Friday, July 14, 2017

And then there were two? Magnesium, cortisol, insomnia, and athletes

I have been having trouble sleeping.  I first had insomnia for 18 days in April.  It was the worst experience of my life with any kind of illness; the mental trauma of being utterly exhausted but unable to sleep, every single night without respite, was worse than anything I've ever experienced with physical injuries, including having to take 9 months off of running for an ankle injury.  So when the insomnia reappeared in late June, I knew I had to get it resolved as soon as possible.

Google searches for athletes' personal experiences with insomnia brought me the horror stories of Bobby Curtis and Tera Moody (don't click on those links if you think your insomnia might be made worse by anxiety about not sleeping!) but other than that, the sum total of anecdotal information was essentially a few forum posts by athletes saying they were having trouble sleeping and wondering if anyone else had had the same issue.  There were virtually never any real answers or any follow-up from the athletes themselves.  Relevant journal articles are out there, but they took a fair bit of time to collate into anything useful.

Given the difficulty I had finding information on the subject, I thought I'd provide some details on what happened with my insomnia and what I've learned along the way, in the hopes that this will be useful to someone else going through the same struggle.

My insomnia

I had what is apparently termed sleep maintenance insomnia.  I could fall asleep easily at bedtime but I would wake up about 4 hours later.  As the April period of insomnia wore on, this got worse and I started waking up only 2 to 3 hours after going to sleep.  When I woke up I would feel almost instantly wide awake and my heart rate would be racing.  If I managed to relax, I would sometimes start feeling sleepy again in about an hour, but absolutely nothing, including the sleeping pills that I eventually tried, would get me to actually fall back asleep.


There is maybe no way to make this part *not* super boring, but I think a few things about the timing of the insomnia may be relevant, so here goes...

--April:  Training block with lots of hillwork in and around Atlanta. Mostly went really well.

April 4 and 5--training diary says I felt awful and took two days off

April 8--first night of insomnia, which would continue every night until April 26ish

April 8 and 9--did two hard runs; felt fine

April 9 to 21--ran very little as the insomnia got worse and worse

April 22--raced a hilly 50k

April 23--overseas flight

April 24--slept 7 hours (sleeping pill aided...) after being awake for 36 hours

April 26--first night of truly normal sleep

Month of May--normal sleep; bits of hard training in cooler climate interspersed with having a sinus infection and not being able to run

May 26--hard 24 hour run in the mountains

May 27 to June 23--sinus infection; didn't run at all except for a couple of 10-20 minute jogs

June 26--started training again with a VERY easy week, although I was in Atlanta and it was about 90 degrees every day.

June 30--first night of Round 2 insomnia

July 1 and 2--only managed 4 hours of sleep

July 3--started taking magnesium supplements (more info below); also stayed up all night to try to force better sleep the night after

July 4-6--normal sleep but took diphenhydramine at bedtime

July 7 and onwards (so far!)--basically normal sleep without any diphenhydramine, although I do still tend to wake up once for a couple of minutes in the middle of the night.

Treatments I tried on round 1 (April, 18 days til normal sleep returned)

In no particular order:

-No caffeine the entire period, including cutting out chocolate
-No computer use after dinner
-Blackout curtains for the bedroom
-After waking up in the middle of the night, getting out of bed and doing some mindless task.  Only worked once, on day 16.
-After waking up in the middle of the night, staying in bed and trying to relax, including listening to talks or meditation podcasts.  Never worked.
-Melatonin, which I had only used about twice in my life previously, both at bedtime and after waking up in the middle of the night.  This did actually work on one night--I woke up in the middle of the night, took 3(?) mg melatonin, and got back to sleep and slept for one hour after taking it.  It didn't work any of the other times I tried it.
-5-hydroxyryptophan at bedtime
-"Lightweight" sleeping pills with the antihistamine diphenhydramine, which is possibly not detrimental to sleep quality, after waking up in the middle of the night.  Made me extremely sleepy but I couldn't fall asleep.
-Days 12 and 13:  600mg of phosphatidyl serine (a phospholipid which potentially lowers cortisol) about an hour before bedtime.  Didn't work on either of these two nights.
-Days 14-18 and onward for another week:  300mg of phosphatidyl serine about an hour before bedtime; dosage lowered after I read a study suggesting any potential effect wouldn't happen if the dosage were too high.  Didn't help on days 14 to 18 but perhaps the cumulative effect of taking it since day 12 finally kicked in on day 18...??
-Days 14-18 and onward for another week:  200 to 300 mg per day of magnesium supplement in the form of a dimagnesium malate tablet.  Didn't help on days 14 to 18 but potential cumulative effect??

Treatments I tried on round 2 (June/July; 5 to 7 days til normal sleep returned)

-Starting on day 2, magnesium supplementation.  About 200mg a day of powdered magnesium citrate and another 200mg of dimagnesium malate tablet (hedging my bets!)
-Also starting on day 2, 300mg of phosphatidyl serine one hour before bedtime

I should also say, I didn't cut back on running at all during round 2.  In fact I increased my training load slightly.

So, what's going on?

The fact that I was able to see much more rapid improvement to the insomnia on round 2 while simultaneously maintaining or increasing my training load suggests that overtraining is not the cause.

It's also looking like psychological stress is not the cause.  In April, my insomnia didn't go away once I had run the race I was training for.  It also didn't come back when my big May event approached.  And in June, when it did come back, I was in a fairly low-stress period with no races at all in the near future.

Another thing that stands out to me is that this is now two rounds of insomnia which went away 4 to 6 days after I started taking both phosphatidyl serine and magnesium.  This could be a total coincidence, or it could be a placebo effect, or it could mean that one or both of these were the cause of the improvement.  Without much other information to go on, it has made me move magnesium deficiency or wonky nighttime cortisol (either rising too early in the nighttime or rising too high) into position as the two prime suspects.  Magnesium deficiency in particular makes an interesting candidate since it could also explain why it took my body two months to kill off a relatively minor respiratory infection (magnesium deficiency may amplify decreased immune responses induced by strenuous exercise) this May and June.  

Why it might be magnesium deficiency

When I first considered magnesium deficiency as a possible cause of my insomnia, I wasn't too convinced.  Magnesium deficiency is very common in the US population as a whole, but my diet is full of magnesium-rich foods--I eat a lot of leafy greens, oats, fish, and dark chocolate--and hardly any processed food. I figured that if anyone were going to be deficient in magnesium, it probably wouldn't be me.

I changed my mind on this after doing some reading.  First, there are many reasons why people in general can be deficient despite getting a sufficient amount of dietary magnesium.  The interaction with other minerals, such as calcium, can decrease absorption.  Gut inflammation or other gut problems can also decrease absorption.  You, or specifically your kidneys, can also be guilty of magnesium wasting.

Second are several athlete-specific factors.  There is some evidence that prolonged endurance exercise increases the body's magnesium requirement.  This may be due to increased sweat and urinary losses.  In particular, large amounts of magnesium may be lost when exercising in a hot and humid environment.  I live in Atlanta...  Second, athletes participating in sports that require weight control often consume less than even the recommended daily allowance of magnesium, which itself is most likely too low for the general population, not to mention for athletes.  So...prolonged endurance exercise, running in a hot and humid environment, and dieting?  Sounds a bit familiar!

But does magnesium deficiency lead to insomnia?  It's commonly said that it does, although I don't think the actual evidence of a connection between the two is amazingly strong.  However, it is definitely looking possible that one exists.

In one study, magnesium supplementation was associated with statistically significant increases in sleep time and with marginal improvement of early morning awakening.  One possible mechanism for a connection between magnesium and insomnia is that magnesium is an essential cofactor for the activation of tryptophan hydrolase and for the binding of serotonin to its receptor.  In at least one study, in healthy individuals there was a positive correlation between platelet magnesium and serotonin concentrations (this was not the case for patients with depression).  There is also the suggestion that magnesium plays a role in sleep regulation through its function as an agonist of gamma-Aminobutyric acid (GABA), which is involved in sleep.

Unfortunately it's not an easy proposition to simply get tested for magnesium deficiency.  The most common version of the test is a serum magnesium test, but since only about 1% of the body's magnesium stores are found in serum and red blood cells, the magnesium content of these is often not representative of total magnesium status. There is a magnesium retention test, which tracks changes in serum magnesium and excretion following oral loading of magnesium, but one researcher notes that this test is lacking in standardization, plus it appears to me that the results would be affected by anything that causes your kidneys to waste magnesium.

At this point, if I had to place a bet with only the information I have, it would be on magnesium deficiency as the cause of my insomnia.  If I were allowed two guesses as to the cause, they would be magnesium deficiency or wonky cortisol.  I'm not willing to risk losing any more sleep by taking only the magnesium supplement or only the phosphatidyl serine next time this happens, sorry!  If I ever end up with any reason to think that neither of these were the cause and that the real cause was Option C, I'll update this blog.  Though I *really* hope I never have the need to investigate any further...