cvcman

I havent been able to run for 5 weeks due to a tendon issue...Im going to PT for it so I have been bikng at least 25 miles everyday and I avg 19mph. When I ws running I was doing 5 miles every other day and biking on the oppisite days

Now he has me bike 2 miles, then chg shoes and run 1 mile, so I bike everyday and run 1 mile after biking every other day...now running the 1 mile AFTER the biking seems as hard as running the 5 miles alone...

My ? is if I bike at that speed for 25 miles how many miles would that be in running miles, or aprox ??

Bah Humbug

It's very, very hard to compare, but the closest you'll get, normally, is somewhere between 4 and 5 to 1, biking to running. It is, however, extremely inexact, and you can never use one to substitute for the other unless you're just looking for general fitness/ calorie burn.

cvcman

So probably the lack of running for 5 weeks is why im seeing it be hard to run the 1 mile or....because im doing it after biking 25 miles which COULD be like running 5 miles then trying to add another mile ?

canam73

What part of the running is difficult?

If it's cardio then it might be because you are running with higher exertion than you typically ride at.

But if it's your legs it could just be because running uses a different muscles and a wider range of motion and you need to re-adjust yourself to it.

gregf83 

The reason your 1 mile hurts now is because you haven't been running not because you rode 25 miles before the run. Biking 25 or 100 miles will help your cardio-vascular system similar to running, but it will do nothing to prepare your joints and muscles for running.

The bottom line is you will need to run to build up your running endurance. Cycling won't help much unless you're unfit.

cvcman

it just seems like NOW when I run 1 mile AFTER biking fairly fast for 25 miles that my wind is not as good as it used to be when I just ran 5 miles w/o biking ?? My legs are not tired its just y breathing seems harder,again more lke I am running 5 miles rather than just 1

PatrickGSR94

Joints, muscles, etc. aside, I think whatever speed on a bike that lets you sustain a certain heart rate will be about equal to whatever speed/distance running you can do that sustains that same HR. So of course it can vary depending on terrain, winds, and other factors. In other words, there is no concrete answer.

StanSeven

I think the 5 to 1 is about right. It's so easy to not maintain the same intensity cycling. Most of the time you start off slow, there are intersections, traffic lights, cars, people, and coasting/slacking off going down hill, etc. Running involves a much harder start and you (or least I) can maintain the pace the entire time by running through intersections, against traffic, etc.

PatrickGSR94

For me, running is much easier at the start because my heart and lungs aren't strained. At my current fitness level, I can run for about 2 miles SLOWLY, but continuous or near so. And by slow I'm talking 15 min/mile or 4 MPH. That's about the best I can do right now. But cycling I can go for over 20 miles at 13 mph average (still slow, but best I can do), which does include a few stops, coasting, etc.

deacon mark

As a runner and cyclist it is about 5 miles to 1. I can ride a hard 50 miles for me that might be 19-20 mph on a flattish course. Running a hard 10 miles in 82
minutes leaves me much more spent. Recovery from cycling is much quicker. I normally run 35-40 miles a week and ride 80-100. If did not run and had the time riding 40 a day would not be difficult.

DGlenday

As unscientific and subjective as these comparisons are, I still find them interesting.

I was a big runner 35 years ago - but haven't been on the pavement for years.

In a conversation with some cycling buddies a while ago I was saying that it seemed to me that running a marathon would be way harder than riding a fast century. One of the guys surprised me - said that he's run over 20 marathons, and felt that riding a fast century was far harder than running a marathon.

Either way - if you believe that the 5-to-1 ratio is about right, then I'll be close to "running a marathon" in 2 weeks time, when I do a 200km (125 mile) timed ride. Funny - I've never thought of myself as being in the same league as marathon runners

hhnngg1

I'm currently a triathlete. Was a pure runner before that and briefly a pure roadie.

I am equally good at run and bike according to my race placements. I can average just about 23mph for a 40k and then run 6:30min/mile for a 10k right after it. (My swimming is significantly worse.) I train a bit more on the bike than run beacuse triathlon favors the bike, but I still log about 110-140mpw on the bike and about 35-40mpw on the run for most of half-ironman training.

I don't think improving your bike will help your running much. The cardio overlaps, but the pounding is invariably the limiter. Running actually will overlap and help your cycling, but it doesn't do much once you're up to racing speeds (like 20mph+ for a 40k TT). Without the power of the legs to push high speeds on the bike, you'll always be limited as how fast you can go.

My ratio is about much lower - just less than 3:1 in terms of TIME. In moderate training, I'll run about 7-8 miles in an hour, and for the same effort, ride about 18-19mph on rolling hill courses of similar elevation. My lower ratio is probably due to my faster run speed; obviously a 5:1 ratio would equal about 35-40 miles in an hour on the bike, which is ridiculous. However, as said, I'm not disproportionately stronger on the bike - I'm pretty similar in both in triathlon racing placement.

Again, do not expect cycling to maintain your running legs. It will help with the cardio, but unless you're a noob cyclist, you will probably not notice the cardio maintenance since your run legs will be so deconditioned from lack of run pounding that you won't be cardio limited. There's definitely no such thing as saying a 2 hour bike workout is equivalent to a 40 minute run workout. THere are overlaps, but in the end, it's different enough that you really can't compare the two. You'd get horrible results training for a century by running and even worse results racing a marathon by cycle training.

And I as well as the vast majority of experienced runners/triathletes can say with absolute confidence that a marathon takes a MUCH bigger toll on the body than a century. Marathons are hard enough on the body that there are no professional runners who will race them back to back within a month, orrarely, two months, due to the injury risk from pounding. In contrast, pro cyclists do big miles on multiday tours all the time. This doesn't mean that marathons are harder than centuries - obviously if you're racing, it depends on who shows up. But for sure, the toll on the body from a marathon far exceeds that of a century, which for most people makes them much harder to race.

Bah Humbug

And that is why I stick to sprint and Olympic tris - can just race them back to back weekends, days, or however much you want. Not like an IM...

StanSeven

There are exceptions to running marathons frequently. Here's a local DC guy who does well

https://en.wikipedia.org/wiki/Michael_Wardian

Michael Wardian (born April 12, 1974) is an American marathoner and ultra-marathoner. He won the 2008, 2009 and 2010 US 50 km championships.[1] In 2008, he won the U.S. National 100 km championship.[2] Wardian also is the 2007 JFK 50 Mile winner, and won the National Marathon (now known as the Rock 'n' Roll USA Marathon) in Washington D.C. three consecutive years (2006–2008), and in 2010, 2011 and 2012.[3][4][5][6][7]

Wardian is known for the vast number of marathons he participates in. During a 45 day span in 2006, Wardian won four out of five marathons he raced.[8] In 2007, he ran 13 marathons (not including ultra-marathons), and seven marathons in a span of nine weeks (winning three).[9] March 2008 saw Wardian win the National Marathon in Washington D.C. on a Saturday, and then finish third at a marathon in Knoxville, Tennessee the very next day.[10] In 2008, Wardian ran a total of 53 races.[11] Wardian frequently participates in local races in the Washington D.C. area.[12]

cvcman

wonder how the Tabata figures in...I do Tabata on my stationary bike but its only a 4 minute workout...

hhnngg1

Wardian (and many others) do well in marathons - but also keep in mind that Wardian is still not considered a top elite professional marathon runner. He is elite for amateurs, but he never really came close to even qualifying for the Olympic team in marathon.

He probably hammers it day in day out, but most people who actually run all-out marathons are at sky-high risk of injury in the weeks post-race. The marathon forums are littered with stories of people who felt great, kept training and racing,and then got a stress fx or some other strain.

The marathon maniacs group is a list of hundreds, if not thousands of people who run back to back marathons, often days or weeks apart. These folks are definitely in the minority, and there is no professional running coach who will expect their amateurs, even the strongest ones, to race back to back marathons, even weeks apart, for true PRs.

bikepro

In one of the first books on aerobic training, Dr Cooper included a table of "Aerobic Points" for various activities. For aerobic points, riding four miles was approximately the same as running one mile. But then, it depends on your basis of comparison. You don't hear about Cooper much any more, but he was a pioneer going back to the 60's and 70's.

https://www.cooperaerobics.com/Cooper-Clinic.aspx

Lexi01

Bit off topic I know...but...

A mate of mine just got back from racing an IM in Kona...he had a t-shirt that reads "You did a marathon - how cute". Hilarious.

But as a friend of mine says running is awesome training for cycling...but cycling does squat for your running.

hhnngg1

Off topic, but the standalone marathon beatdown and effort is well know by experienced IM/marathon competitors to be much harder than the ironman marathon if run all-out. Sounds weird and counterintuitive, but it's because in a standalone marathon, you'l be pushing your body to the brink and then more over 26.2 miles, running at a fast pace if you've put your training in. It's a huge toll on the body and usually demands weeks of recovery time.

In contrast, the ironman marathon, while very hard because of the swim/bike preceding, is run at a significantly slower pace than your personal best. On average, a GOOD showing is a 15-20 minute slowdown from your standalone marathon. It's unbelievalby fatiguing, but actually easier on your body than the standalone marathon in terms of pounding stresses. As a result, a lot of ironman training programs, including elite ones, max out the long run at 18 miles, where as the vast majority of standalone marathon training programs max the long run at 22 miles. This difference has nothing to do with being too tired to train off the bike and everything to do with the different speed of the IM vs standalone marathon.

On slowtwitch.com recently, I saw a poll where a lot of really fast elite triathletes said they felt more beat up after a pure standalone marathon than their ironman.

hhnngg1

This would assume that you aren't limited by your musculoskeletal system, so that you could tap in to the full cardiac reserve.

Unfortunately in running, the majority of noncompetitive runners are limited by their legs and the ability to turn them over and withstand the stresses of running at speed, rather than their cardio. You could have world-class aerobic system but if your musculoskeletal system can't keep up, it's all for naught. This is particularly true in running.

Again, for me, if I was doing a 4:1 bike to run ratio, since I can easily run 7-8 miles in an hour at training (not racing) pace, that would mean I'd have to ride 28-32mph for training paces on the bike. Not gonna happen. Just shows how these mileage estimates aren't good since you're really comparing apples to oranges. (Although it is definitely true that most folks have an easier time going from run to bike just because the pounding forces are higher in running and give more injuries to cyclists when they try and switch.)

StanSeven

Usually when this comparison is made, there's no standard. You're using time but most people use subjective means or calories burned or something similar. I used 5:1 just because that's the way I feel afterwards. If time was the standard, I would change to something like 2.5:1.

cbresciani

IMO running is way harder than cycling. I would bet that most members of this forum can ride 50 miles at a brisk pace, say 15 to 17mph, with some or minimal effort on a fairly flat course.

But take that same member and have them run 10 miles on a fairly flat course at a brisk pace, which would be about a 9:30 to 10:00 minute pace per mile and I would bet they would have a way harder time. If they could even do it to begin with.

i have run 4 half marathons in the last 2 years so I'm not speaking about something I don't know.

Dilberto

OP - try Mountain Biking. You'll get all the cardio, including the hi-intensity intervals with the steep pitches MTB climbing brings. Plus, the technical aspect of MTB will hone your bike handling skills to the max.

jsutkeepspining

i would say their equally hard aerobically, but running is much harder on you. theres a reason a long run is only 2-4 hours and a long ride could be 7 + hours.

also on the note about brisk runnign versus brisk riding, if u give someone time to run and get acclimated they should be fine, its just like transitioning to riding long distance. It isnt hard, it jsut takes alittle time.

mprelaw

I've run marathons under 3 hours. In my late 20s. I could also break 60 minutes in a 10 miler.

I just averaged 18 mph for a century with almost 4000' of climbing in September. At age 59.

I heaved my guts during the last marathon that I ever ran.

I finished that century comfortably. I don't think that I even came close to going into oxygen debt.