20.500.12556/RUL-190579 Vpliv različnih verbalnih navodil na aktivacijo mišic trupa Effect of Different Verbal Instructions on Trunk Muscle Activity Ustrezna aktivacija mišic trupa je pomembna za zagotavljanje togosti trupa med vsakodnevnimi in športnimi dejavnostmi. Medtem ko številne študije primerjajo različne tehnike aktivacije mišic trupa, je raziskav o učinkih različnih verbalnih navodil na aktivnost teh mišic manj. Namen raziskave je bil primerjati učinke različnih verbalnih navodil na aktivnost mišic trupa. Cilji magistrskega dela so bili: (1) primerjava amplitud elektromiografskega signala (EMG) mišic trupa med hotenim naprezanjem ob uporabi različnih verbalnih navodil, (2) primerjava mišične koaktivacije med različnimi verbalnimi navodili ter (3) primerjava amplitud EMG in mišične koaktivacije pri posameznem verbalnem navodilu med dvema položajema (stoja in sed). V raziskavi smo primerjali aktivnost mišic m. erector spinae (ES), mm. multifidi (Mf), m. transversus abdominis v kombinaciji z mišico m. obliquus internus abdominis (TrA + IO) in mišice m. obliquus externus abdominis (EO). Poleg tega smo primerjali razmerji aktivacije mišic EO / (TrA + IO) in Mf / (TrA + IO) med hotenim naprezanjem ob uporabi različnih verbalnih navodil v dveh položajih: v stoji s predročenjem uteži in v sedečem položaju. Izvedli smo presečno raziskavo, v katero smo vključili 24 preizkušancev (12 moških in 12 žensk), starih 23,6 ± 2,8 leta, katerih indeks telesne mase je znašal 22,8 ± 2,7 kg/m². Mišično aktivnost smo merili s površinsko elektromiografijo in jo izrazili kot odstotek (%) največjega hotenega izometričnega naprezanja. Uporabili smo pet verbalnih navodil: »Maksimalno napnite trebušne mišice« (»Napni«), »Maksimalno povlecite popek proti hrbtenici« (»Popek«), »Nekdo vas bo udaril v trebuh, upirajte se maksimalno« (»Boks«), »Položite roke v bok in maksimalno potisnite prste narazen« (»Prsti«) ter »Zakašljajte in maksimalno zadržite pritisk, ki ga v trupu začutite ob kašlju« (»Kašelj«). Za analizo razlik med verbalnimi navodili in položajema smo uporabili enosmerno in dvosmerno analizo variance. Med različnimi verbalnimi navodili nismo ugotovili statistično značilnih razlik v aktivnosti mišic. Statistično značilne razlike v mišični aktivnosti med položajema (stoja in sed) smo ugotovili pri vseh mišicah, razen pri mišici TrA + IO ob uporabi navodil »Napni«, »Popek« in »Boks«. Pri vseh preostalih kombinacijah mišic in verbalnih navodil je bila mišična aktivnost statistično značilno večja v stoji s predročenjem uteži kot v sedečem položaju. Pri analizi glede na spol smo v sedečem položaju ugotovili statistično značilno interakcijo med verbalnim navodilom in spolom pri mišici EO. Interakcija je bila povezana z navodilom »Kašelj«: pri moških je bila ob tem navodilu aktivnost mišice EO najmanjša, pri ženskah pa največja. Ker med različnimi verbalnimi navodili nismo ugotovili statistično značilnih razlik v aktivnosti mišic trupa, lahko pri vadbi za krepitev oziroma aktivacijo mišic trupa uporabljamo različna navodila, pri čemer je smiselno več pozornosti nameniti položaju telesa, saj je bila mišična aktivnost večinoma večja v stoji kot v sedečem položaju. Appropriate trunk muscle activation is important for maintaining trunk stiffness during activities of daily living and sports. While numerous studies have compared different trunk muscle activation techniques, fewer studies have investigated the effects of different verbal instructions on trunk muscle activity. The aim of this study was to compare the effects of different verbal instructions on trunk muscle activity. The objectives were to: (1) compare trunk muscle electromyographic (EMG) signal amplitudes during voluntary exertion under different verbal instructions; (2) compare muscle coactivation between different verbal instructions; and (3) compare EMG amplitudes and muscle coactivation between two body positions (standing and sitting) for each verbal instruction. The study compared the activity of the m. erector spinae (ES), mm. multifidi (Mf), m. transversus abdominis in combination with the m. obliquus internus abdominis (TrA + IO), and the m. obliquus externus abdominis (EO). In addition, the muscle activation ratios EO / (TrA + IO) and Mf / (TrA + IO) were compared during voluntary exertion under different verbal instructions in two positions: standing while holding weights with the arms extended forward and sitting. A cross-sectional study was conducted involving 24 participants (12 men and 12 women), with a mean age of 23.6 ± 2.8 years and a mean body mass index of 22.8 ± 2.7 kg/m². Muscle activity was measured using surface electromyography and expressed as a percentage (%) of maximal voluntary isometric contraction (MVIC). Five verbal instructions were used: »Maximally tighten your abdominal muscles« (»Tighten«); »Maximally pull your navel toward your spine« (»Navel«); »Someone is going to punch you in the abdomen; resist maximally« (»Boxing«); »Place your hands on your hips and maximally push your fingers apart« (»Fingers«); and »Cough and maximally maintain the pressure you feel in your trunk when coughing« (»Cough«). One-way and two-way analyses of variance were used to analyze differences between verbal instructions and body positions. No statistically significant differences in muscle activity were found between verbal instructions. Statistically significant differences in muscle activity between body positions (standing and sitting) were observed for all muscles except TrA + IO under the »Tighten«, »Navel«, and »Boxing« instructions. For all remaining muscle–instruction combinations, muscle activity was significantly greater when standing with the arms extended forward while holding weights than when sitting. In the sex-specific analysis, a statistically significant interaction between verbal instruction and sex was found for EO activity in the sitting position. This interaction was associated with the »Cough« instruction: EO activity under this instruction was the lowest of all instructions in men and the highest in women. As no statistically significant differences in trunk muscle activity were found between verbal instructions, different instructions may be used during exercises aimed at strengthening or activating the trunk muscles. However, greater attention should be paid to body position, as muscle activity was generally greater in standing than in sitting. verbalna navodila mišice trupa elektromiografija stabilizacija trupa Verbal instruction Abdominal muscles Electromyography Core stability true false false Slovenski jezik Angleški jezik Magistrsko delo/naloga 2026-10-30 07:16:32 2026-10-30 07:16:41 2026-10-31 04:34:00 0000-00-00 00:00:00 2026 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 1970-01-01 72623 38146.pdf 38146.pdf 1 84934D1E2D485AFC3928DAE06614C5DE e33a6e973bb07d31c8b60d620a9c5ecb8595459a4c8dd7f6c010413756c93926 6f37e283-d429-11f1-aea2-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=252089 Fakulteta za šport 0 0 0