It is important that this doesn't
turn into "junk miles". The aim is not to work hard, just to
put mileage in the "bank", but to clear out waste products. Even
for very long distance runners we'd suggest no more than 2-3 miles for
a recovery run. Long distance runners can get into the mentality of thinking
more miles is always better training - and use "recovery" runs to achieve this.
This is not a good idea and will not result in improved performance.
Sometimes long distance runners, in particular,
find it useful to jog in between hard runs in
an interval session in order to keep moving and
so avoid having muscles stiffen up. This kind of running is
very slow and can even be done on the spot.
You should not confuse this
with Fartlek Training where the
slower paced running is part of the session to work the lactate shuttle
system.