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Introduction

The use of weights for muscle recovery and devel-opment today is a consolidated reality in Physio-therapy and Physical Education. The double pulleyis useful for the control of movement reaction22 andit is reliable to rehabilitation.6

Using electromyography, many investigators havefocused their research on the evaluation of musclecontraction during movements performed on equip-ment for muscle training and development. Gas-trocnemius and gluteus maximus are essential groupsof muscle related to gait, posture and great part of

human movements.5,20 Gardner et al.,3 reported that

gastrocnemius does not flex the knee if the foot is incomplete plantar flexion. Conversely, when the kneeis completely extended, the extended gastrocnemiustends to push the foot for plantar flexion due to lig-ament action. If the foot is in complete dorsal flex-ion, the extended gastrocnemius tends to push kneefor flexion. Williams et al.,24 stated that, in additionto contributing to knee flexion, gastrocnemius actsas a primary motor of plantar flexion. Gluteus max-imus participates in powerful movements such asstanding up and during jumping. Studies related togluteus maximus suggest that it is the main extensor

of the hip and its weakness is compensated by thepotential of the hamstrings. Besides, gluteus max-imus acts in powerful movements such as standingup and during jumping.9 Therefore, the knowledgeof their kinesiologic and biomechanic role is veryimportant to understand the human movement

Electromyogr. clin. Neurophysiol., 2004, 44, 000-000. 1

1 Ph.D. Speech Pathology and Audiology Department, Faculty of Philos-ophy and Sciences, Paulista State University (UNESP), Marlia, SP,Brazil

2 Physical Therapist. Special Education Department, Faculty of Philos-ophy and Sciences, Paulista State University (UNESP), Marlia, SP,Brazil

Electromyographyc evaluation of movements of lower limb indouble pulley system equipment: comparison betweengastrocnemius (caput laterale) and gluteus maximus

N. Tassi1 and V. Engrcia Valenti2

Abstract

It was evaluated movements of lower limb in the double pulley system equipment on ten male volunteers dur-

ing contraction of gastrocnemius (caput laterale) and gluteus maximus muscles in the following movements: 1)

hip extension with extended knee and erect trunk, 2) hip extension with flexed knee and erect trunk, 3) hip

extension with flexed knee and erect trunk, 3) hip extension with extended knee and inclined trunk, 5) hip abduc-

tion along the midline, 7) hip abduction with extension beyond the midline, 8) adduction with hip flexion beyond

the midline, 8) adduction with hip flexion beyond the midline, and 9) adduction with hip extension beyond themidline. Myoelectric signals were taken up by Lec Tec surface electrodes connected to a 6-channel Lynx elec-

tromyographic signal amplifier coupled with a computer equipped with a model CAD 10/26 analogue digital con-

version board and with a specific software for signal recording and analysis. We observed weak gastrocnemius mus-

cle activity for all movements studied. In the case of gluteus maximus, the most important potentials were observed

for movement 2, while for the remaining movements the actions were of reasonable intensity. Compared to glu-

teus, gastrocnemius was less required for all movements.

Key-words: Double pulley Electromyography Gastrocnemius Gluteus Maximus.


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science. However, it was not found any study relatedto evaluation of movements of gastrocnemius andgluteus maximus in the double pulley equipment.

In view of the above considerations, the objec-tive of the present study was to compare movementsof lower limb between gastrocnemius (caput laterale)and gluteus maximus during hip extension, hip

abduction and hip adduction with trunk and knee indifferent positions.

Material and methods

Study population

The study was conducted on 10 right-handedmale volunteers aged 18 to 25years old who prac-ticed muscle building, with similar anthropometriccharacteristics. The study was approved by the

Ethics Committee of Paulita State University Marlia, SP, Brazil, and was fully explained beforewritten informed consent was obtained from allparticipants.

Electromyographyc mensuration

The muscle potentials were recorded using LecTec surface electrodes connected to a 6-channel Lynxelectromyographic signal amplifier, calibrated at500 v, coupled to a computer equipped with an

analogue digital converter, A/D (CAD 10/26) andwith specific software for the recording and analy-sis of electromyographic signals. The electrodes werepositioned as indicated by Delagi et al.:2

- Gastrocnemius (caput laterale): 8cm below thefacies poplitea femoris;

- Gluteus maximus: at the middle point betweenthe linea glutea posterior os ilium and the tubero-sitas glutea.We evaluated movements of gastrocnemius and

gluteus maximus in the Double Pulley system equip-ment with trunk and hip in different positions:

1: hip extension with extended knee and erect trunk;2: hip extension with flexed knee and erect trunk;3: hip extension with extended knee and inclined

trunk;4: hip extension with flexed knee and inclined trunk;5: hip abduction along the midline;

6: hip abduction with hip flexion beyond the mid-line;

7: hip abduction with hip extension beyond the mid-line;

8: hip adduction with hip flexion beyond the mid-line, and

9: hip adduction with hip extension beyond the mid-

line.Numerical analysis was performed by signal inte-gration (amplitude and frequency, at beginning andend of data collection) and the effective value () wasobtained, which permitted graphic and statisticalanalysis of the results. To synchronize the acquisitionof the electromyographic data and the correspondingposture during the movement, a photoelectronic sys-tem was used to activate an incandescent bulb, whichemitted a common signal to the EMG apparatus(Lynx - Tecnologia Eletrnica Ltda.).

Statistical analysis

We used double factor ANOVA without replica-tion, available in Microsoft Excel (version/1997). Wefirst identified the occurrence of significant differ-ences in muscle actions among the nine movements.To identify the site where these differences occurred,we paired the movements for analysis in the follow-ing order:- movements: 1 vs. 2; 1 vs. 3; 1 vs. 4; 1 vs. 5; 1 vs.

6; 1 vs. 7; 1 vs. 8; 1 vs. 9;

- movements: 2 vs. 3; 2 vs. 4; 2 vs. 5; 2 vs. 6; 2 vs.7; 2 vs. 8; 2 vs. 9;- movements: 3 vs. 4; 3 vs. 5; 3 vs. 6; 3 vs. 7; 3 vs.

8; 3 vs. 9;- movements: 4 vs. 5; 4 vs. 6; 4 vs. 7; 4 vs. 8; 4 vs. 9;- movements: 5 vs. 6; 5 vs. 7; 5 vs. 8; 5 vs. 9;- movements: 6 vs. 7; 6 vs. 8; 6 vs. 9;- movements: 7 vs. 8; 7 vs. 9;- movements: 8 vs. 9.

Significant differences in potentials were observedbetween gastrocnemius (caput laterale) and gluteusmaximus muscles during nine movements. The mus-

cles were again analyzed separately for each move-ment to identify the occurrence of the significantdifferences, as follows:- movement 1; - gastrocnemiusgluteus maximus;- movement 2: - gastrocnemiusgluteus maximus;

and so on until movement 9.

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Results

Considering the results of ANOVA, the weakactivity pattern of the gastrocnemius was similar forall movements (Figure 1). Statistically significant dif-ferences were detected (Table1), specially, betweenmovements 2x3, 2x6, and 4x6 (Table2).

The most important activity of the gluteus max-imus was observed for movement 2, although activ-ity levels of reasonable intensity were also recordedfor the other movements (Figure 2).

Statistical analysis of the effective values revealedsignificant differences in the muscle potentials of thegluteus maximus during the nine movements, asshown in Table3.

Pairwise comparison of the movements showedsignificant differences in the gluteus maximus poten-

tials for the following movements: 1x4, 1x6, 1x7, 2x3,2x4, 2x6, 3x4, 3x5, 3x6, 3x8, 3x9, 4x5, 4x8, 4x9, 5x6,5x7, 6x8, 6x9, 7x8, and 7x9 (Table4).

The gastrocnemius muscle (caput laterale) showed

weaker potentials than the gluteus maximus for all

movements studied (Figure 3), with the differences being

significant for movements 1, 2, 3, 5, and 8 (Table4).

Discussion

Based on the results of the present study, gas-trocnemius was less required than gluteus maximusduring all movements in the double pulley. Webelieve that the potentials values shown by gluteusmaximus during all movements are due to its actionon the hip, thigh and trunk.

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Table 1. Statistical analysis of the mean effective values of the gastrocnemius (caput laterale) muscle,obtained during the movements performed

ANOVA

Source of variation SS Df MS F P Value Critical F

Volunteers 9384,554 9 1042,728 37,84423 7,86E-24 2,012705Movements 571,2989 8 71,41237 2,591803* 0,015096 2,069832Error 1983,828 72 27,55317

Total 11939,68 89

Table 2. Statistical analysis of the mean effective values of the gluteus maximus muscle, obtained during the movements performed

ANOVA


Volunteers 23202,14 9 2578,016 11,18313 1,02E-10 2,012705Movements 18581,82 8 2322,728 10,07572 2,61E-09 2,069832Error 16597,96 72 230,5272Total 58381,92 89


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There are studies that support our data, whichsuggested the weak activity of gastrocnemius dur-ing movements of hip extension in different pos-tures10,14 and studies of Houck,8 Hollinshead,7 andJonkers et al.,9 which reported that gluteus maximus

exerts powerful actions in these regions, especiallyduring hip extension with flexed knee and erecttrunk and that its weakness is compensated by thepotential of the hamstrings.

During movement 1gluteus maximus presentedgreater mean values than gastrocnemius. Recent

studies11,13 support our data, it was concluded thatmuscle position relative to surrounding tissues andmuscle length co-determines muscle force, but it wasnot possible to determine whether this also occurs intriceps surae.

We believe that during hip extension with flexedknee and erect trunk (movement 2), gastrocemius

showed expressive values because knee was flexed.According to Tassi et al.21 gastrocnemius presentsits greatest action potential at the beginning of kneeflexion with the feet in plantar flexion in the LegPress. The strong potentials observed in gluteus max-imus for movement 2 differed from the muscle actionobtained for exercises 1, 3, 4, 5, 6, 7, 8 and 9 (mod-erate potentials), since they were related to simulta-neous extension movements of the trunk, hip andflexed knee, in contrast to the low intensity poten-tials.

Gastrocnemius showed its greatest value during

hip extension with extended knee and inclined trunk(movement 3), whereas this movement was one ofthe weakest performance for gluteus maximus.Recent studies suggest that lateral and medial gas-trocnemius play an important role in transverse andfrontal plane movements during cut tasks.8 Gluteus

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Table 3. Statistical analysis of the mean effective values of the gluteus maximus muscle,obtained during the movements in which were detected significant differences.

ANOVA


Movement 14 1782,65 1 1782,65 18,90859 0,001855 5,117357Movement 16 1528,976 1 1528,976 14,89458 0,003851 5,117357Movement 17 1020,02 1 1020,02 19,09542 0,001798 5,117357Movement 23 5306,63 1 5306,63 9,2942 0,013823 5,117357Movement 26 7859,027 1 7859,027 15,69045 0,003299 5,117357Movement 34 249,7831 1 249,7831 8,395533 0,017667 5,117357Movement 35 1074,431 1 1074,431 10,90001 0,009208 5,117357Movement 36 160,9146 1 160,9146 12,7823 0,005975 5,117357Movement 38 2966,804 1 2966,804 14,87129 0,003869 5,117357Movement 39 3960,987 1 3960,987 12,70442 0,006078 5,117357Movement 45 2360,313 1 2360,313 29,28892 0,000426 5,117357Movement 48 4938,282 1 4938,282 28,98679 0,000442 5,117357

Movement 4

9 6200,129 1 6200,129 23,44034 0,000919 5,117357Movement 56 2066,951 1 2066,951 25,39755 0,0007 5,117357Movement 57 1466,842 1 1466,842 13,4256 0,005202 5,117357Movement 68 4509,605 1 4509,605 29,87722 0,000397 5,117357Movement 69 5718,624 1 5718,624 21,74533 0,00118 5,117357Movement 78 3598,708 1 3598,708 19,07007 0,001805 5,117357Movement 79 4686,391 1 4686,391 14,69788 0,004004 5,117357


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maximus is evidenced as a synergist muscle duringmovements of hip extension in orthostatic position,it is not the main muscle during this movement.24

Its superior fibers are involved in powerful abduc-tion, it induces tension of the fasciae latae and itstabilizes the femur above the tibia when the femoralextensors are relaxed.24

With respect to movements 2 and 4, hip extensionwith the knee flexed and an erect and inclined trunk,respectively, we believe that the potential actionsrecorded for gastrocnemius were only due to theaction of this muscle on knee flexion. This assump-tion is supported by studies of Laplaud et al.10 andTscharner et al.23 Furthermore, the weak activity ofthis muscle during movements 2 and 4 may beexplained by the fact that gastrocnemius is unable toexert maximum potential on ankle and knee at thesame time during movement in the Leg Press21 andthat it was noted that gastrocnemius fibers are very

short during knee flexion, which impairs the simul-taneous execution of these actions.10,19

We believe that our results related to gluteus max-imus at the movement 4may be explained by stud-ies of Neptune et al.16 They suggested that the con-centric contraction of gluteus maximus is expectedto control hip flexion or stabilize pelvis and preventstance leg collapse by acting to extend the hip. Onthe other hand, no important participation of gas-trocnemius muscle was observed during movements5, 6, 7, 8 and 9 whether compared to gluteus max-imus, we suggest that this fact could be explained by

its insertion. Our data coincide with studies ofGoodwin,4 which concluded that gastrocnemius wasunreliable while vastus medialis was reliable in ortho-static position.

We evidenced greater potential of gluteus max-imus than gastrocnemius (caput laterale) contrac-

tion during hip abduction with hip extended. It maybe suggested that the rigid supporting system of thepelvic deltoid help gluteus maximus to effectuate itsgreater potential at those movements. Our resultsare supported by data of Nyland et al.,17 which indi-cated that the pelvic deltoid attaches indirectly tofemur through the intermuscle thigh septa, the ili-otibial tract and the tendinous insertion of the cau-dal gluteus maximus to the gluteal tuberosity.

At movement 6 and 7 it was not seen an impor-tant participation of gluteus maximus. It is sup-ported by studies of Sadegui et al.,18 which indicatedthat gluteus maximus is not important during hipextension and hip flexion with hip abduction. Dur-ing hip adduction with hip flexion beyond the mid-line (movements 8) gluteus maximus exhibitedimportant values. Furthermore, gluteus maximuspresented greater potential values during hip adduc-tion with hip extension beyond the midline (move-

ments 9). It supports studies of Birnbaum et al.,1

which evidenced that gluteus maximus is importantto hold femoral head in orthostatic position.

Concluding remarks

In conclusion, it was observed weak but homo-geneous gastrocnemius muscle activity during allmovements in this study and mean values related togluteus maximus demonstrated that it was requiredduring all movements. The new findings of the cur-

rent study suggest that gastrocnemius is less requiredthan gluteus maximus for all movements evaluatedin the double pulley. Future studies may also con-sider the effect of gender and age and influence ofother muscles that act in those movements in dou-ble pulley.

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Table 4. Statistical analysis of the mean effective values of gastrocnemius andgluteus maximus muscles during movements 1; 2; 3; 5; 8 e 9

ANOVA

Source of variation SS Df MS F P Value Critical

Movement 1 3575,673 1 3575,673 9,35047 0,013619 5,117357Movement 2 10734,2 1 10734,2 10,56093 0,010001 5,117357Movement 3 1370,506 1 1370,506 10,62439 0,009846 5,117357

Movement 5 4391,462 1 4391,462 22,92739 0,00099 5,117357Movement 8 7154,788 1 7154,788 24,60354 0,00078 5,117357


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References

1. HOLLINSHEAD, W. H. and ROSSE,C. :ANATOMIA. 4ed. Rio deJaneiro. Intelivros. 1991.

2. HOUCK, J.: Muscle activation patterns of selected lowerextremity muscles during stepping and cutting tasks. J Elec-tromyogr Kinesiol. 2003;13(6):545-54.

3. JONKERS, I., STEWART, C. and SPAEPEN, A.: The comple-mentary role of the plantarflexors, hamstrings and gluteus

maximus in the control of stance limb stability during gait.Gait and Posture, 2003; 17: 264- 272.

4. LAPLAUD, D., HUG, F. and GRLOT, L.: Reproducibility ofeight lower limb muscles activity level in the course of anincremental pedaling exercise. Journal of Electromyographyand Kinesiology, 2006; 16: 158166.

5. LARSSON, B., KADI, F., LINDVALL, B. and GERDLE, B.: Sur-face electromyography and peak torque of repetitive maxi-mum isokinetic plantar flexions in relation to aspects of mus-cle morphology. Jour Elect Kines, 2006; 16: 281290.

6. LI, L., Landin, D., GRODESKY, J. and MYERS, J.: The func-tion of gastrocnemius as a knee flexor at selected knee andankle angles. J Electromyogr Kinesiol. 2002; 12:38590.

7. MAAS, H., BAAN, G.C. and HUIJING, P.A.: Muscle force is

determined also by muscle relative position: isolated effects.J Biomech. 2004; 1:99110.8. MOHR, K. J. et al.: Electromyographic of stretching: the effect

of warm-up. Clin J Sport Med, 1998; 8, 215 220.9. MONTE, G.D., ARAMPATZIS, A . , STOGIANNARI, C. and KARA-

MANIDIS, K.: In vivo motion transmission in the inactive gas-trocnemius medialis muscletendon unit during ankle and knee

joint rotation. J Electromyogr Kinesiol, 2005; xxx: xxxxxx.10. NEPTUNE, R.R.,ZAJAC, F.E., and KAUTZ, S.A.: Muscle force

redistributes segmental power for body progression duringwalking. Gait and Posture, 2004; 19: 194205.

11. NYLAND, J., KUZEMCHEK,S . ,PARKS, M. , CABORN, D.N.M.:Femoral anteversion influences vastus medialis and gluteusmedius EMG amplitude: composite hip abductor EMGamplitude ratios during isometric combined hip abduction-external rotation. J Electromyogr Kinesiol2004; 14: 255261.

12. SADEGHI, H., SADEGHI, S., PRINCE, ALLARD, P., LABELLE,H. and VAUGHAN, C.L.: Functional roles of ankle and hipsagittal muscle moments in able-bodied gait. Clin Biomech,2001; 16:68895.

13. SANDERSON,D.,MARTIN, P.E., HONEYMAN, G. and KEEFER,J.: Gastrocnemius and soleus muscle length, velocity, andEMG responses to changes in pedalling cadence. Journal ofElectromyography and Kinesiology, 2006 (in preparation).

14. STEWART, C., POSTANS, N., SCHWARTZ, MH., ROZUMALSKI,A. and ROBERTS, A.: An exploration of the function of thetriceps surae during normal gait using functional electricalstimulation. Gait Posture. 2007 Jan 12; [Epub ahead of print]

15. Tassi N et al. Electromyographic behaviour of the gastroc-

nemius muscle during knee extension and flexion performedon the Leg press. Electromyography and Clinical Neurophisi-ology, 1999; 39: 367377.

16. TASSI, N. and GONCALVES, M.: Electromyographic valida-tion of the double pulley equipment during movements ofthe lower limbs. Electromyogr Clin Neurophysiol, 2002;42(8):473-80.

17. TSCHARNER, V.V. and GOEPFERT, B.: Estimation of the inter-play between groups of fast and slow muscle fibers of the tib-ialis anterior and gastrocnemius muscle while running. Jour-nal of Electromyography and Kinesiology, 2006; 16: 188197.

18. WILLIAMS, P. L. et al.: Gray anatomia. Rio de Janeiro. Gua-nabara Koogan. 37ed., 597 - 603. 1995.

19. BIRNBAUM, K., SIEBERT, C.H., PANDORF, T., SCHOPPHOFF,E., PRESCHER, A. and NIETHARD, F.U.: Anatomical and bio-mechanical investigations of the iliotibial tract. Surg Radiol

Anat., 2004;26(6):433-46.20. DELAGI, E.F. and PEROTTO, A.: Clinical electromyography

of the hand. Arch Phys Med Rehabil,. 1976; 57(2):66-9.21. GARDNER, E., GRAY, D. J. and ORahilly, R.: Anatom ia:

estudo regional do corpo humano. Rio de Janeiro, Guan-abara Koogan 1978.

22. GOODWIN, P.C., KOORTS,K. ,MACK,R. ,MAI. S , MORRISSEY,M.C. and HOOPER, D.M.: Reliability of leg muscle elec-tromyography in vertical jumping. Eur J Appl Physiol., 1999;79:3748.

23. HERNIGOU, P., POIGNARD, A., MATHIEU, G., COHEN, G.,MANICOM, O., and FILIPPINI, P.: Total hip arthroplasty afterfailure of per- and subtrochanteric fracture fixation in elderlysubjects. Rev Chir Orthop Reparatrice Appar Mot., 2006;

92(4):310-5.24. HOFF, J., GRAN, A. and HELGERUD, J.: Maximal strengthtraining improves aerobic endurance performance. Scand JMed Sci Sport., 2002; 12(5):288-95.

25. HOLLINSHEAD, W. H.and ROSSE, C.: Anatomia. 4ed. Rio deJaneiro. Intelivros. 1991.

26. HOUCK, J.: Muscle activation patterns of selected lowerextremity muscles during stepping and cutting tasks. J Elec-tromyogr Kinesiol. 2003;13(6):545-54.

27. JONKERS, I., STEWART, C. and SPAEPEN, A.: The comple-mentary role of the plantarflexors, hamstrings and gluteusmaximus in the control of stance limb stability during gait.Gait and Posture, 2003; 17: 264- 272.

28. LAPLAUD, D., HUG, F. and GRLOT, L.: Reproducibility ofeight lower limb muscles activity level in the course of anincremental pedaling exercise. Journal of Electromyographyand Kinesiology, 2006; 16: 158166.

29. LARSSON, B., KADI, F., LINDVALL, B. and GERDLE, B.: Sur-face electromyography and peak torque of repetitive maxi-mum isokinetic plantar flexions in relation to aspects of mus-cle morphology. Jour Elect Kines, 2006; 16: 281290.

30. LI, L., LANDIN, D., GRODESKY, J. and MYERS, J.: The func-tion of gastrocnemius as a knee flexor at selected knee andankle angles. J Electromyogr Kinesiol. 2002; 12:38590.

31. MAAS, H., BAAN, G.C. and HUIJING, P.A.: Muscle force isdetermined also by muscle relative position: isolated effects.J Biomech. 2004; 1:99110.

32. MOHR, K. J. et al.: Electromyographic of stretching: the effectof warm-up. Clin J Sport Med, 1998; 8, 215 220.

33. MONTE, G.D., ARAMPATZIS, A . , STOGIANNARI, C. and KARA-MANIDIS, K.: In vivo motion transmission in the inactive gas-trocnemius medialis muscletendon unit during ankle and knee

joint rotation. J Electromyogr Kinesiol, 2005; xxx: xxxxxx.34. NEPTUNE, R.R.,ZAJAC, F.E., and KAUTZ, S.A.: Muscle force

redistributes segmental power for body progression duringwalking. Gait and Posture, 2004; 19: 194205.

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35. NYLAND, J., KUZEMCHEK,S . ,PARKS, M. , CABORN, D.N.M.:Femoral anteversion influences vastus medialis and gluteusmedius EMG amplitude: composite hip abductor EMGamplitude ratios during isometric combined hip abduction-external rotation. J Electromyogr Kinesiol 2004; 14: 255261.

36. SADEGHI, H., SADEGHI, S., PRINCE., ALLARD. P., LABELLE,H. and VAUGHAN, C.L.: Functional roles of ankle and hipsagittal muscle moments in able-bodied gait. Clin Biomech,2001; 16:68895.

37. SANDERSON,D.,MARTIN, P.E., HONEYMAN, G. and KEEFER,J.: Gastrocnemius and soleus muscle length, velocity, andEMG responses to changes in pedalling cadence. Journal ofElectromyography and Kinesiology, 2006 (in preparation).

38. STEWART, C., POSTANS, N., SCHWARTZ, MH., ROZUMALSKI,A. and ROBERTS, A.: An exploration of the function of thetriceps surae during normal gait using functional electricalstimulation. Gait Posture. 2007 Jan 12; [Epub ahead of print]

39. Tassi N et al. Electromyographic behaviour of the gastroc-nemius muscle during knee extension and flexion performedon the Leg press. Electromyography and Clinical Neurophisi-ology, 1999; 39: 367377.

40. TASSI, N. and GONCALVES, M.: Electromyographic valida-tion of the double pulley equipment during movements ofthe lower limbs. Electromyogr Clin Neurophysiol, 2002;42(8):473-80.

41. TSCHARNER, V.V. and GOEPFERT, B.: Estimation of the inter-play between groups of fast and slow muscle fibers of the tib-ialis anterior and gastrocnemius muscle while running. Jour-nal of Electromyography and Kinesiology, 2006; 16: 188197.

42. WILLIAMS, P. L. et al.: Gray anatomia. Rio de Janeiro. Gua-

nabara Koogan. 37ed., 597 - 603. 1995.

Address reprint requests to:

Dr. Nadir TassiAv. Hygino Muzzi Filho, 737

Campus Universitrio, MarliaCEP: 17.525-900, So Paulo, Brasil.

Tel: (55) (14) 3402-1372Fax: (55) (14) 3422-4797, E-mail: [email protected]

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703_emg Trabalho Publicado Nadir Vitor