And here’s another form of sleep inducing behaviour that you might wish to try out. You will recall from my last letter, how it is that body temperature drops a whole degree in sleep. But do you know that you can begin to train your body to reduce its temperature in readiness for sleep as follows?
Approximately one hour before retiring, take a hot bath, shower or sauna. (Should you have any kind of medical condition which is in anyway exacerbated by heat then don’t do it; at least not without first consulting your doctor). As you are sitting there in your hot tub (and the hotter the better, within reason·) signals will pass from your body to your brain stem to the effect that you are in danger of dying from heat stroke. The brain stem is the primitive “reptilian” part of the brain, which we all have and which is ‘not too bright’ (if you follow my meaning), It is that part of the brain which contains and operates the first line of control for such basic incoming temperature-related information.
Fortunately, the higher centres of your brain will be fully aware that you have no intention of succumbing to heatstroke; e.g. you can turn on a cold tap, open a window or even vacate the bathroom altogether. Nevertheless – and not being privy to the awareness of the higher centres – the primitive brain will set in motion all the physiological processes associated with extremely high temperatures. This will lead to sweating and the ‘switching on’ of other heat exchange methods and mechanisms operating between the arteries and veins. Then as you depart from the bath or shower or whatever, like the swing of a pendulum, the brain will over-compensate. Body temperature will drop, admittedly not very much, but certainly enough to assist in the promotion of sleep. Individual differences (in metabolic rate, age, the overall time period during which you endured such heat, ambient room temperature etc.) will dictate whether such change will happen in as little as 20 minutes or as much as 45 minutes to an hour. Nevertheless, try it out for a couple of weeks; even keep a log, using your body as a walking ‘laboratory’.
Exercise is another intervention that will facilitate the onset of sleep. As a bonus, regular exercise – in the form of brisk walking for even just 15 minutes a day – has been shown to increase the overall night’s content of the invaluable Delta, or slow wave sleep. Your ability to follow this practice will obviously depend on your physical condition, as well as upon weather conditions etc. Failing access to a brisk daily walk, exercise taken just around the house, including stairs if you have them, especially before retiring, is well worth considering. As always in the event of doubt, discuss with, or even show the relevant paragraphs of this letter to your GP or member of oncology clinic staff. They will be happy to advise you. (C) SB.