Evidence of the Possibility to Contract the Lower Trapezius, Relaxing

the Upper Trapezius, and Implications on Posture through the Use

of an Innovative Mechanical Device for Physical Training

L. V. Messa

, F. Barberis

, C. Paradiso

, S. Paddeu

, S. Mardessich

, U. Arrigucci

and M. Bonifazi

7,8

Biomedical Engineer, Siena, Italy

Assistant Professor, DICCA, Faculty of Engineering, Genova, Italy

Neurophysiologist MD, Grosseto, Italy

R&D Programs - ESAOTE S.p.A., Genova, Italy

US Product Planning - ESAOTE S.p.A., Genova, Italy

U.O.C. - NINT, AOUS, Siena, Italy

Associate Professor of Physiology, Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy

Technical Coordinator of the Scientific Studies and Research, Centre of the Italian Swimming Federation, Siena, Italy

1 OBJECTIVES

Often, in the execution of movements involving the

shoulder and the back, the predominant activity is

carried out by the Upper Trapezius (UT) muscle, and

in many cases this may be a risk factor for the

integrity of the cervical-dorsal structures. Shoulder

and neck pain could be caused by repeated and

sustained work of posture muscle including Upper

Trapezius (Buckle et al, 2002). Since, from previous

literature, the physical exercises proposed for

making the Lower Trapezius (LT) muscle to train,

make the UT to work more than LT

(Bandy, 2001),

there was the need to create an apparatus that would

involve synergistically the cervical-dorsal muscles,

emphasizing in particular the activity of the LT and

going to relaxing the UT, to reduce consequences of

faulty posture. With the device “Angel’s Wings”,

thanks to a simple distribution of vectors of forces, it

is possible to isolate the LT activity from the UT.

The device “Angel’s Wings”, designed and build by

Eng. Luca Valerio Messa, is patented, and acts

mainly on the axial muscles of the cervical-dorsal

rachis, so it can correct posture of this tract. We used

Surface Electromyography (Richard, 2003),

Echography (Hashimoto, 1999) and Magnetic

Resonance (Dziubai, 2010) to assess the activity

carried out by Trapezius and the resulting benefits in

a group of volunteers. The “Angel’s Wings” is

already used in some physical therapy centres and

gyms, and it is also used by international class

swimmers of the Italian Swimming Federation.

These findings are important because it was believed

that the UT would have to contract higher than the

LT in every physical performance or exercise. Since

the use of this device is simple, the “Angel’s Wings”

appears to be a useful method to reduce the

problems resulting from an excessive activation of

the UT and to improve the postural control.

2 METHODS

The aim of the Angel’s Wings device (Fig.1) is the

distension of the cervical-dorsal spine, with

contemporary rehabilitation of the shoulder joint

position in its natural seat, rather than rotated

forward.

Figure 1: Angel’s Wings; Fig.2: Schematic front view of

the apparatus with the representation of the motory task

respectively to the starting position (2a) and distension

(2b).

The execution of the task is outlined in Figures

2a and 2b: starting from a seated position (2a) each

of the participants were required to extend the arms

(2b), keeping elbows at shoulder height, to lift a

weight through the cables of the equipment. The

weight lifted was in a range between 6 and 8 kg.

Thus, in the dynamic phase, were examined with

sEMG of Trapezius muscle 9 healthy volunteers (6

M, 3 F, 22-64 y) using electromyography Medelec

Sapphyre 1P. Subsequently, 6 healthy volunteers

Messa L., Barberis F., Paradiso C., Paddeu S., Mardessich S., Arrigucci U. and Bonifazi M..

Evidence of the Possibility to Contract the Lower Trapezius, Relaxing the Upper Trapezius, and Implications on Posture through the Use of an Innovative

Mechanical Device for Physical Training.

 2014 SCITEPRESS (Science and Technology Publications, Lda.)

were examined (3 M, 3 F, 29-67 y), with sEMG of

Trapezius muscle by EMG TruTrace. No differences

in the signal of the performance between the two

EMG used have been found. Then, 3 healthy

volunteers (2 M, 29 and 67 y, and 1 F of 39 y) were

examined with ultrasound echography to Trapezius

muscle, during dynamic exercise with Angel's

Wings, by ultrasound MyLab ™ One (ESAOTE,

Genova, Italy). In order to perform the ultrasound

echography, an Angel’s Wings device has been

suitably modified in its structure without altering the

method of use (Fig.3).

Figure 3: Angel’s Wings with modified structure and

unchanged method of use.

Finally, 3 subjects (3 M, 56-67 y), in the group that

participated in the study, were evaluated with MRI

(Avanto 1,5 T; A.G. SIEMENS, Erlangen,

Germany), at the beginning and at the end of a

training period with Angel’s Wings. The Motory

Task was of 2 + 2 minutes of performance duration

with a recovery interval of 2 minutes. The 3 subjects

who underwent MRI, performed the motory task

daily (morning and evening) for 30 days. The

electromyography and the ultrasound echography

scans were performed to determine the activity of

the Trapezius muscle, in the Upper and Lower

portions, during the 4 phases of the Motory Task:

Start position (1), Contraction during lifting (2),

Return phase (3), Final phase of rest (4). The MRI

was performed to highlight the effects induced by

physical exercise performed with Angel’s Wings in

a training period of 30 days.

3 RESULTS

The graph in Figure 4 shows the variation of the

mean of UT activity and of the mean of LT activity,

expressed in mV, during the 4 phases (n=15).

The Table 1

summarizes, in mV, the mean and

the SD of the maximum amplitudes of EMG on UT

and LT, during the 4 phases of the task, and

furthermore shows the relative statistically

differences, for each phases, between the two

portions of the Trapezius muscle, using the “t” Test

and the F Test.

Figure 4: Variation of the mean of UT activity vs

Variation of the mean of LT activity during the 4 phases

(n=15).

Table 1: Mean and SD (n=15) for UT and LT for the 4

phases of the Motory Task and relative “t” Test and F

Test.

A statistically significant difference using both “t”

Test and F Test, in phase 2 (Contraction during

lifting), was found.

Then, the graph in Figure 5 shows, for both

portions, the mean (n=3) of the percentages variation

of the Trapezius muscle section (contraction and

relaxation), monitored by ultrasound echography,

during the muscle workload for each phases of the

Motory Task, considering the phase 1 = 0 for both

UT and LT.

Finally, the Figures 6 to 9 show the MRI results

of one of the 3 subjects (M, 64 y) who were trained

for 30 days with Angel’s Wings. The measurements

to highlight the morphological changes were

performed with the software built into the MR

system (Syngo 8.4 version, A.G. SIEMENS,

Erlangen, Germany).

Figure 5: Mean (n=3) of Percentages variation of the

Trapezius muscle (UT and LT) during the muscle

workload for each phases of the Motory Task, considering

the phase 1 = 0.

Figures 6 (left) and 7 (right): respectively the Pre-training

and the Post-training with Angel’s Wings.

Figures 8 (left) and 9 (right): respectively the Pre-training

and the Post-training with Angel’s Wings.

4 DISCUSSION

Figure 4 shows that, during this type of physical

performance, the activity of the Upper Trapezius is

nearly specular to that of the Lower Trapezius.

The most important phase of the Motory Task

with Angel’s Wings is the phase 2, the Contraction

during lifting. The sEMG results clearly show that

during Phase 2, to a sharp contraction of the Lower

Trapezius corresponds a large relaxation of the

Upper Trapezius. This is important because it allows

us to think about being the first to propose a physical

performance, performed with the proposed

apparatus, that allows contracting significantly the

Lower Trapezius, inducing at the same time a

relaxation of the Upper Trapezius, whereas available

equipment always make to contract the Upper

Trapezius higher than the Lower Trapezius. Figure 5

confirms the sEMG results, especially in the same

phase 2, where at a thickening of the LT section

(contraction) corresponds a thinning of the UT

section (relaxation). Figures 6 to 9 show a

realignment of the cervico-dorsal column, between

the Pre and the Post training, due to a variation of a

few degrees in its curvatures, and clearly show an

improvement in posture because also the gibbus,

caused by a kyphotic posture, appears blunt. This

data is important, considering the fact that the

training period was of 30 days of duration, relatively

short period of time. Moreover, the fact that,

regardless of gender, age, level of training, the

weight was lifted within a range between 6 and 8

kilograms, is indicative that the stimulated muscles

in this performance by the proposed apparatus, have

almost the same degree of training in all persons,

because even the best trained people of the group

could not lift a greater weight in the appointed time.

Today many people, including several categories

of workers, have "postural defects" characterized

mainly by altered distribution of muscle mass (Arts

2010). All of this becomes a tendency to assume a

crouched position forward, characterized by

shoulders moved forward.

This data, although obtained in a limited series,

suggest the use of the proposed equipment to correct

postural defects, as also kyphosis, of the cervico-

dorsal column.

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