This was the study to which the blogger was referring (notice the conclusion):
Abstract
American Journal of Veterinary Research
October 2009, Vol. 70, No. 10, Pages 1220-1229
doi: 10.2460/ajvr.70.10.1220
Hoof accelerations and ground reaction forces of Thoroughbred racehorses measured on dirt, synthetic, and turf track surfaces
Jacob J. Setterbo, BS; Tanya C. Garcia, MS; Ian P. Campbell, DVM; Jennifer L. Reese, DVM; Jessica M. Morgan, BS; Sun Y. Kim, DVM; Mont Hubbard, PhD; Susan M. Stover, DVM, PhD
Biomedical Engineering Graduate Group, University of California-Davis, Davis, CA 95616. (Setterbo); J. D. Wheat Veterinary Orthopedic Research Laboratory, Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616. (Garcia, Reese, Morgan, Kim, Stover); Santa Lucia Equine Veterinary Associates, 1924 W Hwy 154, Santa Ynez, CA 93460. (Campbell); Department of Mechanical and Aerospace Engineering, College of Engineering, University of California-Davis, Davis, CA 95616. (Hubbard)
Supported by grants from the Grayson-Jockey Club Research Foundation, the Southern California Equine Foundation, and the Center for Equine Health with funds provided by the State of California pari-mutuel fund and contributions by private donors.
Presented in part at the Veterinary Orthopedic Society Conference, Sun Valley, Idaho, March 2007; the International Conference on Equine Locomotion, Cabourg, France, June 2008; and the Annual Convention of the American Association of Equine Practitioners, San Diego, December 2008.
The authors thank Tara Johnson for racehorse and personnel management, Ellen Jackson for donating racehorses to the study, Dr. Amy Kapatkin for kinematic assistance, and Dr. Neil Willits for statistical consultation.
Address correspondence to Mr. Setterbo (jjsetterbo@ucdavis.edu).
Objective—To compare hoof acceleration and ground reaction force (GRF) data among dirt, synthetic, and turf surfaces in Thoroughbred racehorses.
Animals—3 healthy Thoroughbred racehorses.
Procedures—Forelimb hoof accelerations and GRFs were measured with an accelerometer and a dynamometric horseshoe during trot and canter on dirt, synthetic, and turf track surfaces at a racecourse. Maxima, minima, temporal components, and a measure of vibration were extracted from the data. Acceleration and GRF variables were compared statistically among surfaces.
Results—The synthetic surface often had the lowest peak accelerations, mean vibration, and peak GRFs. Peak acceleration during hoof landing was significantly smaller for the synthetic surface (mean ± SE, 28.5g ± 2.9g) than for the turf surface (42.9g ± 3.8g). Hoof vibrations during hoof landing for the synthetic surface were < 70% of those for the dirt and turf surfaces. Peak GRF for the synthetic surface (11.5 ± 0.4 N/kg) was 83% and 71% of those for the dirt (13.8 ± 0.3 N/kg) and turf surfaces (16.1 ± 0.7 N/kg), respectively.
Conclusions and Clinical Relevance—The relatively low hoof accelerations, vibrations, and peak GRFs associated with the synthetic surface evaluated in the present study indicated that synthetic surfaces have potential for injury reduction in Thoroughbred racehorses. However, because of the unique material properties and different nature of individual dirt, synthetic, and turf racetrack surfaces, extending the results of this study to encompass all track surfaces should be done with caution.
The bold type is mine. That conclusion is not much to be basing mandates on, don\'t you think? You seem to have a much better grasp of the physics that I certainly would. I was basing my point on what I observed only. On dirt the hoof slides and the dirt flies in the opposite direction when it strikes the dirt, on synthetic the hoof sticks right there, I don\'t see how the energy isn\'t sent right back through the hoof into the horse\'s leg in an unnatural or exaggerated way. Also, with the dirt, the horse digs in more and pushes off much better (sliding less) which would seem to indicate (as I have observed) that they would feel more confident on dirt and much less secure on synthetics, often leading to poor performances for horses who don\'t handle the stuff. I know after you run on Hollywood for a few months, the wax wears off and the track gets very slippery on the outside paths. Anyway, the sliding on synthetic seems to be at the push off, the opposite of dirt where the sliding is at impact. In any event, thanks for the physics lesson. I never could get through it in college.
