Search results for "Motor activity"
showing 10 items of 486 documents
Effects of cerebellar TMS on motor cortex of patient with focal dystonia: a preliminary report
2008
Recent evidence suggests a role for cerebellum in pathophysiology of dystonia. Here we explored, the cerebellar modulation of motor cortex in patients with focal upper limb dystonia. Eight patients and eight controls underwent a transcranial magnetic stimulation protocol to study the cerebellar-brain-inhibition (CBI): a conditioning cerebellar stimulus (CCS) was followed 5 ms after by the contralateral motor cortex stimulation (test stimulus: TS). We explored the effects of CBI on MEP amplitude, short intracortical inhibition (SICI) and intracortical facilitation (ICF) measures. At baseline no differences in TS-MEP amplitude, SICI or ICF were found between patients and controls. Cerebellar-…
Gait-dependent motor memory facilitation in covert movement execution
2004
In the current study, we examined whether sensorimotor information stored in short-term memory may influence the temporal features between overt and covert execution of human locomotor movements and, furthermore, to examine to what extent such influence may depend on the ongoing gait activity. The subjects (n=20) who participated in the experiment were separated in two groups and instructed to walk (overt execution) or imagine walking (covert execution) along three locomotor paths: horizontal, uphill and downhill. The subjects of the first group, labeled in block, performed all the covert trials before executing the corresponding overt trials, while the subjects of the second group, labeled…
Case study: effect of handrim diameter on performance in a paralympic wheelchair athlete.
2009
This study, with a top T-52 class athlete, determines the relationship between stroke frequency (SF) and push time (PT) and wheelchair velocity (Wv) using different handrim diameters (HD) and the effect of different HDs on the athlete’s heart rate (HR) and blood lactate (LACT) at competition speeds. Wv shows a linear-direct relationship with SF but a linear-inverse relationship with PT (p < .001 in both cases). Using bigger handrims (0.37 m instead of 0.36 m), SF increases 6%, while PT decreases 27% (at 24 Km·h–1). HR (p < .0001) increases with Wv and is also affected by HD with differences between the 0.34 m—0.36 m handrim group (lower values) and the 0.37 m handrim (higher values). …
Physical activity, morbidity and mortality in twins: a 24-year prospective follow-up.
2010
The aim of this study was to find out whether persistent leisure-time physical activity, adjusted for genetic liability and childhood experiences, protect against occurrence of specific chronic diseases and all-cause mortality. Study design was a 24-year prospective follow-up after 6-year physical activity discordance in twin pairs. From 5,663 healthy adult twin pairs, 146 pairs (including 29 mozygotic) discordant for both intensity and volume of leisure physical activity at baseline in both 1975 and 1981 were systematically identified. Mortality and occurrence of chronic diseases (diabetes, hypertension, coronary heart disease defined according to reimbursable medication status) were follo…
Brain slow waves preceding time-locked visuo-motor performance.
1993
According to previous findings (Konttinen and Lyytinen, 1992), the slow brain negativity preceding the trigger pull in rifle‐shooting tends to be decreased in successful shots among experienced marksmen, whereas no such pattern is found among inexperienced subjects. This effect was interpreted as resulting mainly from optimal arousal. However, another explanation is examined here. The aim of the experiment was to investigate slow electrocortical changes associated with motor regulation and visual aiming related to shooting performance. Four variations on a shooting task were used, in which the visual and motor components were contrasted. Motor activity related to gun stabilization was found…
Stage of change and motivation to healthier lifestyle in non-alcoholic fatty liver disease.
2013
Backgrounds & Aims: Healthy diet and physical activity are the treatment cornerstones of non-alcoholic fatty liver disease (NAFLD); their effectiveness is however limited by difficulties in implementing lifestyle changes. We aimed at determining the stage of change and associated psychological factors as a prerequisite to refine strategies to implement behavior changes. Methods: We studied 138 consecutive NAFLD patients (73% male, age 19-73 years). The diagnosis was confirmed by liver biopsy in 64 cases (steatohepatitis, 47%). All cases completed the validated EMME-3 questionnaire, consisting of two parallel sets of instruments (for diet and physical activity, respectively) and providing st…
TIME-OF-DAY EFFECTS ON THE INTERNAL SIMULATION OF MOTOR ACTIONS: PSYCHOPHYSICAL EVIDENCE FROM POINTING MOVEMENTS WITH THE DOMINANT AND NON-DOMINANT A…
2010
It is well known that circadian rhythms modulate human physiology and behavior at various levels. However, chronobiological data concerning mental and sensorimotor states of motor actions are still lacking in the literature. In the present study, we examined the effects of time-of-day on two important aspects of the human motor behavior: prediction and laterality. Motor prediction was experimentally investigated by means of imagined movements and laterality by comparing the difference in temporal performance between right and left arm movements. Ten healthy participants had to actually perform or to imagine performing arm-pointing movements between two targets at different hours of the day …
Brain Slow Potentials Reflecting Successful Shooting Performance
1995
Preparatory brain activity from frontal, centro-lateral, and occipital areas were recorded from top-level rifle shooters during shooting performance. The aim of the study was to examine the relation of brain slow potentials to qualitative (rifle holding) and quantitative (hit) aspects of superior shooting performance. For this purpose, a typology of slow potentials (SPs) was developed. The resulting SP types were used for unraveling the associations between the electrocortical activity and behavioral output. The main finding was that frontal positivity was associated with successful performance, but only if the central-right SP was more negative than the central-left one. This finding was e…
Daily steps among Finnish adults: Variation by age, sex, and socioeconomic position
2011
Aims: The aim of this study was to provide descriptive population-based pedometer data from adults aged 30-45 years in Finland, and to compare daily step counts with evidence-based indices. Methods: The data was collected from 1853 participants in 7 consecutive days in winter 2007—08 in part of 27-year follow up of the Cardiovascular Risk in Young Finns study. Results: The participants took (mean±standard deviation) 7499 ± 2908 steps/day. Step counts included 1925 ± 2052 aerobic steps/day gathered in bouts of at least 10 min continuous ambulatory activity. Women had more total steps than men ((7824 ± 2925 vs. 7089 ± 2774; p < 0.001). Although participants had higher mean total steps on …
Knee and ankle joint stiffness in sprint running.
2002
Stiffness has often been considered as a regulated property of the neuromuscular system. The purpose of this study was to examine the ankle and knee joint stiffness regulation during sprint running.Ten male sprinters ran at the constant relative speeds of 70, 80, 90, and 100% over a force platform, and ground reaction forces, kinematic, and EMG parameters were collected.The results indicated that with increasing running speed the average joint stiffness (change in joint moment divided by change in joint angle) was constant (7 N x m x deg(-1)) in the ankle joint and increased from 17 to 24 N x m x deg(-1) (P0.01) in the knee joint.The observed constant ankle joint stiffness may depend on (co…