Exercise Principles: How
much, how often, how
intense?
Principles of Exercise Physiology
& Strength Training
Lori Burkhead Morgan, PhD, CCC-SLP
Purpose of this talk

Muscle structure & function

Response to deconditioning & conditioning

Activity vs. exercise

Application of exercise principles in dysphagia
rehabilitation
2
Wisdom from a Snapple cap

“Relative to size, the tongue is the strongest
muscle in the human body”

Snapple “Real Fact” #810
Neuromuscular Development
4
How muscles work
5
Skeletal Muscle Composition


Type I
Type II
IIa
 IIb


Slow-twitch, fatigue resistant
Fast-twitch, fatigable
Adaptable, more efficient Type II fiber
Best force generation, but inefficient
Whole muscle contains blend with a
predominance of one type
6
Oropharyngeal Muscle Composition

Type II is predominant

Type I, IIa, IIb and hybrid fibers

Unique architecture
Regional differences in proportion & diameter of
fiber types
 Complex arrangement

Kent, 2004.
7
Oropharyngeal Muscle
Composition

Muscular hydrostat
Tongue
 Pharynx?

Kairaitis, 2010.
8
Muscular Hydrostat




Composed entirely of muscle with complex, 3dimentional fiber arrangement.
Maintains constant volume, as a fluid-based muscle
structure.
Shape alteration is dependent on redistribution of
hydrostatic tissue pressure.
Mechanical effect depends upon integrated activity of
other muscles within the organ.
Kairaitis, 2010.
9
Why do we care?


Do contemporary exercise principles apply to
these unique structures?
In what ways can we maximize function of these
muscles?
10
Muscle response to deconditioning &
conditioning
Conditioned:
John Burkhead – World record bench
press, 515 lbs.
Deconditioned:
Muscle-wasting, cachexia
11
Deconditioning
PERIPHERAL
 Atrophy

Loss in cross sectional area



Decreased size
Force-generating capacity
(“strength”)

Fiber-type shift


CENTRAL
 Decreased neural activation
(“drive”)
More easily fatigued

Sarcopenia


Age-related reduction in muscle
fibers
Preferentially affects Type II
12
Decrease in number of
motor units
Remodeling of motor units
Deconditioning

Muscle atrophy & deconditioning
4-6 wks bed rest (young, healthy) = ~40% decrease
in strength*
 Ill & elderly even more susceptible**

*Bloomfield, 1997.
**Urso et al, 2006.
13
“Vicious Loops” in Dysphagia?
Dysphagia - NPO
Decreased swallow frequency

Murray et al, 1996

Swallow frequency/min:


Deconditioning

Exacerbation of
dysfunction
14
Normals = 3
Dysphagia, - asp = 1.16
Dysphagia, + asp = .71
Conditioning
PERIPHERAL

Hypertrophy



CENTRAL

Increased cross sectional area
Increased force-generating
capacity

Fiber type shift

Increased endurance
Increased neural activation
(“drive”)
Increased number of motor
units
4-8 wks.
6-12wks.
15
***Plasticity***



Cortical reorganization
Blood flow changes
Peripheral muscle changes
Barbay et al, 2006; Gobbo & O’Mara, 2005; Kleim et al, 2003; Nudo, 2003,
2005, 2007; Nudo & Friel, 1999
16
Therapeutic Exercise:
Exercise vs. Activity
Exercise: What is it?

Strength, Timing, Coordination, ROM*
Specificity
 Intensity

Overload principle (> 60% MVC)
 Progressive resistance
 Volume & frequency of exercise

*Burkhead LM, Sapienza CM, Rosenbek JC (2007)
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What qualifies as EXERCISE ?
Exercise is activity that challenges the body beyond
it’s typical level of activity


Exercise that does not force the neuromuscular system beyond
usual activity will not elicit an adaptation
Resistance training recruiting 60-75% effort is required to
achieve the greatest improvement
19
As your muscles get stronger, the
challenge must also increase to elicit
continued improvement!
20
Exercise: When?

The sooner the better



“Use it or lose it” principle*
Early intervention can improve diet tolerance, airway
protection & overall nutrition**
Pre-Treatment exercise beneficial in H&N Ca***
*Kleim & Jones, 2008.
** Emstahl et al, 1999; Carnaby et al, 2006.
***Kulbersh et al, 2006; Carroll et al, 2008.
21
“Our patients are too sick ”



If you do nothing you will improve nothing.
Function may only get worse as you “wait” for the
patient to “get better.”
Remember the concept of “vicious loops.”
22
Regardless of the tool used…
23
…be mindful of exercise
principles, the patient’s specific
target areas, and the patient’s
disease process.
24
Case examples

Note the following:
Prior therapy had plateaued
 Intensity and use of tools for progressively
increasing resistance/challenge were key in progress
 Progress was dramatic in a relatively short period of
time

25
Case Report #1
•60
y.o. man
•Hx/o
right CVA
•Severe
dysfunction,
silent aspiration
•Pt
carried “spit cup”
•PEG
•1
dependent
yr. of IP & OP Tx
•Referred
for Myotomy
26
Case Report #1
•8
weeks of therapy:
BOT and pharyngeal
strengthening & laryngeal
closure
•Used
•Pt
sEMG & NMES
resumed unrestricted
oral diet
•PEG
removed
27
•Hx/o
2 left CVA’s, DM,
Case Report #2
renal failure w/ transplant,
heart disease
•4
months Severe dysphagia
following C-spine surgery
•PEG
dependent, frank
aspiration w/ ice chips
•In
dysphagia tx 3x/wk at
local rehab
•Had
~ 1 yr Tx, prior
28
•16
weeks of therapy: oral
& pharyngeal strength,
Case Report #2
airway protection, timing
•Used
EMST, isometric
tongue strengthening,
sEMG
•Unrestricted
oral diet;
chin tuck with liquids
•PEG
removed
29
Thank you for your attention.
[email protected]