Influence of the structural components of artificial turf systems on impact attenuation in amateur football players

Abstract

The purpose of this research was to evaluate the influence of the structural components of different 3rd generation artificial turf football field systems on the biomechanical response of impact attenuation in amateur football players. A total of 12 amateur football players (24.3 ± 3.7 years, 73.5 ± 5.5 kg, 178.3 ± 4.1 cm and 13.7 ± 4.3 years of sport experience) were evaluated on three third generation artificial turf systems (ATS) with different structural components. ATS were composed of asphalt sub-base and 45 mm of fibre height with (ATS1) and without (ATS2) elastic layer or compacted granular sub-base, 60 mm of fibre height without elastic layer (ATS3). Two triaxial accelerometers were firmly taped to the forehead and the distal end of the right tibia of each individual. The results reveal a higher force reduction on ATS3 in comparison to ATS1 (+6.24%, CI95%: 1.67 to 10.92, ES: 1.07; p < 0.05) and ATS2 (+21.08%, CI95%: 16.51 to 25.66, ES: 2.98; p < 0.05) elastic layer. Tibia acceleration rate was lower on ATS3 than ATS1 (−0.32, CI95%: −0.60 to −0.03, ES: 4.23; p < 0.05) and ATS2 (−0.35, CI95%: −0.64 to −0.06; ES: 4.69; p < 0.05) at 3.3 m/s. A very large correlation ( r = 0.7 to 0.9; p < 0.05) was found between energy restitution and fibre height in both head and tibial peak acceleration and stride time. In conclusion, structural components (fibre height, infill, sub-base and elastic layer) determine the mechanical properties of artificial turf fields. A higher force reduction and lower energy restitution diminished the impact received by the player which could protect against injuries associated with impacts compared to harder artificial turf surfaces.

A Proposed Method to Assess the Mechanical Properties of Treadmill Surfaces

“…Sassi et al [8] previously reported that an increase in SA of the surface in question is the main mechanical property responsible for a reduction in elastic energy recovery and in overall muscle-tendon efficiency, thereby resulting in greater muscle work and higher energy demands. Although they did not actually use a treadmill, these authors estimated that an increase in SA of approximately 35% will result in an increase in the cost of running of 5%, complementing previous findings that the mechanical behavior of the surface affects muscle force generation and running economy [32][33][34][35], and supporting those who later reported varying injury risk and effort perception [36,37]. In addition, in a systematic review Miller et al [38] found that endurance running performance is generally poorer on a motorized treadmill compared to overground, which could partly be related to differences in surface stiffness.…”

Impact Deceleration Differences on Natural Grass Versus Synthetic Turf High School Football Fields

“…16 The composition, turf thickness, and material underlying the synthetic turf layer can also have significant effects on its hardness. 20 The infill used to mimic soil in synthetic turf installations, often referred to as crumb rubber, alter the impact of falling onto the turf. One study identified decreased infill density as a risk factor for football injuries.…”

“…6 Well-maintained synthetic turf fields can perform similarly to natural grass fields, but a multitude of factors such as weather and infill compaction with use can cause deterioration of their protective effects. 19,20 These factors may be exacerbated in high school sports, where field maintenance resources may be less available or of lower quality than those of professional sports stadiums. It has been suggested by research on athletes of many levels, from high school to professional American football, that these differential injury rates may result from differential surface hardness.…”