As you probably know from [[How Often To Run]] and [[Supercompensation and Why exercise does not make you fit|Supercompensation]], I do not believe short, easy runs are generally beneficial. There is a place for [[Recovery Runs]], but only when you are recovering from [[Delayed Onset Muscle Soreness]] or injury. ==Toxic Miles==I believe that if a run is too short to build endurance, to slow to build aerobic or anaerobic capacity, not hilly enough to build eccentric resistance, then it is toxic. These Toxic Miles do nothing but slow up the recovery from our quality runs, which reduces the intensity we can do these quality runs and make us more injury prone. Some people call these 'junk miles' as they are worthless. I prefer the stronger term, 'Toxic Miles', because I believe that they have a negative impact on our an athlete's training. You can be a successful runner while putting in a lot of Toxic Miles, but they make success much harder to achieve. There is a place for [[Recovery Runs]], but only when you are recovering from [[Delayed Onset Muscle Soreness]] or injury. While the stress of Toxic Miles generally degrades training results, cross training between quality running days can produce benefits. See [[FIRST]].
==Cross Training==While the stress of Toxic Miles generally degrades training results, cross training between quality running days can produce benefits. See [[FIRST]]. ==CounterpointsCounter Arguments==
There are arguments against the 'Toxic Miles' philosophy.
===* '''Clearing the Head=== ''' As Michael M points out, running does bring mental benefits. Not 'mental toughness' so much as a time of peace, freedom, and meditation. ===* '''Calorie Burn===''' The benefit of extra running for weight loss is less clear. The extra calorie burn is likely to be fairly small, but the exercise may improve the muscle's sensitivity to insulin. See [[Nutrient Timing]]. Doing cross training may be more beneficial however. ===* '''Base Miles to Support Quality===''' There is a belief that to perform quality training, you need a base of to do slower milesso 'support' the speedwork. While I can see the value in building up distance endurance before embarking on speedwork, I have found no evidence to support the idea that doing slow running between speedwork sessions is useful.* '''Base Miles to Support Long Runs''' There a similar belief that to perform long runs, you need slower miles as 'support'. I have seen no evidence to support this idea.== See Also ==* [[Golden Rule of Training]]* [[Supercompensation and Why exercise does not make you fit]]* [[Introduction to Workout Types]]* [[Introduction to Interval Training]] and [[Safe Speedwork]]* [[Recovery Runs]]* [[Fartlek]]* [[Walking Breaks]]