More Tricks for stretching, part 3

We have been talking about ways to enhance stretching, talking about taking avvantage of reciprocal inhibition (please see part 1 here) and autogenic  (or post isometric) inhibition (please see part 2 here). 

Before we talk about this next one, we need to give you a little background (neurologically speaking). 

Take a look at the picture above and note the posturing of the baby in the 2 positions. These neurological reflexes (or postures) are called symmetrical tonic neck reflexes or responses (STNR’s for short) and were described in animals and men by Magnus and de Kleyn in 1912 (1). This work was later studied and reported by by Arthur Simons in 1916  (2) and later by Francis Walshe in 1923 (3). These were later made popular by Berta and Karl Bobath in the 70’s (who studied Walshes work), whom they are often attributed to (4). 

You next question is “Do these persist into healthy adulthood”? and the answer is a resounding YES (5).

Take a look at the picture above again and note the following: 

• When the neck is flexed, the fore limbs flex (and the muscles facilitating that, bicep, brachialis, anterior deltoid are contracting) and the hind limbs are extending (relatively), with the glutes maximus, quadriceps, foot dorsiflexors contracting.

• Note that when the head is extended, the forelimbs are extended and the hind limbs flexed. Think about the muscles involved. Upper extremity tricep, anconeus, posterior deltoid, lower back extensors, hamstrings and foot plantar flexors facilitated.

The reflex is based on the mechanoreceptors in the neck articulations and muscles and are frequently used by us and many others in the rehabilitation field. Generally speaking, looking up facilitates things which make you extend above T12, and flex below T12. Looking down facilitates flexion above T12 and extension below. 

We would encourage you at this point to “assume” these positions and feel the muscles which are active and at rest.

So, how can we take advantage of these while stretching? 

Think about your head position:

•  If you are standing up and hinging at the hips to stretch your hamstrings (notice we did not say “bent at the waist”; there is a BIG difference in shear forces applied to your lumbar spine) you would probably want your neck bent forward, as this would fire your quads which would in turn ALSO inhibit your hamstrings, in addition to the STNR inhibiting the hamstring. 

• If you were in a hip flexor stretch position, you would want you head up, looking at the ceiling to take advantage of the reflex. 

We are confident you can think of many more applications of this reflex and trust that you will, as it can apply to both upper and lower extremity stretches. Just remember that this reflex is symmetrical and will affect BOTH sides. Of course, there are reflexes that only effect things unilaterally, but that is the subject of another post. 

The Gait Guys. Helping make you better at what you do for yourself and others and assisting you on using the neurology that God gave you. 

1. http://www.worldneurologyonline.com/article/arthur-simons-tonic-neck-reflexes-hemiplegic-persons/#sthash.6QS3Eat3.dpuf 
2. Simons A (1923) Kopfhaltung and Muskeltonus. Ges.Z. Neurol.Psychiatr. 80: 499-549.
3. Walshe FMR (1923) On certain or postural reflexes in hemiplegia, with special reference to the so-called “associated movements.” Brain 46: 1-37. 
4. Janet M. Howle . Symmetrical Tonic Neck Reflex in Neuro-developmental Treatment Approach: Theoretical Foundations and Principles of Clinical Practice.   NeuroDevelopmental Treatment, 2002  p 341 ISBN 0972461507, 9780972461504
5. Bruijn SM¹, Massaad F, Maclellan MJ, Van Gestel L, Ivanenko YP, Duysens J. Are effects of the symmetric and asymmetric tonic neck reflexes still visible in healthy adults?Neurosci Lett. 2013 Nov 27;556:89-92. doi: 10.1016/j.neulet.2013.10.028. Epub 2013 Oct 21.

More effective stretching, Part 2

Last week we looked at one (of many) methods to make stretching more effective, utilizing a neurological reflex called “reciprocal inhibition” If you missed that one, or need a review, click here. 

Another way to get muscles to the end range of motion is to utilize a technique called “post isometric relaxation”. Notice I did not say to lengthen the muscle; to actually add sarcomeres to a muscle you would need to use a different technique. Click here to read that post.

Contracting a muscle before stretching is believed to take advantage of a post isomteric inhibition (sometimes called autogenic inhibition), where the muscle is temporarily inhibited from contracting for a period immediately following a isometric contraction. This has been popularized by the PNF stretching techniques, such as “contract hold” or “contract relax” . EMG studies do  jot seem to support this and actually show muscle activation remains the same (1, 2) or increased after contraction (3-6). Perhaps it is due to an increased stretch tolerance (7,8). 

The technique was 1st described by Mitchell, Morgan and Pruzzo in 1979 (9). These gents felt it was important to utilize a maximal contraction (using 75-100% of contractile force) to get to have the effect. It was later shown by Feland and Marin (10) that a more minimal, submaximal contraction of 20-60% accomplished the same thing.  Lewit felt that a less forceful contraction offers the same results, and combined respiratory assists (inspiration facilitates contraction, expiration facilitates relaxation) with this technique (11). Interestingly, there are bilateral increases in range of motion with this type of stretching, indicating a cross over effect (12). Regardless of the mechanism, the phenomenon happens and we can take advantage of it. 

This is how you do it: 

• Bring the muscle to its end range (maximum length) without stretching, taking up the slack. This should be painless, as this will elicit a different neurological reflex that may actually increase muscle tone. 
• resist with a minimal isometric contraction (20-60%) and hold for 10 seconds.  You can inspire to enhance the effect.
• relax and exhale slowly. It is important to wait and feel the relaxation. Stretch through the entire period of the relaxation. You should feel a lengthening of the  muscle.
• repeat this 3-5 times

This technique can also be used with the force of gravity offering isometric resistance. In a hamstring stretch, you could lean forward while maintaining the lumbar lordosis and allowing the weight of the upper body to provide the stretch. 

Wasn’t that easy? Now you have another tool in your toolbox for yourself or your clients.

The Gait Guys. Giving you useful information and explanations in each and every post.

1. Magnusson SP, Simonsen EB, Aagaard P, Sorensen H, Kjaer M. A mechanism for altered flexibility in human skeletal muscle. J Physiol. Nov 15 1996;497 (Pt 1):291–298
2. Cornelius WL. Stretch evoked EMG activity by isometric coontraction and submaximal concentric contraction. Athletic Training. 1983;18:106–109
3. Condon SM, Hutton RS. Soleus muscle electromyographic activity and ankle dorsiflexion range of motion during four stretching procedures. Phys Ther. Jan 1987;67(1):24–30 
4. Mitchell UH, Myrer JW, Hopkins JT, Hunter I, Feland JB, Hilton SC. Neurophysiological reflex mechanisms’ lack of contribution to the success of PNF stretches. J Sport Rehabil. 2009;18:343–357 
5. Youdas JW, Haeflinger KM, Kreun MK, Holloway AM, Kramer CM, Hollman JH. The efficacy of two modified proprioceptive neuromuscular facilitation stretching techniques in subjects with reduced hamstring muscle length. Physiother Theory Pract. May 2010;26(4):240–250 
6. Osternig LR, Robertson R, Troxel R, Hansen P. Muscle activation during proprioceptive neuromuscular facilitation (PNF) stretching techniques. American journal of physical medicine. Oct 1987;66(5):298–307
7. Mahieu NN, Cools A, De Wilde B, Boon M, Witvrouw E. Effect of proprioceptive neuromuscular facilitation stretching on the plantar flexor muscle-tendon tissue properties. Scandinavian journal of medicine & science in sports. Aug 2009;19(4):553–560 
8. Mitchell UH, Myrer JW, Hopkins JT, Hunter I, Feland JB, Hilton SC. Acute stretch perception alteration contributes to the success of the PNF “contract-relax” stretch. J Sport Rehabil. May 2007;16(2):85–92
9. Mitchell F Jr., Moran PS, Pruzzo NA: An Evaluation of Osteopathic Muscle Energy Procedures. Pruzzo, Valley Park, 1979.  
10. Feland JB, Marin HN. Effect of submaximal contraction intensity in contract-relax proprioceptive neuromuscular facilitation stretching. Br J Sports Med. Aug 2004;38(4):E18.
11. Lewit K: Postisometric relaxation in combination with other methods of muscular facilitation and inhibition. Man Med, 1986, 2:101-104.
12. Markos PD. Ipsilateral and contralateral effects of proprioceptive neuromuscular facilitation techniques on hip motion and electromyographic activity. Phys Ther. Nov 1979;59(11):1366–1373

Making your stretching more effective. 

While I was making linguine and clam sauce for my family, one of my favorite foods that I haven’t had in quite some time( and listening to Dream Theater of course) I was thinking about this post.  Then I remembered about voice recognition on my iMac.  Talk about multitasking!

What do you agree that stretching is good or not, you or your client still may decide to do so possibly because of the “feel good” component. Make sure to see this post here on “feel good”  part from a few weeks ago. 

If you do decide to stretch, make sure you take advantage of you or your clients neurology.  There are many ways to do this. One way we will discuss today is taking advantage of what we call myotatic reflex.

The myotatic reflex is a simple reflex arc. The reflex begins at the receptor in the muscle (blue neuron above) : the muscle spindles (nuclear bag or nuclear chain fibers). This sensory (afferent) information then travels up the peripheral nerve to the dorsal horn of the spinal cord where it enters and synapses in the ventral horn on an alpha motor neuron.  The motor neuron (efferent) leaves the ventral horn and travels back down the peripheral nerve to the contractile portion of the myfibrils (muscle fiber) from which the the sensory (afferent) signal came (red neuron above).  This causes the muscle to contract. Think of a simple reflex when somebody taps a reflex hammer on your tendon. This causes the muscle to contract and your limb moves.

Nuclear bag and nuclear chain fibers detect length or stretch in a the muscle whereas Golgi Tendon organs tension. We have discussed this in other posts here.   With this in mind, slow stretch of a muscle causes it to contract more, through the muscle spindle mechanism.

Another reflex that we should be familiar with is called reciprocal inhibition. It states simply that when one muscle (the agonist) contracts it’s antagonist is inhibited (green neuron above).  You can find more on reciprocal inhibition here.

Take advantage of both of these reflexes?   Try this:

• do a calf stretch like this: put your foot in dorsiflexion, foot resting on the side of the doorframe.
• Keep your leg straight.
• Grab the the door frame with your arms and slowly draw your stomach toward the door frame. 
• Feel the stretch in your calf; this is a slow stretch. Can you feel the increased tension in your calf? You could fatigue this reflex if you stretched long enough. If you did, then the muscle would be difficult to activate. This is one of the reasons stretching seems to inhibit performance. 
• Now for an added stretch, dorsiflex your toes and try to bring your foot upward.  Did you notice how you can get more stretch your calf and increased length? This is reciprocal inhibition at work!

There you have it, one neurological tool of many to give you increased length.The next time you are statically stretching, take  advantage of these reflexes to make it more effective.

 The Gait Guys. Teaching you more  about anatomy, physiology, and neurology with each and every post. 

image from :www.positivehealth.com