Week 15: A great start the week, but a fizzle at the end

After a lazy weekend, I started the week with a long trail run.  I have been meaning to follow the route of the "Tour de hameaux", which is around 15km.  This circular route rises very steeply, before dropping down rising again, and finally dropping back to the starting point; an elevation of nearly 800m.  Every August this route is the backdrop for a walk organised by the village council.  There are stops in hamlets with food, drink and music.  It is a very pleasant day out.  Unfortunately for me I was alone and nobody was waiting at refreshment stations.
The morning was cold, but I soon warmed up as I jogged to the bottom of the first climb.  I was quickly forced to a fast walk by the steep incline.  The path was very muddy and slippery, especially around a leaking water reservoir built into the hillside.  The first part of the route is on the north facing side of the hill, or "ubac" as they call it here in the Alps.  I could see the sun shining on the hillside on the "adret" (south facing side) of the valley, this motivated me as the last half of the route passed here.  I reached the first village in good time and the route drop down, before following the contour of the valley through a field that showed evidence of cattle.  I crossed my fingers there were no bulls as I dodged large cowpats.  Could the size and shape indicate if the cattle were male or female?   I exited the field without incident except for soaked and muddy shoes, only to be chased by an enthusiastic sheepdog.  Luckily the owner was with him and assured me the dog was only signaling my presence.  The route dropped away to cross the stream that has cut the valley, before rising steeply onto the other side and the sun.
I was feeling pretty good as I ran down the hill to the bridge over the stream.   Unfortunately I had not remembered to concentrate on my feet and slipped in the mud.  I was lucky to maintain my balance but could have easily taken a tumble.  I refocused my attention on placing my feet.  As the path rose again, I  felt as if I was moving quite quickly and my legs felt fine.  After and hour and a half I arrived at the highest point and began my descent back to home.  The sky was clear and I had a spectacular view over my village, the town reservoir and the snow capped mountains in the distance.  I could just make out the tip of Mont Blanc on the Horizon.  I flew down the final part of the slope and powered home the last 500m.  A great way to start the week.
Day two back to the gym again.  Thirty minutes of static bike and weight lifting for core strength.  Still no hamam for my poor muscles.
Unfortunately the next couple of days saw me laid low with a stomach bug.  I toyed with pulling on my running kit and trying to run myself better but I really didn't feel up to it.  How and when to get back into the running shoes after being sick?