Homosporticus

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Authors: Denis Causevic, Semso Ormanovic, Ivor Doder and Nedim Covic

The aim of this study was to investigate habits and opinions on dietary supplements intake among male fitness users with nonprofes- sional sport background from Sarajevo - Bosnia and Herzegovina. Overall, sample consisted of 564 participants aged 18-40. Designed questionnaire was used to gain results in 7 largest fitness facilities in Sarajevo. Descriptive cross-sectional analysis was used to ana- lyze results of the questionnaire. Dietary supplements were used by 71,81% (n = 405), of which 46,81% (n = 264) used them on daily basis, while 25.00% (n = 141) participants consumed supplements occasionally. Whey protein (50.37%) was most common choice, followed by amino acid (17.78%) and creatine (14.07%). Muscle gain (59.75%) was the main reason for supplementation usage with 40% of subjects (n=303) enquiring basic information's about supplements trough web search. Therefore, we conclude that additional effort in educating consumers and employees working with fitness users is essential.

7

Authors: Nikolina Gerdijan, Dušan Perić and Elvir Kazazović

The sample of ten young healthy subjects, male, age 20, 21 (students of the Faculty of Sports, University of Banja Luka, Bosnia and Herzegovina ), were examined for the effect of dynamic and static stretching on exercise of force and power of quadriceps and ham- string muscle of the dominant leg knee joint. Using the isokinetic dynamometer, both muscle groups were diagnosed with variables: maximum torque (force), relative torque, explosive force and relative power. Measurements were carried out under conditions of slow (60°/s) and fast speed (240°/s) contractions. The same measurement protocols were implemented in three experimental situations: without the initial stretching (WS), after the dynamic stretching (D) and after the static stretching (S). Results of statistical analysis show that both types of expansion lead to an increase of force and power of hamstring and quadriceps (quadriceps 60°/s: WS - 2,67 Nm/kg, D - 3,06 Nm/kg , S -3,05 Nm/kg; hamstring 60°/s: WS -2,25 Nm/kg , D -2,41 Nm/kg , S- 2,41 Nm/kg; quadriceps 240°/s: WS- 1,42 Nm/kg , D- 1,70 Nm/kg , S- 1,64 Nm/kg; hamstring 240°/s: WS -1,51 Nm/kg , D- 1, 85 Nm/kg , S - 1, 71 Nm/kg). Looking at the results, both group of muscle (quadriceps and hamstring) produced greater explosive force at a speed of 60°/s after the static stretching. (Quadriceps: WS- 158,99 Nm, D- 188,13 Nm, S- 188,72 Nm; hamstring: WS- 149,53 Nm, D-156,67 Nm, S-164,00 Nm). Both group of muscle produced greater explosive force at the speed of 240°/s after the dynamic stretching (quadriceps: WS-106,75 Nm ,D- 131, 50 Nm, S- 126,30 Nm; hamstring : WS- 114,41 Nm, D-139,02 Nm, S-129,43 Nm). This indicates that static and dy- namic stretching have positive acute effects when applied before the activities in which the rate of contraction is small and external resistance is large, while only dynamic stretching has a positive effect when it precedes the activities of higher muscle contraction speed. Regardless of the elongation model applied, quadriceps is the dominant muscle group during the slow contractions (60°/s), while at high speeds, the role of hamstring significantly increases.