Ankle Dorsiflexion and Core Endurance Predict Landing Mechanics in Collegiate Basketball Players — Field Tests That Map to Drop Vertical Jump Biomechanics

Table of Contents

1. Key Highlights
2. Introduction
3. Why landing mechanics determine both performance and injury risk
4. Translating lab biomechanics into field-friendly tests
5. The top-level findings: what mapped and what didn’t
6. Why ankle dorsiflexion ROM emerges as the primary mechanical gateway
7. Lateral core endurance — the often-overlooked stabilizer
8. Why balance and single-leg hop distance did not predict DVJ landing mechanics
9. Practical application: field tests to prioritize and how to run them
10. Interventions informed by the findings
11. How coaches can build a practical screening protocol (a 3-step approach)
12. Study design and credibility: strengths that matter to practitioners
13. Limitations and cautions for interpretation
14. From evidence to practice: case vignettes
15. Where the evidence points next
16. Practical checklist for implementation
17. Final perspective
18. FAQ

Key Highlights

• Ankle dorsiflexion range of motion and core endurance (not balance or single-leg hop) showed the strongest, consistent associations with landing kinetics and kinematics during a drop vertical jump in male collegiate basketball players.
• Simple field measures — ankle ROM, trunk flexion ROM, and the 5-level side bridge — together explained a large portion of variance in ankle and knee joint moments during landing, suggesting practical screening tools for coaches and clinicians.

Introduction

Landing after a vertical jump compresses the body’s kinetic chain and represents a frequent moment of both performance opportunity and injury risk in court sports. Coaches and medical staff need rapid, reliable ways to flag athletes whose movement patterns during landing place them at risk or limit performance. High-precision laboratory tools — three-dimensional motion capture and force platforms — deliver rich biomechanical data but remain impractical for routine use outside specialized labs. This study bridges laboratory insight and field practice by asking which low-cost, field-friendly fitness tests relate meaningfully to landing mechanics measured during a standardized drop vertical jump (DVJ). The answers point to targeted screening and straightforward interventions that can be implemented on the court.

The research tested a battery of health- and skill-related fitness measures against kinematic and kinetic variables from the first landing of a DVJ in 18 male collegiate basketball players. The patterns that emerged implicate ankle dorsiflexion range of motion (DF ROM) and core endurance, particularly lateral core capacity, as the most informative field measures for predicting how the body absorbs and controls forces on landing.

The following sections unpack the study’s findings, explain their biomechanical logic, and translate them into step-by-step guidance for coaches, strength & conditioning practitioners, and physiotherapists.

Why landing mechanics determine both performance and injury risk

Every landing is a test of force attenuation, segmental coordination, and neuromuscular control. In basketball and volleyball, repeated landing exposes the lower limbs to high-impact loads that must be absorbed and redirected efficiently. Key biomechanical variables include:

• Peak ground reaction forces (vertical and mediolateral components).
• Joint angles and displacements at the ankle, knee, and hip during initial contact and the subsequent absorption phase.
• Joint moments, which reflect the torque demands on muscles to control motion and dissipate energy.

Suboptimal landing mechanics — shallow knee flexion, excessive knee abduction (valgus), limited ankle dorsiflexion, or poor trunk control — concentrate loads at vulnerable tissues (for example, the anterior cruciate ligament) and reduce the ability to decelerate the body safely. Conversely, controlled knee and ankle flexion and stable pelvic-trunk alignment prolong the time over which forces are dissipated and enable more powerful subsequent rebounds.

Laboratory-grade measures capture these components objectively, but the key question for practitioners is whether any field-level tests reliably indicate problematic landing mechanics. The study under review examined that precise question.

Translating lab biomechanics into field-friendly tests

The investigators evaluated a set of commonly used, low-cost assessments that map to the main components of physical fitness implicated in landing mechanics:

• Health-related measures: core endurance (20 s sit-up; 8-level abdominal bridge; 6-level supine bridge; 5-level side bridge) and flexibility (trunk, hip, knee, ankle ROM).
• Skill-related measures: dynamic balance (Y-Balance Test, normalized score) and lower-extremity power (dominant single-leg hop distance, D-SLHD).

Each participant performed the field battery on day one and a DVJ protocol in the biomechanics lab on day two. The DVJ first landing (from a 45 cm drop, immediate maximal rebound) provided synchronized kinematics (Vicon, 200 Hz) and kinetics (force plates, 1,000 Hz). The investigators analyzed associations with Pearson correlations and linear regression, then built multiple regression models where appropriate.

The study sought to identify which field tests explained meaningful variance in DVJ biomechanics, with sufficient effect sizes to justify use as proxies for more complex analysis.

The top-level findings: what mapped and what didn’t

The study’s main results prioritize ankle dorsiflexion ROM and specific core endurance tests as field measures that relate to landing mechanics. Skill-related tests — Y-Balance Test score and dominant single-leg hop distance — did not show significant associations with the DVJ biomechanical variables considered.

Key statistically significant univariate relationships included:

• Ankle dorsiflexion ROM and mediolateral ground reaction force (GRFY): r = −0.48, p = 0.025, R^2 = 22.9%. Greater dorsiflexion ROM was associated with lower mediolateral GRF during landing.
• Ankle dorsiflexion ROM and knee angle displacement (ADkneX): r = −0.64, p = 0.004, R^2 = 41.2%. More dorsiflexion ROM associated with smaller angle displacement at the knee across the landing phase.
• Ankle dorsiflexion ROM and ankle plantarflexion moment (MankX): r = 0.59, p = 0.009, R^2 = 35.3%. Greater dorsiflexion ROM associated with larger plantarflexion joint moment.
• Ankle plantarflexion ROM and ankle angle at initial contact (AkneX): r = −0.58, p = 0.012, R^2 = 33.6%.
• Trunk flexion ROM and ankle plantarflexion moment (MankX): r = 0.57, p = 0.014, R^2 = 32.3%.
• 5-level side bridge and hip adduction angle displacement (ADhipY): r = −0.51, p = 0.014, R^2 = 26.3%.
• 5-level side bridge and knee joint moment (MkneX): r = 0.65, p = 0.033, R^2 = 54.7%.
• 8-level abdominal bridge and MkneX: r = 0.59, p = 0.01, R^2 = 35.0%.

Multiple regression results identified two practical models:

• MkneX was predicted by the 5-level side bridge score alone (MkneX = 0.011 × 5-level side bridge + 1.103; p = 0.004), explaining 45.5% of variance.
• MankX was predicted by ankle dorsiflexion ROM and trunk flexion ROM together (MankX = 0.017 × ankle DF ROM − 0.064 × trunk flexion ROM + 1.426; p = 0.001), explaining 61.2% of variance.

The combined evidence points to ankle mobility and lateral/core endurance as the field measures most strongly tied to landing mechanics in this cohort.

Why ankle dorsiflexion ROM emerges as the primary mechanical gateway

Ankle dorsiflexion controlled through the tibial progression over the foot plays a central role in how the lower limb absorbs impact. Mechanically and functionally, the ankle affects landing in at least three ways:

1. Timing and depth of knee flexion. Sufficient dorsiflexion permits the tibia to travel forward over the foot, facilitating larger knee flexion excursions during the absorption phase. Increased knee flexion lengthens the time to dissipate vertical impact energy and reduces peak forces measured at the ground. The study found that greater dorsiflexion ROM correlated with smaller mediolateral GRF and smaller knee angle displacement during landing, consistent with a more controlled, extended dissipation window.
2. Redistribution of load. Athletes with larger ankle DF ROM tend to land with more uniform pressure distribution, often more on the forefoot at initial contact. That redistribution reduces sudden spikes in localized loading and limits compensatory movements proximal to the ankle.
3. Moment generation and propulsion capacity. Greater DF ROM was also associated with larger ankle plantarflexion moments (MankX) during the absorption/propulsion sequence. This reflects improved leverage and the capacity for the plantarflexors and Achilles tendon to generate and buffer forces across the eccentric-to-concentric transition.

Practically, small restrictions in ankle DF ROM can force compensations up the chain — increased knee valgus or excessive trunk adjustments — that both degrade performance and elevate injury risk over repeated exposures.

Lateral core endurance — the often-overlooked stabilizer

Core endurance is not a monolith. The lateral subsystem (gluteus medius, obliques) has distinct responsibilities: maintaining pelvic level, controlling hip adduction, and stabilizing the trunk in the frontal plane through dynamic tasks. The 5-level side bridge is a graded test that stresses lateral core endurance and dynamic stabilization; performance on this test correlated strongly with hip adduction displacement and knee joint moments during DVJ landings.

Mechanics at play:

• Better lateral core endurance reduces contralateral pelvic drop, limiting hip adduction on the stance leg and helping prevent knee valgus collapse.
• Strong lateral core control supports more neutral alignment during the absorption phase, translating to lower frontal-plane excursions at the knee and hip.
• The 5-level side bridge explained a substantial share of variance in MkneX in both univariate and multivariate analyses, indicating its value as a field proxy for the trunk-pelvis control that moderates knee loading.

The 8-level abdominal bridge (anterior core) also related to knee joint moment, but when combined with the lateral bridge in multivariate modeling, the lateral bridge captured the dominant portion of relevant variance for MkneX. For practical screening, lateral core measures appear especially informative.

Why balance and single-leg hop distance did not predict DVJ landing mechanics

The study did not find meaningful associations between the Y-Balance Test score or dominant single-leg hop distance (D-SLHD) and the DVJ biomechanical measures. Several reasons explain this:

• Task specificity: The Y-Balance Test assesses reach distance and balance in three directions on a static stance condition; it captures a different demand profile than a dynamic, bilateral drop-landing followed by an immediate maximal rebound. Likewise, D-SLHD measures horizontal reactive power and projection angle choices, which differ mechanically from the vertical, bilateral landing patterns of the DVJ.
• Neuromuscular recruitment differences: Balance training and tests typically load lower-threshold motor units and postural control systems. Vertical jump absorption and rebound require rapid, high-force eccentric–concentric muscle actions and coordinated multi-joint torque sequencing. Transfer between modalities can be limited, particularly in trained athletes whose adaptations have specialized.
• Measurement sensitivity: The Y-Balance Test and single-leg hop are reliable measures for certain purposes (injury risk screening, return-to-sport decision-making), but they may fail to capture specific timing and torque variables measured in DVJ first-landings (e.g., precise joint moments and short-latency force peaks).

The absence of association does not negate the value of these tests in the broader assessment battery. It does, however, caution against assuming that high performance in these tasks will necessarily indicate safe or efficient landing mechanics in bilateral vertical jump contexts.

Practical application: field tests to prioritize and how to run them

The study supports a streamlined field battery for coaches and clinicians aiming to monitor landing-related risk factors. Prioritize the following measures:

1. Ankle dorsiflexion ROM
   • Test: Active dorsiflexion ROM with EasyAngle or inclinometer, knee bent and extended tests for gastrocnemius/soleus differentiation, or a weight-bearing lunge test (tibia forward-over-foot).
   • What to record: Max dorsiflexion angle (degrees) per limb. In this study the mean dominant-limb DF ROM was approximately 63.6° (SD 8.8°) among male collegiate basketball players.
   • Interpretation: Lower DF ROM associated with higher mediolateral GRF and greater knee angle displacement during landing. Track reductions across a training block or identify athletes with lower DF ROM relative to team norms for mobility interventions.
2. Trunk flexion ROM
   • Test: Standing measurement of C7–S1 distance in neutral, maximum forward bend, and extension to quantify flexion/extension range.
   • What to record: Range from neutral to forward flexion in cm. Mean in the cohort: trunk flexion ROM ~13.4 cm (SD 2.2 cm).
   • Interpretation: Trunk flexion ROM contributed to ankle plantarflexion moment during landing. Restriction can shift demands to distal joints.
3. 5-level side bridge (lateral core endurance)
   • Test: Graded side bridge progression with timed holds and controlled limb movements; score reflects ability to sustain increasingly challenging lateral bracing positions.
   • What to record: Time held at each level or cumulative score based on test protocol. Mean side bridge time in study: 55.5 ± 19.4 s.
   • Interpretation: Better performance corresponded to reduced hip adduction displacements and explained substantial variance in knee joint moment during landing. Use as a screening tool for pelvis-trunk control.
4. 8-level abdominal bridge (anterior core endurance)
   • Test: Multi-level anterior plank progressions; useful supplementary measure.
   • Interpretation: Correlated with knee moment in univariate models but offered less independent predictive power when combined with lateral bridge.

How to embed testing into routine:

• Baseline and seasonal checks: Preseason, midseason, and postseason evaluations capture changes due to training load, fatigue, and injury exposure.
• Rapid screens: Use ankle DF ROM and 5-level side bridge as quick monitors after travel or during heavy training blocks when lab-based testing is not feasible.
• Integration with video screening: Combine field test results with simple video analysis of free- or training-court vertical jumps (frontal and sagittal plane) to identify athletes whose field scores and visual landing faults align.

Interventions informed by the findings

When field screening highlights limited ankle DF ROM or poor lateral core endurance, interventions should target the specific restriction or deficit with progressive, evidence-informed drills. Practical recommendations:

For ankle dorsiflexion ROM:

• Mobility drills: Weighted or unweighted ankle dorsiflexion lunges with focus on forward tibial progression while maintaining foot contact. Use progressive sets of 2–3 sets of 6–10 controlled repetitions per side, daily or every other day when mobility limitations are present.
• Soft-tissue work: Calf (gastrocnemius/soleus) foam rolling and cross-fiber mobilizations may assist tissue compliance.
• Joint mobilization: Clinician-guided talocrural posterior glide mobilizations with active dorsiflexion can produce measurable ROM gains.
• Eccentric calf strengthening: Slow eccentric heel drops (3 sets × 12–15 reps) emphasize lengthening capacity of the Achilles–calf complex and support tendon loading tolerance.

For lateral core endurance:

• Progressive side-bridge progressions: Begin with static side planks with knee support, progress to full-leg side planks, add limb movements and instability as tolerated. Prescribe 2–4 sets with time-based holds aligned to individual capacity (e.g., build toward 45–60 seconds per side).
• Dynamic lateral stabilization: Single-leg deadlifts, lateral band walks, and resisted clamshells reinforce gluteus medius activation.
• Integration into plyometrics: Add lateral stabilization cues to landing drills, progressing from low-height drop landings with controlled deceleration to sport-specific reactive jumps.

Programming note: Combine mobility and strength work with plyometric and landing technique training. Improvements in ROM and core capacity will be most effective when athletes practice coordinated, tolerated landings that reinforce safer joint sequencing.

How coaches can build a practical screening protocol (a 3-step approach)

Step 1 — Quick triage (5–10 minutes)

• Examine ankle DF ROM using a weight-bearing lunge test on each limb.
• Perform a side bridge test (time to failure or graded level reached) for each side.
• If ankle DF ROM or side bridge performance falls below team thresholds, flag the athlete for a focused follow-up.

Step 2 — Focused follow-up (20–30 minutes)

• For flagged athletes: quantify trunk flexion ROM and ankle plantarflexion ROM with an inclinometer or simple tape measurement.
• Video a standard drop vertical jump (frontal and sagittal) for 2–3 trials. Look for asymmetric knee valgus, limited knee flexion, or excessive trunk collapse.
• Assign an individualized program combining mobility, lateral core work, and low-level landing retraining.

Step 3 — Progress monitoring (every 4–6 weeks)

• Reassess DF ROM and side-bridge performance.
• Perform a DVJ video retest and note improvements in knee alignment, knee flexion depth, and trunk control.
• Reintegrate to higher plyometric loads once targeted improvements are evident and the athlete demonstrates control across sport-specific tasks.

This simple, repeatable workflow aligns with the study findings where ankle DF ROM and lateral core endurance best predicted DVJ biomechanics.

Study design and credibility: strengths that matter to practitioners

Several methodological choices strengthened the study’s credibility:

• Laboratory standardization: DVJ kinematics were captured with an 8-camera Vicon system (200 Hz) synchronized to force plates (1,000 Hz). Data filtering followed standard practice (Butterworth low-pass filters).
• Clear testing order and warm-up: Physical tests preceded the DVJ on a separate day to minimize acute fatigue confounders. Warm-up procedures aligned with typical team routines.
• Objective scoring systems: The study used defined, graded core endurance protocols (the Chinese 8-level/6-level/5-level bridge systems) and standardized ROM assessments.
• Statistical rigor: The authors conducted a priori power analysis, used Pearson correlations and linear regression, checked multicollinearity via VIF, and reported adjusted R^2 for model fit.

These design choices support the practical relevance of the reported associations while acknowledging the constraints that follow.

Limitations and cautions for interpretation

The study provides useful guidance for field screening but requires careful interpretation:

• Cross-sectional design: The associations describe relationships at a single time point; they do not prove causation. Improvements in ankle ROM or core endurance may not automatically cause changes in landing biomechanics without concurrent technique training.
• Sample characteristics: The cohort consisted of 18 male collegiate basketball players (mean age ~21.9 years), all left-limb dominant. Results may not generalize to female athletes, younger athletes, elite/professional players, or those with different limb dominance distributions.
• Small sample size: Although an a priori power analysis justified the sample for the expected effect sizes, larger and more diverse samples would improve the precision of predicted thresholds.
• Measurement tools: The ankle ROM was measured with an inclinometer-like device and specific protocols; results can vary by tester and method. Consistent testing technique is essential for longitudinal monitoring.
• Scope of field tests: The chosen skill-related measures did not predict DVJ biomechanics here, but that does not eliminate their value in other contexts (return-to-sport decisions, unilateral dynamic control, or horizontal power assessment).
• Missing neuromuscular data: Electromyography (EMG) was not included. EMG would clarify which muscles change activation patterns with altered ROM or core endurance.
• Temporal waveform analysis: The study used discrete variables from the landing phase. Statistical parametric mapping (SPM) of entire waveform data could provide deeper temporal insights.

Practitioners should view the findings as a powerful starting point for screening and intervention, and integrate them with sport-specific judgements and broader monitoring.

From evidence to practice: case vignettes

Two brief vignettes illustrate how teams can apply these results.

Case A — Collegiate guard with repeated ankle sprains: A 20-year-old guard complains of stiffness at the rear of the ankle and demonstrates poor DF ROM on the weight-bearing lunge (45° vs. team mean ~64°). Video shows a relatively stiff landing with short knee flexion excursion and slight medial knee collapse. The practitioner prescribes ankle joint mobilizations, talocrural glides, daily dorsiflexion mobilization drills, and eccentric calf strengthening. After 6 weeks, DF ROM increases to 58°, mediolateral knee displacement on training DVJs decreases, and subjective landing confidence improves.

Case B — Forward with lateral trunk drift on landings: A 22-year-old forward exhibits early ipsilateral pelvic drop and hip adduction during landing. The 5-level side bridge score is low compared with teammates (short hold times and early failure at level 2). The practitioner assigns side-bridge progressions, gluteus medius activation drills, and lateral stabilization tasks embedded in plyometric progressions (low-to-moderate height). Over 8 weeks the athlete displays reduced hip adduction on videoed DVJs and reports fewer episodes of knee soreness after games.

These cases reinforce that targeted, measurable interventions guided by the field tests can align with expected biomechanical improvements.

Where the evidence points next

The study highlights productive directions for additional research and applied development:

• Replicate with mixed-gender and larger samples to quantify sex-specific mechanics and thresholds.
• Combine field screening with EMG and SPM to map temporal muscle activation patterns and waveform-level associations.
• Longitudinal intervention trials that improve ankle DF ROM and lateral core endurance and evaluate consequent changes in DVJ biomechanics and injury rates.
• Develop normative team- and sport-specific ranges for DF ROM and side-bridge performance to guide individualized thresholds.
• Create simple clinician-facing decision trees and mobile-app enabled tests to support widespread adoption of these screening tools.

Each of these steps would refine the utility of field tests as early warning signals for suboptimal landing mechanics and injury risk.

Practical checklist for implementation

Use this quick checklist to operationalize the study’s findings in a team setting:

• Preseason
  • Measure ankle DF ROM bilaterally (weight-bearing lunge or inclinometer).
  • Record 5-level side bridge and 8-level abdominal bridge performance.
  • Video standardized DVJ (frontal and sagittal) for baseline landing mechanics.
• Weekly/biweekly
  • Run quick DF ROM checks and side-bridge holds for flagged athletes.
  • Document acute changes after travel or heavy training load.
• Intervention triggers
  • DF ROM significantly below team mean or historical baseline.
  • Side-bridge performance indicating lateral endurance deficit.
  • Video shows excessive knee valgus, limited knee flexion, or lateral trunk collapse.
• Reassessment
  • After 4–8 weeks of intervention, reassess ROM, core endurance, and DVJ video.
  • If field scores improve but DVJ mechanics do not, escalate to biomechanical analysis or specialist referral.

This protocol emphasizes rapid screening, targeted remediation, and evidence-informed reassessment.

Final perspective

Field-friendly metrics that correlate with lab-measured landing mechanics allow coaching and medical staff to triage athletes efficiently, prioritize corrective work, and monitor adaptations without routine laboratory access. Ankle dorsiflexion ROM and lateral core endurance emerge as especially practical, interpretable markers that map onto critical kinetic and kinematic landing variables. Implemented together with progressive mobility, strength, and movement retraining, these assessments provide a pragmatic path to safer and more effective jump-landing performance.

FAQ

Q: Can ankle dorsiflexion ROM and side-bridge tests replace lab-based motion capture and force plate analysis? A: They do not replace lab measures. The field tests indicate likely patterns and flag athletes for closer review. When complex or borderline cases arise — persistent symptoms, elite-level decisions, or return-to-play after significant injury — laboratory analysis remains the gold standard.

Q: Do these findings apply to female athletes or younger players? A: This study focused on male collegiate basketball players. Evidence suggests sex and age can influence landing mechanics and neuromuscular strategies; similar screening will likely be informative but requires validation in female and younger populations before applying exact thresholds.

Q: How often should teams screen ankle ROM and core endurance? A: Practical schedules include preseason baseline, midseason, and postseason assessments, with more frequent monitoring (weekly or biweekly) for athletes returning from injury, reporting soreness, or exposed to increased training load.

Q: What constitutes “low” ankle dorsiflexion ROM in practice? A: Absolute cutoffs are not definitive yet. In the study the group mean for dominant-limb DF ROM was ~63.6°. Use team-specific norms and monitor intra-athlete changes; an athlete substantially lower than team mean or who shows reductions over time merits attention.

Q: Could increasing ankle dorsiflexion harm jump performance? A: Reasoned ankle mobility work combined with strength and plyometric training enhances joint function and tends to support both safer landings and effective propulsion. Mobility done in isolation without strength or motor control work may not transfer optimally; interventions should be integrated.

Q: Which single exercise produces the fastest gains in lateral core endurance? A: Progressive side-plank variations with controlled repetitions and increasing difficulty (leg lifts, arm reaches, instability) yield consistent improvements. Combine with gluteus medius strengthening and task-specific landing drills for best transfer.

Q: Why didn’t the Y-Balance Test predict DVJ mechanics here? A: The Y-Balance Test captures reach and static-dynamic balance control under different conditions and is valuable for many purposes. The DVJ is a high-impact, bilateral, and rapid task with different neuromuscular demands. Lack of association reflects task specificity more than irrelevance of balance measures.

Q: Should coaches prioritize mobility or strength interventions first? A: Assess the primary deficit. If ankle DF ROM is restricted, start with mobility and tissue work, integrated early with strength to preserve joint control. For lateral core deficits, begin lateral stability and gluteal strength work and embed mobility as needed. Progress both streams together toward landing-specific plyometrics.

Q: How large were the study effects — are they clinically meaningful? A: Several correlations explained substantial variance (e.g., ankle DF ROM accounted for ~41% of variance in knee angle displacement; combined ankle DF ROM and trunk flexion ROM explained ~61% of variance in ankle plantarflexion moment). These effect sizes are meaningful for screening and prioritizing interventions in applied settings.

Q: What next steps should a practitioner take after identifying an athlete with limited DF ROM and poor side-bridge performance? A: Create a targeted plan: mobility and soft-tissue work for the ankle, progressive lateral/core strengthening, and a staged landing retraining program that begins with low-height controlled landings and advances to sport-specific reactive jumps. Reassess every 4–8 weeks and progress based on objective improvements and observed landing mechanics.