Natural grass fields carry a lower overall injury rate than artificial turf across most sports studied, though the gap is narrower than many athletes assume and depends heavily on the type of injury, the sport, who is playing, and how well the field is maintained. In NFL data from 2021 and 2022, lower extremity injuries occurred about 16 percent more often on turf, and season-ending surgeries were roughly 60 percent more likely on the synthetic surface. The picture gets more complicated once you look beyond football, factor in heat-related risks and field upkeep, and consider that not all turf fields behave the same way.
How Big Is the Injury Gap in Football
The strongest data on this question comes from American football, which has the largest body of tracked injuries across surface types. A study covering 718 lower extremity injuries in the NFL across the 2021 and 2022 seasons found 1.22 injuries per game on natural grass and 1.42 per game on artificial turf. More striking than the raw count was the severity difference: the odds of an injury requiring season-ending surgery were 60 percent higher on turf, and that elevated risk held up even after accounting for weather, player age, position, and prior injury history.1PubMed Central. Lower Extremity Injury Rates on Artificial Turf Versus Natural Grass Surfaces in the National Football League During the 2021 and 2022 Seasons
An earlier and larger analysis of NFL injury data found a 16 percent overall increase in lower extremity injuries per play on synthetic turf. When researchers narrowed the focus to injuries that caused players to miss eight or more days, the turf disadvantage persisted. The gap widened further for noncontact and surface-contact injuries, the kinds most plausibly linked to what the ground itself does to a player’s foot and leg. For those injury types, rates on turf were 20 to 100 percent higher depending on the specific category.2PubMed. Higher Rates of Lower Extremity Injury on Synthetic Turf Compared With Natural Turf Among National Football League Athletes: Epidemiologic Confirmation of a Biomechanical Hypothesis
ACL Tears and Turf
Anterior cruciate ligament injuries get outsized attention in the grass-versus-turf debate because they end seasons and sometimes careers. A systematic review of the literature found that four studies totaling 753 ACL injuries reported an increased risk on artificial surfaces, and all four involved American football. Those studies included both older-generation turf and modern third-generation surfaces, suggesting the problem is not limited to outdated fields.3PubMed. Risk of Anterior Cruciate Ligament Injury in Athletes on Synthetic Playing Surfaces: A Systematic Review
High school data tells a similar story with some interesting wrinkles. Among all injuries tracked, ACL tears were about 23 percent more likely on turf than grass in high school football, and 53 percent more likely in girls’ soccer. Boys’ soccer showed a trend in the same direction that fell just short of statistical significance at the all-injury level but became significant when the analysis was restricted to lower extremity injuries specifically.4PubMed Central. Epidemiological Comparison of ACL Injuries on Different Playing Surfaces in High School Football and Soccer
Women Face a Larger Risk on Turf
The ACL data reveals a sex-based disparity that deserves its own discussion. A systematic review and meta-analysis of soccer injuries found that female players had a significantly higher ACL injury risk on artificial turf compared with natural grass, while male players did not. The increased risk for women was statistically significant; for men, the trend pointed in the same direction but could not be distinguished from chance.5PubMed Central. Increased Risk of ACL Injury for Female but Not Male Soccer Players on Artificial Turf Versus Natural Grass: A Systematic Review and Meta-Analysis
This disparity likely compounds an already-existing vulnerability. Women in sports tear their ACLs at higher baseline rates than men do, for reasons tied to anatomy, hormones, and neuromuscular patterns. When you layer a surface that increases torsional grip on the foot, the additional rotational stress falls on a joint that was already at relatively higher risk. The result is a disproportionate effect that shows up in the data as a surface-sex interaction. For coaches and administrators making field decisions for women’s and girls’ programs, this is probably the single most important finding in the literature.
Why Turf Grips the Foot Differently
The injury patterns above trace back to a physical property: rotational traction, or how much resistance the surface offers when a planted foot tries to twist. Testing of cleated footwear on various surfaces found that both types of artificial surface produced significantly higher peak torque and rotational stiffness than natural grass.6PubMed. Football playing surface and shoe design affect rotational traction On grass, when you plant and cut, the soil and root structure give way a little, allowing your foot to release. On turf, the synthetic fibers and infill grip the cleat more tightly and resist rotation. That extra grip sounds like it would help performance, but it also means the forces of a sudden direction change travel up the leg to the knee and ankle rather than being absorbed at the foot.
Professional soccer players have articulated this from their own experience, identifying three surface-related risk factors on turf: greater stiffness, greater friction, and a larger metabolic cost to playing on the surface.7PubMed Central. The perceptions of professional soccer players on the risk of injury from competition and training on natural grass and 3rd generation artificial turf The stiffness and friction points align directly with the biomechanical data. The metabolic cost finding is interesting on its own: players report that the surface takes more out of them physically, which could contribute to late-game fatigue and the injury risk that comes with it.
Ankle Sprains and Foot Injuries
Ankles and feet sit closest to the playing surface, so they are the most direct recipients of whatever the surface does. A prospective study of elite football (soccer) found that ankle sprains occurred at a rate of 4.83 per 1,000 match hours on artificial turf compared with 2.66 on grass, nearly double. The authors cautioned that the absolute number of sprains was small, but the direction of the finding matches the broader pattern.8PubMed Central. Risk of injury in elite football played on artificial turf versus natural grass: a prospective two-cohort study
A systematic review that pooled findings across multiple studies confirmed that foot and ankle injuries were the anatomic area most consistently linked to higher rates on turf. This held for both older-generation surfaces and newer third-generation fields, though the proportion of studies finding a significant difference was larger for older surfaces (three out of four) than newer ones (nine out of 19).9PubMed. Lower Extremity Injury Rates on Artificial Turf Versus Natural Grass Playing Surfaces: A Systematic Review That pattern suggests newer turf is better than what came before but still has not fully closed the gap with grass for ankle and foot injuries.
Turf Gets Dangerously Hot
One risk category where artificial turf is unambiguously worse is surface temperature. A systematic review of 13 studies comparing surface temperatures between synthetic and natural grass found that turf consistently ran hotter under all conditions. The numbers are dramatic: third-generation synthetic surfaces averaged around 46°C compared with roughly 24 to 35°C for natural grass, depending on the study. On clear, sunny days, turf could exceed grass temperatures by 25 to 37°C. Even on overcast days, the gap persisted at 14 to 21°C. Technologies marketed as heat-reducing, such as “Cool climate” turf fibers or HydroChill systems, still produced surface temperatures significantly higher than natural grass.10PubMed Central. The effect of synthetic grass sports surfaces on the thermal environment: A systematic review
A field study that measured temperatures over 51 consecutive days found the artificial turf averaged about 50°C during the daytime, compared with roughly 30 to 32°C for natural turf (irrigated and unirrigated). That 50°C average exceeded the 48°C threshold for skin burns for nearly four hours per day. The physics behind this are straightforward: artificial turf has a lower albedo, meaning it absorbs more sunlight, and a lower specific heat capacity, meaning it heats up faster with less energy input.11Building and Environment. The microclimate, surface energy flux and human skin burn risks of artificial turf as compared to natural turf
This matters most for summer practices and for youth sports, where kids are closer to the ground and less able to self-regulate hydration. A field that can literally burn skin on contact for four hours of an average warm day is a meaningful hazard that has nothing to do with biomechanics or cleat grip. If you play or coach on turf during warm months, the heat risk is arguably a bigger concern than the joint injury risk.
Not All Turf Fields Are Equal
Talking about “artificial turf” as a single category obscures real variation. The infill, the fibers used, the age of the installation, and the maintenance schedule all influence how the field plays and how much risk it carries. A study of high school football injuries across turf systems with different infill weights found that fields with heavier infill (6.0 to 9.0+ pounds per square foot) produced significantly fewer total injuries, concussions, surface-impact injuries, and lower extremity injuries compared with lighter-infill systems.12PubMed Central. Incidence, Mechanisms, and Severity of Game-Related High School Football Injuries Across Artificial Turf Systems of Various Infill Weights The heavier infill likely provides better shock absorption and more stable footing, reducing both the hardness of the surface and the rotational forces on the foot.
Field age is another factor that tends to get overlooked. As turf fields age, infill compacts and thins out, leading to an increase in surface hardness and growing variability from spot to spot across the field. That means an older turf field might have unpredictable patches that are significantly harder than others, creating an inconsistent playing surface even within a single game.13Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology. Impact of third generation synthetic turf athletic field age on surface hardness and infill depth spatial variability Regular maintenance, including infill top-ups and decompaction, can counteract this aging process, but many fields, particularly at the school and recreational level, do not get the maintenance they need. Infill depth should be kept to manufacturer specifications and monitored routinely.14PubMed Central. Synthetic Turf: History, Design, Maintenance, and Athlete Safety
The practical upshot is that a well-maintained, newer turf field with appropriate infill weight is substantially safer than a neglected, aging one. Some of the injury data in the literature may reflect poorly maintained fields dragging up the averages for turf as a category.
Muscle Soreness and Recovery
Beyond acute injury, athletes consistently report that playing on turf takes more out of them physically. A study of elite rugby union players measured muscle soreness over four days following matches on each surface. Players who normally trained on grass reported consistently higher soreness after playing on artificial turf, though the magnitude of the effect was small.15PubMed. The influence of an artificial playing surface on injury risk and perceptions of muscle soreness in elite Rugby Union
Interestingly, when researchers measured actual physical performance after a soccer-specific exercise simulation on both surfaces, they found no significant difference in metrics like countermovement jump height or in subjective ratings.16PubMed. Physical performance and subjective ratings after a soccer-specific exercise simulation: comparison of natural grass versus artificial turf This creates a bit of a disconnect: players feel worse on turf, but the measurable performance drop is hard to detect in controlled settings. The soreness finding may reflect the cumulative impact of a harder, higher-friction surface over a full match, something that a simulation can miss but a real game captures. It may also be partly psychological, since players know they are on turf and expect to feel worse. Either way, the subjective experience matters for scheduling, training load management, and player willingness to compete.
Young Athletes and Prolonged Exposure
Most large-scale injury comparisons come from professional or college-level sports, but youth athletes spend far more cumulative hours on playing surfaces. A study of adolescent soccer players found that the overall injury incidence was similar between turf and grass groups, but one finding stood out: players training on artificial turf had a 62 percent higher rate of low back pain. Early adolescence and prolonged training hours were associated with increased chronic pain in the turf group. The authors recommended careful monitoring of young players who routinely train on artificial turf for extended periods, even on surfaces meeting current standards.17Clinical Journal of Sport Medicine. Incidence of Injury Among Adolescent Soccer Players: A Comparative Study of Artificial and Natural Grass Turfs
The low back pain finding gets at something the acute injury data misses. Young bodies are still developing, and the stiffer, less forgiving surface of turf transmits more impact force with every stride and landing. Over thousands of repetitions across a training season, that additional loading could contribute to overuse problems that would never show up in a study counting game-day injuries.
Infection Risk From Turf Burns
Anyone who has played on turf knows the distinctive abrasion it leaves, the so-called “turf burn.” Beyond the cosmetic annoyance, these open skin wounds create a pathway for bacterial infection, including antibiotic-resistant bacteria. A laboratory study examined how long methicillin-resistant Staphylococcus aureus (MRSA) could survive on various turf components. On infill materials, MRSA remained viable for up to 96 hours, with the time to 50 percent die-off averaging 13 hours. On turf fibers themselves, the bacteria survived for up to 24 hours, with a 50 percent die-off time of about four hours. Survival varied by material: sand-based infill kept MRSA alive longest (27 hours to 50 percent die-off), while EPDM rubber killed off bacteria most quickly (two hours).18PubMed Central. The Fate of Methicillin-Resistant Staphylococcus aureus in a Synthetic Turf System
Natural grass fields are not sterile either, of course, and soil contains its own microbial communities. But turf burns are more common and more extensive on artificial surfaces because the synthetic fibers act like fine sandpaper against skin during slides and falls. The combination of more frequent abrasions and a surface that can harbor bacteria for hours creates a genuine infection risk, especially in contact sports where multiple players share the field throughout a day.
Chemicals in Crumb Rubber
Crumb rubber infill, made from recycled tires, has raised concerns about chemical exposure for years, particularly for athletes who spend a lot of time on their hands and knees or who accidentally ingest small particles. A comprehensive human health risk assessment evaluated multiple exposure pathways, including inhalation, skin contact, and ingestion of crumb rubber material. The estimated cancer risks and non-cancer hazards for all scenarios fell within EPA guidelines. Cancer risk levels for turf field users were comparable to or lower than those associated with natural soil fields.19PubMed. Comprehensive multipathway risk assessment of chemicals associated with recycled (“crumb”) rubber in synthetic turf fields
However, two areas of ongoing concern remain. Laboratory studies using animal models have shown that concentrated crumb rubber leachate can disrupt thyroid hormone signaling, suggesting a potential endocrine mechanism worth tracking even if real-world exposure levels appear safe.20PubMed Central. Health Impacts of Artificial Turf: Toxicity Studies, Challenges, and Future Directions And turf components contain detectable levels of certain PFAS compounds, specifically fluorotelomer alcohols. Testing found 8:2 FTOH at roughly 300 nanograms per gram in turf fibers and 110 nanograms per gram in crumb rubber.21Case Studies in Chemical and Environmental Engineering. Assessing extraction-analysis methodology to detect fluorotelomer alcohols (FTOH), a class of perfluoroalkyl and polyfluoroalkyl substances (PFAS), in artificial turf fibers and crumb rubber infill Whether those levels translate to meaningful human exposure through normal play is still an open question. The risk assessments completed so far are reassuring, but they were conducted before PFAS contamination was widely recognized as a concern, and the field is evolving.
When Turf Makes Practical Sense Anyway
Given everything above, you might wonder why anyone installs artificial turf. The answer is that natural grass has its own serious limitations, particularly in climates with harsh winters, in regions with water restrictions, and at facilities that see heavy use. A grass field that gets played on six or seven days a week quickly turns into a muddy, divot-ridden surface that carries its own injury risks, especially around the goal mouth in soccer or in the trenches in football. A waterlogged or frozen grass field is not safer than a well-maintained turf field. Many schools and municipalities simply cannot afford the irrigation, mowing, fertilizing, and rest periods that high-quality grass requires. Turf fills that gap by providing a consistent, all-weather surface that handles thousands of hours of use per year.
The real comparison, then, is often not between turf and pristine natural grass. It is between turf and whatever grass field the institution can actually maintain. A beautifully kept bermuda or bluegrass field at a professional stadium is probably the safest playing surface available. A neglected, overused grass field with bare patches and uneven footing might not outperform even an average turf installation. The question for any given community is which surface they can realistically keep in good condition given their budget, climate, and usage demands.
Choosing Footwear for Each Surface
One variable within your control, regardless of which surface you are stuck playing on, is your shoes. The rotational traction research makes it clear that the interaction between cleat design and surface type matters for injury risk. Longer, bladed studs designed for soft natural grass generate excessive grip on turf and exaggerate the rotational forces on the knee and ankle. Turf-specific shoes with shorter, more numerous rubber studs or nubs distribute force more evenly and allow more natural foot rotation during cutting and pivoting. Many youth leagues and recreational programs do not specify footwear by surface type, which means players often wear the same molded cleats on turf that they would on grass. That mismatch is a correctable risk factor. If you or your child plays on turf regularly, using shoes designed for that surface is one of the simplest ways to reduce the chance of a noncontact lower extremity injury.