Entropy balance
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Ballet training has been reported to positively influence balance ability. It is not entirely clear how improved balance ability manifests under standing conditions with different demands on postural control. The aim of the study was to compare balance of ballet dancers and non-dancers in a unipedal stance under different conditions. Twenty-five professional ballet dancers and twenty-five controls completed four unipedal standing balance tests: firm surface with eyes open and closed; foam mat surface with eyes open; and firm surface with eyes open immediately after performing ten 360° whole-body turns. The centre of pressure (COP) data were obtained with a force platform and the direction-specific standard deviations, velocities, and sample entropy of the COP displacement were computed. A three-way analysis of variance was used to compare groups, genders, and conditions. For standing immediately after performing ten turns, the postural sway parameters were significantly larger in the control group compared to the ballet dancers in both men and women. In this stance condition the values of postural sway and COP velocities in the control group were larger in the men compared to the women. For both genders in the control group all postural sway and COP velocity parameters were larger in standing with eyes closed and standing after performing 10 turns compared to standing with eyes open on both firm and foam surface. In the ballet dancers all COP velocity parameters were larger in standing with eyes closed compared to all other conditions. The results from the present study indicate that professional ballet dancers do not have a better general balance ability than untrained subjects.
- MeSH
- dospělí MeSH
- funkční lateralita fyziologie MeSH
- lidé MeSH
- mladý dospělý MeSH
- postura těla fyziologie MeSH
- posturální rovnováha fyziologie MeSH
- tanec fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
A wobble board (WB) is a balance rehabilitation tool that is used in physiotherapy to improve strength and stability. The WB tested in this study includes a sensory module for measuring patients' tilt and rotation during stance. The aim of this study was to assess the reliability and validity of a balance measurement using a WB. Thirty healthy young adults participated in this study. The participants stood on the WB to simultaneously record the tilt of the WB and the center of pressure data using a force plate. The data were recorded during five measurement sessions on various days, with four trials each. Sways, velocities and indexes of complexity (CI) were computed. For reliability assessment, we used intra-class correlation coefficients within and between sessions; for validity, we computed Spearman correlation coefficients. The velocities and CI showed good intra-session reliability, and the sways showed mostly poor intra-session reliability. The results of inter-session reliability showed good to excellent reliability for CI, poor reliability for sways and poor to good reliability for velocities. The Spearman correlation coefficient showed excellent agreement between the mean velocities computed from the force plate and the WB. Our results confirm that the WB tested is suitable for stability assessment in young adults.
- MeSH
- entropie * MeSH
- lidé MeSH
- mladý dospělý MeSH
- posturální rovnováha * MeSH
- reprodukovatelnost výsledků MeSH
- Check Tag
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Although entropy-based measurements of gait dynamics are becoming widely used tools for fall risk assessment, their relationship to fall occurrence is still unclear. The aim of this study was hence to compare fallers and non-fallers in terms of gait dynamics assessed by the multiscale and Shannon entropy. This study included 139 participants, aged 60-80 years, divided into two groups according to fall occurrence during a 6-month prospective observation (38 fallers, 101 non-fallers). The methodology involved the use of the Tinetti balance assessment tool (TBAT) and 5min of overground walking with 3D accelerometers located near the L5 vertebra and shanks. We analyzed 150 strides for gait complexity, an index of complexity (CI), computed from multiscale entropy (MSE) and Shannon entropy (ShE) derived from the recurrence quantification analysis. We found no significant differences between groups in MSE and CI. The TBAT total score was significantly higher in non-fallers (P=0.033), however, both groups showed low risk of falls. ShE in the anterior-posterior direction from trunk and in the medial-lateral direction from the shanks were both significantly higher in fallers (P=0.020; P=0.024). ShE was negatively correlated with CI, the shank ShE in the vertical direction was positively correlated with TBAT. Taken together, our findings suggest that MSE is not able to distinguish between highly functional groups, whereas Shannon entropy seems to be sufficient in fall risk prediction.
- MeSH
- chůze (způsob) fyziologie MeSH
- entropie * MeSH
- hodnocení rizik metody MeSH
- lidé středního věku MeSH
- lidé MeSH
- posturální rovnováha fyziologie MeSH
- prospektivní studie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- úrazy pádem prevence a kontrola MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Previous studies reported a significant association between postural control and lower-limb strength of several muscle groups, however, they were focused especially on knee muscles and ankle plantar and dorsal flexors. The aim of the present study is to examine the correlation between the muscle strength of ankle invertors, evertors, plantar flexors, and dorsal flexors and the control of bipedal stance in young and older adults. Thirty one young (aged 22.8 ± 2.6 years) and thirty one older adults (aged 70.5 ± 7.2 years) voluntarily participated in this study. Ankle muscle strength was evaluated by an isokinetic dynamometer. Normalized peak torque and work were averaged for four repetitions and for both lower limbs. The control of bipedal stance was evaluated by the sample entropy derived from an accelerometer placed on the lumbar spine while the subject stood on a foam pad with eyes open. Results showed significant age-related differences in ankle muscle strength and sample entropy in medial-lateral direction. More interestingly, the correlation between ankle muscle strength and the sample entropy was significantly different between young and older adults. Indeed, no significant correlation was observed in the younger adults. Conversely, in the older adults, the work of the ankle evertors positively correlated with sample entropy in the medial-lateral direction during bipedal stance (r = 0.36), whereas the peak torque and work of the dorsal flexors were significantly correlated with sample entropy in the anterior-posterior direction during bipedal stance (r = 0.44 for both variables). In the young adults, results suggest that, standing on foam with eyes open is a relatively easy postural task that does not require the full ankle muscle strength capacity. Taken together, the present findings suggest that older adults have a different association between ankle muscle strength and the sample entropy during bipedal stance.
- MeSH
- kotník fyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- postura těla MeSH
- posturální rovnováha MeSH
- senioři MeSH
- stárnutí * MeSH
- svalová síla * MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In this article, we evaluated the variations of the brain and muscle activations while subjects are exposed to different perturbations to walking and standing balance. Since EEG and EMG signals have complex structures, we utilized the complexity-based analysis. Specifically, we analyzed the fractal dimension and sample entropy of Electroencephalogram (EEG) and Electromyogram (EMG) signals while subjects walked and stood, and received different perturbations in the form of pulling and rotation (via virtual reality). The results showed that the complexity of EEG signals was higher in walking than standing as the result of different perturbations. However, the complexity of EMG signals was higher in standing than walking as the result of different perturbations. Therefore, the alterations in the complexity of EEG and EMG signals are inversely correlated. This analysis could be extended to investigate simultaneous variations of rhythmic patterns of other physiological signals while subjects perform different activities.
- Publikační typ
- časopisecké články MeSH
... Freedom and Constraint 1 -- Chemical Change 4 -- Thermodynamic Functions 6 -- Negative Entropy, Organization ... ... Electrolyte Balance 26 -- Thermodynamics of Electrolyte Balance 27 -- Free Energies of Ion Distribution ... ... Water Balance 35 -- Colligative Properties 36 -- Standard Chemical Potentials and Dielectric Constant ... ... Acid-Base Balance 46 -- Blood Proteins 47 -- Comparative Acid-Base Balance of Red Cells 49 -- Aging Changes ... ... 103 -- Intracellular Water and Negative Entropy 105 -- References -- 108 ...
Interdisciplinary topics in gerontology ; Vol. 8
x, 112 stran : ilustrace, tabulky ; 25 cm
- MeSH
- energetický metabolismus MeSH
- fyzikální chemie MeSH
- fyziologie MeSH
- senioři MeSH
- stárnutí fyziologie MeSH
- Check Tag
- senioři MeSH
- Publikační typ
- monografie MeSH
- Konspekt
- Fyziologie člověka a srovnávací fyziologie
- NLK Obory
- fyziologie
- geriatrie
- chemie, klinická chemie
... Integrals 259 -- Al.7 Geometrical vector theorems 262 -- Appendix 2: The Boltzmann distribution, entropy ... ... and detailed balance 263 -- A2.1 Disorder and the number of available states 263 -- A2.2 The Boltzmann ... ... distribution 265 -- A2.3 Entropy 266 -- A2.4 Detailed balance 266 -- A2.5 An entropic force 268 -- Appendix ...
xii, 286 s.
... - Chemical reactions 14 -- Physical Chemistry -- Energetics 16 -- Equilibriums 18 -- Enthalpy and entropy ... ... Hemoglobin 280 -- Gas transport 282 -- Erythrocyte metabolism 284 -- Iron metabolism 286 -- Acid-base balance ... ... 318 -- Ethanol metabolism 320 -- Kidney -- Functions 322 -- Urine 324 -- Functions in the acid-base balance ...
Basic sciences Flexibook
2nd ed., rev. and enl X, 467 s. : il. ; 18 cm
... Noncovalent Bonds -- 1.3.2 The Properties of Water Affect the Bonding Abilities of Biomolecules -- 1.3.3 Entropy ... ... Formation of Pyruvate 435 -- 16.1.8 Energy Yield in the Conversion of Glucose -- 16.1.9 Maintaining Redox Balance ...
5th ed. xvii, 974 s. : il., tab., grafy ; 32 cm
