question about biking vs running

LukerPslim

My son is a distance runner, sophomore in high school. They are doing the summer running program, and his coach said that they could substitute biking for running to change things up a bit. He told them they need 3 miles on a bike for every 1 mile running.

Is this a reasonable exchange? like, if I were to try to burn calories and get my cardio on a bike, is that a similar comparison in activity, or was that an arbitrary number the coach used?

Hornsby

I've actually heard that before. I'm not sure how accurate it is though. I usually burn around 6-700 per hour cycling. That is 20 miles or more. I usually burn around 200 calories per mile running, regardless of time, but if you figure 6 miles which is less than 1/3 of 20, that would be 1200 cals. So yea, I'm not sure it measures up in terms of caloric burn.

scottb81

That is reasonable as it will result in a similar quantity (timewise) of aerobic exercise.

headwind2015

It is a reasonable exchange. When I was running triathlons in college we would substitute longer rides that were the equivalent time allotment to our race distances all the time.

Cycling is a great form of cross-training for runners and a good way to mix things up to prevent overuse injuries. The trick is hitting the right intensity on the bike; group rides can become social in a way that running workouts never do. (maybe that is just me)

LukerPslim

thanks everyone.

I am guessing with my son, the pace on the bike wont match the intensity of his running. He is a bit too social, and is riding much more casually than he needs to be, but, at least he is out being active.....

scottb81

A heart rate monitor could help him with getting the right intensity although heartrates on the bike will be around 10 bpm lower than running.

mwyvr

Casual riding burns far fewer calories per unit of time... Probably need to double or triple the 3X mileage factor quoted.

msf74

What average speed does your son usually ride at during his training? If it's anywhere between 15-20 mph I think somewhere between 3.5-3x is about right. Any quicker than that and it's more like 2.5 IIRC due to the affect of wind resistance.

I'm presuming he doesn't have access to a power meter?

Ohhim

I'm around 80-120/mile running, and 25-40/mile biking (per speed/climb). Sounds right.

beemerphile1

Sounds reasonable at 3 to 1 ratio. When running, you are carrying your weight, when biking the bicycle is carrying your weight.

I do both and I can probably bicycle 10 times the miles I can run.

headwind2015

mwyvr wrote: »

Casual riding burns far fewer calories per unit of time... Probably need to double or triple the 3X mileage factor quoted.

So you're recommending a 9:1 ratio of riding to running? I that number is much to high. For example:

I run a 8:20ish mile pace for a flat 10k...roughly 52 minutes. My, solo, cycling pace 17.6ish MPH over flat terrain (with some rollers). With a 9:1 ratio, I'd have to ride 56 miles which is more than 3 hours of riding for a 50 minute race. That is overkill, in my opinion.

There is something to be said for putting in your base-mileage, but that question wasn't asked.

BrianSharpe

Sounds about right......and cycling is great x-training for runners.

mwyvr

Note I said casual. I also said double OR triple.

17mph / 27km/h isn't casual.

I see devices and apps over report cycling calories all the time. Strava once reported 1,800 calories for a dead slow group ride. Yeah it was 36km but no way was the calorie burn that high for such a leisurely pace, which is what I was pointing out in my note.

When the pace is quicker I find Strava and my Garmin GPS tend to be closer together in result and the burn reported makes more sense.

Working backwards using the three to one ratio, 1800/3 is to 36/3 = 600 calories for 12km running. That is too low for this runner although if a rough guide is all you got to go with, it's better than nothing.

fbinsc

Good question. I think a century ride on a bike is a hell of a lot easier than a marathon. On effort basis I'd have it as more than 4:1 cycling to running if you go by distance.

I'd just go by perceived effort personally...too easy to debate all the other possibilities.

kristinegift

That's pretty reasonable. If I want to make up for a 3 mile run, say, I do about 8 miles on a bike.

Huppdiwupp

It will depend a lot on the amount of ascent. If I go cycling, I tend to seek out very hilly routes, where the difference per mile is less. Also, the equivalence may apply to calorie expenditure, but if your goal is to run, cycling is not very specific, as it uses different muscles. You can swap a recovery run for a recovery ride, but you don't get all the benefits from a running workout.

headwind2015

Obviously any exercise that isn't running isn't going to be the same as running.

Also, cycling and running use many of the same muscles. The difference is in the mechanics. (How those muscles are used)

In the original post it sounds like cycling is going to be used as a form of cross training to augment running. Cycling is a great option for this person.