Long slow runs why?

Your body needs to adapt physiologically to get you through a marathon - and the theory is those changes to improve endurance only happen at low intensities.  How you measure "low" is debateable, but, as a guide

1. You can still breathe through the nose (only), or

2. Heart rate less than 75% max, or

3. 10% to 15% slower than achievable mara pace (which you don't know yet,  but as a guide, for men, 2.29 x half mara time).

I checked with some sub 3 Fetch buddies and, up to the last few weeks, their average training pace is around 8mm (which means the long runs are slower than that, as the tempo and MP runs pull the average down).

These forums are littered with (male) runners who train too fast and blow up at mile 18...feeling fine after 13 miles doesn't mean you'll be fine 10 miles later.

As above - or, in short, because it allows you to build up stamina. No point having speed in a marathon without having the stamina to go with it, you'll get to about 17 miles  (if you're lucky) and stop dead.

What are your race times so far? Without that your training pace figures lack context but it sounds to me like you are training too fast.

I found the Pfitzinger & Douglas book "Adanced marathoning" very useful at explaining the various sessions that most training schedules are built upon.

A quick quote from the long run description:

"balance between running hard enough to simulate the muscle patterns and posture you will use at marathon race pace and running moderately enough that you can recover relatively quickly for your other important training sessions."

Pfitzinger, Pete; Scott Douglas (2008-12-26). Advanced Marathoning (Kindle Locations 2727-2729). Human Kinetics - A. Kindle Edition.

If you are saying that you are not feeling any ill-effects from running 13 miles at 7:09 pace, then don't worry about it..  If you are feeling stiff-legged or just a bit tired the next morning, slow down.  As your mileage increases during your marathon training, you may find the accumulating tiredness gets to you and if you don't realise this you are guaranteed an injury.

I've seen plenty of people running long distances at good speeds in training, but it doesnt seem to translate into the times you'd expect on race day.

I think a lot of people just tire themselves out in training and on race day, they're just too knackered. 

If you do your long runs - so 20miles plus at basically your race pace - then how can you recover from that in a couple of days to do more training ?

The plans arent just theoretical  - they do work if you stick to them and use some common sense. 

Speed work is also essential - but you cant do both at the same time. 

I find the long slow Sunday runs invaluable - not only do they increase my stamina, they burn more calories than a shorter, faster run and they give me time and practice at dealing with the psychological side of running.  My brain wants to give up way before my body does and allowing myself to run a longer distance at a slower pace means I can train myself to overcome the 'I just need to walk' voice that usually pops in my head at around 8 or 9 miles - I run without music as I generally run by myself and it's safer to hear what's going on around me.  Also, I practice gel and fluid intakes on these longer runs as you can't tell how your body will react to eating/drinking on a 5 mile run - and you don't (or shouldn't) need it on such a short one anyway.

On a purely selfish level - the LSR also gives me time to myself to think stuff over and just enjoy running. 

Lee - I'm newish to running and l started off running as fast and as long as I could. I was tired all the time and my legs were constantly aching. I then started following a half marathon training plan and my slow runs were at 10:00-10:30 mins. Even though I was training for a half I did LSR up to 20 miles. As I had slowed these runs down I wasnt burning myself out and felt good for the race. I only did a small amount of speed training as well. I set myself a target of 2:00 and finished in 1:47. Therefore, I am a firm believer that training plans, and LSR runs, definitely work

50 miles a week sounds a lot for a fairly new runner. 

The tempo and speedwork sessions are where you work on speed.

The LSRs are where you work on stamina.  If you do these too fast you won't be recovered enough in order to do your hard speedwork sessions properly.

Lee, are you doing any 'hard' sessions, as in Interval sessions, or tempo/lactate threshold runs. These can take it out of you, and to do them successfully,  taking things easier on your other runs is often the way to go.

Different paces or heart rate zones are used to train different aspects of your physiology. As Teknik pointed  out there is a lot going on 'under the bonnet'. I'm no mechanic, but did as I was told churning out easy miles on the long runs, and putting more effort in on one or two speedier sessions per week. This year  as a novice runner I scraped a 1:22 half and 2:59 marathon.

Even if you don't follow their plans, I found Pfitzinger & Douglas book "Advanced marathoning" really useful in explaining the purpose behind each type of run.

As has been said, accumulated tiredness can catch up - I didn't recognise this as a novice, and ended up injured and running the marathon not 100% fit.

When training for my half, I was also running my long runs at my half marathon pace, I didnt' know to run them slower. Now I'm also going to start training for the Edinburgh Marathon (my first one too!)

Was recently told by a running coach that the long slow runs teach your body to use fat stores for fuel during the marathon, leaving the carbohydrates for when you need them - the 2nd half of the race (6.2 miles ) Your body will become more efficient by training this way, so that when you come to do the marathon, it will know to use the fat first. She also said what has been mentioned above - when you get to the part of your training plan that has your long runs at half mara or greater, you will only end up tiring yourself for the training the following week, requiring more recovery time.

Good luck with your training, and see you in May!

the long slow runs are invaluable for stamina. Make sure you do them or you may find out the hard way why a lot of runners say the real halfway point of a marathon is 20 miles

good luck with the training

Hi Lee. I asked the same question at the Asics bootcamp a couple of weeks ago. I've always tried to run my long runs at almost marathon pace, but then obviously struggle the few days after with my runs with tiredness.

Doing this means your body doesnt get the chance to recover and is continually fatigued (these aren't my words, but what I have remembered the expert saying )

I find it really hard to do this though, but after trying it the past 2 weekends, I've found my Garmin has really helped to keep me at a slower pace. So I'd recommend keeping it on.

As others have stated, it is all about increasing endurance, without tiring yourself so much that your other runs suffer. It is also about increasing running efficiency. You can not increase your Max Heart rate, but can lower your Min Heart rate, this gives you a larger training range. i.e. If running slow takes less effort, running quicker will also take less effort.

I am also a big fan of P&D Advanced Marathoning. Even if you don't follow the 18 week schedules they explain the reason and effects of each run.

http://www.mcmillanrunning.com/articlePages/article/2

I also read the above article prior to each campaign, to remind myself of the 2 types of long run.