Splitting up runs in one day?

You can absolutely break your 8 miler up and receive similar benefits of doing one 8 miler , of course you now have to find time to shower and change clothes and extra time .
enjoy both your runs .

You can split it and get some benefit, as stone cold says. But if it's your ONLY 8-miler of the week -- in other words, if it's supposed to be your one long run of the week, then it's best not to split it.

The point of doing longer runs is to put sustained pressure on your heart, lungs and circulation. That way you get more endurance/aerobic development. It kind of depends what you are trying to achieve. Er... what ARE you trying to achieve? :)

I have to also add the mental aspect of doing a long run all at once is important.

Good thinking. It gives you a lot of confidence when it comes to a race, doesn't it?

Yeah, I think splitting your runs probably is about the same in terms of fitness, but not as effective in building endurance. In some ways, it might even be harder.

I'm wondering if you can "simulate" a long run by running hard, and then running long. In other words, if you have an 18-mile run to do, can you run 5 fast (10k pace) followed by 5 at your 18-mile pace? My theory is if you run hard, you can simulate the state of fatigue from running long, and pushing onwards would build endurance. In fact, would this make sense as a speedwork/endurance run in one?

bpalmer is new to this running game , guys , so I think the most important thing is to get out there on a regular basis for the first year then you can get into the long runs and the tempo's and the vo2 max work etc . bpalmer is going to become a better runner in the first yr regardless as long as there is consistancy in the program . Bones tendon and ligaments all become stronger as does the whole aerobic system during that 1st yr regardless of how long that long run is .
Patience and consistancy is the key to success in this game .

Agreed. In terms of overall long-term aerobic development it's time on the legs that matters. That's how you build structural strength as you say stone cold, and also what brings on the superior cardiovascular stuff such as new networks of capillaries forced into working muscles, enhanced energy production and so on.

So baldwyn, I don't think you can simulate the long run. I sort of experimented this year along those lines. I was playing "catch-up" all year due to the anaemia thing, and when I started running out of time with my goal race looming, mistakenly abandoned my longer runs and tried to get fit quick with racing and speed work. What I forgot was that, when you do that, you are working totally different energy systems.

That's what'll happen if you do 5 at 10k pace and 5 at 18 mile pace; the fatigue you will deal with will not be the same type of fatigue as you deal with in the course of an 18-miler (which is predominantly muscular fatigue, I would think.

We need to spend the time out there just doing it, I feel. We can make the long runs easier by interspersing a walk section, or walk breaks, but I think trying to have it take up less time is not a good idea.

Thank you for your help. I am completing abiding by the rule of running my long runs (on the weekends) in one run (not breaking it up, because that defeats the purpose). I was just curious about these longer runs during the week, but I understand what I need to do now. Thank you. January's race will be my first marathon; I just want to finish; not concerned with my time. That will come with more marathons in the future. Thank you for your help. And thank you Stone Cold for remembering that I am new to running:)