Training Advice

I believed that running on tired legs with long runs and back to back runs were the bread and butter of ultra training, keeping within what your body can cope with and not breaking down.
Recently I have been advised to  train on fresh legs and to maximize my  long runs at 4 hours. I have the utmost respect for this athlete but am a bit anxious that I will be undertrained and unable to complete my event.

Any comments would be appreciated

Depends on how long the ultra is and how fast the runner is. A fast runner-3h or less for a marathon-can get away with that for short ultras, say up to 35 miles but would still benefit from longer sessions. If you are slower or are doing longer ultras then there really is no replacement for time on your feet and the more of it the better.

You do get some runners say they never do long training runs but then it turns out they are doing events several times a year over long distances and for times upwards of 5 or more hours. Those are their long runs they just don't count them!

If the person giving the advice is an ultra runner themselves, and they know you and your abilities and the event you're training for, they might be right. But if you're planning on doing a 24 hour race, four hour training runs won't be much use to you.

Oops dont know why email didnt tell me I had answers 

Its a 24 hour event at the end of February. Coming back from injury last year my marathon time now is about 4.10. PB before injury was 3:55 I think. I do one minute walk every mile roughly for most of my long runs now except if my long run coincides with a marathon event and I do it as a lsr continuously with no walks.The next day I am able to do a 20 miler with run /walk in about the same time or faster than the first 20 of the previous days marathon.

I have possibility of a 12 hour event next month which I could use as a trial run for the 24 and as I am not competitive , I think I would be able to hold back and not go eyeballs out and mess up whatever I could manage on the 24.

Does this make sense?