White Paper 06 — NFL-Level Expectations for Synthetic Turf Systems

What professional-level performance standards actually measure — and what any field owner can learn from them.

“NFL-level turf” is often used as shorthand for the highest quality bar available in synthetic turf — but it isn’t a single credential a manufacturer either holds or doesn’t. It’s a set of specific, measurable performance properties, evaluated through defined testing methods that continue to evolve as the league and players’ association refine what they measure.

This paper covers the current state of NFL playing surface standards, the core performance metrics behind any professional-grade system, what NFL players themselves say about turf versus grass, and what field owners outside the NFL can practically take from all of it.

The NFL and NFLPA Are Actively Raising the Bar

In December 2025, the NFL and the NFL Players Association’s Joint Field Surface Safety and Performance Committee introduced new mandatory playing surface standards, applying to both synthetic and natural grass fields. The standards evaluate surfaces using two purpose-built testing tools: the BEAST (Biomechanical Elite Athlete Shoe-Turf Tester), which simulates player movement to assess traction and rotational behavior, and the STRIKE Impact Tester, which measures how much energy a surface absorbs on contact.

Systems are tested against a target range informed by natural grass performance data, with the explicit goal of improving consistency across every NFL field — grass, synthetic, or hybrid. All 32 teams will be required to use an approved surface by the 2028 season. This is a significant, active shift in how the league defines field quality, reflecting years of player feedback about inconsistent surface performance across venues.

The Core Performance Metrics Behind Any NFL-Level System

Regardless of which specific testing program a field is evaluated under, the underlying properties that separate a professional-grade turf system from a basic one are consistent:

• Traction and rotational resistance — how predictably the surface releases a cleat during cutting and pivoting movements. Too little release increases lower-extremity injury risk; too much reduces performance.
• Impact attenuation (force reduction and Head Injury Criterion) — how much energy the surface absorbs versus returns to the body on contact, whether from a fall, tackle, or footstrike.
• Surface consistency (Gmax and vertical deformation) — how uniform the surface plays across the entire field, not just at a single test point.
• Infill consistency — even distribution and depth of infill across the field, which directly affects how uniformly the surface performs from one location to the next.

Act Global approach: We test every system against these categories through independent labs, including Firefly Sports Testing, Labosport, and Sports Labs — the same accredited testing infrastructure referenced throughout our Research Library.

What Players Actually Say — and Why It Matters

Any honest discussion of NFL-level turf has to include the NFLPA’s own player survey data: in the union’s most recent membership survey of roughly 1,700 professional players, 92% said they prefer playing on high-quality natural grass, with only 2% preferring synthetic turf.

We think that number reflects a preference and comfort metric, not a direct injury-rate metric, and it points to real, historical inconsistency in how synthetic turf has been built and maintained across the league — not proof that a well-engineered synthetic system can’t close that gap. It’s also exactly the kind of data point a serious turf manufacturer should engage with directly rather than avoid. Full detail in our companion article, What the NFLPA Survey Results Really Mean for Field Safety.

What This Means for Fields Outside the NFL

Most organizations building a field aren’t installing an NFL stadium surface, but the same underlying categories apply at any level: traction consistency, impact attenuation, surface uniformity, and infill consistency are what separate a well-engineered system from a generic one, whether it’s a high school stadium or a professional practice facility.

Field owners evaluating a synthetic turf project should ask for independent test data in these specific categories — not just a general safety claim — regardless of which manufacturer they’re considering. The specific certification program a field is evaluated under matters less than whether rigorous, independent, and current data exists for the categories that actually determine performance and safety.

Conclusion

NFL-level performance standards are a moving target, evolving as testing technology and player feedback improve — which is exactly why “NFL-level” should be understood as a bar defined by specific, current, independently verified metrics, not a static label. The categories that matter — traction, impact attenuation, consistency, and infill uniformity — are the same ones that should guide any serious synthetic turf specification, professional or not.

Frequently Asked Questions

Is there an official “NFL-certified” turf program?

As of December 2025, the NFL and NFLPA introduced new mandatory playing surface standards evaluated by a Joint Field Surface Safety and Performance Committee, using dedicated traction (BEAST) and impact (STRIKE) testing tools. All NFL stadiums and practice facilities must use an approved surface by the 2028 season.

Do NFL players prefer grass or turf?

In the NFLPA’s most recent survey of approximately 1,700 players, 92% said they prefer natural grass, 6% were indifferent, and 2% preferred synthetic turf.

What should a non-NFL field owner look for if they want “NFL-level” quality?

Independent test data on traction/rotational resistance, impact attenuation (Gmax, HIC, force reduction), surface consistency, and infill consistency — the same underlying categories the NFL evaluates, regardless of the specific certification program involved.

Related Resources

• What Makes a Turf System Suitable for NFL Use?
• White Paper 01 — Synthetic Turf Safety & Performance: A Science-Based Framework
• Rotational Resistance Explained — Traction and Lower-Extremity Injury Risk

Bringing Science to the Surface™ — Act Global

White Paper 02 – Player-Surface Interaction: How Modern Turf Supports Athlete Movement

How footing, traction, energy return, and surface consistency shape performance – and what field owners should specify for their sport.

Most conversations about synthetic turf focus on injury prevention. This white paper focuses on the other half of the equation: performance. How a surface supports,  or works against, an athlete’s movement affects footing stability, energy expenditure, ball behavior, and ultimately how a game is played.

This paper covers four performance domains: stable footing and traction, energy return and fatigue, ball behavior and surface consistency, and how these priorities shift depending on the sport being played. As with our companion safety framework, every claim here is tied to a specific, testable property, not a general performance claim.

Stable Footing and Traction

Athletic performance depends on a surface behaving predictably under load, during acceleration, deceleration, and directional change. Two properties govern this: rotational resistance (how much a cleat grips and releases) and vertical deformation (how consistently the surface supports weight across its full area).

A surface with too little traction increases slip risk and undermines an athlete’s ability to accelerate or change direction with confidence. A surface with too much resistance can restrict natural pivoting motion, which is directly implicated in several injury mechanisms documented in Act Global’s Research Library. The performance target is not maximum grip, it’s a specific, tested range that supports both control and safe release.

Act Global approach: We test and publish rotational resistance data for every system, and specify fiber and infill design to hit a traction range appropriate to the sport and level of play, not a single generic target across all applications.

Energy Return and Fatigue

Energy restitution, how much of an athlete’s energy a surface returns versus absorbs, has a real, measurable effect on perceived exertion and fatigue accumulation over the course of a match or training session. A surface that absorbs too much energy can make the same physical effort feel more demanding, while a surface that’s too reactive can reduce the fine control needed for precise movement.

Independent research adds a useful data point here: our review of a 2019 repeated-sprint study found lower blood lactate, lower perceived exertion, and less fatigue-related performance drop-off on artificial turf compared to natural grass in the specific protocol tested,though the researchers themselves note this was a small study, and the broader literature on sprint performance by surface remains genuinely mixed. We think it’s worth citing that honestly rather than overstating a single small study as settled science.

Act Global approach: We balance energy restitution against impact attenuation deliberately in system desig,the two properties trade off against each other, and neither should be optimized in isolation.

Ball Behavior and Surface Consistency

For ball-based sports, surface consistency directly affects predictability of ball roll, bounce, and speed, properties governed largely by pile height, infill depth, and vertical deformation uniformity across the field. Inconsistent infill distribution, common in aging or poorly maintained systems, creates unpredictable ball behavior in exactly the same high-traffic zones where footing consistency also degrades.

This is the same underlying theme covered in our Safety & Performance Framework white paper: a single installation-day test doesn’t guarantee consistent performance over a field’s lifecycle. Ball behavior consistency is a maintenance question as much as a design question.

Act Global approach: We test vertical deformation and infill depth at multiple points across every field, not a single location, because that’s the actual determinant of consistent ball behavior across the full playing surface, not just at midfield.

Sport-Specific Performance Needs

Different sports place different demands on the same underlying properties:

• Football and rugby prioritize traction for acceleration and controlled release during tackles and cuts, alongside impact attenuation for frequent ground contact.
• Soccer prioritizes consistent ball roll and bounce alongside traction for pivoting and change-of-direction movement.
• Field hockey requires a lower-pile, tightly consistent surface optimized for ball speed and true roll, with different infill and fiber specifications than football-oriented systems.
• Multi-use community and school fields require a balanced specification that performs adequately across several sports, rather than being optimized for a single one.

A system specified without accounting for its primary sport and usage pattern is unlikely to perform optimally, regardless of how strong its individual test numbers look in isolation.

Act Global approach: We specify fiber height, infill type, and construction per project based on the sport and usage pattern the field will actually see — not a single universal system applied everywhere.

Conclusion

Performance and safety are not separate conversations, they’re governed by the same underlying properties, tested the same way, and specified together. A field engineered for stable footing, appropriate energy return, and ball consistency is, by definition, also being engineered against the injury mechanisms covered in our companion safety framework.

We’d encourage any organization specifying a synthetic turf system to ask not just “is this surface safe,” but “is this surface specified correctly for the sport and athletes who will actually play on it.”

Frequently Asked Questions

What surface properties affect athletic performance on turf?

Rotational resistance (traction), energy restitution (fatigue/energy return), and vertical deformation (surface consistency) are the primary properties governing how a surface supports athletic movement.

Does synthetic turf reduce fatigue compared to natural grass?

Some research suggests lower perceived exertion and fatigue markers on synthetic turf in specific test protocols, but the broader research on this question is mixed and should not be treated as settled.

Should turf specification differ by sport?

Yes. Football, soccer, rugby, and field hockey each place different demands on traction, ball behavior, and impact properties, and system specification should reflect the field’s primary use.

Related Resources

• White Paper 01 — Synthetic Turf Safety & Performance: A Science-Based Framework
• Physical, Physiological, and Perceptual Responses to Sprint Testing — Review of Ammar et al. 2019
• Synthetic Turf vs. Natural Grass — Why Consistency Matters More

Bringing Science to the Surface™, Act Global

White Paper 01 – Synthetic Turf Safety & Performance: A Science-Based Framework

The measurable properties that define a professional-grade synthetic turf system — and how to verify them independently.

“Safe” and “high-performing” aren’t marketing adjectives at Act Global, they’re measurable outcomes, defined by a specific set of testable properties and verified through independent laboratory and field testing. This white paper lays out the complete framework: the ten core metrics that define synthetic turf safety and performance, what each one actually measures, why it matters to athletes and field owners, and how Act Global approaches specification and testing for each.

It’s written for the people responsible for making a real specification decision, architects, engineers, athletic directors, and facility planners, who need substance, not superlatives. Every claim is tied to a named standard or test method.

What’s Inside

The ten metrics covered in this paper fall into three practical categories:

• Impact & Injury Attenuation. g-max, Head Injury Criterion (HIC), and Force Reduction
• Movement & Traction. Rotational Resistance, Energy Restitution, and Vertical Deformation
• System Durability & Consistency Over Time. Infill Weight & Specification, Maintenance Cadence, Field Age, and Lifecycle Consistency

Our Approach: Bringing Science to the Surface™

Every metric in this paper is governed by a published testing standard, most commonly maintained by ASTM International Committee F08 on Sports Equipment, Playing Surfaces, and Facilities. Act Global tests every system against these standards through independent, accredited labs, including Firefly Sports Testing, Labosport, and Sports Labs, not internal, self-reported results.

We also believe testing shouldn’t stop at installation. A system that performs perfectly on day one can still degrade unevenly without proper maintenance and periodic re-testing. This paper treats performance as a lifecycle question throughout, not a single installation-day snapshot.

Part I – Impact & Injury Attenuation

g-max, Surface Hardness and Impact Attenuation

Governed by ASTM F1936 (Standard Specification for Impact Attenuation of Turf Playing Systems as Measured in the Field).

Gmax measures how much shock a surface absorbs versus transmits back to the body during impact, expressed as a multiple of gravitational acceleration (g). Lower g-max values indicate a softer, more shock-absorbing surface; excessively high values are associated with increased injury risk on impact.

Gmax is one of the most direct, field-testable indicators of impact safety, and it’s sensitive to installation quality, infill depth, and shock pad specification, not just the turf fibers themselves.

Act Global approach: Every system is tested for Gmax both at installation and on a defined re-testing schedule, since infill compaction over time can gradually raise Gmax beyond its original tested value.

Head Injury Criterion (HIC)

A biomechanical injury metric used across sports surface and equipment testing to model head impact severity.

HIC estimates the likelihood and severity of head injury from an impact, based on the acceleration profile experienced during a simulated fall or collision with the surface. It is a more specific, head-injury-focused complement to Gmax.

Because head impacts carry disproportionate long-term health consequences, HIC performance is treated as a first-tier safety metric, not a secondary consideration behind general shock absorption.

Act Global approach: HIC testing is part of our standard system evaluation, particularly for football, rugby, and other contact-sport applications where head-to-surface contact is a realistic scenario.

Force Reduction

A companion measurement to Gmax, often reported together under the same field and lab test protocols.

Force reduction quantifies the percentage of impact force a surface absorbs compared to a rigid, non-shock-absorbing reference surface (typically concrete). Higher force reduction means more of the impact energy is absorbed by the system rather than transmitted to the athlete’s body.

This metric is especially relevant for repetitive lower-body impact, running, jumping, and landing, rather than single high-energy impacts alone.

Act Global approach: Force reduction data is included in every independent test report, alongside Gmax, so field owners see the complete impact-attenuation picture rather than a single isolated number.

Part II , Movement & Traction

Rotational Resistance, Traction and Release

Evaluated using purpose-built rotational traction testing devices, referenced within ASTM F1551 (Standard Test Methods for Comprehensive Characterization of Synthetic Turf Playing Surfaces).

Rotational resistance measures how much a cleat grips the surface, and, just as importantly, how readily it releases during pivoting and cutting movements. Too little traction increases slip risk; too much resistance is directly implicated in non-contact lower-extremity injury mechanisms, including several documented in Act Global’s Research Library.

This is one of the most engineerable, and most safety-relevant, properties of a turf system, a function of fiber design, infill type, and system construction, not an inherent, fixed property of “synthetic turf” as a category.

Act Global approach: We publish rotational resistance data for every system and treat it as a specification-stage conversation, particularly for sports and athlete populations where the research has flagged elevated risk on certain historical turf generations.

Energy Restitution

Measured as part of comprehensive field performance testing, often alongside g-max and force reduction protocols.

Energy restitution describes how much of an athlete’s energy is returned by the surface versus absorbed, directly affecting perceived speed, fatigue accumulation, and overall playability over the course of a match or practice.

A system with poor energy restitution can measurably increase athlete fatigue over a game or training session, independent of any single-impact injury risk.

Act Global approach: We evaluate energy restitution as part of our broader performance testing, balancing it against impact attenuation, the two properties trade off against each other, and system design has to manage that balance deliberately.

Vertical Deformation, Surface Stability and Foot Support

Evaluated under ASTM F1551 comprehensive characterization test methods.

Vertical deformation measures how much a surface compresses under load and how consistently it returns to its original shape. Excessive or uneven deformation affects foot stability, ball behavior, and long-term surface consistency.

This metric is particularly sensitive to consistency across a field, a system that performs well at a single test point but deforms unevenly across high-traffic zones creates exactly the kind of unpredictable footing associated with increased injury risk.

Act Global approach: We test vertical deformation at multiple points across each field, not a single location, because uniformity across the entire playing surface is the practical safety question field owners actually care about.

Part III – System Durability & Lifecycle Consistency

Infill Weight & Specification

Infill type and depth are specified per system design and verified through field testing and submittal documentation.

Infill provides the weight, cushioning, and fiber support that underlie nearly every other metric in this paper. Infill category (rubber, TPE, organic, coated) and weight/depth directly influence Gmax, rotational resistance, and vertical deformation performance, and heavier infill specifications have been associated with measurably lower injury severity in peer-reviewed research.

Infill is not a one-size-fits-all decision, climate, sport, usage volume, and budget all factor into the right specification for a given field.

Act Global approach: We specify infill type and weight per project based on documented performance data. See our full breakdown in Infill Options & Environmental Considerations.

Maintenance Cadence

Maintenance requirements are specified per system and should be documented in writing at time of purchase, not treated as a general recommendation.

A system that tests perfectly at installation can still degrade in performance and safety over time without a defined maintenance program, grooming, infill redistribution, decompaction, and drainage checks all directly affect the metrics covered throughout this paper.

Neglected maintenance doesn’t just shorten a field’s usable life, it measurably changes g-max, rotational resistance, and vertical deformation, the same properties that defined the field’s safety performance at installation.

Act Global approach: We provide a written, usage-scaled maintenance plan with every installation. Full detail in Maintenance, Lifecycle Consistency & Field Safety Over Time.

Field Age & Performance Degradation

Tracked through periodic re-testing against the system’s original installation-day baseline.

All synthetic turf systems change over time, fiber matting, infill compaction, and UV exposure gradually shift performance metrics away from their installation-day baseline. The rate of that change depends heavily on usage volume, climate, and maintenance quality.

A field’s age alone doesn’t determine whether it’s still safe to play on, its most recent test data does. This is why installation-day certification alone is an incomplete safety picture for any field beyond its first season.

Act Global approach: We build a defined re-testing schedule into every system’s lifecycle plan, so performance data, not assumptions based on age, drives replacement and renovation decisions.

Lifecycle Consistency

An integrating principle across every metric in this paper, rather than a single standalone test.

The central theme of this white paper is that no single test result, taken in isolation, defines whether a field is safe or high-performing. Consistency, across the field, and across the system’s lifecycle, is what determines real-world outcomes for athletes.

Natural grass and synthetic turf both face consistency challenges, just from different sources: grass from weather, wear, and season; synthetic turf from infill migration, compaction, and maintenance quality. A well-specified, well-maintained synthetic system is designed specifically to solve the consistency problem grass cannot fully control. See our full discussion in Synthetic Turf vs. Natural Grass — Why Consistency Matters More.

Act Global approach: We evaluate and report on every metric in this paper together, as an integrated system, not as isolated marketing claims.

Conclusion: An Integrated Framework, Not a Single Claim

No single number on this list, by itself, makes a turf system safe or unsafe, high-performing or low-performing. Gmax without rotational resistance data is an incomplete safety picture. Installation-day testing without a maintenance and re-testing plan is a snapshot, not a guarantee. The value of this framework is in treating all ten metrics as connected parts of one system — because that’s how they actually behave on a real field, under real athletes, over a real lifecycle.

This is the standard Act Global holds every system to, and the standard we’d encourage any organization evaluating a synthetic turf project to hold every manufacturer to, not general safety claims, but specific, independently verified, lifecycle-aware performance data.

Frequently Asked Questions

What metrics determine if synthetic turf is safe?

Ten core metrics, evaluated together: Gmax, Head Injury Criterion (HIC), Force Reduction, Rotational Resistance, Energy Restitution, Vertical Deformation, Infill Weight & Specification, Maintenance Cadence, Field Age, and Lifecycle Consistency.

What ASTM standards govern synthetic turf testing?

Key standards include ASTM F1936 (g-max/impact attenuation) and ASTM F1551 (comprehensive characterization test methods), maintained by ASTM Committee F08 on Sports Equipment, Playing Surfaces, and Facilities.

Does installation-day testing guarantee long-term field safety?

No. Performance properties change over a field’s lifecycle due to infill compaction, fiber wear, and maintenance quality. Periodic re-testing against the original baseline is necessary to confirm ongoing safety performance.

Who is independently testing Act Global’s systems?

Firefly Sports Testing, Labosport, and Sports Labs, accredited, independent labs, not internal or self-reported results.

Related Resources

• Infill Options & Environmental Considerations
• Maintenance, Lifecycle Consistency & Field Safety Over Time
• Synthetic Turf vs. Natural Grass — Why Consistency Matters More
• Full Research Library

Bringing Science to the Surface™, Act Global