Benefits of speedwork during Marathon-training

Question

After several half marathons and trailruns of around the 25km, I started training for my first marathon on the 15th of Octobre this year. Currently I'm running about 4 times a week with the longest run about 24km (15 miles) without getting into trouble. Running a total of 55km (34 miles) a week. Steadily (without exaggerating) i'm building up my training volume.

A friend of mine (who already ran several marathons so far) advised me to incoperate some speedwork into my training. However i don't want to race within a specific time, I just want to finish without suffering too much.

So my question is, what are the benefits of speedwork during marathon-training? Keeping in my mind that I won't race to arrive within a specific time. Wouldn't it be better just to keep increasing my milage at a steady pace?

Note: I did ready up on some internet-pages. But they all seem to refer to a better finishing time.

Answer 1

What speed work can do is make the slower paces easier to maintain at a great distance. So let's say your current LSD pace is 12 min/mi. You can currently run a half marathon at 11 min/mi. If you did speed work and got your half marathon pace up to 10 min/mi. The 12 min/mi pace would be much more comfortable. As such, you would be able to run a 12 min/mi pace longer than you could previously.

For the first marathon, I would say the thing to focus on right now is distance. You want to make sure you can make those numbers first before you make sure you can make those numbers fast. There is no need to make changes to a program as long as it works. You'll definitely want to incorporate speed training eventually, but don't start just yet.

Answer 2

From what I've read from coaches like Jack Daniels, the main purpose of incorporating speed work (whether it's intervals on the track or tempo runs) is to increase your lactate threshold and your running economy (how efficiently your body uses oxygen). While being able to comfortably run faster is a huge benefit, it can also help in longer runs since your legs won't build up lactic acid as quickly

That being said, if you're just looking to complete a marathon, hitting your weekly mileage is definitely more important - not only will it prepare you physically but mentally as well.

Best of luck in your training!