Differences in game acts at the baseline among youth and adult categories in tennis

Title: Differences in game acts at the baseline among youth and adult categories in tennis. Goals: The aim is to find out where on the court the players move in time of hitting the ball, if they "circle it" and to what extent. We'll compare the results through youth and adult categories. Method: Using a structured observation we observed the position of the players during the match on the court and the representation of single strokes during the game. Results: The results show the differences in game acts among all categories: the position of the player during the hit of the ball, the percentage of forehands and backhands in the game and success and effectiveness of strokes from the baseline. Key words: tennis, efficiency, success, stroke positio

Differences in game acts at the baseline in men and juniors in tennis.

Sportovní hryFaculty of Physical Education and SportFakulta tělesné výchovy a sport

The Quality of Frozen-thawed Canine Semen With Respect to Semen Extender Composition and Sequence of Ejaculate Collection in Dogs

The aim of this study was to evaluate the effect of clarified egg yolk addition to semen extender, and the semen collection sequence on the quality of frozen-thawed semen in dogs. Semen was collected from 6 dogs in a time interval of 24 hours. As parameter of the quality of frozen-thawed (F-T) semen, the motility by computer assisted sperm analysis (CASA) and plasma membrane integrity by hypo-osmotic swelling test (HOS) were evaluated. All kinematic parameters of sperm motility were higher in F-T samples containing the whole in comparison to the clarified egg yolk. The sequence of semen collection affected sperm movement characteristics of native as well as F-T semen, but it was not possible to determine whether the fresh semen from the 1st or 2nd collection is of higher quality. All motility parameters of sperms frozen with extender containing the whole egg yolk were significantly higher in the case of the 2nd collection. The situation was not so clear in the case of clarified egg yolk addition, but the velocity values were higher in F-T samples from the 2nd collection. In contrast to proven differences in motility, the effect of the addition of clarified egg yolk and the sequence of semen collection were not projected at all on the quality of plasma membrane of canine sperms evaluated by HOS test

sIgA concentration of puppies and adults taken before acute stress and 20 min after the start (adjusted means ± S.E.).

<p>^†P<0.1, ^*P<0.05, ^**P<0.01.</p

Salivary cortisol concentration of puppies and adults taken before acute stress and 20 min after the start of acute stress after logarithmic transformation (adjusted means ± S.E.).

<p>^*P<0.05.</p