On the 8th Run Of Christmas...

8x400's

How it's done:

• Warm up with a half mile at 70% effort.
• This is best done on a track. If you don't have access to a track then marking off the distance is ideal.  You should be able to run without looking down too much(watch/phone)
• Run 400m, recover for 90 sec.
• Do this 8 times.  The 400 is a tough 1-3.5 minutes for most of us. 

It's simple but it ain't easy.  Be strict on recovery.  The faster we run, the more efficient our form typically is so keep in mind the end goal is effort and running economy!

See you tomorrow for the 9th day!