Evaluation of the isokinetic muscle function, postural control and plantar pressure distribution in capoeira players: a cross-sectional study

Do visual and step height factors cause imbalance during bipedal and unipedal stances? A plantar pressure perspective

Objective: The plantar pressure analysis technique was used to explore the static balance ability and stability of healthy adult males under the influence of visual and step height factors during bipedal and unipedal stances. Methods: Thirty healthy adult males volunteered for the study. Experiments used the F-scan plantar pressure analysis insoles to carry out with eyes open (EO) and eyes closed (EC) at four different step heights. The plantar pressure data were recorded for 10 s and pre-processed to derive kinematic and dynamic parameters. Results: For unipedal stance, most of kinematic parameters of the subjects' right and left feet were significantly greater when the eyes were closed compared to the EO condition and increased with step height. The differences in toe load between right and left feet, open and closed eyes were extremely statistically significant (p < 0.001). The differences in midfoot load between the EO and EC conditions were statistically significant (p = 0.024) and extremely statistically significant between the right and left feet (p < 0.001). The difference in rearfoot load between EO and EC conditions was extremely statistically significant (p < 0.001) and statistically significant (p = 0.002) between the right and left feet. For bipedal stance, most of kinematic parameters of the subjects' EO and EC conditions were statistically significant between the right and left feet and increased with step height. The overall load's difference between EO and EC states was statistically significant (p = 0.003) for both feet. The overall load's difference between the right and left feet was extremely statistically significant (p < 0.001) in the EC state. The differences between the right and left feet of the forefoot and rearfoot load with EO and EC suggested that the right foot had a smaller forefoot load, but a larger rearfoot load than the left foot (p < 0.001). The differences between the forefoot and rearfoot load of the subjects' both feet with EO and EC were extremely statistically significant (p < 0.001). Conclusion: Both visual input and step height factors, even the dominant foot, act on kinematic and dynamic parameters that affect the maintenance of static balance ability.

Postural Changes During Exteroceptive Thin Plantar Stimulation: The Effect of Prolonged Use and Different Plantar Localizations

Somatosensory information arising from the foot has an important role in posture as well as visual and vestibular cues. Our hypothesis is that the effects of prolonged stimulation are greater than those of short stimulation and that varying the plantar location can affect postural control. Forty healthy participants were recruited and randomly assigned to four different plantar location groups: Lateral Insert (LI), Medial Insert (MI), Disharmonious Insert (DI), and Central Insert (CI). An instrumental assessment was performed before the plantar stimulation (T0), immediately after the positioning of the inserts (T1), and after 7 days of daily stimulation (T7). A follow-up was performed 15 days after (T15). The following stabilometric parameters were considered for both open eyes (OE) and closed eyes (CE) conditions: length of the sway (L) of the Center of Pressure (CoP); CoP maximum movements in the medio-lateral (X), and antero-posterior directions (Y). Comparing the effects of different plantar insert locations, the MI and CI groups were significantly different in the follow-up measures at T15, specifically for closed eyes measures. When we compared measures across time within each location group, CI group increased measures of X and Y data at T7 compared to other assessment times (T0, T1, and T15). In both MI and LI groups, L was significantly reduced, and X significantly increased at the T7 assessment compared to the T0, T1, and T15 assessments. The prolonged use of exteroceptive plantar stimulation and the location of plantar inserts may have a role to reshape postural control.