There are so many ups and downs of a typical training cycle. Two weeks ago, I was flying high, hitting my numbers and ran the “easiest” 20 miler I’ve ever run. This week, I’m quite literally sinking in the pool. My butt is dragging.
I swam this morning and should currently be on the treadmill knocking out my tempo run. But I’m stalling. Trying to figure out if I should run or not. Of course, I’m going to run but should I try for the tempo pace? That is the question. I’m tired and well, I have an angry hamstring that popped up out of nowhere. 
To be honest, I expected to be fresh this week. I had 3 forced rest days (SAT, SUN & MON) because the little guy was in the hospital with pneumonia. He is doing much better now. Still weak but improving every day. His biggest complaint at this point is that his back hurts (from the hospital bed, or maybe the pneumonia?) and that he can’t run as fast as he used to before he got sick. Give it some time, Buddy. Just a little time. As for myself, I’m guessing that hanging out with the little guy in the hospital and being stressed/worried about him was probably more daunting on my mind and body than I realized. I’m back on schedule & trying to follow my plan. I expected to knock out one more killer week before pulling back next week to recharge for the Rock N Roll New Orleans Marathon on 2/28. But alas, I’m just tired. And my back hurts too! And one of my hamstrings is on strike. So I’m just slogging thru the week. Not pushing at all. I’m trying to focus on getting some extra rest, making sure I get extra nutrients, and hoping that I’ll bounce back next week while I’m “tapering” for RNRNOLA.
It’s important to realize that events in our lives effect our bodies. A stress reaction is real. Stress takes a toll on the mind and body. You might feel fatigued, get sick, have stomach issues or stress eat (that’s me!). Long term stress can do some serious damage if we are unable to manage it properly. Please see the awesome graphic below from Life Advantage. Go HERE to see the full article on how stress can effect the body.
Bottom line, give yourself a break when your body is rebelling. Look at what’s happened in life for the last couple weeks if something “new” has popped up. Don’t stress about not feeling great. Just focus on what you can do to improve the situation. Sleep and making sure you get lots of fruits & veggies to up the nutrients in your body is so important. Drink lots of water to flush all the toxins. Avoid caffeine & alcohol. Exercise. Don’t push hard on the workouts but get the blood flowing and you’ll be back to normal before you know it.
** Cheers – Amanda – TooTallFritz **
TooTallFritz 
Your smart if you keep close tabs on this. Stress is stress…whether it comes from the physical workouts or psychological or other aspects of life..increased cortisol levels. Perhaps that week you nailed that 20-miler feeling great…you now incurring some back-log effects, or perhaps the stress from that heavy week confounded with additional stress from the little man’s illness.
You are probably answering the question yourself, regarding feeling as you do, trying to nail that tempo run pace down. I would think you might want to take a pass on that…reduce the overall training volume this week and tone down intensity. Running in some form, even as beat as you feel, could be beneficial….just keep it really low-aerobic/low-intensity….just good enough to get that HR up and get the blood circulating…and the duration long enough to promote clearance of cellular breakdown products or other “toxins” bogging you down. At least 30-min duration at real easy effort, better yet 45-min to not more than 1-hr.
If done correctly and performed at proper low-aerobic intensity…you should feel better than when you started. Build on that with making sure you get healthy nutrition and extra rest…or with that marathon coming up…just focus on taper and with the reduced training volume and balanced mix of both easy and pace runs, should feel the recovery within a few weeks and be “chomping at your bit” to run that marathon!
Good luck….post on how you fare as you work through this bout of fatigue!