Actually its really good practice to include bike workouts in your running program. Bas Van Hooren (28:30 10k runner) even uses this in his own training as he discussed in this podcast. Its an exceptional modality for promoting recover and cardiovascular endurance without the neuromuscular/musculoskeletal strain associated with running. In fact we have this for most Athletica running programs and people question it all the time. Not traditional but supported empirically and by the science.

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https://athletica.ai/
https://hiitscience.com/

Not at all. I ride 8-10 hours weekly to supplement my running. Pretty much all easy.

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Let food be thy medicine...

It’s excellent cross training.

As a triathlete.......................Of course I have.

When I trained for a stand alone marathon, I included one ride a week of about 3 to 31/2 hours to get my endurance box checked. I did a very low mileage running program, but with all high intensity marathon paced runs, and this ride helped shake my legs out and get that over distance(in hours) training in. I believed it worked well for me, and it was a small step to get back into Tri training once this 2 month bloc was done with...

Most stand alone runners have far more time to run than would be advisable. Which is to say, there is probably plenty of time to do some riding, and as others have mentioned, it might be a good thing. It sort of spits in the face of specificity, but even that guideline is not an absolute.

Personally, I have had my best open marathon results when I put tri to the side and focused 100% on running. That said, I agree that adding in some easy aerobic cycling can't hurt you so long as it does not impact your ability to nail your key marathon sessions and hit your total weekly mileage goals.

That said, some folks are able to carry cycling-specific fitness over to running really well, allowing them to do a lot of intensity on the bike and keep their run mileage low. I love this idea in theory, but it has never worked for me in practice.

I was a competitive runner for 30+ years before crossing over to triathlon. I focused on the Marathon distance for 2-3 years as a young man in my late 20's, crossed over to Triathlon in my 30's, then did my first marathon in a dozen years in my 40's.

In my 20's I ran every day (45-55 mpw), did speed work with the track club every Tuesday, did long runs with my training group every Saturday, and my best result was a 3hr 14min.

In my 40's I ran three days (20-30 mpw), cycled three days a week (75-95 mpw), and swam twice a week (3500-4000 ypw). my best result was a 2hr 54min.

I have found that triathlon training is more effect run training for me at every distance I have raced from a 5k to a full marathon. My running plans now look like a run focused triathlon plan. If I want to PR on the run I might allow myself to miss or shorten a few run workouts, but I don't miss my swim or bike workouts because the more consistent I am with them the better I do in my running events.

Some of the benefits I see for running are 1) cycling increased my run cadence, 2) Cycling increases the volume I can train at each week, 3) cycling allows me to hit my target marathon HR for the entire duration of a marathon without having to run a marathon at race pace in training (and I can do it every weeks without needed a lot of recovery time).

I have only done this since the beginning of June, but I bike 60-90min on the trainer around lunch time and then run 10miles easy mon-wed-fri and LT1-LT2 depending on weather/motivation on tue-thur-sat. Sunday is off/super easy swim and it has been working really well. I tried to implement some LT2 on the bike a few weeks back, but the run suffered in the afternoon. Could be because we had 110 degrees so I might try it again now that the heat wave moved on, but as long as I keep the bike rides at 200-210w my legs are really good in the evening.

I'm training for a marathon in six weeks after a season of triathlon and came across your post. What were you doing in your three runs in preparation for your marathon? Did you still do a long run and marathon pace work? Or did you split the 30 mpw equally? I'm at about the same mileage as you, but I am running four times a week at the moment.

I like the idea of doing the intensity on the bike because I also recover way better from cycling than I do from running.

All running programs are based on three key runs 1) Speed Works 2) Tempo Work 3) Long Runs.

I would go to the Track on Mondays and do 1-2 mile worm up 3-4 miles of intervals followed by 1-mile cool down for my speed work.

For interval work I would start with something like 2-miles easy, 3-miles tempo, 2-miles easy and increase the tempo time and decrease the easy miles until I was doing about 8-mile at tempo pace.

For long runs I would start with 12 miles runs and build up to about 20-22 mile runs. I also would do some race pace stuff in the last half of these long runs by either doing one mile at race pace then one mile easy for the last 6-8 miles or by dropping 5 seconds a mile off my pace every mile for the last half so that I would end just under race pace, etc.

Search for the Furman Institute "Run Less Run Faster" Plan. It will give you the 3 run work outs that you need each week and you can do cycling/swimming on the other days.

Yeah, I guess I just wondered if you had replaced one of the quality runs with a "similar" workout on the bike. I'm doing my "speedwork" on the bike instead of at a running track and was curious to know if anyone had tried something similar. Each week I'm doing a long run and a marathon pace run, and then two easy runs. Then I'm doing two workouts on the bike where I'm riding either just below or just above FTP. So I'm not doing any running faster than marathon pace (since that tends to be when I get injured) and hoping that the intensity on the bike will be a good substitute.

It sounds like you basically did the FIRST marathon plan key runs and then used cycling for "easy volume", which is different.

Given that speed work has a significant neuromuscular specificity component to it....I don't know how that's supposed to work? Speed work is about teaching you to run-fast, and build RUNNING specific economy. That can't be done very well on the bike.

The alternative of using cycling for general volume (either-or) has been well-demonstrated.

Yeah, that's why I put "speedwork" in inverted commas, I realise that an FTP workout on the bike is not actual running speedwork. What I mean is I am doing intensity on the bike, rather than on the run, with the goal of maintaining LT so that when I do run hard I have the physiological capacity to run hard. For neuromuscular training, I do strides on grass at the end of a couple of my runs each week.

I know a number of good marathoners who cycle to supplement their running. All of them follow Curtis' approach of building extra general aerobic fitness via easy bike. And reserve the intensity and specificity for the running. I don't know anyone that does it like you are proposing. I don't think fast/threshold running is much like threshold biking.

I guess I'll be the guinea pig then!

This approach worked well on my triathlons this season - I managed to run 1:26 off the bike in my half-ironman ten days ago, which was a PB for me. Also, I do think fast running and fast cycling share some important similarities, not least of which is the mental aspect of pushing on and holding pace through discomfort. And the most specific run workout for marathon racing is the marathon pace workout, surely?

If you are going to be the guinea pig, then you have to do it twice. Once each way....and report back which worked better. :-)

Maybe its just me. But, I like running fast. So, I would never purposely eliminate it from my run-race-prep---Its such a small amount of the plan, anyway.

I have done a couple of different approaches to marathon races on triathlon training.

1) I have followed a 70.3 Triathlon plan with no changes other than increasing the volume of the long runs by 20%
> There are dozens of 70.3 plans but this generally means that you are doing 3-4 hour bike rides every weekend which are probably going to be pretty close to your target HR for your marathon race pace (depending on which 70.3 plan you have).
> Long runs are probably going to be capped at about 13-15 miles depending on you 70.3 plan. Adding 20% gets you up to 15-18 miles for your long runs. Will all the bike volume of a 70.3 plan and intensity of the shorter runs you will crush the marathon, especially if you have done some recent 70.3 races and are used to events that are much longer and hotter than a marathon.

Note: When I did this my run volume averaged 24 miles a weeks with my lowest volume week at 14 miles and my highest week a 35 miles. I was averaging around 10 hours of training though which is more training time than any of my training buddies who just run do for a marathon.

2) I have used the Run-Less-Run-Faster-Plan with 3 bike rides and 2 swims.
> With this approach I do the speed work, tempo work long run. Long runs are longer than the 70.3 plan.
> The weekly miles is going to average more like 30-35 miles a week with peak weeks over 40 miles.
> Since I am building the endurance for a marathon with the long runs (and I am not training for a 70.3 Triathlon) I keep the long bike rides to about 90 minutes. I might go as much as 120 minutes but that is it but no 3-4 hours rides. I also might do something like a 60 minute bike ride with 30 minutes running off the bike if I want to get in more run volume or I want to practice race pace running or want count my run cadence or work on anything else for the run (i.e. race equipment, race nutrition, etc.)
> I do the long ride outside on the weekend and the other two bike session are 60 minute interval training session on the bike trainer indoors. I typically do a threshold type workout that might be 5 x 8min @ FTP w/ 2min recovery or a VO2_Max type workout that would be something like multiple sets of 2-3 minute intervals. The longer intervals 8-30 minutes are only done on the out door rides so the indoor stuff in not just filler volume. I am improving on the bike at the same time that I am improving on the run. Running elongates your muscles and cycling compresses them so you can do them alternate days and things work.

So here are a lot of ideas. The important thing is to 1) build your endurance (long runs or long rides), 2) increase the length that you hold intensity near race pace (tempo runs, fast finishes in the 2nd half of your long runs, etc), 3) to improve your running efficiency by doing workouts that are faster than you marathon race pace (i.e. speed work at the track). If you skip the track workouts you will still finish the marathon. The Long Run is the most important thing if you just want to finish. If you are going for time you are going to want to do track workouts though.

Oh...and I like to run fast too. If I was doing a couch to Marathon plan in less that about 10 weeks I might skip the speed work and just focus on building the endurance due to the lack of time. If I had more than about 14 weeks though I would do the track works outs.

Thanks for the info and ideas, much appreciated.

IMO tempo runs (threshold pace or near hour race pace for ~20 min, or a bit slower for longer) are the most important marathon workout, and I think you’re doing yourself a disservice by not including them in your training plan. I would also not call either tempo runs or training close to FTP “speedwork” - I’d use that term for running paces or cycling paces considerably faster than threshold.

I’m going to agree with Tom here. I have run good marathons where there was some cycling or skating intensity in parts of the training block. But running a good marathon is mostly about putting in the run miles (and intensity) in training.

My best marathon (NYC 2019, low 2:40s) was on the heels of the first time I trained for triathlon over the summer; the 12 weeks prior to the race averaged high 50s mpw running and 2.5 hours a week of biking, skating, and other stuff, much of which was moderate to hard cycling, which tapered down to ~1 hour a week, not too intense, in the 5-6 weeks leading up to NYC. The following summer (2020, few races) i leaned harder into mixed training, and ran a solid solo marathon (low 2:50s) on low 40s mpw and ~6 hours a week of cycling, skating, and other stuff, with more sustained intensity in the non-running sports towards the end of the block. It’s hard to compare because it wasn’t an official race but nevertheless I think the lower run mileage and higher training stress in the other disciplines (leading to higher general fitness) did not ultimately help my run time.

I can also add in a “control” marathon training cycle from fall 2018, low 2:40s marathon time again (not quite as good as NYC) on high 60s average mpw running and ~1 bike ride a week of maybe an hour average duration, some 2-hour rides early in the training block. Less total training time and overall intensity, nearly as good a result as NYC 2019 (though on an easier course) and much faster than the solo 2020 effort.

So, overall, my takeaways from these 3 marathon blocks — 7 hr/wk run + 2.5 hr/wk other > 8 hr/wk run + 1 hr/wk bike >> 5 hr/wk run + 6 hr/wk other — are generally pretty orthodox:
-running more miles is the most efficient way to run faster
-adding easy cycling throughout is great, but don’t add so much that it really cuts into your run volume or intensity
-some intensity in cycling early in the training block is ok, but fade it out as the block progresses and the marathon workouts get harder
-IMO a huge value of adding some biking can be to alleviate some of the mental staleness from running all the time. The effects on physical fitness might even be a wash, but if it’s good for your mental sharpness and vitality, then it’s still a huge win. There’s another mental injury-resilience aspect I could elaborate on here too but this is already a long post.