Return To Sport Battery Testing: Using VALD Force Decks

Jess Mcdonald
Apr 17
4 min read

A Structured, Objective Approach for Athletes and Clinicians

Jessica McDonald

Senior Physiotherapist – MOVE Sports Physiotherapy & Pilates Geelong

Returning an athlete to sport is one of the most critical — and high-risk — decisions in rehabilitation. While pain reduction and basic function are important milestones, they do not adequately reflect an athlete’s readiness for the demands of sport.

A well-designed Return-to-Sport (RTS) battery provides a structured, objective framework to guide this decision-making process. Positioned at the end of the performance phase, it acts as the final “gatekeeper” before discharge — ensuring the athlete is not only recovered, but resilient, prepared, and capable of performing at a high level.

For clinicians working in performance settings, particularly those using technologies such as VALD Performance systems, RTS testing offers a powerful opportunity to quantify progress and reduce re-injury risk.

Why Return-to-Sport Testing Matters

Research consistently shows that returning to sport without meeting objective criteria significantly increases the risk of re-injury — particularly following injuries such as ACL reconstruction.

Seminal work from researchers such as; Paterno et al., 2010; Grindem et al., 2016; Ardern et al., 2016 has demonstrated that:

Time alone is not enough to determine readiness
Strength and functional symmetry are key predictors of successful return
Psychological readiness plays a critical role in outcomes

The RTS battery brings these domains together into one comprehensive framework.

Core Components of a Return-to-Sport Battery

A high-quality RTS battery should assess multiple domains of performance, ensuring the athlete meets minimum standards across strength, power, control, and confidence.

1. Time-Based Criteria

Time remains an important baseline consideration, particularly for tissue healing.

For ACL reconstruction, a minimum of 9 months post-surgery is widely supported in the literature
Time should always be combined with objective testing — not used in isolation

2. Strength Symmetry

Restoring strength between limbs is fundamental.

Isometric knee extension and flexion should reach ≥90% Limb Symmetry Index (LSI)
Measured via isokinetic dynamometry, handheld dynamometry, or systems such as DynaMo, VALD ForceDecks or ForceFrame

This benchmark is strongly associated with reduced re-injury risk.

3. Hop Testing

Hop tests assess dynamic strength, control, and confidence.

Key tests include:

Single-leg hop for distance
Triple hop
Crossover hop
6-metre timed hop

Criteria: ≥90% LSI across all tests

These tests remain a cornerstone of RTS decision-making, due to their strong functional relevance.

4. Jump Performance

VALD Performance analysis provides deeper insight into movement quality and power.

Using systems like ForceDecks, clinicians can assess:

Countermovement jump (CMJ)
Single-leg CMJ
Peak power output
Reactive Strength Index (RSI-modified)
Inter-limb asymmetry

Criteria:

Asymmetry <10%
Efficient force production and absorption strategies

5. Rate of Force Development (RFD)

Sport often demands rapid force production — not just maximal strength.

Assessments such as:

Isometric mid-thigh pull (IMTP)
Isometric squat

Provide insight into:

Peak force
Explosive strength (RFD)

This is particularly relevant for cutting, sprinting, and change-of-direction tasks.

6. Hamstring Strength

Eccentric hamstring strength is critical for both performance and injury prevention.

Assessed using devices like NordBord
Focus on eccentric output and between-limb symmetry

Criteria:

<10% asymmetry
Meeting normative strength benchmarks

Research led by Opar et al., 2013 highlights the importance of eccentric strength in reducing hamstring injury risk.

7. Groin Strength

For athletes involved in running, kicking, or change-of-direction sports, groin strength is essential.

Measured via isometric adduction and abduction testing
Typically assessed using ForceFrame

Criteria:

Adductor-to-abductor strength ratio ≥0.9

This benchmark, supported by work from Emil Thorborg et al., 2014, is particularly relevant in field and court sports.

8. Psychological Readiness

Physical readiness does not guarantee confidence.

The ACL-Return to Sport after Injury (ACL-RSI) scale is commonly used to assess:

Confidence
Fear of reinjury
Emotional readiness

Criteria:

Score ≥65 for ACL populations

Athletes who are physically ready but psychologically hesitant are at significantly higher risk of suboptimal performance and reinjury.

9. Sport-Specific Task Completion

Finally, athletes must demonstrate the ability to perform sport-specific tasks under realistic conditions.

This includes:

Movement quality under fatigue
Change-of-direction mechanics
Reactive and unpredictable scenarios

This stage bridges the gap between clinical testing and real-world performance.

Integrating VALD Technology into RTS Testing

For clinics equipped with VALD systems, RTS testing becomes both highly objective and highly repeatable.

Exercise Physiologist showing client VALD Performance results at Move Sports Physio Geelong

Key tools include:

ForceDecks: Jump testing, CMJ, single-leg CMJ, IMTP, sit-to-stand
ForceFrame: Isometric strength testing (hip, knee, groin, shoulder)
NordBord: Eccentric hamstring strength
DynaMo: Portable handheld dynamometry for targeted assessments

These systems allow clinicians to:

Track progress over time
Identify asymmetries and deficits
Compare results to normative data
Make evidence-based decisions

Tracking Progress Across the Rehabilitation Journey

A structured RTS protocol should include multiple testing points:

Baseline (Session 1): Establish initial deficits
Midpoint (e.g., Session 6): Monitor progress and adjust programming
Final RTS Testing: Determine readiness for return

Importantly, changes between testing sessions should exceed the smallest detectable difference (SDD) for each metric. This ensures improvements are real and not due to measurement variability.