Hi, I apply what is called RBT or Rest Based Training. Essentially you would run your sprint all out at 100% effort (of course after warm up properly). You stop running when you no longer can maintain that 90-100% effect. Then walk or jog till you have caught your breath. Basically, you push till can’t and you rest till can. =)
You have many ideas here. I agree that it depends on your goal… how far to run sprint intervals.
I personally started enjoying tabata training: 20 seconds at sprint, 10 seconds to recover, repeated 8 times. Keep track (no pun intended) of your sprint distances and stride in a log to check on your improvements.
Go ahead and have fun mixing up your training with all the ideas you received.
Good luck and enjoy.
Jared, it really is about what you are trying to attain. You have to think about the time of the run and the effect it is having on your body/energy systems. If you do a 10-15sec sprint at top speed you are using your body’s powerful energy molecule in Creatine and you will be developing your TYPE 2 muscle fibers. These are explosive and larger than TYPE 1 slow twitch fibers. You are even developing muscle with this short of a sprint. I would typically go with a work to rest ratio of 1:3 or 4. So, 15sec sprint/45 sec walking. This is also the best way to burn high amounts of calories. Your body really can not be at full speed in a sprint for more than about 10-15 secs. After that period you are burning carbs and are going for more endurance.
Chris Baietto, CSCS, ACE
/Agree for above posts, but you can do intervals for much longer. Its all on what you have trained your body to withstand.
In training for marathons or triathlons, may people simply go for distance and neglect strength/speed training. A favorite of mine is ladder runs. Jog for 2 min, sprint for 2, 3 jog, 3 sprint, up to as much as you can withstand (usually 5-8) then ladder back down.
You get the speed and constitution. Its about getting your body used to the fatigued state.