**4. Conclusion**

Computational Intelligence in Electromyography Analysis – 60 A Perspective on Current Applications and Future Challenges

**Figure 5.** Relationship, adjust and parameter nonlinear of RMS-sEMG value. ST example.

**Figure 6.** Relationship, adjust and parameter nonlinear of RMS-sEMG value. SM example.

Investigations have been concerned in the restricted use of the isometric contraction ramp during a single, non-fatiguing, and linearly increasing contraction force variation at short intervals, it is suggested that where the isometric ramp contractions can provide higher resolution in the entire spectrum force, less time required for data acquisition electromyography, and less susceptible to fatigue than contractions step. It is possible, however, that whereas the ramp and contraction power spectrum characteristic of the control strategies can incorporate various engine and comparing the dynamic and isometric contractions isokinetic step.

This present study revealed that the relationship between electromyography, force and time has characteristic sigmoidal. This demonstrates that the initial charges in a relationship are slowly increasing, but at intermediate loads this increase is more rapid and exponential. However, this behavior the load end presents a decrease in the rate of increase and maintenance of a depolarization of motor units at the end of execution of the isometric ramp contraction.

This sigmoidal relationship data is well described in the equation proposed for modeling (curve fitting) of hamstring muscle electromyographic signal analyzed, which is presented the start point (*A1*), the constant in equation (*dx*), the turning point the concavity of the curve (*x0*) and peak (*A2*) to be kept in mathematical adjustment of the curve in relation to actual curve acquired.

In summary, the results of this study indicate that RMS values of the hamstrings muscles tend to increase nonlinear whereas force with the number of isometric ramp contractions performed.
