Trail Running vs Street Running Mile Splits?

[mrothwell]

I'm training for a 10 mile race coming up at the end of April, and its going pretty well. I've mapped out a bunch of routes and timed them with my watch, I'm cruising at a ~715-745 pace. About 2 months ago, I decided to add trail running to my workouts to keep boredom away and add a bit of cushion under my step. I just did those runs by time, ie, an hour run is ~8 miles, etc.

Well things were going great until I bought this GPS watch, a garmin 410. My street pace is spot on with what i've mapped out, but I've found that my 1h:30 trail run is less than 10 miles! That puts my trail run pace around 9:20.

The question is, how should I put these runs into my schedule? An hour run on the trail makes me about as tired as an hour run on the road, its just less miles.

[Papa Dras]

Huh? Put them in when you want to break up the monotony of street running. What does the time matter?

[mrothwell]

Huh? Put them in when you want to break up the monotony of street running. What does the time matter?

The time matters because thats the only constant i can draw between the two. 8 miles off-road is much harder than 8 miles on the road, and takes me much longer. So if my HR is elevated for the same amount of time, but I go a shorter distance, am I getting the same benefit?

[SivNiz]

are you taking into account elevation change? I would imagine the trail running have more grade.

[lojasmo]

The time matters because thats the only constant i can draw between the two. 8 miles off-road is much harder than 8 miles on the road, and takes me much longer. So if my HR is elevated for the same amount of time, but I go a shorter distance, am I getting the same benefit?

Same cardiovascular benefit, but not the same endurance training (body stress from number of steps, heel strikes, etc)

I only run trails.

[mrothwell]

Same cardiovascular benefit, but not the same endurance training (body stress from number of steps, heel strikes, etc)

I only run trails.

Hmm, gotcha. Might keep the runs on the road then while training for road racing. I'm jealous that you have the trail networks available that you can only run trails.

[lojasmo]

Hmm, gotcha. Might keep the runs on the road then while training for road racing. I'm jealous that you have the trail networks available that you can only run trails.

It's a local 5mile MTB loop. I run a little less than half of it in roughly 40 minutes.