Postural Stability in Single-Leg Quiet Stance in Highly Trained Athletes: Sex and Sport Differences

Factors Affecting Balance Performance in Adolescents

(1) Background: The influence of different factors on balance in adolescence is assessed by conducting functional balance tests that examine its different components. (2) Materials and methods: The study sample comprised 110 healthy adolescents of both sexes, aged 12-18 years. Single Leg Stance with Eyes Open (SLS-EO) and Eyes Closed (SLS-EC) tests were conducted to evaluate static balance, whereas the Functional Reach Test (FRT) and Lateral Reach Test (LRT) were performed to establish functional stability limits. The influence of sex, age, demographic factors, anthropometric characteristics, participation in sports activities, and trunk extensor muscle endurance (Biering-Sorensen test) on balance performance was determined through correlational and univariate linear regression analyses. (3) Results: Older age (Beta [β] = 0.247; 95% CI [0.75, 5.20]; p < 0.01) and better trunk extensor muscle endurance (β = 0.224; 95% CI [0.015, 0.13]; p < 0.05) were significant predictors of the SLS-EO results, while younger age (β = -0.219; 95% CI [-1.32, -0.11]; p < 0.05) and higher muscle percentage (β = 0.237; 95% CI [0.06, 0.48]; p < 0.05) emerged as significant predictors of LRT performance, and greater bone mass was a significant predictor of FRT results (β = 0.444; 95% CI [3.62, 8.17]; p < 0.01). However, none of the independent variables was a statistically significant predictor of the SLS-EC results. (4) Conclusions: The current study found that age, trunk extensor muscle endurance, muscle percentage, and bone mass are significant predictors of different balance components, suggesting that balance is task-specific.

Effects of Foot Structure Type on Core Stability in University Athletes

PURPOSE

This study assessed the impact of different types of medial foot arch on postural stability and core center of gravity muscle activity among collegiate athletes.

METHODS

The study sample included 103 university-level athletes across various sports (soccer, rugby, basketball, volleyball, field tennis, table tennis, karate, and cheerleading) from the College of Magdalena (Colombia) who exhibited distinct types of medial foot arch: 32 high, 35 low, and 36 neutral arches. Surface electromyography (sEMG) was employed to assess conduction velocity, magnitude values, latency, and fatigue in focal muscles including the spinal erector (SE), internal oblique (IO), external oblique (EO), and rectus abdominis (AR), while measurements of static and dynamic postural control were also considered. Post hoc analysis was performed with Bonferroni correction for all electromyographically measured muscle groups, as well as for measurements of static and dynamic postural stability. Pearson's or Spearman's correlation tests were used to compare the different types of feet.

RESULTS

There were no substantial differences observed between the distinct types of feet in terms of focal muscle activity, static stability, or dynamics. Even though the mean values indicated higher muscle activity and stability among those with high foot arches and lower values among those with low arches compared to the neutral foot type, this observed difference was deemed statistically insignificant. We also observed a positive correlation between internal oblique muscle activity and the average power of dynamic postural stability, which remained consistent across all foot types. Our findings indicate that static instability is directly correlated with dynamic instability in the anteroposterior direction, while a clear inverse relationship was established in the lateral direction upon examining the variable correlations.

CONCLUSIONS

The presence of high or low foot arches did not significantly impact the activity of the muscles responsible for maintaining the body's center of gravity or postural stability among university-level athletes. This suggests the existence of neuromuscular compensation mechanisms that attempt to restore balance and compensate for any changes in postural stability caused by varying foot types. Through targeted training that emphasizes activation of the internal oblique muscle, athletes may see improved postural stability. Our findings indicate that static stabilization exercises can also prove beneficial in improving dynamic stability in the anteroposterior plane, while a more dynamic approach may be required to improve dynamic stability in the lateral plane.

The optimal method for improving postural balance in healthy young and older people: specific training for postural tasks encountered in personal physical practice

It is well known that regular exercise or physical activity (training) improves postural balance in healthy young and older subjects, but the optimal exercise or physical activity (i.e., likely to induce the greatest postural improvements) and the context in which it is carried out remain to be explored and determined for each population. The most beneficial adaptations would depend, in particular, on gestural conditions (body position, movement and gesture practiced) and material conditions (nature of the ground surface, sports equipment used, type of environment - stable or changing). In fact, the global postural adaptations induced by training do not result from the transfer between different trained and untrained postural tasks, but are the sum of the adaptations related to each trained postural task in healthy young and older subjects. Based on current knowledge, optimal training programs should include the full range of postural tasks encountered in personal physical practice for each population. To date, the method of implementing progressive postural balance tasks with different degrees of difficulty and instability has been used as the effective method to improve postural balance, but it should not be considered as the reference method. Instead, it should be considered as a complementary method to the one based on specific postural tasks. An intervention strategy is proposed for young and older adults consisting of three different steps (general, oriented and specific/ecologic training). However, some parameters still need to be explored and possibly reconsidered in future studies to improve postural balance in an optimal way.

Static Postural Control during Single-Leg Stance in Endurance, Team and Combat Athletes from the Spanish National Sport Technification Program

In the context of pediatric physical exercise, the analysis of factors affecting postural control (PC) provides insight into the development of sport-specific motor skills. This study aims to evaluate the static PC during single-leg stance in endurance, team and combat athletes from the Spanish National Sport Technification Program. A total of 29 boys and 32 girls, aged 12 to 16 years old, were recruited. Centre of pressure (CoP) was measured on a force platform in standing position for 40 s under two sensorial and leg dominance conditions. Girls showed lower MVeloc (p < 0.001), MFreq (p > 0.001) and Sway (p < 0.001) values than boys in both sensorial conditions (open and closed eyes). The highest values in all PC variables were observed with eyes closed in both genders (p < 0.001). Sway values were lower in boys combat-athletes compared to endurance athletes in two sensorial conditions and with non-dominant leg (p < 0.05). Young athletes in their teens enrolled in a Sport Technification Program have shown differences in PC when comparing different visual conditions, sport disciplines and gender. This study opens a window to a better understanding of the determinants of PC during single-leg stance as a critical element in the sport specialization of young athletes.

Validity and Reliability of Kinvent Plates for Assessing Single Leg Static and Dynamic Balance in the Field

The objective of this study was to validate PLATES for assessing unipodal balance in the field, for example, to monitor ankle instabilities in athletes or patients. PLATES is a pair of lightweight, connected force platforms that measure only vertical forces. In 14 healthy women, we measured ground reaction forces during Single Leg Balance and Single Leg Landing tests, first under laboratory conditions (with PLATES and with a 6-DOF reference force platform), then during a second test session in the field (with PLATES). We found that for these simple unipodal balance tests, PLATES was reliable in the laboratory and in the field: PLATES gives results comparable with those of a reference force platform with 6-DOF for the key variables in the tests (i.e., Mean Velocity of the Center of Pressure and Time to Stabilization). We conclude that health professionals, physical trainers, and researchers can use PLATES to conduct Single Leg Balance and Single Leg Landing tests in the laboratory and in the field.

Is There Influence of Gender and the Specificity of Sports Activities on the Performance of Body Balance in Young Athletes?

Sports training can significantly influence specific motor skills. The aim of this study was to investigate the influence of gender and the specificity of sports activities on body balance, symmetry of lower extremity loads (SI) as well as body mass index (BMI) in young athletes aged 14 to 17. There were 240 participants (145 boys and 95 girls) divided into five groups: swimmers, dancers, soccer players, archery and control group. The average age was 16. Participants had 3 years of training experience (training three times a week or training that lasted between 4.5 and 6 h weekly). To assess balance, the stabilized Zebris platform was used in the study. The SI was calculated based on the percentage load on the lower extremities, dividing the greater value by the lower. Body mass index was calculated on the basis of height and weight. Women had a significantly lower BMI and balance in some analyzed parameters, while men had better SI. Archers obtained the best results of the balance parameters and the worst results of SI. Only swimmers and soccer players had a normal SI. Sports specialization generates significant differences in the manifestation of balance compared to the gender variable and sport discipline.

Differences in the manifestation of balance according to BMI levels for women students of the Faculty of Physical Education and Sports

Abstract Background: Static and dynamic balance are factors of major importance in the manifestation of human motor skills at a higher level. Purpose: The determination of vari-ations in the performance of balance tests for young women students at the Faculty of Physical Education and Sports (48 cases in the 1st year of bachelor's degree), divided and analyzed 3 BMI levels (underweight / 7 cases, normal weight / 34 cases and overweight / 7 cases) and comparing these results with other similar research. Material and method: The testing of the group was scheduled at the Research Center for Human Performance, be-longing to the Faculty of Physical Education and Sports in Galați, in the month of April of the 2018-2019 academic year. For the assessment of balance, 7 tests were used, of which 4 associated with dynamic postural stability (Walk and turn field sobriety test/errors, Func-tional reach test/cm, Fukuda test/degrees of rotation, Bass test/ points) and 3 measuring static stability (Flamingo test/falls, One leg standing with eyes closed/sec, Stork test/sec). Nonparametric tests (Mann-Whitney U) were applied to compare differences between batches. Results: The average values of underweight and normal-weight women are better than those of overweight women for the entire set of assessment tests. The underweight group has the best results for the Standing balance test, Functional reach test, Flamingo test, Walk and turn field sobriety test, Fukuda test, and the normal weight women for Stork test, respectively Bass test. We found a lack of significant thresholds when comparing the results between the 3 groups (P> 0.05) for Stork test, Standing balance test and Functional reach test, so the working hypothesis formulated is only partially confirmed. The only significant difference between underweight and normal weight (P <0.05) is found in the Flamingo test, with better values for underweight. Significant difference thresholds for Flamingo test and Fukuda test are recorded between the underweight and overweight groups (Z values have associated thresholds P<0.05). The most significant differences are found between the normal weight and overweight groups (P <0.05), respectively for the Bass test, Fukuda test and Walk and turn field sobriety test. Conclusion: Constant physical activity (as a feature of the analyzed group) reduces the chances of significant differences in all balance tests between BMI levels. Keywords: female students; university specialization; static and dynamic postural control; physical activity

The Influence of Gender and the Specificity of Sports Activities on the Performance of Body Balance for Students of the Faculty of Physical Education and Sports

A sense of balance is required in sports activities, conditioning the quality of movements and physical performance. (1) The purpose of the study is to investigate the influence of gender and the specificity of sports activities on body balance. The investigated participants are 157 students of the Faculty of Physical Education and Sports/Bachelor’s degree: 109 men (age = 20.49 ± 2.03, body mass index, BMI = 22.96 ± 3.20), and 48 women (age = 20.21 ± 1.51, BMI = 21.05 ± 2.78). (2) Design: Cross-sectional study, with the definition of the variables gender and sport activity with three stages (non-athletes/NA, team sports games/TSG, and individual sports/IS). The evaluation was based on four dynamic balance tests (Bass test/points, Functional reach test/cm, Fukuda test/degrees of rotation, and Walk and turn field sobriety test/errors) and three static balance tests (Flamingo test/falls, Stork test, and One-leg standing test with eyes closed/s). (3) Results: The variance analysis (multivariate and univariate tests) indicates the superiority of women in most tests applied, but with significantly better values (p < 0.05) only for the Flamingo test and Bass test. Men have superior results only for vestibular stability (Fukuda test) and One-leg standing test, but it is statistically insignificant (p > 0.05). The TSG group has slightly better values than the IS group for the whole set of tests conducted, but these are not statistically significant (p > 0.05), so we cannot highlight the certain superiority of TSG practitioners over those involved in IS. Both the TSG and the IS group outperformed all tests compared to the NA group, with significant differences (p < 0.05), especially for the TSG. Conclusion: Women have better values than men on most tests, and performance sports students have higher average scores than those in the NA group, which demonstrates the beneficial influence of specific training on static and dynamic postural stability.