Day of Rest

'Benefits of day of rest' is a search topic in Google.  Research is confirming what religion has known since the beginning of time. 
Genesis 2:2

And on the seventh day God ended his work which he had made; and he rested on the seventh day from all his work which he had made. (KJV)

Sports perspective
http://sportsmedicine.about.com/od/sampleworkouts/a/RestandRecovery.htm
http://www.runnersworld.com/running-tips/rest-easy

Health perspective
http://www.lhj.com/health/stress/relaxation-techniques/the-benefits-of-relaxation/

Weight perspective
http://wiki.answers.com/Q/Do_rest_days_help_your_overall_workouts_and_fat_burning
 I discovered for myself that is after a day of rest that I am most likely to register weight loss on the scales. 

I am very enthusiastic for resting.  I get tired easily.  However, one of the things that I needed to learn was resting came after the work.  Resting on top of resting I actually ended up more tired and less rested after sleeping.  I spent almost 3 years in bed with no end in sight.  I started with baby steps.  Adding a bit more everyday.  Sunday was my hardest day when I attended church and wanted to prepare a fancy meal for dinner.  Fortunately, DH persuaded me to fix waffles for dinner.  Fast, simple and gave me a break.  The need for a balance between resting and working is now accepted on every front.  Scientists are accepting that God knew the value of resting after work.