I have been doing the couch-to-5k since late August, and until this week, I was doing very well on it. This last Monday, 3 October, was day 1 of week six. I did that run successfully, but when Wednesday came around, I could barely run. It was as if someone switched off my energy supply. It's Saturday now, and I have not been able to recover my previous stamina. I'm not starving myself. I've lost 11 pounds since the end of August, which is very sensible. I'm drinking water (I don't drink alcohol) and eating healthy meals. I'm having some allergy issues, but I can't imagine that would rob me of my stamina. All I can say is Monday I could run 3/4 of a mile, walk 1/4 mile, then run another 3/4 of a mile. Now I can't. Nothing hurts, I'm not having trouble breathing -- I just lost my energy. Help!
Some allergy medicines do that to me, plus your body's reaction to the allergies can make it harder to run.
Personally I would consider 11 pounds in a month to be a lot, but that is partly relative to your weight and your conditioning. Even so, I don't think that would have such a sudden effect.
Thanks both of you. I did a weeklong survey of my diet, with an Ipad App, and found I've been way under with both carbs and protein. I adjusted my diet to take in more carbs, potassium, and protein, and a week later I was back to normal! I also drink gatorade before and after running.
I might be low in iron; I'm a vegetarian. I'll have to watch out for that.