Thigh muscle function in stroke patients revealed by velocity-encoded cine phase-contrast magnetic resonance imaging.
Current methods of clinical assessment of muscle coordination and function after stroke do not provide information on deep muscles. The objective of this study was to examine how stroke affects both superficial and deep muscles' coordination and whether muscle function improves after rehabilitation. Muscle function, coordination, and activity of quadriceps femoris (QF) and hamstrings were evaluated in 10 stroke patients with mild hemiparesis and in 6 controls using velocity-encoded cine phase-contrast magnetic resonance imaging (VE-PC MRI), surface electromyography (sEMG), and maximal voluntary isometric contraction torque (MVC). At baseline, the peak muscle velocity of the rectus femoris (…
Muscle Inactivity and Activity Patterns after Sedentary-Time Targeted Randomized Controlled Trial
Purpose: Interventions targeting sedentary time are needed. We used detailed EMG recordings to study the short-term effectiveness of simple sedentary time-targeted tailored counseling on the total physical activity spectrum. Methods: This cluster randomized controlled trial was conducted between 2011 and 2013 (InPact, ISRCTN28668090), and short-term effectiveness of counseling is reported in the present study. A total of 133 office workers volunteered to participate, from which muscle activity data were analyzed from 48 (intervention, n = 24; control, n = 24). After a lecture, face-to-face tailored counseling was used to set contractually binding goals regarding breaking up sitting periods …
Voimaharjoittelun vaikutukset keskimmäisen ja suoran reisilihaksen väliseen dynamiikkaan polven koukistus-ojennusliikkeessä
Tässä tutkimuksessa tarkastellaan nopeuskoodatun magneettikuvauksen avulla voimaharjoittelun vaikutuksia nelipäisen reisilihaksen mekaniikkaan. Tutkimukseen osallistui 14 koehenkilöä, joista seitsemän voimaharjoitteli 20 viikon ajan. Yhden toiston maksimitulos jalkakyykyssä parani koeryhmällä (33,1 ± 12,1) % ja vertailuryhmällä (6,6 ± 5,1) %. Molemmat tulokset olivat tilastollisesti merkitseviä (koeryhmä 𝑝 < 0.001, vertailuryhmä 𝑝 < 0.05). Ryhmän ja ajan yhteisvaikutus oli merkitsevä (𝑝 < 0.001). Voimaharjoittelujaksoa ennen ja sen jälkeen koehenkilöt tekivät pienellä kuormalla toistuvaa polven ojennus-koukistusliikettä magneettikuvauslaitteessa. Suoran reisilihaksen ja keskimmäisen reis…
Mechanical behavior of the quadriceps femoris muscle tendon unit during low-load contractions
We examined the relationships between morphology and muscle-tendon dynamics of the quadriceps femoris muscle of 11 men using velocity-encoded phase-contrast magnetic resonance imaging (MRI). Thigh muscle electromyography and joint range of motion were first measured outside the MRI scanner during knee extension-flexion tasks that were performed at a rate of 40 times/min with elastic bands providing peak resistance of 5.2 kp (SD 0.4) to the extension. The same movement was repeated inside the MRI scanner bore where tissue velocities and muscle morphology were recorded. The average displacement in the proximal and distal halves of the rectus femoris and vastus intermedius aponeuroses was dif…
Relationship between habitual physical activity and gross motor skills is multifaceted in 5- to 8-year-old children
Adequate motor skills are essential for children participating in age-related physical activities, and gross motor skills may play an important role for maintaining sufficient level of physical activity (PA) during life course. The purpose of this study was to examine the relationship between gross motor skills and PA in children when PA was analyzed by both metabolic- and neuromuscular-based methods. Gross motor skills (KTK--Korperkoordinationstest fur Kinder and APM inventory--manipulative skill test) of 84 children aged 5-8 years (53 preschoolers, 28 girls; 31 primary schoolers, 18 girls) were measured, and accelerometer-derived PA was analyzed using in parallel metabolic counts and neur…
Muscle Activity and Inactivity Periods during Normal Daily Life
Recent findings suggest that not only the lack of physical activity, but also prolonged times of sedentary behaviour where major locomotor muscles are inactive, significantly increase the risk of chronic diseases. The purpose of this study was to provide details of quadriceps and hamstring muscle inactivity and activity during normal daily life of ordinary people. Eighty-four volunteers (44 females, 40 males, 44.1±17.3 years, 172.3±6.1 cm, 70.1±10.2 kg) were measured during normal daily life using shorts measuring muscle electromyographic (EMG) activity (recording time 11.3±2.0 hours). EMG was normalized to isometric MVC (EMGMVC) during knee flexion and extension, and inactivity threshold o…