Acute Impact of Proprioceptive Exercise on Proprioception and Balance in Athletes

This study aimed to compare the acute effect of a proprioceptive exercise session and a non-specific exercise session on knee position sense, and the static and dynamic balance of athletes. Sixty male athletes (19.4 ± 1.2 years) participated in a within-subjects repeated-measures study. Knee position sense in closed kinetic chain, and static (BESS test) and dynamic balance (Y-balance test) were measured before and after two exercise sessions, consisting of 10 min of non-specific exercise in a cycle-ergometer or proprioceptive exercise with an unstable platform. Overall, both exercise sessions significantly improved knee position sense, BESS score, and YBT composite score, and no differences were detected between proprioceptive and non-specific sessions (knee position sense, −6.9 ± 65.2% vs. −11.5 ± 75.0%, p = 0.680; BESS, −19.3 ± 47.7% vs. −29.03 ± 23.5%, p = 0.121; YBT, 2.6 ± 2.7% vs. 2.2 ± 2.2%, p = 0.305). Twenty athletes did not improve knee position sense after the exercise session (non-responders). When analyzing only the exercise responders, both sessions improved knee position sense, but the improvement was greater after the proprioceptive exercise session (56.4 ± 25.6% vs. 43.8 ± 18.9%, p = 0.023). In conclusion, a single proprioceptive, as well as non-specific, exercise session increased knee position sense and balance. The proprioceptive exercise seems to be more effective in improving joint position sense when considering only athletes who respond to the intervention.

Medium-term Results of Body Balance Trainings in Primary School-Aged Children with Generalized Joint Hypermobility and Symptomatic Mobile Flat Foot: Cohort Study

Background. Mobile flat foot etiology and its correlations with postural imbalance remain topical issues for now, especially in children with generalized joint hypermobility. Additionally, it is poorly known that complaints prevail in children with mobile flat foot and joint hypermobility, and whether existing complaints are associated with foot deformation.Objective. The aim of the study is to estimate medium-term effects of body balance trainings on the height of longitudinal arch of the foot and on the complaints structure in primary school-aged children with generalized joint hypermobility.Methods. The study included 114 primary school-aged children (7–11 years old) with mobile symptomatic flat foot who were divided into four groups: I — control group of children who did not perform training; II — children who performed standard complex of rehabilitation exercises recommended for flat foot; III — children who performed a specially designed complex of exercises for body balance training; IV — children exercised on unstable platform. The foot examination included: clinical assessment of feet shape and position (FPI-6 scale), visual and manual mobility tests, computer scanning with calculation of anthropometric indices (basic anthropometric parameters were calculated from scanned foot images). Clinical evaluation of balance was carried out according to the BESS (Balance Error Scoring System) scale and computer pedobarometry. Assessment of complaints structure was carried out according to the Oxford Child Foot Condition Questionnaire.Results. Children of control group significantly increased the number of errors in performing tests compared to the baseline data (p = 0.034) according to the BESS scale. No statistically significant changes were obtained in children of the second group (p = 0.08). Total number of errors committed by children of third and fourth groups on unstable platform decreased by 2.9 times and 3.4 times, respectively (p = 0.022 and p = 0.044). Decrease in partial load on medial longitudinal arch of foot in step cycle in average by 2.0–3.5 times compared to baseline parameters was revealed in children of third and fourth groups. Moreover, children of third and fourth groups have shown improvement in parameters regarding the shape and position of the feet by average of 1.3–1.7 times higher compared to the parameters of the feet of children performing standard complex of rehabilitation exercises (p = 0.036).Conclusion. This study has shown the efficacy of body balance training in increasing the height of longitudinal arch of the foot and good dynamics in the structure of complaints in primary school-aged children with generalized joint hypermobility and symptomatic mobile flat foot.

The effectiveness of mechanotherapeutic methods for spine deep stabilization system training in patients with osteoporotic vertebral fractures

The aim of the study was to estimate the effect of new physical rehabilitation complex using of mechanotherapeutic methods on spine muscle strength in patients with osteoporosis (OP) and vertebral fractures (VF). Material and methods: Study comprised of 90 osteoporotic patients aged 50-80 years old (65.4±9.1 years) with OP VFs who were randomized as 2:1 into intervention group (group1, n=60) and control group (group2, n=30). Patients in group 1 received an intensive rehabilitation course including back muscle training with mechanical loads #10; sensorimotor training on double unstable platform #10; kinesohydrotherapy in a pool #15; physical exercises in a gym #10. Group 2 was prescribed only physical exercises in a gym #15. All patients undergo tenzodynamometry on BackCheck diagnostic unit (Dr. Wolff, Germany) at baseline, in 3 weeks at the end of rehabilitation course and in a month of follow-up. Results: In group 1 after the rehabilitation course muscle strength improved in trunk extensors (TE) from 15.8±10.1 to 21.7±13.1 kg (p<0.001), trunk flexors (TF) from 14.5±9.1 to 18.9±10.2 kg (p<0.001), left lateral flexors (LLF) from 12.8±7.2 to 17.5±9.6kg (p<0.001) and right lateral flexors (RLF) from 13.2 ± 7.1 to 17.8 ± 9.2 kg (p<0.01). Strength deficiency significantly decreased in all muscles (p<0.001 for TE and TF, p<0.05 for LLF, p<0.01 for RLF). The achieved effect lasted for a month of follow-up. In group 2 positive dynamics of strength was observed after 3 weeks only in TE and TF (p<0.05), however, after a month of observation, the strength of all the studied muscles did not differ from the baseline (p>0.05). Conclusion: The new 3-week complex of physical rehabilitation using of mechanotherapeutic methods lead to increase of spine muscle strength and improvement of muscle strength deficiency in patients with osteoporotic VFs. Rehabilitation effect lasts for at least a month after the treatment completion.

Distinguishing Two Types of Variability in a Sit-to-Stand Task

Variability is commonly observed in complex behavior, such as the maintenance of upright posture. The current study examines the value added by using nonlinear measures of variability to identify dynamic stability instead of linear measures that reflect average fluctuations about a mean state. The largest Lyapunov exponent (λ1) and SD were calculated on mediolateral movement as participants performed a sit-to-stand task on a stable and unstable platform. Both measures identified changes in movement across postures, but results diverged when participants stood on the unstable platform. Large SD indicated an increase in movement variability, but small λ1 identified those movements as stable and controlled. The results suggest that a combination of linear and nonlinear analyses is useful in identifying the proportion of observed variability that may be attributed to structured, controlled sources. Nonlinear measures of variability, like λ1, can further be used to make predictions about transitions between stable postures and to identify a system’s resistance to disruption from external perturbations. Those features make nonlinear analyses highly applicable to both human movement research and clinical practice.

Microwave Staring Correlated Imaging Based on Unsteady Aerostat Platform

Microwave staring correlated imaging (MSCI), with the technical capability of high- resolution imaging on relatively stationary targets, is a promising approach for remote sensing. For the purpose of continuous observation of a fixed key area, a tethered floating aerostat is often used as the carrying platform for MSCI radar system; however, its non-cooperative random motion of the platform caused by winds and its unbalance will result in blurred imaging, and even in imaging failure. This paper presents a method that takes into account the instabilities of the platform, combined with an adaptive variable suspension (AVS) and a position and orientation system (POS), which can automatically control the antenna beam orientation to the target area and measure dynamically the position and attitude of the stochastic radiation radar array, respectively. By analyzing the motion feature of aerostat platform, the motion model of the radar array is established, then its real-time position vector and attitude angles of each antenna can be represented; meanwhile the selection matrix of beam coverage is introduced to indicate the dynamic illumination of the radar antenna beam in the overall imaging area. Due to the low-speed discrete POS data, a curve-fitting algorithm can be used to estimate its accurate position vector and attitude of each antenna at each high-speed sampling time during the imaging period. Finally, the MSCI model based on the unsteady aerostat platform is set up. In the simulations, the proposed scheme is validated such that under the influence of different unstable platform movements, a better imaging performance can be achieved compared with the conventional MSCI method.

Evaluation of postural stability in children depending on the body mass index

Introduction: Obesity is a common health issue among children and adolescents leading to serious consequences later in life. There are reports on postural stability in children in relation to their nutritional status, but there are few studies involving a stabilometric platform. Aim: A comparison of postural stability in children with normal body mass and obese children. Material and methods: The stabilometric study involved 166 subjects. The postural stability evaluation was performed with the use of the Biodex Balance System platform. The following four postural stability tests were carried out: (1) eyes open, stable platform (SI0); (2) eyes open, level 4 unstable platform (SI4); (3) eyes open, level 4 unstable platform with the screen covered (SI4SC); (4) eyes closed, level 4 unstable platform (SI4EC), and the fall risk test (FRT). Results and Discussion: There were statistically significant differences found in the SI4, SI4SC, SI4EC, and FRT tests in all the inspected parameters. Only in the postural stability test on a stable platform (SI0) no differences were noted. The most marked differences between arithmetic means obtained for both groups were observed in the postural stability test on an unstable platform with closed eyes. Conclusions: Children with obesity are characterised by increased instability on a moving surface compared to children of normal body mass. Obese children experience the biggest problem when regaining balance with their eyes closed. It is advisable to include training on an unstable surface in physiotherapy programmes for obese children.