Lost My Running Mojo?

Tuesday: First run of the week, interval training - 6 x 3min runs at 10km pace, followed by 2min recovery jogs. Sounded simple enough. A very hot day, I was again dragging myself to get to my run but as usual, once I started my warm-up walk, I was eager to get going. I tried setting my mobile's alarms to go off after each 3min run but this was apparently too complex for the mobile phone, and it was a little time-consuming, so I had to rely on keeping an eye on the time myself. The last few runs were in my loose running bottoms, which are looser than usual (wahey) but make it difficult for running, as I constantly pull them up (grrr), so I was out in my capri pants today. Not a good run, I underestimated how difficult it would be, and underestimated my body today. I had to stop before the 4th interval ended, covering 2.01miles in 19mins 50secs. After 10mins, my body started to slow, I tried to slow down in general in response to feeling faint and dizzy, but it didn't help much. I was stumbling and my eyes were closing, very similar to how I felt during the Great Edinbugh Run :o( I was so disheartened to feel like this but perhaps I was underprepared, in terms of hydration and salt levels. I spent the rest of the day drinking lots of water and upping my salt levels, napping too, to prepare myself for tomorrow. The next run is supposed to be on Thursday but I will be busy all day, sitting on an interview panel, interviewing candidates for receptionist positions. So, tomorrow is a running day, '20mins easy run', but I know I need to do more than that. It sounds strange but have I lost my running mojo? I don't feel as motivated as usual, though I am always keen when I start my run, but I am not running like I used to. I still feel really determined, though, perhaps a lot of runners go through 'dips' like this. After my run, I came home to something that should motivate me further... (to be continued) ... :o)