetic dynamometer system in the shoulder internal and external rotation movements at angular velocities of 60°/s, 90°/s and 240°/s during concentric contractions. The eccentric external- concentric internal rotator muscle contractions were performed at the velocity of 90°/s. The player threw a ball at maximal speed keeping both feet on the floor. The speed was recorded with reflected light rays. Training in handball does not cause significant side asymmetry in shoulder external/internal rotator muscle peak torques or the average power ratio. Positive correlations between isokinetic characteristics of the shoulder internal and external rotator muscles and ball-throwing speed were determined. The power produced by internal rotator muscles during concentric contractions after eccentric contractions of external rotator muscles was significantly greater in the dominant than in the non-dominant arm. Thus, it may be concluded that the shoulder eccentric external/concentric internal rotator muscle power ratio is significantly greater than this ratio in the concentric contractions of these muscles.

Ankle joint evertor-invertor muscle torque ratio decrease due to recurrent lateral ligament sprains.

OBJECTIVE: To determine an ankle inversion-eversion movement range part where evertor/invertor muscles torque ratio is altered after recurrent ankle lateral ligament sprains. DESIGN: The ankle evertor/invertor muscles torque ratios were determined in the different range parts of angular positions by the muscle isokinetic movements. BACKGROUND: It is important to determine the movement range part where the evertor muscle weakness after the ankle lateral ligament sprains is more expressed and a repeated trauma of the lateral ligaments is more probable. METHODS: Twenty-eight male handball players participated in the tests using an ankle isokinetic inversion-eversion movement investigation dynamometer system. Thirty-three ankle joints were uninjured, but 23 underwent recurrent lateral ligament sprains. RESULTS: The ankle evertor/invertor muscles torque ratio for the sprained ankles was significantly lower in comparison with the uninjured joints in inversion positions at 50 degrees and 60 degrees of the range of movements in all applied velocities, except the slowest movement (30 degrees /s). CONCLUSIONS: The recurrent ankle lateral ligament sprains reduced the evertor/invertor muscles torque ratio in the inversion positions of the range of movements and therefore the evertor muscle weakness was more expressed in the beginning of the eversion movement.