Plan on Changing Your Footstrike? Not So Fast MAJ Bradley J. Warr, Ph.D., PA-C Chief, Military Performance Branch bradley.j.warr.mil@mail.mil Joseph Seay, Ph.D. Rebecca Fellin, Ph.D. US Army Research Institute of Environmental Medicine Natick, MA 01760 5007
Acknowledgments Rebecca E Fellin, PhD Shane G Sauer, MS LTC Donald L Goss, PhD, DPT Peter Frykman, MS Joseph F Seay, PhD SSG Carl Larcom Participating Units and CDRs Many others
Disclaimers The opinions or assertions contained herein are the private views of the author(s) and are not to be construed as official or reflecting the views of the Army or the Department of Defense. Human subjects participated in these studies after giving their free and informed voluntary consent. Investigators adhered to the DoD Instruction 3216.02 and 32 CFR 219 on the use of volunteers in research. Any citations of commercial organizations and trade names in this report do not constitute an official Department of the Army endorsement of approval of the products or services of these organizations.
Overview While there may be therapeutic indications for footstrike pattern alterations, changing a footstrike pattern may not be the answer in the absence of a problem. If one is attempting to change their footstrike pattern in an effort to prevent injury or improve performance, they may want to consider the preliminary findings of a large United States Army study that does not show a significant difference between footstrike patterns in terms of reported performance or running related injuries.
Outline Background Relevant Research USARIEM s Findings
USARIEM US Army Research Institute of Environmental Medicine Natick, MA COL Thomas Eccles III, Commander MISSION: conduct biomedical research to improve and sustain Warfighter health and performance under all conditions.
Military Performance Branch Main objectives: Improve Soldier Physical and Cognitive Performance Injury Prevention/Mitigation Bone health DEXA High resolution pqct Stress fracture Biomechanics Motion capture system Force sensing treadmill Load carriage Physical Performance Physical activity levels Optimization/prediction of performance TRADOC Physical Demands Injury Epidemiology -TAIHOD (Total Army Injury and Health Outcomes Database) Cognitive TBI assessment tools & validation Occupational exposure Molecular & Genetic Animal and cell based models Muscle repair and regeneration Biomarkers for skeletal muscle injury
Why is the Army interested in running? It has been theorized that individual running styles may influence injury patterns, yet there is very little research that supports or refutes this Why a resurgence in running research?
2009 - Popularized the idea of barefoot running Published 2009
2010
Warr, B.J., Fellin, R.E, and Seay, J.F. Clinical Advisor, 2014 (data courtesy of Altman and Davis)
2011
2012
2012-10 patients with CECS determined by intracompartmental pressures (ICP) - Trained to run without the heel-strike over a 6 week period by clinicians - At 6 weeks and 1 year post intervention, ICP and pain decreased while performance improved
2013-93% of runners heel-strike -More elite performers are less likely to heel-strike
Relevance to US Army If some of these discussed theories and findings regarding footstrike, injury, and performance can be applied to Soldiers, then maybe there is value in large scale re-training interventions.
Purposes of Study 1. Characterize the running styles of Army Soldiers 2.To determine if there is a difference in injury patterns amongst different styles of running VS
Participants 1000+ Soldiers Who? Men and Women Multiple career fields represented Multiple locations Ft Carson Ft Lee Ft Story Ft Eustis Ft Sam Houston
What? Video recording of runner s lower body Reviewed to determine foot strike pattern Picture of shoes Completed survey Medical records review for 1 yr (ongoing)
How? Day of data collection Unit reported for testing following a warm-up Soldiers briefed/consented Soldier ran for data collection Soldier completed survey Time Commitment/Soldier: 1 x 1-hr session Conducted during PT time
Mileage Combined Arms Battalion Combined Arms Battalion (n=341) 80% of Soldiers reportedly ran 15 miles/week 54% ran 6-10 miles/week
Characterization Combined Arms Battalion Combined Arms Battalion Only (all male=341) Heelstrike 87% Non-heel Strike 13% Midfoot 9% Forefoot 4% Soldiers are not another species Reviewer, Military Medicine
Characterization All Installations Entire Cohort (n=1027; M=795, F=232) Warr et al, ACSM 2014
Injury Combined Arms Battalion Self-report via survey Warr et al, Military Medicine, Accepted 2015
Injury All Installations Warr et al, ACSM 2014
Injury All Installations Sex Differences (not necessarily related to FS) Overuse Injury v Sex Females approximately 2 times more likely to report overuse injury, consistent with previous reports. Warr et al, ACSM 2014
Performance Combined Arms Battalion Combined Arms Battalion (n=341) 2 mile run times HS = 14:48 NHS = 14:48 Warr et al, Military Medicine, Accepted 2015
Performance All Installations Seay et al, ACSM 2014
Minimalist Shoes Barefoot or minimalist shoes encourage forefoot strike pattern (?)
Minimalist Shoes All Installations In Soldiers running 5 miles/week (n=851), their self-perception of FSP was not reliable (~50% accuracy) Fellin et al, ACSM 2014
Continuing Work Medical Records Inventory Additional Analysis Factors relating to injury
Summary Approximately the same distribution of NHS:HS in Soldiers as previous reports No difference amongst Soldiers in injury profile by FSP No difference amongst Soldiers in performance by FSP Soldiers about 50% accurate in knowing FSP, regardless of shoe type
If You Still Want To Try
Thank You MAJ Bradley J. Warr, Ph.D., PA-C Chief, Military Performance Branch bradley.j.warr.mil@mail.mil US Army Research Institute of Environmental Medicine Natick, MA 01760 5007