Training For A Marathon | How Many 20+ Mile Long Runs Should You Do?

When training for a marathon - how many 20+ mile long runs should you do? We decided to ask runners this question while walking around the San Francisco Marathon expo. As you can imagine there are a lot of different answers here and no shortage of opinions.

In the second part of the video, Coach Nate reviews the purpose and benefits of these long runs, the drawbacks to doing too many of them, and how best to determine the right distance and number for yourself. Let's jump in...

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[IanLoughead]

I train my athletes by time. Longest run is 2 hours 45 minutes. Aiming for a specific distance means some athletes could be on feet for over 4 hours in training. The recovery from that is huge. The focus should be the whole week, not one run.

[stolts]

I'm one of the slow runners (first marathon was 6:50:00), so I cap at 3 hours for the long run. Strength and intervals are the focus.

[thedanishking]

I am running my first marathon in a month, have done an 18, 19 and 20 mile run so far - the final 22-mile run is coming up this week. Feels good so far, all of them has been under 3 hours.

[lfmars]

I don't think it matters much whether it's 16 or 20+! It's about weekly volume that makes you stronger for a marathon!

[pantingdog]

Ran a 3:15 marathon on only 35 to 40 miles a week. That included several 16 miles, and just one 20 miler.

[billprocter]

Balance is more important than a long run. I will spend 20 min before and after my run softening tissue (foam rolling, ) mobility, and/or strength training. Total weekly mileage is more crucial to me than one big long run. Not saying I don’t ever get a 20 miler in but I feel ready to go with a handful of 16 milers during a marathon training cycle.

[mauriciosalazar]

Ran The Sfo Marathon last July. It was my first marathon . Had a 3 hrs 51 mins. While I was training for the marathon, i just did one 20 mile training and it was three weeks before the marathon. Love your videos, regards from El Salvador

[IRunThings]

i did a lot of long runs for Philadelphia. I basically kept adding two miles to each long run, I did one 20 miler, one 22 miler, and one 24 miler.

[iberiksoderblom]

If I've had a long break from running, like I recently have had and only done up to 10 km's (6.2 miles to you US Americans that still uses mesurementsystems from the Middleages 😂), I take two half-marathon races a week apart, then a 32 km training run at slow speed and then finally a half-marathon race one week before the marathon.
If I'm strugling with my strengh, I put in a 28 km run between the first and second half-marathon race.
So either I do four weeks of end-preparation or five weeks.
But building the base before the end-preparation periode takes a lot longer...

For the ultra runs, I from time to time do 4 - 6 hour runs at really low intensity. Its about keeping rytm with drinking and eating from the vest and working steadily when in the "pain cave".
And also I have found that if I do not do this regularly, my feet seems to loose strengh really fast.

Oh, and I just love to run...

[ChadHiggins]

I've been running actively for 1.5 years and each month I up my average mileage just a little. This has been a natural progression as I feel more fit and capable. I try to do one weekly long run (doesn't always happen, but I plan on it nonetheless). I'm not training for a marathon, but do plan do run one "soon", and really I'm just training to continue to improve my capacity and abilities. My long runs are now 15-18 miles long at a 7:30-8:00 min/mile pace. For context, I now average 45-50 miles per week. I've stayed injury free and hope to keep it that way while slowly increasing my base. During the week, I'll do a mix of tempo, recovery, and possibly an interval run. Just this last week, I ran a 10 mile PR at 6:55 min/mile avg and an 18.3 mile long run at 7:40 min/mile pace (2 hrs 20 min run).

[JonsConsciousLife]

For my first marathon I only ran one 20-miler at 3 weeks from race day. For my second marathon, I did one at -5 weeks and -3 weeks. The second one included an 11km Warmup then a HM at goal pace/strategy. My third marathon was only 10 weeks later, so I eased off for a couple weeks to recover and then did a 20-miler at 6 weeks out and again at 3 weeks to race day. In both marathon 2 and 3, the first 20mi run was on a Sunday, after a 10mi steady run on Saturday, designed to get me used to running when tired. Nothing too taxing, just enough to get into the race day headspace so you can feel confident in the last 10k.

[kyoshimadoshi]

Thanks to the Asian guy for km's.

[Heyman]

Longest I did was 16 miles before my marathon. I was supposed to do my first 19 mile run last week but ran through to 26.2! Probably could been faster with more training but I felt good and wanted to do it!

[safiad]

I ran my first marathon a few months ago and my longest run was 30k (18.75 miles) which I ran in about 2hrs 30mns. I don't think you necessarily need to run 20+ miles, but I guess it depends on how fast you are. What really worked well for me was to include intervals at around 10k pace during my long runs to get my legs really tired before I practiced my marathon pace. And I actually ran my marathon way faster than the "marathon pace" I trained at during my prep ( I was aiming for 3'45 but ended up running it in 3hrs 23mins - and I'm a woman).

[bpetersson]

The answer depends on what your ability and expectations are. In my experience, the most important decision I made was to get a coach and talk through what I was trying to accomplish. The goal for the first full marathon was to finish a half first, and then take 6 months to get to a full marathon. Also, if your goal is somewhere around 3:30, that is very different from doing a 4hr PB. Also, if you are starting from scratch, more or less, give yourself a year to avoid injury. I knew people that got all exited about their progress and started running too fast and too long and they never recovered from the initial injuries like IT bands etc. Having said all that, for the first full, doing up to 16-18 miles and then taper for 3 weeks is reasonable. For the next 2-3 races I did 5x20 miles in consecutive long runs with tempo training twice during the week and at the end when we tapered, running the 14 miler felt short! The recovery part was also really important and if you felt tired, you just took days off until you felt healthy. This is for a 3:15-3:25 PB. If you want to it sub 3hrs, you need a lot of speed and strength work, but remember that the real race starts at mile 20, and if you havent built up the energy reserve through your training, there is nothing you can do.
One last note is that modern marathon training programs started with Emile Zatopek, (Olympic gold in the 50s) who used to run 26x1 mile intervals in one block. Meaning, it was ALL tempo runs. But if you are just doing a leisurely 4hr time, just run with your club or group runners and stay healthy and enjoy it. You will improve over time with the help of your coach.

[TayLybb]

I did 2*20's and 1 * 18 and multiple at 15, 16 this last marathon prep. It helped greatly to go through wall before the race

[colino]

100% agree with the holistic comment. For me, I do a coached quality exercises day (track, hills, intervals), slow recovery day, tempo day (my LEAST favourite) and long run day. Non running is 2 gym session - one is mostly is movement/mobility (usually the day after my long run) and the other is strength focused, which has been critical for me in no longer having chronic knee problems. Done a fair few half marathons and shorter, now going for first marathon, and so far built up to 30km, will max out at about 34, then taper back. Every week is a new distance PB at the moment!

[jonathansandberg]

Interesting. I love long runs and I hate track/speedwork. I’ve been running marathon + distances every Saturday since June and I’m definitely getting faster. Maybe I’d improve more if I did intervals and tempo runs but I think there’s an argument to be made for just doing what you love.

[ngwan]

I have done about 8 Marathons in total and I hit the wall in 6 of them. Even during training I can fell my body coming close to bunking after about 17 miles of running.
For these reasons, I decided I will do at least three long runs over 20 Miles to get my body used to that last 10K.

[kostasastro]

Last year i tried a new 21 week program for a marathon, the long runs stared from 20k and they were every second week reaching to 37km. During the week i had my tempos, intervals, aerobic and easy runs, also i had some core strength exercises. Since the long runs were every second week i could recover better than my older programs where the long run was every week and i couldn't wait for the next long run, each time i did a PR and finally i run my marathon with 30min record.