I was looking through some files looking for unrelated info when I stumbled onto a note file I working on in 1993 but never utilized in discussing functional or occupational fitness. Most of the discussions pertinent to gaining and maintaining adequate occupational/functional fitness focus on having adequate physical fitness with much being overlooked about the cognitive and psychological aspects of having adequate or sufficient occupational/functional fitness.
Pertinent to performing duties as a mission ready member of a BA AFSC, adequate or sufficient occupational specific fitness is having the ability to dependably, reliably and successfully getting something done in the physically demanding environment while under duress.
Being successful sufficiently includes getting back from the mission to be ready and available to do the next mission. This requires ability of adaptable Human Orientations which encompasses various inherent psychophysiological patterns.
Orientation may be defined as knowing how, when and where you are. Pertinent information is supplied by all the senses and normally is integrated to provide a conscious state. Accuracy of this will depend on (a) the validity of the information supplied by the senses; (b) the efficiency of the integration process.
Information supplied by special senses can be subject to error due to inherent limitations, principally, (a) Events below a given threshold are not sensed; (b) Qualitative errors can arise due to the operation of Weber's Law. In addition, false integration can normally take place as in coriolis accelerations, altered visual perceptions, etc. Changed physiological states resulting from hypoxia, hyperventilation, positive acceleration, etc., can further alter the normal integration process. Finally, disorientation can itself be disorientating in a feed-back system.
Consider humans do have differing psychophysiological patterns which causes each person to have differences in perceptual thresholds, time estimation ability, and ability to adapt to doing during prolonged period of performance having minimum, if any, opportunities for rest. Further consider the duress of working in an isolated from support and lack of reinforcements/relief shift of getting something accomplished in the remote/isolated mission environment. Consider also dealing with doing in a severe hot or extremely cold environment. These are all concerns of having adequate adaptable human orientation.
Having better than average physical fitness does contribute to improved ability of adaptable Human Orientations.