In contrast, Ackland (2008) showed that the middle deltoid
displays a peak moment arm length of 12.2 mm at 120 degrees (arms over head), and a minimum moment arm length of zero at 2.5 degrees.
While the anterior deltoid
displays a peak moment arm length greater than the middle deltoid, Keuchle et al (1997) reported that the average moment arm length to be 23.4 mm compared to 16.5 mm, indicating the greater contribution of the middle deltoid moment arm length throughout the full range of motion.
The middle deltoid
displays a peak moment arm length of approximately 25.0 mm at 40 degrees of flexion, while the minimum moment arm length approaches zero at 0 and 120 degrees of adduction (arms to side and across body).
The superior region
displays peak moment arm length with the arms just below horizontal, while the middle and inferior regions display peak moment arm lengths with the arms close to the sides.
The anterior deltoid
displays a peak moment arm (length = 16.8 mm) at zero degrees of horizontal adduction (arms to the side) and its lowest moment arm (length = zero) at 140 degrees of shoulder adduction (arm across body).
The pectoralis major (clavicular head)
displays a peak moment arm (length = +30.2 mm) at 120 degrees (arms over head) and its lowest moment arm length of 2.5 degrees at +3.1 mm (Ackland et al., 2008).
Ackland et al. (2008) showed that the inferior sternocostal head
displays a peak moment arm length at 68 degrees (length = -22.2 mm), and a minimum also at 120 degrees (length = -12.4 mm).
Ettema et al. (1998) found that the short head of the biceps
displays a peak moment arm that ranged between 30.5 to 62.1 mm while the minimum moment arm length was approximately 30.5 to 44.5 mm, based on the maximum and minimum values for 3 cadavers.
The short head of the biceps appears to
display a peak moment arm (length = 9 mm) at zero degrees of supination, while it's lowest moment arm (length = 5.75 mm) is displayed at 60 degrees of supination.
Ackland et al. (2008) showed that the pectoralis major (superior sternocostal head)
displayed a peak moment arm length for shoulder adduction at 41 degrees (length = +32.9 mm) and a minimum at 120 degrees (length = -17.7 mm), while the pectoralis major (inferior sternocostal head) displayed a peak at 64 degrees (length = +33.6 mm) and a minimum also at 120 degrees (length = -16.2.
In support of this, Sugisaki et al. (2010) reported that the triceps
displayed a peak moment arm (length = 23.9 mm) at 30 degrees of elbow flexion and a minimum moment arm (length = 17.4 mm) at 110 degrees of elbow flexion.
Ackland et al. (2008) showed that the pectoralis major (clavicular head)
displayed a peak moment arm length at 120 degrees of shoulder abduction (length = +11.2 mm), and a minimum moment arm length at 2.5 degrees of shoulder abduction (length = -3.0 mm).
Ackland et al. (2008) showed that the pectoralis major (clavicular head)
displayed a peak moment arm length of 30.2 mm at 120 degrees of shoulder flexion (arms above head) and a minimum moment arm length at 2.5 degrees (length = +3.1 mm) of shoulder scapular plane flexion.
In contrast, Ackland et al. (2008) reported the middle deltoid also
displayed a peak moment arm length of only 12.2 mm at 120 degrees of shoulder flexion.
As explained above, the inferior fibers of the latissimus dorsi muscle
display a peak moment arm length of -10.8 mm at 53 degrees of shoulder flexion and a minimum moment arm length of -2.9 mm at 120 degrees.
The inferior fibers
displayed a peak moment arm length of 38.1 mm at a shoulder flexion angle of 71 degrees, while the minimum moment arm length was -3.3 mm at 10 degrees.
The superior fibers of the latissimus dorsi appear to
display a peak moment arm length of -31.5 mm at 71 degrees (arms slightly below horizontal) and a minimum moment arm length of -7.8 mm at 10 degrees (arms close to the sides).
The superior fibers of the latissimus dorsi
displayed a peak moment arm length of 22.1 mm at 45 degrees of shoulder flexion (midway below horizontal) and a minimum moment arm length of -0.1 mm at 120 degrees (arms above the head).
As described above, the inferior fibers of the latissimus dorsi muscle
display a peak moment arm length at 71 degrees of shoulder abduction of -38.1 mm and a minimum moment arm length at 10 degrees of -3.3 mm.
The three regions of the latissimus dorsi appear to function similarly as primary shoulder extensors in the scapular plane (although the superior and inferior fibers seem to have greater peak moment arm lengths than the middle fibers) while
displaying peak moment arm lengths at very different joint angles.
While the posterior deltoid
displayed a peak moment arm length of approximately 30.0 mm at 50 degrees of adduction (arms pointing outwards diagonally), and a minimum moment arm length approaching zero at both full range adduction and abduction.
Not exact matches
Orloff et al. (1997) reported that experienced lifters
displayed lower
peak hip extensor
moments than inexperienced lifters during squats with the same absolute loads.
This was associated with the more acute
peak trunk angles
displayed by the inexperienced lifters, which was taken to imply a greater
moment arm length at the hip joint.
McLaughlin et al. (1978) similarly noted that
peak knee extensor
moments were smaller in individuals who
displayed greater trunk lean and more acute hip angles, which is associated with this type of exercise cue.
Thus it appears that the
peak moment arm length is
displayed between 60 degrees of pronation and a neutral forearm position.
In contrast, Bremer reported that the
peak moment arm length was 60 degrees of pronation, while the minimum
moment arm length was
displayed at 80 degrees of supination.
Murray et al. (1995) found that the
moment arm of the biceps appears to
peak (length = 38 mm) at 90 degrees of elbow flexion, while its minimum (length = 20 mm) is
displayed at 20 degrees of elbow flexion.
The
peak moment arm length appears to
peak during mid-range pronation while its minimum
moment arm length is always
displayed during supination.
At 0 degrees of elbow flexion, with the elbow positioned to 0 degrees of flexion (straight arm) the
peak moment arm is
displayed at approximately 45 degrees of pronation (length = 5 mm), while the minimum
moment arm is
displayed at 60 to 80 degrees of supination (0 mm).
In contrast, the chart shows that the lower sternocostal head of the pectoralis major actually
displays a shoulder extension
peak moment arm of -9.3 mm at 98 degrees (arms just above parallel with the ground).
In contrast, Murray et al. (2002) reported that the
peak moment arm length is
displayed at an angle of 44 degrees (slightly - bent arm).
Nevertheless, both parts of the sternocostal head
display similar
moment arm length to joint range of motion curves that appear as a bell - curve shape that
peaks near the middle of shoulder abduction range of motion.
Keuchle et al. (2000) shows the
peak moment arm length is typically
displayed between 10 degrees of internal rotation (thumb facing up and inward) and 20 degrees of external rotation (thumbs facing up and outward).
As you can see from the chart below, the clavicular head of the pectoralis major
displays the largest shoulder flexion muscle
moment arm out of all parts of the pectoralis major, with a
peak moment arm length of 53.7 mm at 71 degrees of shoulder flexion (arms just below parallel with the ground).
They found that the straight - leg lift
displayed the greatest
peak hip extension
moment (124Nm), followed by the bent - leg lift with the load far from the body (105Nm), and finally the bent - leg lift with the load close to the body (88Nm).
Ackland et al. (2008) reported the anterior and middle deltoid
display similarly large
peak shoulder abduction
moment arm lengths (anterior = 30.2 mm; middle = 29.1 mm), while the posterior deltoid
displayed a
peak shoulder adduction
moment arm length of -15.9 mm.
Between 80 degrees and 40 degrees the
moment arm length linearly increases and reaches a plateau around 30 degrees where its
peak moment arm length is
displayed.
In contrast, Ackland et al. (2008) showed that the posterior deltoid
displayed a
peak shoulder extension
moment arm length of -33.0 mm at 30 degrees of flexion (arm pointing down), indicating that it likely acts as a primary shoulder extensor, second to the teres major while the arm is close to the body.
In the scapular plane,
peak moment arm lengths of the superior, middle and inferior regions are
displayed at 71, 10 and 10 degrees, respectively.
The posterior deltoid
displays a shoulder extension
peak moment arm length at 30 degrees (length = -33.0 mm), while its lowest
moment arm length is
displayed at 120 degrees (length = -16.3 mm).
Peak moment arm lengths are
displayed just below the point where the arms are horizontal in all regions.
The
peak moment arm is
displayed between 0 and 20 degrees of internal rotation (thumb point up and in) measuring 12.0 mm, while its minimum
moment arm is
displayed at -60 degrees of rotation (thumbs up) measuring 7.0 mm (Keuchle et al., 2000).
The the superior and inferior fibers
display the largest
peak moment arm lengths, while the middle fibers
display the smallest.
Ackland et al. (2008) reported that the
peak moment arm length of the latissimus dorsi was
displayed in a wide range between 10 — 71 degrees of shoulder flexion depending on the muscle region measured.
The posterior deltoid
displays a
peak adductor
moment arm length of -15.9 mm at 5 degrees (arms by side), while the lowest
moment arm length was 2.0 mm at 120 degrees (arms above head).
The anterior deltoid
displays a
moment arm length that
peaks at 120 degrees (length = 39.3 mm), while the lowest
moment arm is
displayed at 2.5 degrees (length = 2.1 mm).
Dante's
Peak succeeded in this area because it
displayed patient direction and unsettling silence during its
moments of terror.