The Comparative Analysis of Free Technique Cross Country and Skating on Roller Skies

The skiing is a very old human locomotion on the snow. During the last century, it has became very popular winter and Olympic sport, currently profiting from its great popularity among the public. New cross country skiing technique – skating – has been developing very dynamically since the eighties years of the 20th century. This presented study deals with a comparison of muscles activation during skating technique on skis and on roller skis. We studied three base styles of skating: V-1 on right and left side and V-2. The beginnings of important activation of the muscles on a right leg and their subsequent deactivation during one step cycle were measured with surface electromyography (SEMG). The results confirm the idea that we can consider roller skiing as a special training device of cross country skiing. This is correct from the kinetic view as well as from the connection of muscles. The biggest differences in phase shifts of muscle unit activation were found between V-1 on left side during cross country skiing and roller skiing.Skiing is a very old human activity on snow. During the last century, it has become a very popular winter and Olympic sport, currently profiting from its great popularity among the public. A new cross country skiing technique – skating – has been developing very dynamically since the 1980’s. This presented study deals with a comparison of muscles activation during the skating technique on skis and on roller skis. We studied three base styles of skating: V-1 on right and left side and V-2. The important activation of the muscles on a right leg and their subsequent deactivation during one a step cycle were measured with surface electromyography (SEMG). The results confirm the idea that we can consider roller skiing as a special training device for cross country skiing. This is correct from the kinetic view as well as from the connection of muscles. The biggest difference in phase shifts of muscle unit activation were found between V-1 on left side during cross country skiing and roller skiing

Hypernasality associated with basal ganglia dysfunction: evidence from Parkinson’s disease and Huntington’s disease

Background Although increased nasality can originate from basal ganglia dysfunction, data regarding hypernasality in Parkinson’s disease (PD) and Huntington’s disease (HD) are very sparse. The aim of the current study was to analyze acoustic and perceptual correlates of velopharyngeal seal closure in 37 PD and 37 HD participants in comparison to 37 healthy control speakers. Methods Acoustical analysis was based on sustained phonation of the vowel /i/ and perceptual analysis was based on monologue. Perceptual analysis was performed by 10 raters using The Great Ormond Street Speech Assessment ’98. Acoustic parameters related to changes in a 1/3-octave band centered on 1 kHz were proposed to reflect nasality level and behavior through utterance. Results Perceptual analysis showed the occurrence of mild to moderate hypernasality in 65% of PD, 89% of HD and 22% of control speakers. Based on acoustic analyses, 27% of PD, 54% of HD and 19% of control speakers showed an increased occurrence of hypernasality. In addition, 78% of HD patients demonstrated a high occurrence of intermittent hypernasality. Further results indicated relationships between the acoustic parameter representing fluctuation of nasality and perceptual assessment (r = 0.51, p < 0.001) as well as the Unified Huntington Disease Rating Scale chorea composite subscore (r = 0.42, p = 0.01). Conclusions In conclusion the acoustic assessment showed that abnormal nasality was not a common feature of PD, whereas patients with HD manifested intermittent hypernasality associated with chorea

Selected pairs of the phonatory measures with classification boundary separating HD and HC subjects.

<p>Selected pairs of the phonatory measures with classification boundary separating HD and HC subjects.</p

Scheme depicting the most salient features of dysphonia in HD and their relationship to motor symptoms.

<p>Scheme depicting the most salient features of dysphonia in HD and their relationship to motor symptoms.</p

Overview of the phonatory measurements applied to sustained vowel phonations.

<p>Overview of the phonatory measurements applied to sustained vowel phonations.</p

Results of voice analyses in HD and HC subjects.

*<p><i>p</i><0.05;</p>**<p><i>p</i><0.01;</p>***<p><i>p</i><0.001.</p><p>MPT = maximum phonation time, MPT_VB = maximum phonation time until first break, NVB = number of voice breaks, DUV = degree of voicelessness, F0 SD = variability of fundamental frequency, RPDE = recurrence period density entropy, PPE = pitch period entropy, HNR = harmonics-to-noise ratio, DFA = detrended fluctuation analysis, MFCC = mel-frequency cepstral coefficient.</p