What is The Fastest way to train and attain Good stamina as well as speed for running 400 mtrs?

Answer 1

run

Answer 2

shuttle run or beep test... like suicides.. since there is less time between beeps the longer you run it helps with your endurance as well as speed which is what you need for the 400

Answer 3

Try these

Speed Endurance, similar to speed or sprint training
Repetitions should last from 30 seconds up to 2-3 minutes as opposed to 5-10 seconds for speed drills.
Rest intervals between repetitions is reduced to prevent complete recovery.
keep sessions to 20-30 minutes maximum. Rest intervals should consist of active recovery exercises such as walking or jogging slowly on the spot.

High Intensity Shuttle Run
Pace out 30 meters on grass or a running track. Place a cone at the start and at 5 meter intervals (7 cones in total).
Sprint from the starting cone to 5 meter cone and back. Turn and sprint to 10 meter cone and back to start. Sprint to 15meter cone and back to start and so on until you sprint the full 30 meters and back.
Rest for 90 seconds and repeat. Complete a total of 6 sets keeping rest periods to 90 seconds.

Pyramids
Pace out 50 meters placing a cone at the start and then at 10 meter intervals (6 cones in total).
Starting at the first cone sprint all out for 10 meters and walk the remaining 40 meters.
Turn and sprint 20 meters and walk for 30 meters.
Turn and sprint 30 meters and walk for 20 meters.
Turn and sprint 40 meters and walk for 10 meters. Finally...
Turn and sprint 50 meters and then turn and sprint 50 meters again back to the start.
This is classed as one set. Rest for 90 seconds and repeat for a total of 4 sets. Rest for a full 3 minutes and repeat.

Cruise And Sprint
Mark out a distance of 100 meters. From the start gradually accelerate to reach full speed at about 60 meters. Sprint all out for the final 40 meters.
Slow down gradually, turn and repeat.
Continue for 2 minutes and then rest for 2 minutes. This is one set. Repeat for a total of 6 sets.

Hollow sprint
Set 5 cones out in 30 meters intervals. Sprint 30 meters, jog 30 meters, sprint 30 meters and jog 30 meters to the final cone.
Turn around and repeat always alternating jogging and sprinting. Work for 2 minutes and then rest for 2 minutes.
This is one set. Try to complete a total of 6 sets.

Cross Drill
Using 4 cones mark a box 30 meters by 30 meters. Place another cone in the center of the box.
Starting at the center cone sprint to each corner and back in a clockwise direction. Once you have completed a circuit rest for 60 seconds.
Perform a total of 6 circuits to complete one set. A session could contain up to 4 sets with a 3 minute rest interval between sets.