Effects of Toe-Strengthening Exercises on Medial Longitudinal Arch Height, Muscle Stiffness, and Functional Movement
1
Department of Smart Health Science and Technology, Kangwon National University, Chuncheon-si 24341, Republic of Korea
2
Republic of Korea Air Force Academy, Cheongju-si 28187, Republic of Korea
3
Department of Sports Science, College of Art and Culture, Kangwon National University, Chuncheon-si 24341, Republic of Korea
4
Department of Physical Education, Pusan National University, Busan 46287, Republic of Korea
5
Institute of Human Convergence Health Science, Gachon University, Incheon 21936, Republic of Korea
6
Division in Anatomy and Developmental Biology, Department of Oral Biology, Human Identification Research Institute, BK21 FOUR Project, Yonsei University College of Dentistry, 50-1 Yonsei-ro, Seoul 03722, Republic of Korea
*
Authors to whom correspondence should be addressed.
Appl. Sci. 2024, 14(21), 9842; https://doi.org/10.3390/app14219842
Submission received: 11 September 2024
/
Revised: 16 October 2024
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Accepted: 22 October 2024
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Published: 28 October 2024
(This article belongs to the Special Issue Advances in Sports Science and Movement Analysis)
Abstract
:Background: Prolonged training in combat boots can place significant stress on the medial longitudinal arch, potentially leading to lower-extremity muscle stiffness and an increased risk of injury. This study assessed the impact of toe-strengthening exercises on improving the lower-extremity function and functional movement in cadets undergoing training. Methods: Forty junior cadets (mean age: 22.6 years) participated in this study. The measurements included the medial longitudinal arch height, lower-extremity muscle stiffness, functional movement, and leg length. Results: Cadets who performed the toe exercises demonstrated improved lower-extremity muscle stiffness and functional movement performance (hurdle step, p = 0.010; rotary stability, p = 0.001). A significant correlation was observed between the exercise group and time (tibialis right, p = 0.008; tibialis left, p = 0.028). Conclusions: This study highlighted the potential of toe-strengthening exercises to enhance the lower-extremity function and reduce the risk of injury among cadets. However, challenges in identifying the medical history, past injuries, and specific areas of pain for each cadet were noted. These findings support the implementation of targeted toe exercises in military training programs to prevent injuries.
1. Introduction
The foot, as the distal part of the limb, supports the body weight, facilitates movement, and plays a critical role in locomotion. It consists of various anatomical structures, including bones, muscles, tendons, joints, ligaments, nerves, and blood vessels, and features three arch structures: the medial longitudinal arch (MLA), the lateral longitudinal arch, and the anterior transverse arch. These arches are crucial for shock absorption during activities such as walking and running [1]. In particular, the MLA is significant for forming the instep and primarily absorbing and dispersing shocks applied to the foot [2]. This arch facilitates proper lower-extremity function during the gait cycle and plays an essential role in shock absorption and propulsion during walking. Congenital deformities or acquired trauma affecting any element of the MLA can lead to varying degrees of clinical consequences [3].
The feet, used daily and subject to various stressors, are prone to numerous diseases due to morphological reasons, overuse, and other factors. Musculoskeletal injuries (MSKIs) to the foot are common, especially in soldiers, who frequently overuse their feet, accounting for 80% of all injuries during military training [4]. Plantar fasciitis and Achilles tendonitis are particularly prevalent, with stress fractures also commonly originating in the feet [5]. Such damage often results from the stiffness of soft tissues, including muscles and fascia, due to the prolonged use of heavy shoes and overuse [6,7]. Overuse or weakening of the internal and external foot muscles can lower the height of the MLA, increasing tension in the foot’s muscles and connective tissues [8].
For healthy foot function, it is important to maintain the height of the medial longitudinal arch. It is known that the foot’s intrinsic muscles interact with the extrinsic muscles, fascia, and ligaments to maintain arch height and contribute to stability [9]. Due to their characteristics, soldiers spend a long time wearing hard combat boots. However, due to the military performing combat and missions, not many studies have verified the efficacy of toe exercises in soldiers and compared them to human asymmetry, and studies conducted especially on Asian soldiers have not been documented to the best of our knowledge. Therefore, this study assessed the impact of toe-strengthening exercises on improving the lower-extremity function and functional movement in cadets undergoing training.
The hypotheses of this study are as follows.
- Cadets living in combat boots will have a difference in the height of the medial longitudinal arch and an imbalance in the lower extremities.
- Toe exercises will alleviate the height and muscle tension of the medial longitudinal arch, causing positive changes in improving the lower extremity imbalance.
2. Materials and Methods
2.1. Participation
Before commencing this study, approval was obtained from the Institutional Bioethics Committee of the Air Force Aerospace Medical Center (ASMC-23-IRB-003), and the person in charge explained the research process to the participants, who then signed a consent form. This study was conducted according to the principles of the Declaration of Helsinki.
The participants in this study were 40 male 3rd-year cadets from the Air Force Academy, who voluntarily participated. These cadets were part of the 2023 summer military training program (lasting 4 weeks). The inclusion criteria were as follows: (1) those who were not excluded from the 3rd-year summer military training program (4 weeks), and (2) those who could perform the toe-strengthening exercises. The exclusion criteria were as follows: (1) those who experienced cardiovascular or cardiopulmonary dysfunction, (2) those who had experienced musculoskeletal injuries over the past six months, and (3) those who were participating in other types of lower body strengthening exercise programs. The sample size was calculated using G* Power software, version 3.1.9.7 (Heinrich Heine University, Düsseldorf, Germany). By setting α = 0.05 and β = 0.80, the sample size was calculated to be 34 people. Allowing for possible dropout, 40 people were recruited. They were randomly grouped by selecting a piece of paper from an opaque box with A and B written on it: A, control (Con), n = 20; B, toe-strengthening exercise (Ex), n = 20. During participation, there were no withdrawals from the experiment. The intraclass correlation coefficient (ICC) of the NDT was the following: single measure during non-weight-bearing ICC (2,1) = 0.955, p < 0.001; average measure during non-weight-bearing ICC (2,1) = 0.984, p < 0.001; single measure during weight-bearing ICC (2,1) = 0.986, p < 0.001; and average measure during weight-bearing ICC (2,1) = 0.995, p < 0.001. The characteristics of the study participants are shown in Table 1.
2.2. Toe-Strengthening Exercise Program
The toe-strengthening exercise program is shown in Figure 1. The toe-strengthening exercise program (type of exercise, exercise intervention, repetitions, and sets), modified from our previous study [10,11], consisted of 3 items with 5 sets per exercise item, conducted 3 times a week for 4 weeks [11,12]. Before the start of the exercise, direct training was conducted on the exercise method. In the Toe-Curl Exercise (A), while the subject was sitting, the heel was placed on the floor, the instep was bent about 30°, and all the toes were kept flexed for 5 s, and then returned to the original state. In the Toe-Spread Exercise (B), the participants were asked to place their heels on the floor in a sitting state, bend their insteps about 30°, keep all the toes apart for 5 s, and then return to their original position. In the Toe-Spread-Out Exercise (C), the subject sat on a chair, dorsiflexed the ankle joint by 30°, stretched all the toes, and put the fifth toe laterally, and the first toe inward on the ground for 5 s [13]. All the exercises were performed in 5 sets of 10 repetitions, 3 times a week for 4 weeks.
2.3. Medial Longitudinal Arch (MLA) Height Measurement
The MLA height was measured using the navicular drop test (NDT). The NDT was first described by Brody in 1982 as a means of quantifying the amount of foot pronation in runners [14]. The NDT is a representative measurement method that can determine the damage and weakness of the musculoskeletal system that reduces the height of the MLA [15]. The intraclass correlation coefficient of the NDT was ICC (2,1) = 0.955, p < 0.001 for the single measure, and ICC (2,1) = 0.984, p < 0.001 for the average measure during non-weight-bearing. During weight-bearing, the single measure ICC (2,1) = 0.986, p < 0.001, and the average measure ICC (2,1) = 0.995, p < 0.001 were found.
For the specific weight-bearing measurement, the participants sat on a chair, spread their feet shoulder-width apart, flexed the knee joint 90°, and maintained the neutral position of the subtalar joint. For all the measurements, the average value was determined after measuring three times each on the left and right sides using a Martin-type anthropometer (PMII, TTM, Tokyo, Japan) [16].
2.4. Lower-Extremity Muscle Stiffness
The lower-extremity muscle stiffness was measured using a muscle tone measuring instrument (Myoton AS, Tallinn, Estonia) (Figure 2). The MyotonPRO is a device suitable for measuring the energetic stiffness of soft tissue [13]. The measurement targets were the tibialis anterior, fibularis longus, gastrocnemius, Achilles tendon, and plantar fascia [10]. The tibialis anterior, fibularis longus, and plantar fascia were measured in the supine position, and the gastrocnemius and Achilles tendons were measured in the prone position [17]. The average value was used after three measurements and remeasured when the error range was 3% or more. Among the five measurement variables (frequency, stiffness, decrease, relaxation, and creep) of the MyotonPRO, the stiffness, which represents biomechanical characteristics, was used as data.
2.5. Functional Movement Screen (FMS) Measurement
Before the Functional Movement Screen (FMS) measurement, participants were trained in 7 movements. Using a dedicated kit (Functional Movement Screen Test Kit, Functional Movement Systems, Inc., Chatham, VA, USA), 7 movements (deep squat, hurdle step, inline lunge, shoulder mobility, active straight leg raise, trunk stability push up, rotary stability) were measured. The FMS score was given out of 21 points by assigning 0 to 3 points for each motion. For all the measurements, the average value was used after measuring twice and recording using two cameras (front and side) [15].
2.6. Leg Length Measurement
The functional/structural leg length test was used to measure the leg length. The study participants were asked to spread both legs about 15 to 20 cm apart in a supine position with light clothing and keep their legs stretched. The functional leg length test was measured from the belly button to the medial malleolus, and the structural leg length test was measured from the anterior superior iliac spine (ASIS) to the medial malleolus [12]. The average value was used after measuring three times each on the left and right sides using a Martin-type anthropometer (PMII, TTM, Tokyo, Japan).
2.7. Statistical Analysis
All the results are reported as the mean ± standard deviation. All the data were analyzed using SPSS version 26.0 (SPSS Inc., Chicago, IL, USA). First, a two-way repeated ANOVA was conducted to determine the difference between the groups and time. A Scheffe test was used for the post hoc analysis. Statistical significance was accepted at p < 0.05.
3. Results
A total of 40 male cadets (exercise group, n = 20; control group, n = 20) participated in this study. The characteristics of the participants are listed in Table 1. The intraclass correlation coefficient (ICC) of the NDT was the following: single measure during non-weight-bearing ICC (2,1) = 0.955, p < 0.001; average measure during non-weight-bearing ICC (2,1) = 0.984, p < 0.001; single measure during weight-bearing ICC (2,1) = 0.986, p < 0.001; and average measure during weight-bearing ICC (2,1) = 0.995, p < 0.001.
3.1. Results of the Medial Longitudinal Arch (MLA) Height Measurement
The results of the MLA height measurements are shown in Table 2. The measurements indicated that the exercise group exhibited an increased MLA height under the non-weight-bearing and weight-bearing conditions. However, these differences were not statistically significant. The group engaging in toe exercises exhibited an increased height in the MLA under both non-weight-bearing and weight-bearing conditions, although these differences were not statistically significant.
3.2. Results of the Lower-Extremity Soft Tissue Stiffness Measurement
The results for the lower-extremity soft tissue stiffness measurement are shown in Table 3. Significant differences were observed in the left tibialis anterior for group × time (p = 0.008); right tibialis anterior for time (p = 0.015) and group × time (p = 0.028); left plantar fascia between the groups (p = 0.001) and group × time (p = 0.003); and right plantar fascia for between the groups (p = 0.019) and group × time (p = 0.005). Other factors generally showed lower stiffness levels in the exercise group; however, these differences were not statistically significant.
3.3. Results of the FMS and Leg Length Measurements
The results of the FMS and leg length tests are shown in Table 4. For deep squats, a statistically significant difference was observed over time (p = 0.045). The hurdle step showed significant differences between the groups (p = 0.010), time (p = 0.003), and group × time (p = 0.010). The active straight leg raise showed significant differences between the groups (p = 0.021) and time (p = 0.008). Other factors indicated that the exercise group scored higher in the inline lunge than the control group; however, these differences were not statistically significant.
4. Discussion
This study investigated the efficacy of toe exercises in relieving muscle tension and improving lower limb imbalance among Air Force cadets undergoing 4 weeks of military training while wearing heavy combat boots. The toe exercises significantly contributed to the local stabilization of the foot owing to their anatomical and biomechanical contributions [18]. The MLA, a key structure in the foot, plays a critical role in shock absorption and proper lower-extremity function during the gait cycle [2]. Both extrinsic and intrinsic foot muscles (IFMs) support the MLA within the active subsystem [19]. Specifically, IFMs such as the abductor hallucis, flexor digitorum brevis, and quadratus plantae play essential roles in directly stabilizing the arch by maintaining its height and flexibility [20].
The short-foot exercise (SFE) is a well-recognized exercise for strengthening the IFMs, involving the contraction of these muscles to pull the first metatarsophalangeal joint toward the calcaneus, thereby raising the MLA without flexing the toes [21]. Numerous studies have proposed SFE muscle-strengthening exercises as an effective approach to managing flat foot deformities [22]. Previous research has demonstrated that strengthening the foot muscles can reduce the navicular drop (ND) and improve the arch height, which is essential for distributing loads and absorbing shocks during movement [23].
Additionally, exercises targeting foot muscles can enhance performance in functional balance and reach challenges, which are critical for military personnel, who engage in rigorous physical activities [2]. Consistent with previous findings, this study confirmed that the height of the MLA improved in the group that performed toe exercises, although no statistically significant difference between the groups was observed. This result, although not statistically significant, is considered positive given the short duration of 4 weeks and the limited number of participants.
In the toe exercise group, the stiffness levels in the tibialis anterior and plantar fascia improved following the exercise regimen. The tibialis anterior is crucial for the dorsiflexion of the foot, and the plantar fascia is vital for supporting the arch and absorbing impact [24]. The alleviation of stiffness in the tibialis anterior and plantar fascia is primarily achieved through the restoration of mechanical elasticity and the improvement of neuromuscular coordination [25]. The stiffness of fascial and muscular tissues is mainly attributed to abnormal collagen fiber arrangement and reduced blood flow, both of which necessitate sustained mechanical stretching and exercise for resolution [26]. During this process, the realignment of collagen fibers is promoted, and the local blood flow increases, enhancing the oxygen supply and the removal of metabolic waste products [27].
Additionally, as neuromuscular coordination improves, tissue tension is relieved and functional recovery is facilitated. Toe-strengthening exercises can mitigate fascial stiffness by maintaining the arch of the foot and enhancing the functional roles of muscles associated with the plantar fascia [11]. These exercises activate the intrinsic muscles of the foot, reducing the tension on the plantar fascia and reinforcing the structural stability of the foot [28]. Through muscle activation, the pressure distribution across the foot becomes more balanced, reducing the excessive mechanical stress on the fascia and muscles, thereby contributing to the alleviation of stiffness [29]. Consequently, toe-strengthening exercises play a crucial role in reducing stiffness in the tibialis anterior and plantar fascia and improving biomechanical function during gait. The foot, with its intricate array of joints and articulations, plays a pivotal role in running and sprinting mechanics. Within this complex system, the IFM functions as a crucial local stabilizer that is integral to the active and neural subsystems, which are collectively referred to as the foot core [30]. These muscles play a key role in supporting the MLA, providing flexibility, stability, and shock absorption, and partially controlling pronation [31].
The FMS measurement results also support these findings. Lower-limb movements (deep squat, hurdle step, active straight leg raise) in the FMS showed that the toe exercise group demonstrated improved scores post-exercise. The FMS is a tool that focuses on exercises requiring mobility and stability. The improved FMS scores suggest an increased training effect in terms of injury prevention and exercise function [15]. Particularly, previous study confirmed the correlation between the G-test results of Air Force cadets, FMS, and lower extremity imbalance [32,33]. Therefore, the implementation of toe exercises for Air Force cadets with observed improved outcomes holds significant clinical importance.
In several previous studies, the effects of the short foot exercise, toe curl, and toe spread out exercise were verified as exercises to strengthen the intrinsic and extrinsic muscles of the foot, and the short foot exercise and toe spread out exercise activate the abductor muscle and the toe curl exercise is known to be mainly prescribed in the field of sports and rehabilitation because it activates the toe flexor muscles to prevent lowering of the medial longitudinal arch and is effective in improving balance ability [34]. In this study, while the short duration and limited sample size of the study may have constrained the statistical significance of some findings, the observed trends suggest that toe exercises can positively influence the MLA height, lower-extremity stiffness, and functional movement. For further follow-up studies, it is necessary to develop an exercise manual optimized for soldiers’ activities by dividing the type, frequency, time, and period of toe exercise. Further research with larger sample sizes and extended durations is warranted to substantiate these findings and fully elucidate the clinical benefits of toe exercises in the context of military training.
This study has some limitations, including the inability to thoroughly assess each cadet’s medical history, past or present injuries, and specific pain areas. Future research should address these limitations by including a comprehensive medical history and a detailed analysis of pain and injuries. These follow-up studies can lead to more comprehensive and meaningful results by increasing the number of participants and adding an analysis of female cadets, further informing injury prevention strategies for military training.
5. Conclusions
This study provided valuable insights into the effects of toe exercises on the MLA, lower-extremity muscle stiffness, and limb imbalance. Although the sample size of the study was limited and did not encompass the entire cadet population, this is a pioneering approach to these specific physical metrics in cadets. The findings demonstrated significant improvements in muscle stiffness among those who performed toe exercises. Therefore, we recommend that the frequency and time of exercise are at least three times a week, at least 30 min, and people without certain conditions change in just four weeks. However, people with certain conditions are advised to exercise for at least eight weeks. In subsequent studies, it is necessary to advance further research by increasing the number of participants, such as diversifying the group of participants and measuring females. In addition, additional research is needed by differentiating the time and exercise intensity to efficiently identify toe-strengthening exercises in soldiers.
Author Contributions
All the authors were well informed of the WMA Declaration of Helsinki—Ethical Principles for Medical Research Involving Human Subjects—and confirmed that this study firmly fulfilled the Declaration. None of the authors has financial or private relationships with commercial, academic, or political organizations or people that may have improperly influenced this study. Overall planning of the research, data acquisition, analysis, and interpretation, and major drafting and revision of manuscript submission were performed by D.-H.J. Contributing to the data acquisition, analysis, and interpretation were H.-M.J. and D.-J.P. Provision of the anatomical and clinical opinion for conceptualization, overall organization, and direct supervision of the research were undertaken by J.-Y.S. and K.-L.L. All authors have read and agreed to the published version of the manuscript.
Funding
This study was conducted with the support of the Air Force Academy’s National Treasury Research Project for 2023 (ROKAFA-23-A-1). This research was supported by the Basic Science Research Program of the National Research Foundation of Korea (NRF), funded by the Ministry of Education (NRF-2022R1I1A1A01063123).
Institutional Review Board Statement
This study was approved by the Institutional Bioethics Committee of the Air Force Aerospace Medical Center (ASMC-23-IRB-003).
Informed Consent Statement
Informed consent was obtained from all the subjects involved in the study.
Data Availability Statement
The data presented in this study are available on request from the corresponding author due to privacy.
Conflicts of Interest
The authors declare that they have no conflicts of interest.
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Figure 1.
A toe-strengthening exercise program designed to enhance the medial longitudinal arch and improve lower extremity function: (A) (a) 30 degree dorsiflexion, (b) hold for 5 s after toe flexion, (c) return to original state, Toe-Spread Exercise; (B) (a) 30 degree dorsiflexion, (b) hold for 5 s after toe spread, (c) return to original state, Toe-Spread-Out Exercise; and (C) (a) relax, (b) lifting the toe, (c) flexing little toe toward lateral side, (d) hold for 5 s after flexing great toe toward medial side.
Figure 1.
A toe-strengthening exercise program designed to enhance the medial longitudinal arch and improve lower extremity function: (A) (a) 30 degree dorsiflexion, (b) hold for 5 s after toe flexion, (c) return to original state, Toe-Spread Exercise; (B) (a) 30 degree dorsiflexion, (b) hold for 5 s after toe spread, (c) return to original state, Toe-Spread-Out Exercise; and (C) (a) relax, (b) lifting the toe, (c) flexing little toe toward lateral side, (d) hold for 5 s after flexing great toe toward medial side.
Figure 2.
MyotonPRO device used for measuring lower-extremity muscle stiffness. The MyotonPRO provides quantitative data on muscle stiffness, which is crucial for understanding the biomechanical properties of the muscles and their response to training interventions.
Figure 2.
MyotonPRO device used for measuring lower-extremity muscle stiffness. The MyotonPRO provides quantitative data on muscle stiffness, which is crucial for understanding the biomechanical properties of the muscles and their response to training interventions.
Table 1.
Participant characteristics: baseline characteristics of the exercise and control groups (mean ± SD), including age, height, weight, BMI, and leg length.
Table 1.
Participant characteristics: baseline characteristics of the exercise and control groups (mean ± SD), including age, height, weight, BMI, and leg length.
| Variable | Ex (n = 20) | Con (n = 20) | t | p |
|---|---|---|---|---|
| Height (cm) | 173.26 ± 4.25 | 174.18 ± 4.47 | −0.663 | 0.988 |
| Weight (kg) | 71.21 ± 7.36 | 69.92 ± 8.87 | 0.498 | 0.797 |
| Skeletal muscle mass (kg) | 33.75 ± 3.75 | 34.00 ± 4.14 | −0.204 | 0.809 |
| Fat mass (kg) | 11.87 ± 2.67 | 10.27 ± 3.69 | 1.569 | 0.509 |
| Body fat (%) | 16.61 ± 2.88 | 14.50 ± 4.25 | 1.839 | 0.281 |
| Body mass index (kg/m2) | 23.70 ± 2.05 | 23.02 ± 2.57 | 0.916 | 0.376 |
Values are means ± SDs; EX, exercise group; CON, control group.
Table 2.
Medial longitudinal arch (MLA) height: changes in the MLA height (non-weight-bearing and weight-bearing) for the exercise and control groups before and after the intervention, with p-values for the group and time comparisons.
Table 2.
Medial longitudinal arch (MLA) height: changes in the MLA height (non-weight-bearing and weight-bearing) for the exercise and control groups before and after the intervention, with p-values for the group and time comparisons.
| Variable | Group | Pre | Post | Group and Time | F | p |
|---|---|---|---|---|---|---|
| NWL | EX (n = 20) | 54.80 ± 4.11 | 57.05 ± 3.36 | G: | 0.037 | 0.848 |
| T: | 0.817 | 0.369 | ||||
| CON (n = 20) | 55.05 ± 4.67 | 55.45 ± 4.07 | G × T | 2.438 | 0.123 | |
| NWR | EX (n = 20) | 54.95 ± 3.81 | 57.30.3.31 | G: | 0.063 | 0.803 |
| T: | 1.713 | 0.194 | ||||
| CON (n = 20) | 55.90 ± 4.59 | 55.91 ± 4.21 | G × T | 1.713 | 0.194 | |
| WL | EX (n = 20) | 49.90 ± 3.16 | 51.40 ± 3.56 | G: | 2.482 | 0.119 |
| T: | 0.600 | 0.441 | ||||
| CON (n = 20) | 49.20 ± 4.89 | 49.15 ± 4.84 | G × T | 0.685 | 0.410 | |
| WR | EX (n = 20) | 49.85 ± 2.94 | 51.40 ± 3.80 | G: | 1.990 | 0.162 |
| T: | 1.063 | 0.306 | ||||
| CON (n = 20) | 49.15 ± 4.88 | 49.50 ± 4.58 | G × T | 0.424 | 0.517 |
Values are means ± SDs; EX, exercise group; CON, control group; NWL, non-weight load left; NWR, non-weight load right; WL, weight load left; WR, weight load right; G, group; T, time; G × T, group and time.
Table 3.
Lower-extremity muscle stiffness: muscle stiffness measurements in both groups pre- and post-intervention, with significant group × time interactions.
Table 3.
Lower-extremity muscle stiffness: muscle stiffness measurements in both groups pre- and post-intervention, with significant group × time interactions.
| Variable (Stiffness, N/m) | Group | PRE | POST | Group and Time | F | p |
|---|---|---|---|---|---|---|
| Tibialis Anterior (Left) | EX (n = 20) | 545.50 ± 47.24 | 493.85 ± 46.48 | G | 0.001 | 0.978 |
| T | 3.795 | 0.055 | ||||
| CON (n = 20) | 515.75 ± 47.63 | 524.20 ± 56.33 | G × T ## | 7.345 | 0.008 | |
| Tibialis Anterior (Right) | EX (n = 20) | 539.60 ± 48.07 | 485.90 ± 45.55 | G | 2.854 | 0.095 |
| T ** | 6.183 | 0.015 | ||||
| CON (n = 20) | 533.30 ± 47.30 | 530.55 ± 60.69 | G × T # | 5.037 | 0.028 | |
| Fibularis Longus (Left) | EX (n = 20) | 483.05 ± 50.40 | 449.01 ± 47.54 | G | 1.799 | 0.184 |
| T | 3.213 | 0.077 | ||||
| CON (n = 20) | 454.11 ± 44.45 | 447.87 ± 58.58 | G × T | 1.492 | 0.226 | |
| Fibularis Longus (Right) | EX (n = 20) | 481.50 ± 63.73 | 436.55 ± 61.99 | G | 0.834 | 0.364 |
| T | 2.553 | 0.114 | ||||
| CON (n = 20) | 445.70 ± 55.57 | 447.95 ± 55.75 | G × T | 3.119 | 0.081 | |
| Gastrocnemius (Left) | EX (n = 20) | 332.25 ± 45.55 | 303.45 ± 41.74 | G | 1.277 | 0.262 |
| T | 2.737 | 0.102 | ||||
| CON (n = 20) | 330.55 ± 41.9 | 327.15 ± 45.42 | G × T | 1.703 | 0.196 | |
| Gastrocnemius (Right) | EX (n = 20) | 343.85 ± 36.47 | 313.65 ± 36.97 | G | 0.039 | 0.844 |
| T | 2.176 | 0.144 | ||||
| CON (n = 20) | 325.30 ± 45.50 | 328.60 ± 43.36 | G × T | 3.376 | 0.070 | |
| Achilles Tendon (Left) | EX (n = 20) | 627.85 ± 77.47 | 613.75 ± 68.02 | G | 0.001 | 0.979 |
| T | 0.873 | 0.353 | ||||
| CON (n = 20) | 628.45 ± 73.64 | 612.37 ± 71.43 | G × T | 0.004 | 0.950 | |
| Achilles Tendon (Right) | EX (n = 20) | 628.41 ± 66.74 | 591.60 ± 59.07 | G | 1.980 | 0.164 |
| T | 2.409 | 0.125 | ||||
| CON (n = 20) | 635.45 ± 73.11 | 626.25 ± 65.40 | G × T | 0.867 | 0.355 | |
| plantar Fascia (Left) | EX (n = 20) | 487.30 ± 44.88 | 457.31 ± 38.47 | G +++ | 10.969 | 0.001 |
| T | 0.001 | 0.973 | ||||
| CON (n = 20) | 489.90 ± 45.10 | 519.25 ± 45.56 | G × T ## | 9.273 | 0.003 | |
| plantar Fascia (Right) | EX (n = 20) | 486.25 ± 51.33 | 459.35 ± 44.51 | G+ | 5.735 | 0.019 |
| T | 0.112 | 0.738 | ||||
| CON (n = 20) | 481.30 ± 46.02 | 515.35 ± 48.72 | G × T ## | 8.175 | 0.005 |
Values are means ± SDs; +++ p < 0.001 by groups; ** p < 0.01 by time; # p < 0.05, ## p < 0.01 by time; EX, exercise group; CON, control group; G, group; T, time; G × T, group and time; stiffness, N/m.
Table 4.
Functional Movement Screen (FMS) and leg length: FMS scores and leg length results for the exercise and control groups pre- and post-intervention, highlighting significant changes between groups and over time.
Table 4.
Functional Movement Screen (FMS) and leg length: FMS scores and leg length results for the exercise and control groups pre- and post-intervention, highlighting significant changes between groups and over time.
| Variable | Group | PRE | POST | Group and Time | F | p |
|---|---|---|---|---|---|---|
| Deep Squat | EX (n = 20) | 1.80 ± 0.83 | 2.10 ± 0.64 | G | 1.201 | 0.277 |
| T * | 4.143 | 0.045 | ||||
| CON (n = 20) | 1.95 ± 0.75 | 1.60 ± 0.59 | G × T | 0.025 | 0.876 | |
| Hurdle Step | EX (n = 20) | 1.00 ± 0.001 | 1.60 ± 0.59 | G ++ | 6.946 | 0.010 |
| T ** | 9.701 | 0.003 | ||||
| CON (n = 20) | 1.55 ± 0.51 | 1.60 ± 0.50 | G × T ## | 6.946 | 0.010 | |
| Inline Lunge | EX (n = 20) | 1.10 ± 0.31 | 1.50 ± 0.51 | G | 1.652 | 0.203 |
| T | 2.937 | 0.091 | ||||
| CON (n = 20) | 1.45 ± 0.60 | 1.45 ± 0.60 | G × T | 2.937 | 0.091 | |
| Shoulder Mobility | EX (n = 20) | 1.80 ± 0.69 | 1.95 ± 0.60 | G | 11.700 | 0.001 |
| T | 1.547 | 0.217 | ||||
| CON (n = 20) | 2.30 ± 0.86 | 2.55 ± 0.68 | G × T | 0.097 | 0.757 | |
| Active Straight Leg Raise | EX (n = 20) | 1.50 ± 0.83 | 2.15 ± 0.67 | G + | 5.592 | 0.021 |
| T ** | 7.303 | 0.008 | ||||
| CON (n = 20) | 1.40 ± 0.50 | 1.55 ± 0.60 | G × T | 2.853 | 0.095 | |
| Trunk Stability Push-Up | EX (n = 20) | 1.40 ± 0.50 | 1.65 ± 0.58 | G | 16.334 | 0.001 |
| T | 1.281 | 0.261 | ||||
| CON (n = 20) | 2.10 ± 0.79 | 2.20 ± 0.83 | G × T | 0.235 | 0.629 | |
| Rotary Stability | EX (n = 20) | 1.15 ± 0.48 | 1.90 ± 0.59 | G | 1.361 | 0.247 |
| T *** | 12.249 | 0.001 | ||||
| CON (n = 20) | 1.65 ± 0.48 | 1.65 ± 0.48 | G × T ### | 12.249 | 0.001 | |
| Total Score | EX (n = 20) | 9.75 ± 1.61 | 12.85 ± 1.75 | G ++ | 7.756 | 0.007 |
| T *** | 21.545 | 0.001 | ||||
| CON (n = 20) | 12.05 ± 2.52 | 12.95 ± 1.66 | G × T # | 6.517 | 0.013 | |
| Functional Leg Length (Left) | EX (n = 20) | 98.85 ± 2.53 | 98.22 ± 1.96 | G | 0.580 | 0.449 |
| T | 0.448 | 0.505 | ||||
| CON (n = 20) | 98.27 ± 2.89 | 98.07 ± 2.17 | G × T | 0.154 | 0.696 | |
| Functional Leg Length (Right) | EX (n = 20) | 99.02 ± 2.41 | 98.10 ± 2.27 | G | 0.455 | 0.502 |
| T | 1.095 | 0.299 | ||||
| CON (n = 20) | 98.22 ± 2.80 | 98.42 ± 2.06 | G × T | 0.195 | 0.660 | |
| Structural Leg Length (Left) | EX (n = 20) | 93.65 ± 2.87 | 92.72 ± 2.30 | G | 0.932 | 0.338 |
| T | 0.021 | 0.886 | ||||
| CON (n = 20) | 93.40 ± 3.05 | 93.15 ± 2.59 | G × T | 0.307 | 0.581 | |
| Structural Leg Length (Right) | EX (n = 20) | 93.55 ± 3.13 | 92.80 ± 2.50 | G | 0.681 | 0.412 |
| T | 0.681 | 0.412 | ||||
| CON (n = 20) | 93.87 ± 3.30 | 93.55 ± 2.62 | G × T | 0.106 | 0.745 |
Values are means ± SDs; + p < 0.05, ++ p<0.01, by groups; *p < 0.05, ** p < 0.01, *** p < 0.01 by time; # p < 0.05, ## p < 0.01, ### p < 0.001 by time; EX, exercise group; CON, control group; G, group; T, time; G × T, group and time.
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MDPI and ACS Style
Jeong, D.-H.; Jeong, H.-M.; Park, D.-J.; Sung, J.-Y.; Lee, K.-L. Effects of Toe-Strengthening Exercises on Medial Longitudinal Arch Height, Muscle Stiffness, and Functional Movement. Appl. Sci. 2024, 14, 9842. https://doi.org/10.3390/app14219842
AMA Style
Jeong D-H, Jeong H-M, Park D-J, Sung J-Y, Lee K-L. Effects of Toe-Strengthening Exercises on Medial Longitudinal Arch Height, Muscle Stiffness, and Functional Movement. Applied Sciences. 2024; 14(21):9842. https://doi.org/10.3390/app14219842
Chicago/Turabian StyleJeong, Deok-Hwa, Hyeong-Mo Jeong, Dong-Ju Park, Jun-Young Sung, and Kyu-Lim Lee. 2024. "Effects of Toe-Strengthening Exercises on Medial Longitudinal Arch Height, Muscle Stiffness, and Functional Movement" Applied Sciences 14, no. 21: 9842. https://doi.org/10.3390/app14219842
APA StyleJeong, D. -H., Jeong, H. -M., Park, D. -J., Sung, J. -Y., & Lee, K. -L. (2024). Effects of Toe-Strengthening Exercises on Medial Longitudinal Arch Height, Muscle Stiffness, and Functional Movement. Applied Sciences, 14(21), 9842. https://doi.org/10.3390/app14219842
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