This study determines (1) the correlation between mobility and balance performances with physiological factors and (2) the relationship between foot postures with anthropometric characteristics and lower limb characteristics among elderly with neutral, pronated, and supinated foot. A cross-sectional observational study was conducted in community-dwelling elderly (age: 69.86 ± 5.62 years). Participants were grouped into neutral (
The foot is an important body part because it supports body weight and organizes locomotion. However, this body part is vulnerable to daily strains when an individual walks [
Older persons with foot problems have reported multiple falls compared with those who do not have foot problems; this phenomenon may indicate a higher risk of fall in the future [
This study aimed to address the problems regarding foot posture and balance performances in elderly. Some variations in foot posture are associated with changes in lower limb motion and muscle activity, which are strongly influenced by several systemic conditions, such as neurological or rheumatological diseases [
This study aimed to (1) determine whether physiological factors, such as anthropometric data (height, body weight, and body mass index (BMI)) and lower limb characteristics (strength and endurance), are associated with balance and mobility in elderly with different types of foot postures, that is, neutral, pronated, and supinated feet; this study was also conducted to (2) determine the relationship of foot postures with anthropometric characteristics and lower limb characteristics. The result of this study may provide the basis of extensive studies on the assessments of foot posture in clinical settings. This study may also be applied to identify lower limb conditions in the early stages and predict the risk of falls. We hypothesized that the anthropometric data and lower limb characteristics were significantly correlated with balance and mobility regardless of the types of foot postures. We also hypothesized that foot posture may significantly differ in anthropometric and lower limb characteristics.
This study applied a cross-sectional design. Power analysis [
The test procedure was performed indoors, in a controlled environment. The feet of the participants were examined by one assessor using the six-item foot posture index (FPI), a clinical diagnostic tool that can distinctively quantify and classify the particular foot as neutral, pronated, or supinated posture [
Anthropometric factors, including height (m), weight (kg), and BMI (kg/m2), were evaluated, in accordance with a standard procedure.
The five-time sit-to-stand test (5-STS) was used to measure lower limb strength [
Lower limb endurance was measured using the 30 s chair rise test [
The Timed-Up and Go test (TUG) was used to measure the mobility of the participants. Several studies [
The Four-Square Step test (FSST) was used to measure balance performance. This test can be used as a reliable and valid tool to assess the dynamic standing balance of older people, including those with transtibial amputation or those with vestibular dysfunctions [
Descriptive statistics and correlation analysis were performed using SPSS 20.0 (IBM Corporation, Somers, NY). The mean and standard deviation were calculated for each variable. The significance level was set as a priori at
Table
Characteristics of the participants (
Characteristics | Neutral | Pronated | Supinated |
|
---|---|---|---|---|
( |
( |
( |
||
Mean (SD) | Mean (SD) | Mean (SD) | ||
Age (years) | 71.13 (4.674) | 67.79 (5.780) | 70.50 (6.223) | 0.196 |
Height (m) | 1.49 (0.065) | 1.50 (0.054) | 1.52 (0.056) | 0.516 |
Weight (kg) | 54.44 (14.289) | 60.24 (14.322) | 59.91 (11.99) | 0.422 |
Body mass index (BMI) (kg/m2) | 24.09 (5.238) | 26.41 (5.837) | 25.94 (4.584) | 0.474 |
Five-time sit-to-stand (sec.) | 12.93 (2.608) | 11.93 (3.050) | 11.67 (2.786) | 0.521 |
30-second chair rise (rep.) | 12.63 (2.446) | 12.00 (3.762) | 13.36 (3.342) | 0.230 |
Timed-Up and Go (sec) | 10.73 (2.566) | 10.38 (2.166) | 9.85 (2.638) | 0.484 |
Four-Square Step test (sec) | 14.33 (4.594) | 16.75 (6.427) | 13.40 (4.232) | 0.291 |
Comparisons were tested using Kruskal-Wallis analysis (nonparametric).
Spearman’s correlation coefficients (Table
Spearman (
Correlates | Mobility (TUG) | Balance (FSST) | ||||
---|---|---|---|---|---|---|
Neutral | Pronated | Supinated | Neutral | Pronated | Supinated | |
|
|
|
|
|
|
|
Height (m) | −0.395 | 0.378 | −0.402 | −0.093 | −0.013 | −0.365 |
(0.130) | (0.182) | (0.154) | (0.733) | (0.964) | (0.200) | |
|
||||||
Weight (kg) | −0.241 | −0.024 |
|
−0.006 | 0.130 | −0.187 |
(0.368) | (0.9.34) |
|
(0.983) | (0.658) | (0.523) | |
|
||||||
BMI | −0.144 | −0.122 | −0.310 | −0.109 | 0.103 | −0.020 |
(0.594) | (0.679) | (0.281) | (0.688) | (0.725) | (0.946) | |
|
||||||
LL strength |
|
|
0.484 | 0.368 | 0.163 | 0.491 |
|
|
(0.079) | (0.161) | (0.578) | (0.075) | |
|
||||||
LL endurance |
|
|
−0.242 | −0.243 | −0.356 | −0.266 |
|
|
(0.405) | (0.365) | (0.212) | (0.357) |
Comparisons were tested using Spearman correlation coefficient analysis (nonparametric).
∗Correlation is significant at the 0.05 level (2-tailed).
∗∗Correlation is significant at the 0.01 level (2-tailed).
LL: lower limb.
This study aimed to determine the associations of balance and mobility with physiological factors in elderly with neutral, pronated, and supinated foot postures. To our knowledge, studies have extensively investigated the relationship of physiological factors with balance and mobility; however, these studies have not implemented the commonly used senior fitness test to represent the physiological characteristics of participants [
In this study, height was not correlated with mobility in all types of foot. This result is not consistent with that described in a previous study [
Our results also demonstrated that weight was associated with the mobility of individuals with supinated feet; by contrast, weight was not associated with the balance and mobility of individuals with other types of foot. However, this finding is inconsistent with that in previous studies, which demonstrated a decrease in balance in individuals with a heavier body weight compared to those with a lighter body weight [
Comparisons of mean age, BMI, and number of participants in the present study and previous studies.
Author, year | Mean age (years) | Mean BMI (kg/m2) | Total participants |
---|---|---|---|
Present study | 69.08 | 25.44 | 50 (44 female; 6 male) |
[ |
40.5 | 35.2 | 59 (male only) |
[ |
22.1 | 17.4–33.8∗ | 80 (40 female; 40 male) |
[ |
22.8 | 24.6 | 108 (68 female; 40 male) |
∗Comparisons were made between groups of underweight, normal weight, overweight, and obese subjects.
A previous study [
In terms of mobility, which was measured using TUG, the participants in all of the three groups scored an average of 9.85 s to 10.73 s, which was less than the cut-off time of 13 s. For balance performance as tested by the FSST, only the participants with pronated feet scored an average of 16.75 s, with the cut-off time of 15 s [
On the basis of the results of the correlation analysis, we found that a linear rank correlation existed between lower limb strength and balance performances of the pronated and neutral foot groups. Hence, individuals with better lower limb strength may exhibit a higher ability to perform activities in standing or dynamic standing. This result is consistent with that in a previous study [
The lower limb endurance demonstrated a good linear rank correlation with balance and mobility in the neutral and pronated foot groups. Previous studies [
In the population considered for this study, the confounding factor may be caused by the administration and the psychometric properties of the assessment tool. For instance, TUG is known as an excellent outcome measure to identify the risk of fall; however, TUG is unable to identify the existing impairments in static or dynamic balance skills of an individual [
We noted several limitations of this study. First, the participants in this study were community-dwellers who are actively involved in religious classes three times to five times per day; these participants are used to walking independently around their community. This condition may have led to some effect towards their test result. The small sample size also contributed largely to the lack of strength of this finding. Thus, this study could not be used for a higher level of analysis to evaluate the physiological factors as predictors of balance and mobility due to the nonparametric approach in the analysis. With this limitation, the findings may not be generalized to a larger population. Further studies should be conducted using a larger population with a significant disability, including individuals at risk of falls. The researchers of this study also relied solely on the reliability of the FPI based on a previous study and retained only one researcher to evaluate this measure. We wish to extend our study to explore the muscle activity among different types of foot. We believe that further studies, especially those applying EMG, may enhance the objectivity and accuracy of findings to determine the potential differences among these foot postures.
Muscle properties such as strength and endurance of the lower limb may be the main factors that can affect mobility performance in elderly, regardless of their types of foot postures and thus may be an important feature to make movement possible in older persons. Thus, activities with the element of strength training should be encouraged among older persons; with this method, these individuals can preserve their basic functions for a prolonged period.
The authors declare that they have no potential conflict of interests with respect to the authorship and/or publication of this paper.
The authors wish to thank the Ministry of Education, Malaysia, for funding the research project through the Research Acculturation Grant Scheme (Ref. no. 600-RMI/RAGS 5/3 (66/2014)) and the Research Management Institute (RMI), Universiti Teknologi MARA (UiTM), for the administrative support.