Sleep, caffeine, and vacation learnings

Warning: this content is older than 365 days. It may be out of date and no longer relevant.

One of my peculiar habits I do every 6 months or so is to take a week off of any kind of caffeine. This started a few years ago at the suggestion of Barry Meklir, my muscular therapist, who recommended it in order to give the body’s adrenal glands some time to recharge and reset. Consistent high dosages of caffeine tend to mess them up. I found that the caffeine purge was helpful for also getting my sleep cycles back in order, but didn’t give it much thought beyond that.

The signs when it’s time to do a caffeine purge become fairly obvious to me. First, caffeine’s effectiveness begins to decline. If I find myself feeling the need for more than the morning cup of coffee, that’s a hint. When I start drinking too much coffee, I notice other symptoms: little aches and pains become more persistent. Cuts and minor injuries don’t heal as fast. Muscle soreness from workouts lasts longer. When I see those signs, it’s time to do a purge.

Last week, while on vacation, I did one of my semi-annual purges, but the difference this time around was that I was paying closer attention to my sleep using my fitness tracker. I realized that there was a deeper issue than just caffeine – caffeine was just an easy source to blame.

The real source of the problem was the kind of sleep I was getting. My fitness tracker breaks out sleep into three different components: REM sleep (for the brain), light sleep, and deep sleep (for healing the body). How accurate it is, I’m not sure, but because I have only one and I wear it consistently, if it’s inaccurate, it’s consistently inaccurate.

Take a look at this simple chart I made of the three kinds of sleep I’ve gotten over the past three weeks:


Notice that during my vacation, I clocked more sleep (of course) but more importantly, REM sleep and deep sleep about matched each other. They kept pace, meaning that body and mind both had a chance to recover. Now look at the days before vacation. REM sleep was still more or less consistent, but deep sleep took some major, major hits. Some nights, my body had less than 20 minutes of healing time. If there are any injuries or illnesses, that little healing time is a problem, and it compounds on itself. Little injuries can become bigger injuries. A mild cold can become a nasty cold.

(It’s interesting, as a side note, that the mind protects itself more than the body, as evidenced by which kind of sleep gets sacrificed first.)

The solution, besides the week off of caffeine, was to more carefully judge when I could take caffeine into my body and when it needed to be at a low enough level to exit my body. There are a number of excellent apps out there that can track caffeine intake; the one I use on IOS is Caffeine Zone 2.


You have to judge how much caffeine impacts your ability to sleep; if a cup of black tea would keep you from falling asleep easily (55mg) or a can of soda (46mg), then that’s a good benchmark for what has to be out of your bloodstream. If a cup of green tea keeps you from falling asleep (25mg for an 8oz cup) then you know that’s a good benchmark. Once you know how much caffeine disrupts your sleep, you can program it into the app of your choice so that you know when you should have your daily dosages of caffeine.

Here’s some food for thought: if you take a large cup of coffee – 16oz, 240mg of caffeine – it can take up to 24 hours to completely exit your body, and 16 hours before the caffeine in your bloodstream is below that of a cup of green tea. If green tea disrupts your sleep, then having coffee any time sooner than 18 hours before bed is going to make sleep less productive for you.

If you’re trying to deal with any kinds of recovery or healing issues, look to your sleep first: more of it. You might find some answers there.

Disclaimer: I am in no way a qualified medical practitioner of any kind, and what I wrote here should not constitute medical advice. Consult with your physician before making any significant changes to your lifestyle or diet.

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