Well, it seems my last blog post (which went on about how good my running has been recently, how I'm injury free, and feeling very confident) was a step too far and I tempted fate.
Last night I suffered a really frightening hyponatremia episode after a weekend of doing 21miles on the Saturday and 6 miles on the Sunday, in the August sun.
Hyponatremia is a condition that affects different groups of people, including long distance runners (although usually people at the beginning of their marathon career as more experienced runners tend to know better). The definition from the Wiki page is: "Hyponatremia is an electrolyte disturbance in which the sodium concentration in the serum is lower than normal." Although there are other causes, for runners, essentially it happens when you drink too much plain water and don't sufficiently replace the salt and mineral content that your body has lost through sweating during long runs, resulting in a dilution of the fluids around the body's cells. It's worse when the temperature starts to soar outside because you think you should be drinking more, and, if you're like me, the sweat levels increase too - the dried salt crystals on my face and body after my 21miles on Saturday were a sight to behold.
It's something I have suffered from before, but never as badly as last night. Although on my runs I drank sports drinks which contain electrolytes and so, I thought, would replace what I was losing in sweat, and so stave off hyponatremia, I didn't really eat anything containing salt and didn't add salt to any of my food over the weekend - I grew up in a house where salt was very bad for you and we never had it in the house, never mind on the table! To top it off last night, because I was thirsty, I ended up drinking about 4 pints of squash through Sunday evening. My lack of salt, combined with that extra fluid, pushed my body over the edge...
Come about midnight last night, I went up to get ready for bed. I started to get a headache, which within minutes became incredibly intense, I started to feel nauseous, then dizzy and then faint. As I've had these episodes before (most recently when on holiday in a very hot India) I recognised the symptoms and laid down on the floor before I fell, and think I must have passed out. A short while later I came too and realised how bad I was, and managed to stumble into the bedroom where Francis was. I had started to lose control of my breathing, which was very fast and shallow, and my heart was beating incredibly rapidly. I was disoriented, couldn't open my eyes, and just lay on the bed...oh, and then I started shaking.
The four main causes of death in marathon runners seem to be heart disease, genetic heart defects, heat stoke and hyponatremia - I wondered if this was what was going to be my fate, and as I lay on the bed I was desperately wondering if Francis was going to call am ambulance for me but wasn't able to say anything. It was very, very frightening.
As Francis has seen me through these episodes before, he sensibly didn't call an ambulance but just got me to drink a rehydration solution that we keep in the cupboard, and before too long I was breathing normally, my heart had calmed down, I was feeling a bit better, and, about 40 minutes after it started, I promptly fell asleep.
Although I still feel a bit woozy this morning, I've had another of the rehydration drinks, and am well on the way to recovery. I really mustn't let this happen again - it is a serious condition, and if I don't start to pay as much attention to my hydration and nutrition on a day to day basis as I do during my runs, I really could end up in hospital, in a coma, or worse.....