This paper presents a solution for the inverse kinematics in a human arm kinematics model of seven degrees of freedom applying Genetic Algorithms in the shoulder joint and the Piper method in the whole arm in order to make the algorithm response faster and accurate. The Genetic Algorithm's code explores a set of initial solutions and optimizing it until find an angular response that satisfies the positional and rotational restrictions proposed to the model with a minimal error and a considerably speed. The accuracy and reliability of the applied algorithm is evaluated applying a statistical analysis upon a set of answers using SPSS Statistics.