Sports Turf Research Focusing on Athlete Performance & Safety J.C. SOROCHAN O VERVIEW O F THE UT CEN TER FO R ATHLETIC FIELD SAFETY John Sorochan, Ph.D. January 18, 2018 University of Tennessee Center for Athletic Field Safety CAFS Facts 25 current sports turf research projects 5+ acres of athletic turf research Cool- and warm-season turf and synthetic surfaces Importance Youth injuries (<14) cost the US public $49,192,781,832 in 1997 Emergency room visits (2004) 116,000 baseball 186,000 football AAP, US CPSC, & National Youth Sports Safety Foundation Importance 5.7% of high school football injuries were definitely related to field conditions, 15.2% were possibly related to field conditions (Harper et al., 1984) 10% of lawsuits related to sports injuries claim that the athletic field was inadequately maintained (Dougherty, 1988) 38 million children & adolescents Importance 3.5 million children under 14 receive medical treatment for sports injuries 50% of these injuries are preventable (NIH, 2009) (Safe Kids, 2007) (Brenner, 2007; Safe Kids, 2007) 1
CAFS Traffic Simulator CAFS Traffic Simulator FIFA Soccer Cleat World Rugby Cleat CAFS Traffic Simulator Spring Specification Type: die spring Material: steel Inner diameter: 0.5 in Outer diameter: 1 in Length: 3 in Rating: 10.3 lb per 0.10 in Testing Evaluations Testing Evaluations 2
Testing Methods for Surface Hardness Clegg Surface Hardness Comparisons (ASTM F1702) 2.25 kg (5 lb) missile 45 cm (18 ) drop height ASTM F 355A ASTM F1702 ASTM F355A Synthetic Turf Standard (ASTM 1936) Clegg Surface Hardness Comparisons (ASTM F1702) 9.1 kg (20 lbs) flat missile 61 cm (24 ) drop height Flat surface on projectile 2.25 kg (5 lb) missile 45 cm (18 ) drop height Used to measure high level body impacts F355 Comparisons F355 Comparisons Synthetic Turf = Bermudagrass > Kentucky bluegrass Synthetic Turf vs. Bermudagrass Not different Synthetic Turf 108 GMAX and Bermudagrass 110.5 GMAX Synthetic Turf vs. KBG ***Different Synthetic Turf 108 GMAX and KBG 90 GMAX 9.1 kg missile 61 cm drop height 3
Clegg Surface Hardness Comparisons Bermudagrass > Synthetic Turf > Kentucky bluegrass Clegg Surface Hardness Comparisons Synthetic Turf vs. Bermudagrass ***Different Synthetic Turf 76 GMAX and Bermudagrass 90 GMAX Synthetic Turf vs. KBG ***Different Synthetic Turf 76 GMAX and KBG 57 GMAX 2.25 kg missile 45 cm drop height Clegg versus F355 F355 to Clegg Relationship 2013 F355 after 30 Simulated Traffic Events Clegg Impact Soil Tester after 30 Simulated Events Tennessee Athletic Field Tester (TAFT) Tennessee Athletic Field Tester Athlete weight 35 lbs 330 lbs Running 1 m/s Contact distance 230 mm 4
TAFT TAFT Vertical Force Comparisons Synthetic Turf > Bermudagrass > Kentucky bluegrass TAFT Vertical Force Comparisons 210 lb Athlete Synthetic Turf vs. Bermudagrass ***Different Synthetic Turf 340 lbs. of vertical force and Bermudagrass 324 lbs. of vertical force Rotational Resistance Comparisons Synthetic Turf = Bermudagrass = Kentucky bluegrass Synthetic vs. Kentucky Bluegrass ***Different Synthetic Turf 340 lbs. of vertical force and KBG 302 lbs. of vertical force TAFT Horizontal Comparisons Synthetic Turf > Bermudagrass > Kentucky bluegrass TAFT Horizontal Force Comparisons 210 lb Athlete Synthetic Turf vs. Bermudagrass ***Different Synthetic Turf 254 lbs. of horizontal force and Bermudagrass 234 lbs. horizontal force Synthetic Turf vs. KBG ***Different Synthetic Turf 254 lbs. of horizontal force and KBG 194 lbs. of horizontal force 5
Head Injury Criterion (HIC) When HIC = 1000, 18% of people will suffer traumatic brain injuries When HIC = 250, concussions have occurred in most athletes (Viano, 2005) Playground Head Drop Device Curved projectile mimics head shape Standard - ASTM F1292 ASTM F355E 4.6 kg (10 lbs.) curved missile World Rugby Standard for synthetic turf 1.3 m (51 ) drop height HIC must be less than 1000 2016 HIC for Root Zone & Turf Species Conclusions Determining HIC on Trafficked Bermudagrass Game 0 Game 20 Native ASTM ASTM F1292 Clegg: ~71 avg. F355A: ~119 avg. HIC: ~1,225 avg. (1.3 m) 1.3 m drop on synthetic turf Clegg: ~88 avg. F355A: ~111 avg. HIC: ~370 avg. (1.3 m) Measuring Critical Fall Height to achieve 1,000 HIC USGA Spec: Bermudagrass = 2.5 m ASTM Spec: Bermudagrass = 2.4 m 6
Head Injury Criterium (HIC) changes on bermudagrass w/ soil type and traffic Measuring 2016 HIC for HIC Root for Zone Soil Type & Turf & Turf Species Species Conclusions Game 0 Game 20 Native ASTM ASTM F1292 Determining Critical Fall Height (1,000 HIC) based on Species, Soil Moisture, & Soil Type Athlete to Surface Interactions World Rugby 1.3 m limit Athlete to Surface Interaction Studies Athletic injury mechanisms and risk factors Movement coordination variability Computer simulation of human movement 7
Athlete to Surface Interactions Deceleration and Cutting Movements Outdoor Human Performance Testing Outdoor Human Performance Testing Outdoor Human Performance Testing Soccer ball to Playing Surface Interactions 8
Professional soccer players are emotional All types of surfaces Playing surfaces are crucial for the best play. It s never their fault for a Bad Bounce. (Google 2017) REGULARLY EDUCATE AT UNIVERSITY FIELD DAYS University of Tennessee Research Field Day August 30, 2018 9
John Sorochan, Ph.D. sorochan@utk.edu @Sorochan Adam Thoms, M.S. athoms@utk.edu @UT_CAFS 10