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Man. Ther., Posturology Rehabil. J. 2017; 15
10.17784/mtprehabjournal.2017.15.529 doi: http://dx.doi.org/10.17784/mtprehabjournal.2017.15.529
Abstract:Background: muscle activation measured by electromyography (EMG) provides additional insight into functional differences between movements and muscle involvement. Objective: to evaluate the EMG of triceps surae during heel-raise exercise in healthy subjects performed at leg press machine with different feet positions. Methods: ten trained healthy male adults aged between 20 and 30 years voluntarily took part in the study. After biometric analyses the EMG signals were obtained using a 8-channel telemeterized surface EMG system (EMG System do Brazil, Brazil Ltda) (amplifier gain: 1000x, common rejection mode ratio >100 dB, band pass filter: 20 to 500 Hz). All data was acquired and processed using a 16-bit analog to digital converter, with a sampling frequency of 2kHz on the soleus (Sol), medial (GM) and lateral (GL) gastrocnemius muscles in both legs, in accordance with the recommendations of SENIAN. The root mean square (RMS) of the EMG amplitude was calculated to evaluate muscle activity of the three muscles. After being properly prepared for eletromyography procedures, all subjects were instructed to perform 3 sets of 5 repetitions during heel-raise exercise using the maximal load that enabled 10 repetitions on leg press 45° machine, each set being performed with one of the following feet positions: neutral (0º), internal and external rotation (both with 45° from neutral position). The tests were sequential and applied a 5-minute rest interval between sets. The order of the tests was randomized. Results: thought had been found interaction (F=0.27, P= 0.75) on RMS parameters and feet position, the values of Sol muscle were significantly (F=17.86, P= 0.003) lower compared with GL and GM muscles independently of feet position. Conclusion: The change in the feet position during the heel-rise exercise performed in the leg press does not influence the activation of the triceps surae, and the soleus is less activated than the gastrocnemius in that exercise.
Keywords:Leg Press, Feet Position, Strength Training, Root Mean Square, Muscle Activity.
1. Aronow MS, Diaz-Doran V, Sullivan RJ, Adams DJ. The effect of triceps surae contracture force on plantar foot pressure distribution. Foot Ankle Int. 2006;27:43-52.
2. Dalmau-Pastor M, Fargues-Polo B Jr, Casanova-Martínez D Jr, Vega J, Golanó P. Anatomy of the triceps surae: a pictorial essay.. Foot Ankle Clin. 2014;19:603-635.
3. Magnusson SP, Aagaard P, Rosager S, Dyhre-Poulsen P, Kjaer M. Loaddisplacement properties of the human triceps surae aponeurosis in vivo. J Physiol. 2001;531:277-288.
4. Rosager S, Aagaard P, Dyhre-Poulsen P, Neergaard K, Kjaer M, Magnusson SP. Load-displacement properties of the human triceps surae aponeurosis and tendon in runners and non-runners. Scand J Med Sci Sports. 2002;12:90-98.
5. Bezodis I, Kerwin D, Salo A. Lower-limb mechanics during the support phase of maximum-velocity sprint running. Med Sci Sports Exerc. 2008;40:707-715.
6. Flanagan S, Song JE, Wang MY, Greendale G, Azen S, Salem G. Biomechanics of the heel-raise exercise. J Aging Phys Activ. 2005;13:160-171.
7. Vilaça-Alves J, Guimarães F, Rosa C, Neves EB, Saavedra FJ, Reis VM. Electromyography analysis of the abdominal crunch In stable and unstable surface. Gazzetta Medica Italiana. 2016;175:189-194.
8. Dorel S, Couturier A, Hug F. Intra-session repeatability of lower limb muscles activation pattern during pedaling. J Electromyogr Kinesiol. 2008;18:857-865.
9. Capaday C, Stein RB. Difference in the amplitude of the human soleus H reflex during walking and running. J Physiol (Land). 1987;392:513-522.
10. Riemann BL, Limbaugh GK, Eitner JD, LeFavi RG. Medial and lateral gastrocnemius activation differences during heel-raise exercise with three different foot positions. J Strength Cond Res. 2011;25:634-639.
11. Freriks B, Hermens HJ. European recommendations for surface electromyography: results of the SENIAM project. Enschede: Roessingh Research and Development; 1999.
12. Cohen J. Statistical power analysis for the behavioral sciences. New York: Academic Press; 1969.
13. Hamill J, Knutzen KM. Biomechanical basis of human movement. 2.ed. Philadelphia: Lippincott Williams and Wilkins; 1995.
14. Ribeiro G, Dionísio VC, Almeida LG. Electromyographic activity during one-legged squatting under different foot positions. Braz J Sports Med. 2007;13:43-46.
15. Baptista MT, Do Nascimento FXM, Nardes LK, Da Matta TT, De Oliveira LF. Influência de posições do joelho no torque e atividade mioelétrica do tríceps sural na flexão plantar isométrica máxima. Rev Bras Educ Fís Esporte. 2014 (inpress).
16. Fiebert I, Spieholz N, Applegate E, Carbone M, Gonzales G, Gorack W. Integrated EMG study of the medial and lateral heads of the gastrocnemius during isometric plantar flexion with varying cuff weights loads. J Back Musculoskel Rehab. 1998;11:19-26.
17. Kawakami Y, Ichinose Y, Fukunaga T. Architectural and functional features of human triceps surae muscles during contraction. J Appl Physiol. 1998;85:398-404.
18. Johnson MA, Polgar J, Weightman D, Appleton D. Data on the distribution of fibre types in thirty-six human muscles: an autopsy study. J Neurol Sci. 1973;18:111-129.