At what point would you begin to start doing double days?

As many have mentioned, start them now. You will be able to build your mileage a lot easier over time with doubles. Last year I would do 60 mpw in singles and was exhausted. Then I tried building to 70 doing 8/3 doubles - still tired. Now I double 6/4 on easy days and 9/7 on workout days. I feel so much more fresh for each workout. I am able to get in a lot more quality and volume each week. May not work for everyone, but it seems to be working for me.

After re-reading I can see how that is confusing.

Running 65mpw in singles, I experimented with doubling but keeping total mpw at 65(~50 in singles+15mpw in "doubles"). I think just reduced how hard I was working overall. *I'm also regretting bringing up weight on a message board as it's really inconsequential and could give the wrong idea

I found that for me 65mpw in singles was kind of optimal/minimum and then I added doubles on top of that eventually building to 80/90mpw consistently into Jr. /Sr. year

The second my injury/niggle adeptability go away.

I have tried nutrition, sleep, easier runs, more days off, more/less miles, rest, form, shoes, insoles, bloodwork, etc.

I'm on the literal last thing i can think of, and that's total body strength.

If this doesn't work i will use peds or quit.

Outside of a long run no reason to be running for more than 60-70 minutes. Once you have maxed that out I would start doubles

There's lots of talk here about how 60+ min runs are more detrimental than they're worth as a recovery day. I jumped from 60ish to 80 this summer on 6 days, and the biggest difference maker for those longer singles is food. If you can eat maybe 100 cal of carbs (I like chews, gels are expensive) during the run, it feels so much better and the long days are easy to recover from.

On something like an 11/4 double, I'll eat ~150 cal of basically gummy candy during the first run, then another chew or two before the second one.

But if all you're doing is the 10-12m easy run, it is so much more beneficial as an easy run if you eat tons during it, reducing the need to double. Not that doubling is bad, it just is possible and productive to run 70+ in singles more than the other posts suggest, if you're smart.

senior in high school at the latest.

A friend of mine ran a 2:12 marathon off of only singles. He argued that you get a 24 hour recovery and your body gets more used to the pounding needed for the marathon. Two 10k runs are not as good of a stressor to your endurance as one 20k run.

Some good posts in here. There's definitely not an exact science to it. Time constraints probably is what puts a lot off doubles. The literal ability to actually change into gear etc twice a day.

Along with half the world, I'm a massive fan of what sirpoc has done in the "Norwegian lower mileage" thread. I think on singles, he has absolutely scraped every ounce of juice he can. Where he is at (7.5 hours a week), I think that's the top end of singles most likely. Much more than that, doubles would be preferable. For him, doubles night come into their own on workout days. At 40+ years old I find it hard to believe doubles on easy days would/will make him any faster. But I might be wrong.

I would say though his approach and that thread tells us probably you can succeed. Just as much on singles, around or up to that 7 hour mark. But beyond that, of course running an hour or more straight everyday aside from your weekly long, sounds like a recipe for breaking down.

At hobby jogger level, I would imagine most of the guys running 8+ hours or more, the majority are naturally spreading the stress with doubles anyway?

I believe this is true. I have trained identical mileage in both singles and doubles for prolonged periods and compared my fitness gains using both Runalyse VO2 max estimates and race times (which correlate very well for me). When I am doing 80-85 mpw in singles my fitness increases at a much faster rate than when I am doing the same mileage in doubles.

Having said that, I have never gone longer than 12 weeks running singles with that mileage without an injury that has massively interrupted my training. I'm currently at week 22 of running doubles (now at 95 mpw) uninjured, and my fitness is much better than I ever managed between injuries while running singles. So for me, the consistency is much more important than the faster improvement I got with singles. Your results may be entirely different. Everyone needs to figure out what works best for them.

Any easy run that takes longer than 75 minutes I would break up into two runs

Typically what I've done has been:

Mondays - 9miles am / 4-5miles pm

Tuesday- WO (10-12miles)

Wednesday - 10-12miles Single run

Thursday - 9 miles am / 4/5miles pm

Friday - WO (10-12miles)

Saturday - Easy LR (2hr at the high end)

Sunday - Rest or 6-8 miles

OK, but you appear to be missing why malmo stresses doubles.

You aren't doing them because of running time length or because your weekly mileage is getting to an upper range.

The point of doubles is to introduce "two stresses on the body each day".

malmo explains this is post #11 below:

https://www.letsrun.com/forum/flat_read.php?thread=5841254

I have the get sleep convo every day--legal PED, need to recover, you get faster while you sleep...doesnt seem to stick.

My kids are 15-35 MPW, average is around 25 for girls and 35 for boys. Im considering something new. No doubles, but what about "clustering" two threshold sessions back to back on two consecutive days? Normally we run recovery/ easy run after workout days but im looking at maybe moving speed to monday, then a short rep threshold on wednesday (say 15 x 400) then long rep threshold wednesday (say 5 x 1000 or 1200? or use minutes)

Then we have that recovery on friday, meet saturday? Yay nay?

If I want to add mileage but for some reason simply can't make my individual midweek runs any longer, then I'd add doubles.

well said

add

note what works

i personally hated the very early morning run, but they seemed to pay big dividends.

later morning shorter runs at a healthy pace with hills, was a favorite. not taxing but a bit of quality.

try to meter it and see what actually is effective.

or the most fun. which is brain food fot motivation.

My understanding was running around 60 minutes was good aerobic training. Between 60-90 was kind of that grey area where the benefits started to drop for a regular run, and wasn’t long enough for the benefit of a long run… something I consider minimum of 90 minutes

I started doubling when I got to about 45 mpw. For me it was both a schedule and a desire to stay injury free thing.

Especially in the Spring and Summer it is light out by 5:45 am where I live. I could run 5-6 miles and be home and showered by the time my son woke up and then I could feed and play with him for an hour before work. He was usually in bed by 7:30 pm so that gave me another 45 to 60 minutes of daylight to run another 3-6 miles. I don’t double every day but by the time I got up to 60 mpw I did double 3+ days a week and I would take one long run on a Saturday or Sunday instead of doubling.

Personally I feel much better and less sore after runing 6-8 miles in the morning and 6 miles in the evening than running 12-14 miles consecutively. For me my knees tend to flare up after more than 9 or 10 miles consecutively.

When you have nothing else going on in your life

With the possible exception of the high school athlete who really will otherwise sacrifice sleep, start them today. No reason to wait. No particular mileage threshold. Just add a three or four mile run in as many mornings as possible, start there. It doesn’t matter if you are doing 3 and 5 doubles or 3 and 10 doubles. Just start doing them. Eventually, and in the not too distant future, you might be running a 4/8 or 5/10 double every single day. There is no quicker or safer way to increase mileage and improve.

Read the guy’s post on here who couldn’t find any other way to absorb the training or the guy who got up to 90 mpw in short order. Doubling is the magic elixir.