Biometrics – Data for April 21st 2009

Please note that the above data was collected during a 24 hour period on April 21st 2009. This gives us a fair representation of how the ice team members' physiology is responding to the incessant cold.

The biometrics data is captured using Equivital monitoring units, also used by the military, first responders, emergency services and those operating in high risk and remote locations. They have been specifically designed to operate in extreme environments. The units have stood up extremely well so far to the rigours of extended polar travel, but some of the methods for capturing data do require explanation.

The first thing to note is that the data above represents three data sets taken during a 24 hour period, which give an idea of how the team’s physiology is adapting on a particular day in this environment; it is not a live feed.

As a project team, we explored the option of live transmissions, and this is certainly possible, using a combination of Bluetooth and Iridium technology. However, such a set-up is particularly power hungry, and given the power limitations imposed on the team (they have to carry all power supplies with them in their sledges), we opted instead to prioritise our power supply elsewhere. Biometric data is still captured into the device’s integral memory every five seconds, but it is not transmitted back to the UK in real time.

Heart Rate and Respiratory Rate

This is recorded on the chest and obviously varies according to the activity conducted by each team member at certain times of the day. The team typically drag their sledges for 75 minutes and then take a 15 minute break, and as a trio they will usually complete six or seven such sessions each day. As such, their breathing rates and heart rates will obviously be higher during skiing sessions than when they sleep.

Occasionally, however, we may see data that does not seem to fit this pattern perfectly. As an example, Pen has a naturally low heart rate when compared to many individuals, which incidentally makes him well suited to long distance polar travel.

Core Temperature and Skin Temperature

There are two methods used for collecting temperature. The first is skin temperature measurement, which is recorded on the chest and varies widely, depending on clothing, activity and environment. The second is core temperature, which is measured using an ingested core temperature pill with an internal radio, which transmits the reading to the Equivital unit. The pill transmits a temperature reading at a set interval. The temperature will be lower when the pill is initially taken and rises during the initial transit of the pill, at which point readings indicative of core are seen.

Readings may also occasionally drop to zero. This can happen if a unit is removed, so that its battery can be replaced, or, in the case of core temperature, if one transmitter pill works its way out of the body’s digestive system and another pill is not immediately swallowed.

An apology

We'd like to apologise to anybody who felt misled by our recent biometric data. The data was initially displayed in error in a way that gave the impression that it was live. The intended qualification and explanation that it was, in fact, delayed information, was at first missing. We have subsequently corrected this with specific information concerning the above data. We apologise for the errors and to anyone who may have found the data misleading.