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10. BF Transitioning 10/22/15 Transition Carefully !! Transitioning to BF/minimal footwear running Irene S. Davis, PhD, PT, FACSM, FAPTA, FASB Director, Spaulding National Running Center Professor, Physical Medicine and Rehab Harvard Medical School Not weeks, but months! Why Transition?? New Injuries Figure 9 Please identify the site of new injuries since Motivation to Run Barefoot you've started barefoot running: 50 Injury Born to Run 22% More Natural Curiosity Foot Don't Like Shoes Ankle Run Better Knee 13 9% Hip Low Back 64% 3% 3 7 None 5 7 N = 85 1% 1% Altman & Davis, 2012 Dicharry et al, 2014 Rothschild, 2011 Previous Injuries General Transitioning Tips Figure 6 Identify the site of previous injuries that have gone away once you began barefoot running: 50% If you have been a shoe-wearing, heel striker 45% 40% most of your life, it will take patience to switch to 35% barefoot running! 30% 25% 1. Start Slowly – follow transitioning program 20% 15% 2. Pick a smooth paved surface – parks work well 10% 5% 3. Listen to pain!!! 0% 4. DO NOT GO BAREFOOT IF YOU HAVE ANY Foot Ankle Knee Hip Low Back Previously un-injured LOSS OF SENSATION IN YOUR FEET!!!! 509 Barefoot Runners Dicharry et al, 2012 1 10/22/15 Clinical Approach Strengthen lower legs and feet Wean out of orthotics Transition to minimal footwear for walking Running Retraining BF on Treadmill Transition to mild FFS Add minimal footwear at end Warden SJ, Burr DB, Brukner PD: Repetitive stress pathology: bone. In: Magee DJ, Zachazewski JE, Quillen WS (eds.): Pathology and Intervention in Musculoskeletal Rehabilitation. St. Louis, MO: Saunders Elsevier; 2009, pp. 685-705 [ISBN: Why not simply increase cadence? 978-1-4160-0251-2] What is at risk? 1. Foundational Strength Proper FFS gastroc Stretch achilles/ soleus post. tib. Arch/plant. fascia Strengthen Always Do Exercises Barefoot!!! 2. Functional Activities 2. Functional Activities 2 3 1 4 Single Leg Doming and hopping Box Jumps 2 feet, then 1 foot Square Jumps 2 legs then 1 leg 2 10/22/15 3. Retraining Process – Altering Footstrike Timeline for Retraining Requirements 30 single leg heel raises 10 domed hopping 2-4 wks 2-3 wks 2wks** 2wks** 1x/wk 3X/wk 30 Training done BF (to facilitate 25 20 F-up F-up natural FFS pattern) 15 Foundational Retraining* Minutes 10 Strength Metranome/verbal cues as FB 5 Functional 0 Increase cadence by 5-10% 1 2 3 4 5 6 7 8 Activities Session Minimal Treadmill Time Feedback Time footwear Total program (excl f-ups) Shoes added in last session Avg 6 wks, 12 visits * No running outside of retraining ** Increase running 10%/wk Total Clinical Approach Can you see the difference? FFS training Requirements: Realignment training Requirements 30 single leg heel raises 15 aligned single leg squats 10 domed hopping 10 aligned hopping 4 Sessions of BF FFS 8 Sessions of retraining (with FFS) From 10-20 min From 10-30 min Use metranome/verbal Use mirror as FB cues as FB But What about Shoes ? A Little Bit of History Are these minimal shoes a fad ? Jeff Johnson – Nike 1965-1983 50-60’s Ran in thin-soled canvas shoes on hard surfaces Well-trained - Had ‘legs of steel’ – injuries rare! 70’s Running Boom – more inexperienced runners – beginning of cushioned shoes (Cortez) RW published first two running injury surveys 1971 800 runners knee injuries 17.9% 1973 1680 runners knee injuries 22.5% Cavanagh published results of injury study 1979 974 runners knee injuries 30%* *(Taunton 2002 – 2000 runners – knee injuries 42%) 80’s Nike invites Drs. Steve Subotnik, Harry Hlavick, Dennis Vixie - prominent sports DPMs. They encouraged more motion control and cushioning 3 10/22/15 In 4 Short Decades… Recent changes 2005 2009 2010 2014 1972 2012 2013 Are all minimal shoes the same? Do Partial Minimal Shoes Mimic BF? Partial Minimal Shoes 1. Bonacci et al, 2013 Partial minimal shoes more similar to traditional shoes than to BF 2. Willy & Davis, 2013 Partial minimal shoes greater impacts than traditional shoes Have: midsole, heel counter, min heel-toe drop, min arch support Transitional shoes allow for a comfortable heestrike, but offer less damping “I read the book, bought the shoes and now am a FFS!” It is difficult to judge one’s own FS pattern in cushioned shoes Results Goss et al, 2012 “The partial minimalist shoe reported a significantly higher rate of injury incidence throughout the 12-week period” 4 10/22/15 What Constitutes Minimal Footwear? How do true minimal shoes compare to BF? No motion control No cushioning Zero drop No arch support No midsole Minimal shoes similar to BF Shoes of Ron Hill, 1970 Winner of Boston Marathon Squadrone and Gallozzi, 2009 True minimal shoes similar to BF But What Hoka One Shoes ? High Cadence does not always translate into What about increasing cadence? low impacts! Cadence 176, VALR 110 bw/s! Increasing cadence by 7.5% only resulted in an 19% reduction in average and 18% in instantaneous vertical loadrates 5 10/22/15 Why not just FFS in traditional shoes Why not just FFS in Cushioned Shoes? Rates of loading are lowest in all directions in when FFS in min shoes Rice et al, 2015 Increased PF and INV in runner Footwear Matters! with insertional achilles tendinitis Dec. PF and INV What about Highly Cushioned Shoes? Footwear/Footstrike across a marathon Vertical Instantaneous and Average Loadrates Peak Tibial Shock RFS 10-15 gs * ** MFS 8-12 gs <5 gs Novice Hoka Users Novice/Habitual FFS Hoka Users Land Harder on Soft Surfaces Bishop et al, 2006 Ferris et al, 1988, 1999 Eric’s Story May 2007 Underwent bilateral Wick Catheter Very talented 19 yo male runner test for compartment syndrome Recently won a local marathon Top freshman XC runner in the state Elevated Pressures in all 4 Spring track (07) –pain, burning both legs compartments of both legs! Progressed to foot drop during the runs Underwent 8 Fasciotomies! Spent the summer stretching, walking Gradual progression to running 6 10/22/15 Spring 2008 Sought MD advice Fall 2007 Great XC Season PB 16:32 5K No Symptoms All Sx returned Spring Track Fall 2008 Struggled through XC, Trained low intensity, Ran PB of 16:07 Despite 2nd pair of orthotics -legs rock hard and extremely painful after races Spring 2009 Sx intensified - 3rd pr. orthotics – no relief Incr. hip + knee flex to counter the foot drop 2nd in County for the 2 mile Couldn’t manage to alter his footstrike pattern Fall 2009 Recruited for UD XC Running 50 mpw- High intensity Increased to 70 mpw in summer – with Sx Won marathon by 15 min Unable to complete the season Won every race (or PB) he has Dropped off the XC Team run since 4/24/10 Despondent NO SYMPTOMS!! November, 2009 – Vibrams Vibrams allowed more natural FS Nothing to lose Addressed the underlying mechanics Progressively increased running We need to get off of our heels! 7 10/22/15 Nothing in Biology Makes Sense Except in the Light of Evolution Thank You You can not out-engineer Nature Spaulding Naonal Running Center www.runsnrc.org 8 .
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