So THIS is why I was running every morning and couldn't get below 22:30
http://www.brianmac.demon.co.uk/vo2max.htm
http://www.coolrunning.com/major/97/training/hampson.html
http://www.brianmac.demon.co.uk/vo2max.htm
http://www.coolrunning.com/major/97/training/hampson.html