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Join Date: Jun 2002
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Depends on what you are trying to accomplish.
For general fitness, sprints in the 100-200 meter ranges followed by an equal distance rest will probably provide you the same amount of general fitness as running 3 miles... maybe even in a shorter distance.
Keep the heart rate up for at least 20 minutes 3x a week and you'll gain in general fitness. The nice thing about sprints is they are more likely to cause muscle growth than slow distance (I don't consider 3 miles long.)
The other benefit is most games we still play into adulthood: flag football, baseball, basketball, racquet sports, etc. rely on quick bursts of speed followed by relative low intensity (walking or slow jog.) You are priming your body to do these types of activities.
An example would be... lets say two teams have the same basketball skills (shooting percentage, dribbling abilities, etc.) and one runs 3 miles a day and the other one runs 10x200 sprints every day. I'll drop my money on the one running sprints. The marathon team , while certainly in good marathon shape, hasn't been training their bodies for basketball.
If you are running 3 miles comfortably and doing at no more than 24-27 minutes you probably could do something like this:
1/2 mile warm up
few minutes of stretching out
10x200 (or 10x100) with an equal distance in between (either walking or jogging)
1/2 mile cool down
Work each week at adding a few reps into the program until you get to 15x200 or 20x100 three times a week. At that point you are effectively running 3 miles. If 10x200 or 10x100 is too much at first drop it down and build from there.
Anything less than 100 meters in sprints is using a different set of phsyiological systems and you aren't getting a good taxing of the aerobic system.
Hill repeats lasting 20 seconds or longer (if you have a decent hill around you) are also very good. Sprint up the hill, walk/jog back down the hill. Stadium stairs work as well.
I'm more of a long course triathlon and marathoner trainer so very rarely will my interval training get below 800 meters and more than likely will be at the 1200 meter to 1 mile type of intervals.
I also include hill training as well because of the strength benefits of hill running. Even if the race I'm prepping for doesn't have hills I still do hills because of the strength it gives me towards the waning portions of the race when you have to kick it up a gear.
On hills what I do is a warm up (about 1 mile), 6-8 hill repeats lasting 20-30 seconds, 3 mile tempo run (about 80% full effort), 6-8 hill repeats, 1 mile cool down. I do this about once every two weeks. I don't know how many times the exrta strength has come in handy when I'm at 23-24 miles into a marathon and I can't feel my legs anymore.
Bottom line, what every makes you want to get out and move is what is best for you. Just make sure its at least 20 minutes worth of work!
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