A TEXTILEBASED WEARABLE SYSTEM FOR THE

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A TEXTILE-BASED WEARABLE SYSTEM FOR THE
ASSESMENT OF CARDIORESPIRATORY SIGNALS IN
ALTERED GRAVITY Merati Giampiero1, Castiglioni
Paolo2, Veicsteinas Arsenio3, Di Rienzo Marco2
(Don C. Gnocchi Foundation and Universtity of
Milan1, Don C. Gnocchi Foundation2, University of
Milan3, Italy) In many sport specialties,
gravitational or centrifugal forces may
importantly interfere with physiological
functions. We realised a new wearable system,
based on textile technol-ogy, for the assessment
of cardiorespiratory signals and ac-celerations
in sport and work activities performed in altered
gravity, through uninterrupted long-term
recordings (up to 28 hours), with no interference
with the subjects behaviour. The system, named
MagIC, consists of a vest made of cot-ton and
lycra embedding two textile ECG electrodes, a
tex-tile piezoresistive transducer for measuring
the respiratory frequency, and two small 3D MEMS
accelerometers for as-sessing the subjects
movements and a seismocardiogram (i.e., the
recording of body vibrations due to the heart
beat). Sensors are connected to a small
electronic module placed on the vest which
digitalizes signals at 150 Hz, stores data on a
memory card and/or wireless transmits them to an
ex-ternal PDA. The system has been previously
tested on cardiac patients and healthy subjects
during daily life activities. In this study we
tested the capability of the system to quantify
effects of gravitational stress on the
cardiovascular dynamics dur-ing parabolic flights
and parachute jumps. Parabolic flights were
studied in two subjects during a 75 min. flight
on board of a modified Boeing 727-200 aircraft.
The flight consisted of one parabola at 0.36g,
four at 0.16g and ten at 0g. The 0g parabolas
were preceded and followed by 1.8g
accelerations. The system transmitted ECG and
ac-celerometric data to the PDA without signal
loss during the whole flight, with adequate
quality to derive a complete tachogram, identify
ectopic beats, and correlate heart rate changes
with changes of acceleration. We also tested the
system by monitoring a parachutist before, during
and after a jump. The recording included a 20 min
flight, the jump from 4800 m, the phase of the
parachute opening, after 1 min of free fall, and
landing at see level, 2.5 min after the jump.
Also in this test the system recorded the ECG
contin-uously, allowing the evaluation of links
between heart rate and gravitational changes
occurring during the three major phases of the
jump free-fall, parachute opening, and land-ing.
In both the applications, the comfort of the
system was high and the vest never interfered
with the subjects activi-ties, even during the
acrobatic manoeuvres in the free-fall phase of
the parachute jump. In conclusion, our wearable
system was found to be ade-quate to investigate
heart rate dynamics under gravitational stress
even for long periods. These results support the
use of textile technology in systems for
monitoring vital signs in sport and work
activities in extreme environments. Keywords
Physiology 12thAnnual Congress of the ECSS,
1114 July 2007, Jyväskylä, Finland I