It is amazing how fast you can lose the tone or strength or momentum in some task or exercise if you miss a time of two (or several) in a routine that may even have become habit to you.  I am speaking specifically of my daily exercise routine that I have been faithful to now for years of an hour a day (6 days a week).  Lately as my push up routine has gotten more I have felt less of a need to do that hour work out.  I figure that being active as I can all day long on the simple things helps make up for it too.  If I have copies to make I will get up for each one rather then wait to get up for several.  Also, going up and down the stairs does add 4 seconds to the average life span, so I add an extra minute or 2 every day. (!)
On a day like today when I am busy from the time I get in to the office virtually all day long I figure I keep the engine revving all of the time.  I used up so much energy that when I finally finished the work I had to do I simply crashed for a while and just enjoyed the moment not even thinking.  It felt really good.  It also felt good to force myself into my full hour of exercise from 7-8, so in all facets I count my day has productive.  Sheila hasn't felt quite as chipper.  She has something and feels a little under the weather, but she says that she will still be up at 4, and off to the temple in the morning.   Me, I will sleep a little longer but feel blessed to have another day to enjoy my journey and hopefully accomplish something worthwhile.