Today there are many sports tracking applications, but none of them give the runner feedback
on running technique. The purpose of this study is to do a mapping between input and output in
a sports tracking application that enables sonification. A scheme for sonification is also
presented, but not evaluated. The method corresponds to the design phase of an iterative design
study. The method also includes a survey to give additional information for the choice of
mapping. A good running technique depends on the step length, relaxation, a straight posture,
upright head, unclenched fists, setting the front half of the foot down first upon ground impact,
having ground contact with the foot for long enough,
the runner’s vertical oscillation, the
distance between the projection of runner’s centre of gravity to the ground and where the foot is
set down, the angle at the elbows, that the arms move in counterphase with the legs, the tilt of
the upper body and a slight tilt from the ankle.
To measure running technique, GPS, accelerometers, gyroscopes, barometers, pedometers and
pulse measuring devices can be used. 37 persons answered the survey. Significantly fewer
respondents wanted feedback on their running technique. The mapping is between speed,
combustion, distance and vertical displacement to the accelerometer of the smartphone, route to
the smartphone’s GPS, upright head to a gyroscope, straight posture to the gyroscope of the
smartphone and a gyroscope at the neck, distance between foot impact and projection of the
runner’s centre of gravity to an accelerometer at the foot in combination with the smartphone’s
accelerometer and that the front half of the foot is set down first to two barometers placed by the
toes and the heel.
The suggested scheme for sonification is to alter or add to the music that the runner is listening
to while running. Vertical displacement is sonified by an added
“twang”-sound, the distance
between the projection of runner’s centre of gravity to the ground and where the foot
is set
down is sonified by altering the music with a highpass-filter with varying cutoff-frequency,
straight posture is sonified by a lowpass-filter with varying cutoff-frequency, the tilt of the head
is sonified by the sound of wind added to the music, setting the front half of the foot down first
upon ground impact is sonified by heavy footstep sounds whenever the heel is set down first
and having ground contact with the foot for long enough is sonified by a warning siren
whenever the ground contact is too short.