I have unfortunately been experiencing a painful back spasm this week which means I have been out of action (no walking) since I returned from the UK on Sunday. This has not been helped by teaching dance on Monday for several hours, but other than that I have had a sedentary few days teaching Psychology and Sociology, talking to online students and writing essays. One student was preparing some research on the topic of body clocks and exercise and there was a BBC program on this theme this evening, so it is very much in my mind.

Since I have been monitoring my fitness daily since May and done what I consider to be a ridiculous amount of fitness activity and intensity minutes, averaging about 5-7 miles of walking every single day and in addition averaging 210 i.m. per week as well as doing other fitness classes, I am aware of significant changes in my body clock, my mental health and in the way I sleep. Most of the time I feel great, I have finally started to lose a little weight though sadly very little 😦 , I eat less and I have a lot of energy.

I should say I am not an early bird, but then neither am I a night owl, but there has been a shift. First of all, I wake up now at dawn and feel relatively ready for the day – not necessarily for a jog, but I am awake and alert. I could easily do some mental work and often do. My body doesn’t seem to wake up fully and I can be quite sluggish if I have to have physical exercise until about 11am (as I found out in Mallorca) and then I can keep going all day, uphill, down dale, wherever or however long my walk or exercise takes me. I am usually out for a maximum of 4 hours, mostly over lunchtime. It is as if a switch goes on, the effect is so dramatic sometimes, especially if it is accompanied by a little food or drink. However, I think it is no coincidence that I am out in the fresh air when the amount and intensity of light at its greatest, especially during the summer and this is having a long-term effect on my circadian rhythms, so I am more active in the day and sleep better at night.

I have never liked exercising in the evening, say after 6.30pm, but I do find tea-time is a great time for muscular strength and flexibility work such as Pilates or Yoga. The body is warmed up through general movement during the day and hormones such as cortisol (stress hormone) are at their lowest so this is a good time to stretch out your body.  As darkness ensues the hormone melatonin increases to encourage you to sleep, which all sounds very sensible. When I had my dance school, I taught ballroom dancing most nights finishing about 10pm, so I didn’t experience the onset of darkness or relaxation until very late so my hormones didn’t kick in at the usual time. Not only was I very active all evening but the lights in the hall were bright, especially in winter; I had to eat at strange times and I found it impossible to sleep before midnight when I got home. I didn’t get up at dawn when I had that life. I used to complain to my doctor at Blisworth that I was always tired, but he dismissed me out of hand, as I always looked so well, and of course in every other way, I was very well and extremely fit, just very tired!!

I have also found that I have started going to bed earlier, about 9.30pm when I can. This means I actually get more sleep cycles, even if I lie awake for some time in the early hours. I think few people have problems with restorative sleep as that occurs predominantly in the first sleep cycles, but I am certain that in the past I have not had enough REM sleep, and when I have been zonked out from a lack of sleep I do notice that I dream more and for longer, and I always feel better for catching up this type of sleep. The length of dreaming sleep takes up a much larger proportion of a sleep cycle as the night goes on, and it is thought that this allows consolidation of memories, which may account for why I have such as lousy memory 😉

This week I have barely been out of the house and I do feel that my new healthy pattern is being disrupted. I have been surrounded by grey light all day as the days are getting shorter and there has been no sun, and the lack of physical activity is making me feel groggy and it is affecting my sleep. As you can see I am awake now at midnight, when I would normally be asleep.

This makes me think of those people with chronic fatigue and other disabling illnesses which prevent them from being active or getting outside. I wonder what happens to their various body clocks when are unable to get out and about. I suffered from a long term illness for 5 years; I learnt to live with morning tiredness but I would make sure I went out for an hour or two each day, no matter how painful or difficult it was. Maybe I did myself a favour that I didn’t fully appreciate at the time. My concern was about losing muscle strength but maybe it also improved my sleep.

So for me, increasing my exercise and exercising late morning to early afternoon has had a significant impact on my sleep / wake cycle. This of course, is my story, and I am no expert in this field. Other people will have different but similar stories of how exercise at different times of day affects their sleep and body clocks. I would be interested to know how tennis players and formula 1 drivers cope will the rapid changes of time zones and sleep patterns and still manage to maintain their peak performances. For those with more usual occupations like you and me, some will find it hard to change their work patterns however much they would like to – nurses on shift work with a young family is an example that springs to mind, but it’s good to be aware of how your own body clock works and how to optimise it for good health and wellbeing. If you haven’t seen it, the programme below is well worth watching:

https://www.bbc.co.uk/iplayer/episode/b0bn5ys4/horizon-2018-9-body-clock-what-makes-us-tick

Hopefully I shall be back walking again next week, maybe Tuesday – and normal service will be resumed.