Running, sprints?

Question

I am a long distance runner and training for the half mile. Today I ran 3 miles in 25 minutes then after cooling down for 5, I ran 5 x 100. My problem is after about 80 meters or so I tend to slow down, like I have no energy. Are my muscles not cooperating because I'm tired? Or is there is a certain work out to improve my sprints and how long I can flat out sprint?

Answer 1

I am a sprinter on my track team.  it really depends on your body build.  I'm a short guy but I have really strong legs.  The only problem is, the farthest I can keep a full out sprint is between 300-400 meters.  

Keep yourself hydrated before, during, and after you run.  It usually keeps me going.

Answer 2

You just don't have anymore energy. Like me, I run a lot and I get tired after about 2 miles but I push so I manage 3 sometimes then I sleep on the couch for half an hour.

Answer 3

I am a sprinter. I do mostly relays. This is common for alot of people. Try doing this:

sprint a half of a 100 (50 m) then walk another 50 m. then sprint, then jog. Do about 5-10  sets a day and this will improve your endurance, then start doing more sprinting. Sprinting 100's and what not.

Answer 4

You can improve your sprints by keep working at it to get faster you also might eat an to eat a cliff or power bar before you run.