I'm knackered. Bone-achingly weary.
Although my MS means that this is now an ever-present threat hanging over me, I was absolutely fine whilst we were skiing a couple of weeks ago. My upper body strength is now such that I struggle if I'm forced to carry my skis too far, but this year I had no real problems at all with fatigue, in spite of all the extra exertion. I took my pep pills with me and carried them with me out onto the slopes every day, but I never once thought that I might need to take one: my energy levels were fine and I had no real problem with muscle fatigue beyond the expected burning thighs during a long run down the mountain.
Since we've been back, however, it's been a different story, and I've been struggling with weariness and fatigue for much of the last ten days. It was so bad on our first week back that I was finding that my body was simply shutting down by about 10pm and I was forced to go straight to bed before I was entirely unable to move. By 10:30pm most nights, C. would come up to bed and find me entirely dead to the world. It's a horrible feeling when my body shuts down like that: it's almost as though I'm locked in as my muscles entirely fail to respond to my brain's commands. Luckily, if this happens when I'm at home, then I can just go to bed. What worries me is if it happens when I don't have that option. Fortunately, it's not happened yet.
On reflection then, perhaps this wasn't the best time to up my exercise regime.
In spite of my fatigue, I decided that I needed to up the intensity of my running. Perhaps it was all the stodgy food that I ate when skiing (even if I didn't actually put on any weight, in spite of eating like a pig); perhaps it was the thought that I might enter the half marathon this year and maybe also a triathlon or two. Whatever the reason, I felt that the time was right to start to reintroduce interval training into my schedule. I'm usually a very one-paced runner. Over the last few months, I've been focusing on running faster, but there is still very little variation in the pacing of my runs. Interval running is designed to force you to work harder and to build the fast-twitch muscle fibre as you mix timed bursts of faster running into your usual pace. I did some of this in the run up to the half marathon in 2009, some of it on a hill, and it was bloody hard work but I think it was very effective in making me a quicker runner.
This time around, instead of shuttle running from point to point with bursts of two minutes at a steady pace and two minutes of quicker running, I wanted to incorporate the changes of pace into my usual routes. Using the brilliant Runkeeper app on my iPhone that tracks all of my runs, I set up intervals of 5 minutes steady with 2 minutes fast. At the change of each interval, the app beeps to indicate the need to change pace. Simple, but effective. You quickly learn to anticipate the beeps, of course, dreading the beep that signals a faster interval, and then waiting the seemingly impossibly long time before the beep that signals you can slow down again. As ever, interval running is as much a mental exercise as it is physical: time seems to slow down during the quicker intervals, and it takes real concentration to keep picking your knees up as you begin to tire. I try and pick out little intermediate points to focus on instead of thinking about the time: run to that tree; to that bench; to that bush... hopefully bringing you to the point where the next beep signals you can slow down again.
I've done this now two or three times in the last week or so, and it is exhausting. I come in from each run absolutely shattered. On the plus side though, I am running at least 15 seconds per mile faster on average, with my faster intervals clocking in at a pace of about 7 minutes per mile... although I had to wean myself out of the pointless habit of running a little bit faster in my "steady" intervals as I reached the end of a run to try and avoid hitting a "fast" interval before I got home.....
I AM weary at the moment, but whatever toll my MS may be taking on my body, at least I know that some of that fatigue has been earned the old-fashioned way.