Učinek lokalnega mišičnega utrujanja evertorjev stopala na zaznavo mišične sile in živčno-mišično aktivacijo : magistrsko delo

Tučen, Taja (author), Kacin, Alan (mentor), Brezovar, Tjaž (comentor), Umek, Nejc (reviewer)

Uvod: Zaznavanje mišične sile pomeni sposobnost posameznika, da natančno prepozna velikost sile med prostovoljno mišično kontrakcijo in poljubno silo lahko tudi natančno poustvari. Evertorji gležnja imajo pomembno vlogo pri aktivni stabilizaciji gležnja, zato je ustrezno zaznavanje njihove mišične sile pomembno. Utrujanje mišic je fiziološki pojav, ki prehodno zmanjša sposobnosti razvoja maksimalne mišične sile. Razumevanje sprememb v zaznavanju mišične sile, povzročenih z utrujanjem mišic, bi lahko prispevalo k boljšemu razumevanju, kako ohranjati optimalno funkcijo gležnja. Namen: Namen magistrskega dela je bil ovrednotiti učinek lokalnega mišičnega utrujanja na zaznavanje mišične sile in živčno-mišično aktivacijo evertorjev stopala pri zdravih osebah. Metode dela: V raziskavo smo vključili 24 oseb ženskega in moškega spola, starih med 21 in 33 let. Testiranja smo opravili na računalniško vodenem izokinetičnem dinamometru. Med izvajanjem dinamometričnih meritev smo s površinsko EMG merili aktivacijo mišic tibialis anterior, peroneus longus, soleus in medialne glave mišice gastrocnemius. Za analizo dinamometričnih podatkov smo uporabili faktorsko 2 × 2 (pogoj × sila) analizo variance (ANOVA) za ponovljive meritve in t-test za parne vzorce, za analizo EMG meritev pa neparametričen Friedman-ov test. Rezultati: Variabilna napaka zaznavanja mišične sile z vidno povratno informacijo pri 25 % maksimalne hotene izometrične kontrakcije (MVIC) ni bila značilno različna (p = 0,325) med spočitim in utrujenim stanjem, pri 50 % MVIC pa je bila razlika značilna (p = 0,030). Razlika v variabilni napaki zaznavanja mišične sile brez vidne povratne informacije ter razlika v konstantni napaki sta bili tako pri 25 % kot pri 50 % MVIC statistično neznačilni (p > 0,05). EMG aktivacija utrujene mišice peroneus longus je bila značilno večja med testom zaznavanja mišične sile z in brez vidne povratne informacije tako pri 25 % (p = 0,005; 0,001) kot pri 50 % MVIC (p = 0,010; 0,001), podoben trend spremembe aktivacije je bil zaznan tudi za mišico tibialis anterior. Zaključek: Kljub pomembnemu povečanju živčno-mišične aktivacije m. peroneus longus in m. tibialis anterior, se variabilnost v zaznavanju mišične sile evertorjev stopala brez vidne povratne zanke z utrujanjem ne spremeni pomembno.

• Language: Slovenian
• Keywords: magistrska dela, fizioterapija, zaznavanje mišične sile, mišično utrujanje, evertorji stopala
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: ZF - Faculty of Health Sciences
• Place of publishing: Ljubljana
• Publisher: [T. Tučen]
• Year: 2025
• Number of pages: 45 str., [5] str. pril.
• PID: 20.500.12556/RUL-168349
• UDC: 615.8
• COBISS.SI-ID: 232045827
• Publication date in RUL: 10.04.2025

Secondary language

• Language: English
• Title: Effect of local muscle fatigue of foot evertors on muscle force sense and neuromuscular activation : master thesis

Abstract

Introduction: Muscle force sense refers to the ability of an individual to accurately recognize the magnitude of the force during voluntary muscle contraction and to accurately reproduce it. Foot evertors play an important role in actively stabilising the ankle, so proper muscle force sense is important. Muscle fatigue is a physiological factor that temporarily reduces the ability to develop maximal muscle force. Understanding the changes in muscle force sense and neuromuscular control that occur as a result of muscle fatigue could contribute to a better understanding of how to maintain optimal ankle function. Purpose: The purpose of this study was to evaluate the effect of local muscle fatigue on muscle force sense and neuromuscular activation of foot evertors in healthy subjects. Methods: 24 male and female subjects aged between 21 and 33 years were included in the study. Testing was performed on a computer-controlled isokinetic dynamometer in two phases. During the dynamometric measurements, surface EMG was used to measure the activation of the tibialis anterior, peroneus longus, soleus and medial head of the gastrocnemius muscles. Factorial 2 × 2 (condition × force) analysis of variance (ANOVA) for repeated measures and paired-samples t-test were used to analyse the dynamometric data and nonparametric Friedman test was used to analyse the EMG measurements. Results: The variable error of muscle force perception with visual feedback at 25% of maximal voluntary isometric contraction (MVIC) was not significantly different (p = 0.325) between the resting and fatigued states, but the difference was significant at 50% MVIC (p = 0.030). The difference in the variable error of muscle force perception without visual feedback and the difference in constant error were statistically insignificant at both 25% and 50% MVIC (p > 0.05). EMG activation of the fatigued peroneus longus muscle was significantly greater during the muscle force perception test with and without visual feedback at both 25% (p = 0,005; 0,001) and 50% MVIC (p = 0,010; 0,001), and a similar trend in activation change was also detected for the tibialis anterior muscle. Conclusion: Despite the significant increase in neuromuscular activation of the peroneus longus muscle and tibialis anterior muscle with fatigue, the variability in muscle force perception of the evertors of the foot without visual feedback does not change significantly

• Keywords: master's theses, physiotherapy, muscle force sense, muscle fatigue, foot evertors