Download Review of “The Biomechanics of Elastic Resistance

Review of “The Biomechanics of Elastic Resistance Training: Implications for Strength
and Conditioning Professionals" by Phil Page [Paper # 018-05-M]
SPECIFIC COMMENTS:
Page, approximate line
1, 5 Most of the research cited is over 5 years old, yet it is referred to throughout the
text as “recent.” The research stands on its own; the purpose of this paper is to describe
research on the biomechanics of elastic resistance.
1, 13 This is not a standard equation found in physics/mechanics texts. Please provide
a reference for it.
1, 16 This is not a standard equation found in physics/mechanics texts. This looks like
the equation for relative strain, not the change in length, in which case the equation in 1,
13 should be for stress, not force. Please correct, or provide a reference for it.
1, 17 This “myth” contradicts the equation on line 1, 13. A band can be approximately
represented as a prism, and a tube can be approximately represented as a rod. The
surface areas (SA in equation 1, 13) for both objects include the length of the object (2 pi
r2 + 2 pi r l and 2hw + 2wl + 2 hl, respectively.) Please resolve.
2, 8
Why is this the most “effective” portion. Is it the most relevant portion?
3, 19 This “myth” statement appears to contradict the statement on line 7 of the same
page. If the strength curve of elastic resistance is not linear and ascending, why should it
be classified as a “unique mode of resistance with linear ascending force properties?”
4, 2 Muscle has a “strength” curve. The curve of the tubing should probably be
named something else, such as resistance curve.
5, 1 A somewhat convincing argument is made that elastic resistance is similar to
isotonic resistance. What are the advantages of using elastic resistance over isotonic
resistance?
5, 3
This whole argument is very confusing to follow. Maximum torque of what?
5, 6
Consider using resistance curve instead of strength curve.
5, 7 Change “distance of the resistance and joint axis” to “distance from the resistance
to the joint axis.” Clarify, the maximum torque of what?
5, 8 Note that your average reader will use the term lever arm to mean the
perpendicular distance from the resistance to the axis of rotation. Therefore, the length of
the lever arm perpendicular to the axis is unclear.
5, 17 This formula is the same as the one you would use with isotonic resistance, not in
contrast to it. The sin(FA) would indicate the angle of the line of gravity with the
segment. Clarify for the reader the difference between lever arms and moment arms, as
you are using them in this context.
6, 1 There is another apparent contradiction. Resolve this comment with 4, 16. The
reader is first given the impression that the change in “force” is so slight that it is the
same as isotonic resistance in the linear region, then is told that the changes in resistance
are offset by the change in FA.
6, 1 You’ve already identified the acronym FA. Either use the acronym or the whole
word, not both.
6, 1 “As the resistance of the band slightly increases, the force angle decreases.” Isn’t
this only true after the arm is elevated above the horizontal? Below the horizontal, it
appears as if both the resistance of the band and the force angle are increasing.
6, 6 The clinical implications is out of place, in between two “myths” with different
subject matter. Consider deleting.
6, 19 Clarify the difference between elastic-based and elastic resistance. Also, this
myth is not discussed in the following paragraph: neither safety nor efficacy is mentioned,
only that cams and pulleys do not have resistance curves that match the strength curves.
7, 3
The research characterized as recent is 5 and 6 years old.
7, 5
The research characterized as recent is 5 years old.
8, 5 The statement “parallel with the targeted muscle fibers” is unclear. Provide
examples.
8,12 It is important if you are going to quantify the resistance that you quantify how
much “slack” to take out of the band.
8, 14 The “myth” is apparently contradicted with the statement in 9, 9 where it is stated
that “using a percentage of RM is not practical when using elastic resistance…”
10, 13 Where there any studies that had unfavorable outcomes?
11, 10 Another apparent contradiction. Resolve this statement with the
recommendations on page 8.
11, 13 What has a lack of inertia? Mass is a measure of inertia, so only massless objects
lack inertia.
11, 20 Resolve the conflict of suggestions that movements should be “slow and
controlled” with the comments in 11, 13 that elastic is ideal for speed and agility training.
12, 9 A majority of the paper is spent trying to note the similarities in torque between
elastic and isotonic resistances. The paper would be greatly strengthened by emphasizing
how it can be used as an adjunct to other strengthening modalities.