If u r starting from scratch.. start with slow pace but long
distance. something like 3-4km will do. Slowly build stamina. Speed
up as u progress.
Once u reach a comfortable confident level, den u try to really run
ur 2.4.
N yes.. regular training is required. 3 times a wk would do. Give
urself at least 2-3 mths to see significant results.
Jiayou wor. 
