Wow, it has been a while since I posted.  After battling what may have been H1N1 for nearly 2 weeks I am back at it.  I just returned from the Sports Physical Therapy Section Meeting in Las Vegas held last weekend.  All the brightest minds in the industry were there covering the latest research with an emphasis on knees and shoulders this year.

I must say I came away most impressed with Dr. Scott Dye.  He is an orthopedic surgeon at the University of San Francisco, CA.  He spoke on several topics but continued to highlight this concept of respecting the “envelope of function” in regard to activity and healing.  It really resonated with me as it sounded a lot like my concept of threshold training.

He believes we have a set envelope of function, if you will, that predetermines how much stress our body will absorb before breaking down.  There is the natural envelope and then an area he termed “supra physiologic load.”  Once we break this barrier of supra physiologic load, then mechanical tissue failure ensues.

He preached using bone scans as a diagnostic tool for measuring whether your body was really at tissue homeostasis as opposed to still being inflamed.  His assertion is that often we push people back to full activity too soon based upon subjective reports of no pain and clinical tests as opposed to measuring the joint itself with a scan to see if it is still reactive.

He raised a few eyebrows when he suggested that he does not let athletes return to play after ACL reconstruction until somewhere near 18 months.  While that may seem crazy, he had some interesting research he has done to show how his post-op patients do not get early arthritis at follow-up as far out as 15 years after surgery. 

In essence, he explained that we as practitioners must progress rehab and training in a very sequential and client specific way based upon this envelope of function theory.  While I am not sure I bought  his rehab time lines lock, stock and barrel, I do believe he is right on track with this envelope of function idea.

I have been saying for years that pain is not a good sign during training or rehab.  My critics have often said you can push through some pain with frozen shoulder, rotator cuff pain and the likes with training in order to move forward.  I have always countered that your body has a threshold to activity.  The only surefire way to progress without re-injury is to adequately gage and understand the threshold level, while adding stress to the system only as able while staying within the threshold.

How do I measure the threshold?  I have included my basic definition below:

With a proper training threshold, the athlete or client learns how to grade and evaluate the stress on his/her body during every practice/training session, while gaining an understanding of the exact threshold itself.  The threshold (activity tolerance level) should increase or progress with subsequent training, and the use of pain or soreness in response ot said stress should be the guiding factor in adding more load or volume.

Key parameters to track include:

  • Pain at rest or before activity
  • Pain during activity
  • Pain after activity
  • Length of time for pain (if present) to resolve or return to baseline

Teaching athletes and clients to track and understand this concept is critical to long term health.  First, you must get them to honestly report their symptoms.  Then, you must earn their trust by reassuring them your goal is to return them to full activity as soon as possible but as safely as possible.  Finally, you must implement the system and relate it to the exercises for them to understand how to measure their body’s response.

As I work with elite level athletes and everyday folks struggling with SLAP tears, rotator cuff impingement and knee arthritis to name a few, I become more convinced that accurately gaging their threshold or envelope of function is the key component when it comes to successful exercise program design and progression.