How long and how fast should your long runs be?  The main
purpose of long runs is to spend time on your feet  Credit:
Allsport UK/Allsport How long should a long run be? Time is a
better gauge than distance.  That is, the goal of a long run is
not to cover a certain distance, but to spend time on your feet.
• Run for at least 1 1/2 to two hours. That's the minimum long
run roughly 10 to 16 miles to maintain a high endurance level.
• Increase your long runs by no more than 15 minutes at a time.
Any more and you're setting yourself up for injury or illness.
• For marathoners, 26 is better than 20. Exercise physiologist
David Martin, Ph.D., says one 26-miler is better than several
20-milers: "Milers run miles in practice, 10K runners run 10Ks,
so why shouldn't marathoners cover their distance in practice,
too?"      Adds 1972 10,000-meter Olympian Jeff Galloway: "Long
runs of 26 miles train the body to do what is required of it
during the event." However, both Galloway and Martin advise
building up to 2