The relationships between knee extensors/ flexors strength and balance control in elite male soccer players

Background Strength and balance are important factors for soccer players to be successful. This study’s aim was to determine the relationship between lower-limb muscle strength and balance control in elite male soccer players (n = 77). Methods Concentric isokinetic strength (peak torque of quadriceps (PT-Q) and hamstrings (PT-H), hamstrings/quadriceps (H/Q) ratio) was measured for the dominant and non-dominant leg at angular velocities of 60°s−1and 240°s−1, as well as the total work for extensors (TW-Q) and flexors (TW-H) for both legs (at an angular velocity of 240°s−1only). Balance score (BAL score) was used for unilateral assessment of balance control using a Delos Postural System Test measurement tool. Hierarchical multiple regression analyses were performed to predict balance control using isokinetic knee strength performance for dominant and non-dominant legs. Results Final modelling included peak torque of hamstrings at 240°s−1 and peak torque of the quadriceps at 240°s−1 for the non-dominant leg (R2 = 19.6%; p ≤ 0.001) and only peak hamstring torque at 240°s−1 for the dominant leg (R2 = 11.3%; p = 0.003) as significant predictors of balance score. Conclusion Findings indicate that balance control is widely influenced by peak hamstring torque and peak quadriceps torque at high angular velocity particularly in the non-dominant leg i.e., the supporting leg in soccer players.

Visual Effect on Brain Connectome That Scales Feedforward and Feedback Processes of Aged Postural System During Unstable Stance

Older adults with degenerative declines in sensory systems depend strongly on visual input for postural control. By connecting advanced neural imaging and a postural control model, this study investigated the visual effect on the brain functional network that regulates feedback and feedforward processes of the postural system in older adults under somatosensory perturbations. Thirty-six older adults conducted bilateral stance on a foam surface in the eyes-open (EO) and eyes-closed (EC) conditions while their center of pressure (COP) and scalp EEG were recorded. The stochastic COP trajectory was modeled with non-linear stabilogram diffusion analysis (SDA) to characterize shifts in postural control in a continuum of feedback and feedforward processes. The EEG network was analyzed with the phase-lag index (PLI) and minimum spanning tree (MST). The results indicated that visual input rebalanced feedforward and feedback processes for postural sway, resulting in a greater critical point of displacement (CD), short-term effective diffusion coefficients (Ds) and short-term exponent (Hs), but the smaller critical point of time (CT) and long-term exponent (Hl) for the EC state. The EC network demonstrated stronger frontoparietal-occipital connectivity but weaker fronto-tempo-motor connectivity of the theta (4–7 Hz), alpha (8–12 Hz), and beta (13–35 Hz) bands than did the EO network. MST analysis revealed generally greater leaf fraction and maximal betweenness centrality (BCmax) and kappa of the EC network, as compared with those of the EO network. In contrast, the EC network exhibited a smaller diameter and average eccentricity than those of the EO network. The modulation of long-term negative feedback gain of the aged postural system with visual occlusion was positively correlated with leaf fraction, BCmax, and kappa, but negatively correlated with the diameter and average eccentricity for all EEG sub-bands. In conclusion, the aged brain functional network in older adults is tuned to visual information for modulating long-term negative feedback of the postural system under somatosensory perturbations.

The Influence of Biofeedback in Postural Rehabilitation of Athletes

"ABSTRACT. Background. A balanced posture allows sports movements PERFORMANCE with optimal consumption of energy and minimal stress on the musculoskeletal system with of the technology offered by the posturograph, we can identify the center of gravity deviations, the points of support, the load, the weight distribution in the soles, the anterior posteriorized or compressed posture, the asymmetries of the body. by an interpretation in biomechanical context, any compensations or decompensations can be identified. Aim. The aim of the study is to improve posture through biofeedback treatment using the GPS 600 device. Materials. The Posturograph or Global Postural System (GPS) is an advanced postural analysis system that uses techniques and methods of noninvasive diagnosis and evaluation in the field of medical recovery. Posturography includes 2 diagnostic units and software. Methods. We used the following methods: bibliographic study methods, method of observation, measurement method, experimental method, statistical method. Applied treatments. The treatments for re-educating the posture with the GPS 600 device took place for 2 weeks. During the treatment, the subjects had to maintain their body position / posture as indicated by the device. Results. From the 12 athletes, the anteriority of the head improved, the center of gravity, loading on the right and left lower limbs. At the end of the 2 weeks, the athletes reached a perfect balance of the center of gravity and the weight distribution on the lower limbs. Conclusion. Biofeedback treatments with the GPS 600 device help to improve POSTURE and maintain the results over time."

The Effectiveness of Postural Biofeedback in the Physical Therapy of Patients With Cervical Spondylosis

"ABSTRACT. Background. The influence of biofeedback treatment with the help of the Global Postural System GPS 600 device combined with a physiotherapy program for the cervical spine proved to be beneficial. The presence of headaches and the sensitivity of the cervical spine given by arthrosis, require that the movements at this level must be done very carefully. Aim. The aim of this study is to prove the importance and benefits of biofeedback treatment using the Global Postural System GPS 600 combined with a physical therapy program in degenerative diseases of the cervical spine for adults involved in work activities that require maintaining a sitting position at the office Subjects. This study included 30 patients with the age between 28 to 59 years old, the mean age was 38 years. Methods. The methods used for evaluation were joint and muscle balance as well as the visual analogue scale of pain, and the evaluation data provided by the GPS 600 system. Results. At the end of the 14 days of biofeedback treatment and physical therapy program, all patients had a relief of symptoms and the alignment of the spine was significantly corrected. Conclusion. Biofeedback treatment using the Global Postural System GPS 600 combined with physical therapy is important in the recovery of degenerative diseases of the cervical spine both for the effect on the joints and for the general effect of postural balance."

The association between pelvic asymmetry and non-specific chronic low back pain as assessed by the Global Postural System.

Background: Empirical evidence that demonstrates the relationship between pelvic asymmetry and non-specific chronic low back pain (NCLBP) is currently lacking. Objective: To establish the reliability of the Global Postural System (GPS) in assessing pelvic asymmetry and identify the association between pelvic asymmetry parameters and the occurrence of NCLBP in young adults.Design: A cross-sectional, regression study. Methods: People who were aged between 18 and 30 and were diagnosed with NCLBP were recruited. Healthy individuals who were matched for age, sex, and education level were recruited as controls. Global Postural System (GPS) was employed to assess pelvic asymmetry. Prior to exploring the association, the reliability of GPS was assessed by the ICC (2, k) for interrater reliability, ICC (3, k) for intra-rater reliability, standard error and minimal detectable difference. Bivariate correlation analysis and logistic regression analysis were used to determine the relationship between pelvic asymmetry and the occurrence of NCLBP.Results: Twenty-eight healthy participants and 28 people with NCLBP were recruited. Moderate to excellent ICCs were observed for the inter-rater and intra-rater reliability of most postural parameters. The bivariate correlation analysis indicated that age, body mass index and pelvic asymmetry parameters were related to the occurrence of NCLBP. Pelvic angle asymmetry (odds ratio=1.17), and asymmetry of the distance between the posterior superior iliac spine and the floor (odds ratio=1.21) were associated with NCLBP.Limitation: This study did not explore the causal relationship between pelvic asymmetry in the sagittal plane/pelvic asymmetry in the transverse plane and the occurrence of NCLBP. The interpretation of the results may not be generalized beyond the sample population.Conclusions: The GPS is a reliable method to assess pelvic asymmetry in a clinical setting. Two pelvic parameters were associated with the presence of NLBP. Measurement of pelvic asymmetry may assist in the early identification of potential occurrence of NCLBP but further work is required.

The association between pelvic asymmetry and non-specific chronic low back pain as assessed by the Global Postural System.

Background: Empirical evidence that demonstrates the relationship between pelvic asymmetry and non-specific chronic low back pain (NCLBP) is currently lacking.Objective: To establish the reliability of the Global Postural System (GPS) in assessing pelvic asymmetry and identify the association between pelvic asymmetry parameters and the occurrence of NCLBP in young adults.Design: A cross-sectional, regression study.Methods: People who were aged between 18 and 30 and were diagnosed with NCLBP were recruited. Healthy individuals who were matched for age, sex, and education level were recruited as controls. Global Postural System (GPS) was employed to assess pelvic asymmetry. Prior to exploring the association, the reliability of GPS was assessed by the ICC (2, k) for interrater reliability, ICC (3, k) for intra-rater reliability, standard error and minimal detectable difference. Bivariate correlation analysis and logistic regression analysis were used to determine the relationship between pelvic asymmetry and the occurrence of NCLBP.Results: Twenty-eight healthy participants and 28 people with NCLBP were recruited. Moderate to excellent ICCs were observed for the inter-rater and intra-rater reliability of most postural parameters. The bivariate correlation analysis indicated that age, body mass index and pelvic asymmetry parameters were related to the occurrence of NCLBP. Pelvic angle asymmetry (odds ratio=1.17), and asymmetry of the distance between the posterior superior iliac spine and the floor (odds ratio=1.21) were associated with NCLBP.Limitation: This study did not explore the causal relationship between pelvic asymmetry in the sagittal plane/pelvic asymmetry in the transverse plane and the occurrence of NCLBP. The interpretation of the results may not be generalized beyond the sample population.Conclusions: The GPS is a reliable method to assess pelvic asymmetry in a clinical setting. Two pelvic parameters were associated with the presence of NLBP. Measurement of pelvic asymmetry may assist in the early identification of potential occurrence of NCLBP but further work is required.

Postural Dysfuctions and Strabismus: Correlations

Purpose: Patient with strabismus may assume a compensatory posture. Posturology treats patients with abnormal head position through the stimulation of foot, ocular and stomatognathic receptors. As an alternation of one or more receptor occurs, the tonic postural system seeks to carer for this problems by adopting compensatory postures (scoliosis, abnormalities of distribution of the podalic load, abnormal head position). The extrinsic eye muscles, the head, neck and tongue muscles arise from the occipital somites: probably this explains the relationship between the ocular misalignment and abnormal posture. The objective of this work is to evaluate the relationships between oculomotor e postural defects. Methods: N = 47 patients received a comprehensive ophthalmologic and orthoptic examination. They underwent baropodometric and stabilometric examinations. Results: Our sample group included 37 patients with exodeviation, 17 patients with esodeviation. We observed: flat foot with an incidence rate of 83.33% (25 out of 33) in exotropic subjects; pes cavus with an incidence rate of 16.66% (5 out of 30) in exotropic subjects; flat foot with an incidence rate of 23.52% (4 out of 17) in esotropic subjects; pes cavus with an incidence rate of 76.47% (13 out of 17) in esotropic subjects. Clinical physiatry observation of patients with Eso/Exo deviations prove a considerable turn-out of postural disorders: lumbar scoliosis (76.47%). Conclusions: In our sample, patients with exodeviation have flat feet (83.33%); the subjects with esodeviation have pes cavus (76.47%). However, there is a widely recognized need for a further extensive study and evaluation of the results obtained regarding binocular vision and posture.

The association between pelvic asymmetry and non-specific chronic low back pain as assessed by the Global Postural System.

Background: Empirical evidence that demonstrates the relationship between pelvic asymmetry and non-specific chronic low back pain (NCLBP) is currently lacking. Objective: To establish the reliability of the Global Postural System (GPS) in assessing pelvic asymmetry and identify the association between pelvic asymmetry parameters and the occurrence of NCLBP in young adults. Design: A cross-sectional, regression study. Methods: People who aged between 18 and 30 and were diagnosed with NCLBP were recruited. Healthy individuals who were matched for age, gender, and education level were recruited as controls. Global Postural System (GPS) was employed to assess pelvic asymmetry. Prior to explore the association, the reliability of GPS was assessed by the ICC (2, k) for interrater reliability, ICC (3, k) for intra-rater reliability, standard error and minimal detectable difference. Bivariate correlation analysis and logistic regression analysis were used to determine the relationship between pelvic asymmetry and the occurrence of NCLBP. Results: Twenty-eight healthy participants and 28 people with NCLBP were recruited. Moderate to excellent ICCs were observed for the inter-rater and intra-rater reliability of most postural parameters. The bivariate correlation analysis indicated that age, body mass index and pelvic asymmetry parameters were related to the occurrence of NCLBP. Pelvic angle asymmetry (odd ratio=1.17), and asymmetry of the distance between the posterior superior iliac spine and the floor (odd ratio=1.21) were significant factors associated with NCLBP. Limitation: This study did not explore the causal relationship between pelvic asymmetry in the sagittal plane/pelvic asymmetry in the transverse plane and the occurrence of NCLBP. The interpretation of the results may not be generalized beyond the sample population. Conclusions: The GPS is a reliable method to assess pelvic asymmetry in a clinical setting. The pelvic asymmetry parameters obtained from the GPS are likely to assist in the early identification of the potential occurrence of NCLBP.

Multifractal roots of suprapostural dexterity

Visually guided postural control emerges in response to task constraints. Task constraints generate physiological fluctuations that foster the exploration of available sensory information at many scales. Temporally correlated fluctuations quantified using fractal and multifractal metrics have been shown to carry perceptual information across the body. The risk of temporally correlated fluctuations is that stable sway appears to depend on a healthy balance of standard deviation (SD): too much or too little SD entails destabilization of posture. This study presses on the visual guidance of posture by prompting participants to quietly stand and fixate at distances within, less than, and beyond comfortable viewing distance. Manipulations of the visual precision demands associated with fixating nearer and farther than comfortable viewing distance reveals an adaptive relationship between SD and temporal correlations in postural fluctuations. Changing the viewing distance of the fixation target shows that increases in temporal correlations and SD predict subsequent reductions in each other. These findings indicate that the balance of SD within stable bounds may depend on a tendency for temporal correlations to self-correct across time. Notably, these relationships became stronger with greater distance from the most comfortable viewing and reaching distance, suggesting that this self-correcting relationship allows the visual layout to press the postural system into a poise for engaging with objects and events. Incorporating multifractal analysis showed that all effects attributable to monofractal evidence were better attributed to multifractal evidence of nonlinear interactions across scales. These results offer a glimpse of how current nonlinear dynamical models of self-correction may play out in biological goal-oriented behavior. We interpret these findings as part of the growing evidence that multifractal nonlinearity is a modeling strategy that resonates strongly with ecological-psychological approaches to perception and action.