taking readings after 2 hours?

[neededthat]

im reading alot of ppl are taking readings after 2 hours and that if you had took the correct amount you should be back to pre food bg levels but i was told insulin is active in your body for up to 4 hours is this wrong in what i was told? im on novarapid.so am i not right in thinking it could be up to 4 hours before being back to the level you was? little bit confused

 

[totsy]

hya,
it can be 4 hours till back to before levels, i check every so often after 2 hrs as this is when the spike is highest