Sleep and spirituality

In the light of current medical knowledge I keep finding myself looking askance at the reports of what was considered to be heroic dedication to ascetic discipline. And indeed, if the reports are right, it was. However, sometimes I wonder what the cost was. Take this report on the effects of sleep deprivation and think about the ascetic lionising of sleep deprivation as an aid to spiritual devotion.

Lack of sleep has long been connected with reduced ability to concentrate, trouble learning, decreased attention to detail and increased risk of motor vehicle accidents. More recent studies have tied chronic partial sleep deprivation to medical problems, including obesity, diabetes and hypertension.

You see, it looks to me more like someone who does vigils a lot, unless they sleep at other times is actually making themselves less charitable and 'useful' to their neighbours and to God's mission. It does seem to me that we have a primary duty of self-care in pursuing a spiritual path, not so that we pander ourselves and become narcissistic, but so that we can give our best care and worship to God and neighbour and to fulfil with our best efforts our vocations. Only in a personal context of good self care can we then, from time to time think about some of the exercises in asceticism that are implicitly commended by the lives of some saints. Part of the doing of them should be perhaps to count the cost of doing them in terms of the things that they may get in the way of us doing for God and neighbour, and planning to be away from company where our lack of consequent self-restraint or whatever will be less injurious to others ... ?
ScienceDaily: New Study Shows People Sleep Even Less Than They Think:
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