Hi Ash,
yeah thanks for the response and i understand what you are saying but what i was trying to ask was how do you decide what to do say do 10 x 200m or 15 x 150 or 20 x 100 etc…which works best or should it be 20 x 175m?! The numbers i have used are not exact to what you have prescribed in previous posts but i hope understand what i am asking,
Cheers,
Runner.