Methodology for obtaining kayak technique using a motion analysis system

Abstract

Movement analysis is known as the qualitative assessment of the musculoskeletal system during

the execution of a motor task. This kind of analysis allows to define the technique of sports motor

tasks. In this study we used a stereophotogrammetry camera system and surface electromyography

on a healthy novice subject to describe her kayak paddling technique. We placed 14 mm reflective

markers, and sEMG on six muscles of the upper body, and performed a manual muscle testing for each

muscle before the trial. The subject performed the kayak paddle technique on a kayak ergometer, we

recorded 45 seconds in the middle of a 10-minute dynamic trial. The data processing for the kinematic

data consisted in: reconstructing the biomechanical model; filling the gaps of the trajectory; defining

events of the motor task; calculating the range of motion of the joints. While the processing of the

sEMG data consisted of obtaining the envelope and the definition of «on» and «off» of each muscle.

The results show the paddle trajectory, the definition of muscle activation based on the on/off, the

percentage of muscle activation, the range of motion for the joints. As the results show we were able

to determine the kayak paddling technique and compare it to what has been previously published,

i.e., the subject measured showed a shoulder rotation that is different to what has previously been

reported in novice subjects, on the other hand the muscle activation of the dorsal and upper trapezius

is similar to what has previously been reported.