Showing 3 results for Variability
Khadijeh Ahrari, Mandana Gholami, Maryam Chamani, Hossein Abednatanzi,
Volume 22, Issue 6 (1-2020)
Abstract
Background and Aim: Pregnancy and exercise training are associated with changes in the cardiovascular anatomy and physiology. There is a few studies on this issue in Iran. In this regard, the aim of this study is to assess the effect of a combined exercise training program on blood pressure and heart rate variability of pregnant women.
Methods & Materials: This randomized clinical trial was conducted in Shahid Akbarabadi Hospital in Tehran, Iran in 2019. Participants were 10 healthy pregnant women with a gestational age of 24-26 weeks in the interventional group and 10 healthy pregnant women in the control group. The interventional group received 8 weeks of combined exercise training at moderate intensity. The blood pressure measurement, electrocardiogram and aerobic and resistant exercise tests of samples were performed before and after training. AST3000 Avicenna software was used to analyze the heart rate variability parameters, and for statistical analysis, paired and independent t-tests, Mann Whitney U, and Wilcoxon tests were used.
Ethical Considerations: This study with registered clinical trial code IRCT20190227042856N1 was approved by the Research Ethics Committee of Islamic Azad University of Science and Research Branch in Tehran, Iran (code: IR.IAU.SRB.REC.1397.101).
Results: The mean systolic and diastolic blood pressure levels were lower in the interventional group by the 34th week of pregnancy compared to the control group (P<0.05). The mean of time-domain parameters in the interventional group were higher by the 34th week of pregnancy compared to the control group (P<0.05).
Conclusion: Combined exercise training can improve autonomic and parasympathetic nervous systems in pregnant women.
Dr Banafsheh Ghaheri, Dr Shahzad Tahmasebi Boroujeni, Dr Mehdi Shahbazi, Dr Ahmad Reza Arshi,
Volume 24, Issue 6 (1-2022)
Abstract
Background and Aim: Evaluating variability can help to investigate the process underlying motor coordination problems. The current study aimed to measure motor coordination and its variability in children with Developmental Coordination Disorder (DCD). Moreover, the symmetry of motor coordination variability in these children and the relation between motor skills and variability were explored.
Materials and Methods: After evaluating motor skills in children, aged 7-10 years using Movement Assessment Battery for Children-2 (MABC-2), 15 children with DCD and 20 non-DCD children performed a bilateral coordination task. Using motion capture system, motor coordination and variability were recorded and calculated by computing continuous relative phase and its standard deviation, respectively.
Ethical Considerations: The study with an ethical code of IR.UT.SPORT.REC.1396030 was approved by Ethics Committee of Faculty of Physical Education and Sport Sciences of University of Tehran.
Findings: Children with DCD showed significantly higher variability, while there was no significant difference between the groups in performing the coordination task. Moreover, the variability of motor coordination was found asymmetrical in children with DCD. Finally, more variability was shown to be accompanied with lower score in motor skills of the participants.
Conclusion: The current study shows the necessity of employing assessments related to underlying process of movement coordination such as variability, which can help to provide more comprehensive understanding of motor patterns of children with DCD and the strategies that they adopt to execute and produce movement.
Saeed Pazhoohan, Fatemeh Abbasi Feijani, Abdollatif Moini , ,
Volume 26, Issue 6 (2-2024)
Abstract
Chronic obstructive pulmonary disease (COPD) is a progressive and debilitating condition. People with COPD often experience exacerbations that may require hospitalization. Pattern analysis of respiratory variability can provide valuable insights into the complexity of the respiratory control system. Therefore, this study investigated respiratory pattern variability during stable and exacerbation phases in patients with COPD.
We analyzed respiratory signal data from 14 patients with COPD during exacerbations and stable phases and compared them with 12 age- and sex-matched control subjects. Respiratory pattern variability analysis of 30-minute inter-breath intervals (IBI) time series was performed using sample entropy and Detrended Fluctuation Analysis.
Sample entropy analysis of the IBI revealed that respiratory variability was more regular during both stable and exacerbation phases in patients with COPD. Also, the short-term (α1) and long-term fractal-like correlation (α2) significantly decreased during both exacerbation and stable phases compared to healthy controls.
The respiratory control system in patients with COPD shows less variability (lower entropy and fractal correlation). This reduction in respiratory signal variability indices in COPD patients is still lower than in healthy people, even when their disease status is stabilized.
