Eccentric Exercise Michael A. Shaffer PT, ATC, OCS

 Concentric Exercise  Muscle is loaded as it shortens  i.e. muscle force > load  Eccentric Exercise  Muscle is loaded as it lengthens  i.e. muscle force < load

Eccentric Contractions  “Braking” contractions  Stepping down  Arm deceleration after ball release (pitching)  Control of foot pronation in stance phase  Controlling knee extension during swing phase

Length- Tension Curve

Force- Velocity Curve

DOMS Delayed Onset Muscle Soreness  Micro-tearing of Connective Tissue  i.e. “passive” elements  Inflammatory  ~ 48 hours post  Not ischemia  Immediate  Not lactate  minutes post Desmin Titin

DOMS Treatment

 Protective Effect  Neural  EMG changes  Type I Motor Units  Decreased amplitude, duration  LaStayo et al J Strength Conditioning Res 2008  Mechanical  Intramuscular CT  Cellular  Changes in inflammatory response  McHugh Scand J Med Sci Sports 2003

 30 recreational athletes  15 “failed” traditional management  Awaiting surgery  15 treated with eccentric training  0/15 went on to surgery  All returned to running  6 mos post-op = 3 months Non-op

 Eccentric Training  3 x 15 reps  2 Positions  Passive concentric motion  2x/ daily  Pain OK…..stop if “disabling”  Add weight when pain free or easy

Achilles Tendonitis RCT  Concentric vs. Eccentric Exercise  44 patients  12 week follow up  Outcome measure= satisfaction  18/22 Eccentric  8/22 Concentric  Mafl et al KSSTA 2001

Achilles Tendonitis  Better for midportion vs insertional Achilles tendon  Changed protocol  Insertional tendonopathy  DF only to neutral vs. true DF  4 month F/U  Pain/ Satisfaction Improved  18 Patients Jonsson et al Br J Sports Med 2008

Patellar Tendonitis

 Standard Squat Vs. Decline Squat  17 Patients  Better return to sport  Pain ↓’d with decline  Maintained rest of protocol  Purdam et al Br J Sports Med 2004

Patellar Tendonitis  Decline vs. Step Down  Pain and Outcome score  Essentially Equal  Recommended Decline Young et al Br J Sports Med 2005

Eccentric Exercise- ACL Rehabilitation It’s not just for tendons any more

Safety, Strength Gerber et al JOSPT 2007

1 year F/U Gerber et al PT 2009

The Next Step  Older patients  Slow progression  ↑’d strength w/o inflammation  LaStayo et al J Geriatric Phys Ther 2007   Cardiac patients  ↑’d strength lower oxygen cost  Meyer et al MSSE 2003

Why does it work?  Improved strength  Microstructure of tendon  Collagen deposition  Steroids  Neovascularization  Ohberg & Alfredson KSSTA 2004  Raises the pain threshold Achilles Tendon before and after 12 weeks of eccentric training

Application  3 x 15 Reps  2x/ daily  Passive concentric  12 week program  Mid-portion Achilles  Full DF  Insertional  DF to neutral  Patellar Tendon  Decline Board

Application  LOAD!  Pain 3-7/10  But slowly increase  Concentric first?  Continue activity?  Visnes et al Clin J Sports Med 2005

Everything I ever really needed to know I learned……  From an Icelandic BlogIcelandic Blog

Level 6 Evidence- My take  Alfredson vs. other authors  (4 Systematic Reviews in 2007)  Work through pain (3-7/10)  Outcome Measures  12 week outcomes (i.e. short)  12 weeks of training (i.e. long)  Recreational athletes= best results

My questions  12 weeks duration?  Load need to be painful?  Tendonopathy vs. ACLR  If yes, should we limit activity?  If this makes tendonopathy better, can we be this aggressive with other conditions?