Biomechanical Abnormalities in Both Sides of Individuals With Unilateral Chronic Ankle Instability During Unanticipated Jumps

Abstract

Background:

Individuals with unilateral chronic ankle instability (CAI) exhibit bilateral sensorimotor deficits, but whether these deficits contribute to bilateral biomechanical abnormalities remains unclear.

Purpose:

To evaluate bilateral ankle biomechanics in individuals with CAI during unanticipated jumps.

Study Design:

Controlled laboratory study.

Methods:

Eighteen individuals with unilateral CAI and 18 healthy controls were recruited to perform unanticipated jumps. Kinematic and kinetic data from both ankles during unanticipated jumps were simultaneously collected using an infrared high-speed motion capture system (T40, 200 Hz; Vicon) and 3-dimensional force platforms (1000 Hz; Kistler). The interactions and main effects were analyzed by statistical parametric mapping with 2-way repeated measures analysis of variance.

Results:

The injured side of CAI exhibited greater ankle plantarflexion (9.5%-36.7%; P = .01) and inversion (0%-8.7%; P = .033) angles, vertical ground-reaction force (0%-2.8% [P = .045]; 18.6%-30% [P = .013]), and smaller eversion moment (93.4%-100%; P = .035). Additionally, the uninjured side of CAI showed lower ankle dorsiflexion (41.8%-100%; P = .01) and eversion (56%-70%; P = .025) angles and moment (3.6%-40% [P = .002]; 92.1%-100% [P = .044]) but higher vertical ground-reaction force (0%-1.8%; P = .049).

Conclusions:

The study showed that the injured and uninjured sides of CAI demonstrate biomechanical characteristics associated with increased risk of ankle sprain, suggesting that management strategies should target both ankles. These findings may help in understanding and preventing ankle sprains. Further studies are needed to identify these risks.

Clinical Relevance:

Unilateral CAI may elevate the risk of ankle sprains bilaterally.

Keywords

bilateral impairment central reorganization kinematics recurrent ankle sprain unanticipated condition

In the United States, >2 million cases of ankle sprains are treated annually in emergency departments.⁴¹ Approximately 32% to 74% of individuals with ankle sprains develop chronic ankle instability (CAI), characterized by recurrent sprains, perceived instability, and residual or chronic symptoms.⁴⁵ Owing to the high recurrence rate of ankle sprains, people with CAI are often trapped in a vicious cycle of sprain-instability-reinjury, which leads to a decline in physical activity level, athletic performance, and quality of life.^15,18 Furthermore, medical expenses resulting indirectly from ankle sprains have reached billions of dollars, creating a substantial health care burden on society.⁸ Therefore, identifying risk factors for recurrent sprains in patients with CAI is crucial for individual health and society.

Individuals with CAI exhibit sensorimotor deficits, which contribute to biomechanical impairments and recurrent ankle sprains.^12,23,27 Notably, recent studies have identified a challenging phenomenon. Sensorimotor impairments in CAI are observed not only on the injured side but also on the contralateral and uninjured side.^16,24,25 People with unilateral CAI demonstrate reduced neural activity in their bilateral cerebellar VIIIb lobules.²⁸ Additionally, increased visual dependence and suppressed bilateral soleus spinal reflex excitability have been reported in patients with unilateral lateral ankle sprains.^20,21 These findings support the theory that central functional reorganization contributes to dysfunction in the uninjured side. Overall, these studies suggest that persons with unilateral CAI display bilateral sensorimotor deficits. However, bilateral deficits, such as impairments in proprioception and balance, are associated with an increased risk of ankle sprains.^7,22,24,36 Therefore, unilateral CAI may increase the risk of bilateral ankle sprains.

Biomechanical testing identifies alterations associated with ankle sprains by precisely assessing the human body's motion and load. As such, it is regarded as an essential tool for evaluating and detecting the risk of ankle sprains. However, few studies have examined the biomechanical characteristics of the uninjured side in unilateral CAI to identify the potential risk factors of ankle sprains. Additionally, previous studies commonly used anticipated movements to assess sprain risk in CAI.^30,31,40 Yet, ankle sprains in daily life and sports typically result from excessive ankle inversion and internal rotation when the body encounters unexpected stimuli. Such injuries usually occur during unanticipated movements rather than anticipated ones. Researchers have questioned the validity of anticipated movement tests, arguing that the feedforward regulation generated by such movements may confound actual biomechanical characteristics and thereby limit the reliability of ankle sprain risk assessments.^3,10 Therefore, this study employed unanticipated jump tasks and matched the bilateral limbs of both groups to investigate the biomechanical characteristics of both ankles in CAI. We hypothesized that unilateral CAI leads to biomechanical abnormalities in both ankles.

Methods

Study Design

This was a case-control study of individuals with CAI and healthy controls. All participants were informed of the experimental procedures and provided consent before data collection. This study was approved by the local ethics committee (No. 2024093).

Participants

G*Power calculation determined that 34 participants were required for 2-way repeated measures analysis of variance (group × limb). The effect size was 0.25, the power was 0.8, and the significance level was .05. Thirty-six participants were finally recruited (18 in each group). Recruitment and data collection were conducted at a local university between August 15 and October 15, 2024.

The inclusion criteria for the CAI group were as follows: (1) at least 1 previous significant ankle sprain resulting in symptoms, such as pain and swelling, and causing a minimum of 1 day of interruption in physical activity; (2) occurrence of the first sprain at least 12 months before enrollment and the most recent sprain at >3 months before enrollment; (3) a history of “giving way” or perceived instability in the injured ankle; (4) a Cumberland Ankle Instability Tool (CAIT)⁹ score ≤24; (5) negative results on anterior drawer and talar tilt tests; and (6) unilateral CAI with the right side being the dominant and injured side.

For the control group, the inclusion criteria were a CAIT score of 30, no history of ankle sprain on both sides, and the right side as the dominant side.

Participants were excluded if they had any of the following: an acute lower limb injury within the past 6 months, a history of lower limb fractures or surgical interventions, or a history of neurological disorders.

Whether the right leg of the participant is dominant was determined by the Waterloo Footedness Questionnaire.³⁸

Testing Protocol

The participants wore tight-fitting clothing and warmed up on a treadmill at 5 km/h for 10 minutes. A total of 38 infrared reflective markers were attached to the lower limbs with perforated tape, including the anterior superior iliac spine, iliac crest, posterior superior iliac spine, greater trochanter of the femur, thigh (4 markers), lateral femoral condyle, medial femoral condyle, shank (4 markers), lateral malleolus, medial malleolus, heel, and first and fifth metatarsal heads. The participants then performed unanticipated jump tests barefoot. From the start position, they ran at full effort to the takeoff position and executed a forward jump based on the screen's color cue: blue for a left single-leg jump onto the left force platform, green for a right single-leg jump onto the right platform, and red for a bilateral jump onto both platforms (Figure 1). The distance from the takeoff position to the force plate was half the height of each participant. Each color appeared randomly 3 times. Infrared light gates at the midpoint between the start and takeoff positions triggered a random color cue when passed. A successful trial required a correct response to the signal light and no foot movement for 2 seconds after landing. Kinematic and kinetic data were synchronously collected with an infrared high-speed motion capture system (T40, 200 Hz; Vicon) and 3-dimensional force platforms (1000 Hz; Kistler). This study aimed to investigate whether bilateral biomechanical abnormalities exist in those with CAI. Therefore, only bilateral jump tasks were analyzed, and we included single-leg jumps to create an unanticipated environment.

Figure 1.

Schematic of the unanticipated bilateral jump. Red arrows represent movement direction; blue solid line indicates the placement of infrared light gates; red solid line denotes the takeoff position.

Data Processing

Data were processed in Visual 3D software (C-Motion) and smoothed with a fourth-order low-pass Butterworth filter (12-Hz cutoff frequency). The landing phase was defined as the time interval between initial ground contact and peak ankle dorsiflexion angle. Biomechanical parameters analyzed during this phase included ankle angles, angular velocities, and ankle moments—all in the sagittal, frontal, and horizontal planes—and vertical ground-reaction forces (vGRFs). Data from the landing phase were normalized from 0% (initial ground contact) to 100% (peak ankle dorsiflexion angle). Initial ground contact was defined as the first time when vGRF exceeded 50 N.² Ankle angles and angular velocities were calculated relative to the proximal segments, whereas ankle moments and vGRF were computed via inverse dynamics and normalized to body weight. Joint motion directions were classified as positive for dorsiflexion, inversion, and internal rotation and negative for plantarflexion, eversion, and external rotation.

Statistical Analysis

Statistical analyses were performed in SPSS 26.0 (IBM) and statistical parametric mapping (SPM). All data were presented as mean and standard deviation. For demographic and clinical characteristics, the Shapiro-Wilk test was utilized to confirm the normality of continuous data. Normally distributed data were analyzed with an independent samples t test and categorical data by a Fisher exact test. For outcome measures, a 2-way repeated measures analysis of variance of SPM was used in comparing time series data consisting of 101 data points. When the interaction between group and limb was significant, simple effects were analyzed; otherwise, the main effects of group and limb were examined. Post hoc tests included the paired and independent samples t tests of SPM. The significance level was set at P < .05. SPM was performed via the open-access SPM 1D code (www.spm1d.org) in MATLAB R2016a (The MathWorks Inc).

Results

Demographic and Clinical Characteristics

No significant differences were found between the groups in terms of gender, age, weight, and height (P > .05). However, significant differences in CAIT scores were observed (P < .05). The CAI group had a mean score of 16.15 ± 5.32, whereas the control group had a mean score of 30. The CAI group had the first ankle sprain 15.15 ± 1.8 months before the study, the most recent sprain 4.73 ± 1.11 months ago, and an ankle sprain/“giving way” frequency of 2.62 ± 1.30 episodes per quarter (Table 1).

Table 1

Characteristics of the 2 Groups ^a

	CAI (n = 18)	Control (n = 18)	P Value
Sex: male/female	9/9	10/8	>.999
Age, y	20.80 ± 1.94	21.55 ± 2.52	.298
Weigt, kg	62.40 ± 7.21	60.55 ± 8.50	.463
Height, cm	168.85 ± 7.96	170.30 ± 7.09	.546
CAIT score	16.15 ± 5.32	30	<.001
Time since first sprain, mo	15.15 ± 1.8	—	—
Time since last sprain, mo	4.73 ± 1.11	—	—
Frequency of sprain/giving way per quarter	2.62 ± 1.30	—	—

Data are presented as No. or mean ± SD. CAI, chronic ankle instability; CAIT, Cumberland Ankle Instability Tool.

Ankle Angles

Interaction effects were observed for ankle dorsiflexion/plantarflexion angles (10.9%-35.2% [P = .019]; 48.7%-100% [P = .001]). Significant main effects of group (16%-100%; P < .001) and limb (3.3%-38.6%; P = .007) were found (Figure 2A). When compared with the dominant side of control, the injured side of CAI exhibited a higher plantarflexion angle (9.5%-36.7%; P = .01). Dorsiflexion angle was significantly lower on the uninjured side of CAI than on the nondominant side of control (41.8%-100%; P = .01). Additionally, significant differences in ankle dorsiflexion and plantarflexion angles were found between the injured side of CAI and nondominant side of control (P < .01; Table 2).

Figure 2.

Ankle angles during the landing phase. (A) Ankle dorsiflexion/plantarflexion angles. (B) Ankle inversion/eversion angles. (C) Ankle external/internal rotation angles. Light shaded areas indicate regions without significant differences (P > .05); dark gray shaded areas represent statistically significant differences (P < .05). CAI, chronic ankle instability; Con, control.

Table 2

Results of Post Hoc Test ^a

	Comparison, % (P Value) ^b
	A vs B	A vs C	B vs D	A vs D	B vs C
Dorsiflexion/plantarflexion angle, deg	NS	9.5-36.7 (.013)	41.8-100 (.01)	0-100 (<.001)	NS
Inversion/eversion angle, deg	0-5 (.046)	0-13 (.022)	56-70 (.025)	0-8.7 (.033)	NS
Inversion/eversion angular velocity, deg/s	0-24 (<.001)	3-69 (<.001)	20-50 (<.001)	3.9-58 (<.001)	0-4.6 (.035)
		89-92 (.046)		62.4-67.6 (.024)	11.9-58.9 (<.001)
		95-100 (.036)		90-90.2 (.047)	73.4-80.1 (.027)
				95.4-98.4 (.04)
Inversion/eversion moment, N·m/kg	NS	89-100 (.028)	6-39 (<.001)	93.4-100 (.035)	3.6-40 (.002)
			95-100 (.044)		53.2-82 (.007)
					92.1-100 (.044)
Vertical ground-reaction force, N·m/kg	17-34 (.006)	NS	NS	0-2.8 (.045)	0-1.8 (.049)
	94-100 (.04)			18.6-30 (.013)

Significant time intervals with corresponding P values are reported. NS, not significant.

A, injured side of chronic ankle instability; B, uninjured side of chronic ankle instability; C, dominant side of control; D, nondominant side of control. C vs D: all comparisons not significant.

For ankle inversion/eversion angles, interaction effects were observed (0%-7.7%; P = .037) with a significant main effect of limb (0%-11% [P = .026]; Figure 2B). Post hoc tests revealed that the injured side of CAI had a significantly higher inversion angle as compared with the uninjured side of CAI (0%-5%; P = .046), the dominant side of control (0%-13%; P = .022), and the nondominant side of control (0%-8.7%; P = .033). The uninjured side of CAI showed a significantly lower eversion angle as compared with the nondominant side of control (56%-70% [P = .025]; Table 2).

The main effects of group (46%-84%; P < .001) and limb (11.2%-15.2%; P = .048) were observed for ankle external and internal rotation angles (Figure 2C).

Ankle Angular Velocities

Significant interaction effects (1.5%-22.9%; P < .001) and main effects of group (0%-13%; P = .001) and limb (7%-65.5%; P < .001) were observed for ankle inversion or eversion angular velocities (Figure 3B). Post hoc tests showed significantly increased inversion angular velocity on the injured side as compared with the uninjured side of CAI (0%-24%; P < .001), the dominant of control (3%-69%; P < .001), and the nondominant side of control (3.9%-58% [P < .001]; 62.4%-67.6% [P = .024]; 90%-90.2% [P = .047]; 95.4%-98.4% [P = .04]). The injured side of CAI exhibited significantly lower eversion angular velocity than the dominant side of control (89%-92% [P = .046]; 95%-100% [P = .036]). The uninjured side of CAI showed a significant increase in inversion angular velocity as compared with the nondominant side of control (20%-50% [P < .001]). During the 0%-4.6% movement phase, the uninjured side of CAI exhibited significantly lower ankle inversion angular velocity than the dominant side of control (P = .035) but significantly increased at 11.9% to 58.9% (P < .001). Additionally, the uninjured side of CAI demonstrated higher eversion angular velocity than the dominant side of control (73.4%-80.1% [P = .027]; Table 2).

Figure 3.

Ankle angular velocities during the landing phase. (A) Ankle dorsiflexion/plantarflexion angular velocities. (B) Ankle inversion/eversion angular velocities. (C) Ankle external/internal rotation angular velocities. Light shaded areas indicate regions without significant differences (P > .05); dark gray shaded areas represent statistically significant differences (P < .05). CAI, chronic ankle instability; Con, control.

Main effects of group were observed for ankle external/internal rotation angular velocities (5.6%-9.6% [P = .041]; 20%-42% [P < .001]; 80.6%-89% [P = .008]; Figure 3C).

Ankle Moments and vGRF

Interaction effects were found for ankle inversion or eversion moments (12%-24%; P = .022), and the significant main effects of group (2.4%-10.4%; P = .036) and limb (8%-35% [P = .001]; 90%-100% [P = .025]; Figure 4B) were observed. Post hoc tests showed a significant reduction in ankle eversion moment on the injured side of CAI as compared with the dominant (89%-100%; P = .028) and nondominant (93.4%-100%; P = .035) sides of the control. The uninjured side of CAI had a significantly lower ankle eversion moment than the nondominant side of control (6%-39% [P < .001]; 95%-100% [P = .044]). During the 3.6%-40% and 92.1%-100% movement phase, the uninjured side of CAI exhibited significantly lower ankle eversion moment than the dominant side of control (P = .002, P = .044) but significantly increased at 53.2% to 82% (P = .007; Table 2).

Figure 4.

Ankle moments and vGRF during the landing phase. (A) Ankle dorsiflexion/plantarflexion moments. (B) Ankle inversion/eversion moments. (C) Ankle external/internal rotation moments. (D) vGRF. Light shaded areas indicate regions without significant differences (P > .05); dark gray shaded areas represent statistically significant differences (P < .05). CAI, chronic ankle instability; Con, control; vGRF, vertical ground-reaction force.

Interaction effects were found for vGRF (0%-2%; P = .049), and the main effect of limb was significant (0%-6.3% [P = .047]; Figure 4D). Post hoc tests revealed that vGRF on the injured side of CAI was significantly higher than the uninjured side of CAI (17%-34%; P = .006) and the nondominant side of control (0%-2.8% [P = .045]; 18.6%-30% [P = .013]). Additionally, vGRF on the uninjured side of CAI was significantly greater than the dominant side of control (0%-1.8% [P = .049]; Table 2).

Discussion

The major findings of our study demonstrated that the injured side of the CAI group exhibited greater ankle plantarflexion and inversion angles, ankle inversion angular velocity, and vGRF and smaller eversion moment. Additionally, the uninjured side showed lower ankle dorsiflexion and eversion angles and moment but higher ankle inversion angular velocity and vGRF. These findings suggested that unilateral ankle instability may lead to biomechanical characteristics associated with an increased risk of bilateral ankle sprains. To the best of our knowledge, this study is the first to investigate bilateral ankle biomechanical characteristics in individuals with unilateral CAI during unanticipated jumps. These findings provide new biomechanical evidence regarding the risk of bilateral ankle sprains in unilateral CAI.

Ankle Angles and Angular Velocities

An increase in ankle plantarflexion reduces congruence between the superior and inferior surfaces of the talus, placing the ankle joint in an open and vulnerable state.¹⁴ We found a greater ankle plantarflexion angle on the injured side of CAI. By contrast, Herb et al¹³ reported the opposite result. This discrepancy may be due to the different movement patterns employed. They used anticipated jump movements, allowing participants to adjust their movement strategy through feedforward mechanisms before landing to cope with potential risks.⁴² Specifically, this movements involves reducing ankle plantarflexion angle to position the ankle joint in a closed and stable position. However, unanticipated movements rely on feedback mechanisms, and reactive lateral ankle neuromuscular strategies address risk.¹¹ Owing to the limited response time and sensory information, the participants were unable to quickly switch to a protective movement state for ankle sprain. This inability may explain the increased ankle plantarflexion angle observed in our study. This implies that anticipated movements may lead to protective strategies, which hinder a complete reflection of the neuromechanical changes or deficits in individuals with CAI. Furthermore, researchers have emphasized that a feedforward adjustment mechanism may result in greater fatigue and muscle contraction weakness in persons with CAI during later task stages, thereby diminishing their ability to cope with ankle instability.⁶

Our study observed that ankle dorsiflexion angle was smaller on the uninjured side of CAI. During the landing phase, the lower limbs must absorb the impact forces and maintain postural stability. On one hand, a large ankle dorsiflexion angle effectively dissipates the impact force applied to the ankle joint, reducing the load on the lateral ankle ligaments.³⁵ On the other, an increased dorsiflexion angle can align the ankle joint closely, stabilizing the joint.³⁵ It also lowers the center of mass, thereby improving postural stability during landing.³⁴ Therefore, reduced ankle dorsiflexion angle on the uninjured side of CAI may be associated with an increased risk of ankle sprain.

Excessive ankle inversion increases the medial displacement of the talus, thereby increasing tension on lateral ankle ligaments.⁴ Epidemiologic data indicated that 70% of ankle sprains are caused by such excessive inversion movements.¹ Our results revealed a considerable increase in ankle inversion angle on the injured side of CAI, whereas the uninjured side exhibited a smaller ankle eversion angle. Given the observed results of ankle sagittal angles, when the injured ankle suddenly underwent plantarflexion and inversion, the uninjured side was unable to adequately adjust the foot position to compensate for the instability of the injured ankle. This process might have impaired overall postural stability and increased the risk of ankle sprain on the uninjured side.

The mechanism underlying reduced ankle eversion angle on the uninjured side after unilateral injury may be related to the extensive neural network connections of the sensorimotor systems. On the injured side of CAI, reduced agonist muscle activity and increased antagonist muscle activation occur as an adaptive response to pain, and a similar adaptation response may be observed on the uninjured side.³⁷ Regarding the nervous system, Edgley et al⁵ reported that a group of interneurons receives input not only from supraspinal pathways but also from Ia and II afferent fibers and bilateral joint information. Motor pathways, such as the corticospinal tract, involve crossed and bilateral control.¹⁶ Meanwhile, Shen et al³³ reported that individuals with CAI demonstrate increased amplitude of low-frequency fluctuation and regional homogeneity in the ipsilateral postcentral gyrus, right precentral gyrus, and right middle frontal gyrus. Given that the motor cortex of 1 hemisphere controls contralateral movements, this result suggested a reorganization of the motor cortex governing the uninjured limb in CAI. However, Maricot et al²⁹ indicated that central adaptive changes related to motor function in those with CAI may affect descending motor pathways, leading to long-term sequelae and recurrent ankle sprains. Therefore, sensorimotor impairments on the injured side may cause maladaptive reorganization of centrally mediated motor control strategies, contributing to coronal plane instability in both ankles.

Excessive ankle inversion angular velocity increases the rate of stress loading on the lateral ankle, further exacerbating strain on lateral ligaments.¹⁷ Our study found a considerable increase in ankle inversion angular velocity on both sides of CAI, indicating impaired control of coronal plane motion in both ankle joints. Lin et al²⁶ suggested that the insufficient activation of peroneus longus and tibialis anterior in individuals with CAI may prevent the suppression of excessive ankle inversion, leading to increased ankle inversion angular velocity. Sousa et al³⁶ reported that unilateral CAI results in increased bilateral errors in force sense. Therefore, impaired force sense on the uninjured side may reduce the stabilizing role of the peroneus muscles in controlling excessive inversion, thereby increasing ankle inversion angular velocity.³⁶

Ankle Moments and vGRF

Ankle eversion moment is generated by a ground-reaction force acting on the center of the ankle joint. A large ankle eversion moment helps to correct excessive ankle inversion. Our study demonstrated that ankle eversion moment was significantly reduced on both sides of CAI. Wan et al³⁹ reported that individuals with unilateral CAI exhibited a lateral shift in bilateral plantar pressure during walking. A shift of the center of pressure toward the lateral edge of the foot increases the moment arm of ground-reaction force, thereby generating a large inversion moment (ie, a smaller eversion moment during loading).⁴⁴

An increase in vGRF subjects the musculoskeletal structures of the lower limbs to considerable loading over a short period, particularly the ankle joint, which is the first to make contact with the ground.¹⁹ Our results showed greater vGRF on both sides of CAI. Increased vGRF may be associated with a decrease in ankle dorsiflexion angle. Wright et al⁴³ employed computer simulations to demonstrate that a greater ankle dorsiflexion angle reduces the external moment arm of ground-reaction force at the subtalar joint. Additionally, a high ankle dorsiflexion angle provides an advantageous position and long duration for the plantarflexors to dissipate vGRF.³²

Practical Implications

This study matched the bilateral limbs of individuals with CAI and control on the same side and selected the unanticipated bilateral jump for testing. The results revealed that biomechanical abnormalities in both sides of individuals with unilateral CAI. Specifically, the uninjured side displayed open and vulnerable ankle posture, reduced ankle control, and increased joint loading. These changes increased the risk of ankle sprain on the uninjured side of CAI and may impair the ability to compensate for the instability of the injured ankle during unanticipated jumps, compromising overall postural stability. Our study highlights that individuals with unilateral CAI are at risk of ankle sprains in both ankles during unanticipated jumps. These findings offer valuable insights for researchers and clinicians in developing ankle sprain rehabilitation strategies of CAI. Preventing and mitigating the effect of unilateral CAI on the uninjured limb should be a key focus in future research.

Limitations

Our study has limitations. First, case-control studies cannot establish causal relationships between the observed variables and injuries; prospective studies are warranted to further explore these associations. Second, the inclusion of only young participants may limit the generalizability of the findings to other age groups. Finally, some results approached the threshold for statistical significance. Thus, studies with larger sample sizes are required to confirm these findings.

Conclusion

Our study showed that the injured and uninjured sides of CAI demonstrate biomechanical characteristics associated with an increased risk of ankle sprain, suggesting that management strategies should target both ankles. These findings may help in understanding and preventing ankle sprains. Further studies are needed to identify these risks.

Footnotes

Final revision submitted July 27, 2025; accepted September 12, 2025.

One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported by the Shanghai Municipal Education Commission Program for Empowering Disciplinary Advancement Through AI-Driven Scientific Paradigm Reform (project: “AI-Driven Research and Application in Sports Biomechanics: Precise Modeling, Key Point Recognition, and Sports Injury Diagnosis”) and the National Natural Science Foundation of China (12472327). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Ethical approval for this study was obtained from the ethics committee of Wuhan Sports University (No. 2024093).

ORCID iD

Peng Chen

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