Biking for running

I do a fair amount of fairly aggressive biking as cross-training and for transportation. I figure it takes something between a 4:1 and 6:1 ratio of biking to running to exert an equivalent amount of effort.

Wow; that is surprising. That would mean that I would have to bike 32 to 48 minutes to log the equivalent one mile of easy running, assuming an 8 min per mile easy pace.

I use a time/effort to judge my bike to running. 3:1 is probably kinda close to correct for me and what I come up with. This is assuming you are road biking. Mountain biking is much different. Usually if I go for an hour easy road ride, I get in about 20 miles. One hour easy running is about 8.5 miles running for me. But with road biking you are not alway pedalling, you are coasting. So, I figure a 20 mile road ride is worth about 6-7 miles easy.

cross training wrote:

I use a time/effort to judge my bike to running. 3:1 is probably kinda close to correct for me and what I come up with. This is assuming you are road biking. Mountain biking is much different. Usually if I go for an hour easy road ride, I get in about 20 miles. One hour easy running is about 8.5 miles running for me. But with road biking you are not alway pedalling, you are coasting. So, I figure a 20 mile road ride is worth about 6-7 miles easy.

What ratio would you figure if you were on a stationary bike, pedalling constantly and perceive about the same effort as running?

Here's a link reporting results of this oft-pondered question:

http://www.thefinalsprint.com/2006/12/running-vs-cycling-which-burns-more-calories/

You'll see that the 4:1/6:1 ratio seems to be pretty accurate. Looks like this study focused on calories burned as the way to compare.

i guess it really depends on what kind of bike you have...my poorly maintained clunker easily brings the ratio much closer to 1:1. Some of those 5000 euro carbon fibre jobs easily bolt the ratio to 8-10:1...

Not if you're going by time. You can put just as much effort in on a high end bike as you can on a beater (probably a lot more on a good bike because you wouldn't be distracted by the bike and its inadequacies), the only difference would be the amount of ground you covered for that level of effort.

in ideal experimental situation maybe. As a function of terrain i doubt it. On steep uphills and downhills you would find both functional and practical limitations that make my clunker much more energy consuming that the wopper bike.

Are you a physicist?

Depends on the stat bike. The crappy ones in most gyms that have the computer on them and such put the ratio up even higher. On a stat bike like that, you usually have to work a lot harder and longer to get the equivalent to running. Usually 10 mins of riding is about 1 mi worth of effort for me. If I am on a "spinning" bike, then it might be about 8 mins to 1 mi of easy running. (my easy running is 7min/mile.)

All of this is based on my perceived effort. After years of running, cross training, and triathlons, I am usually able to tell pretty well how much work I have done. So when I get off a bike, I feel how tired I am, how much work I have done, and how far/effort I would have had to run to feel the same way.

I have my 20 year old hybrid, Trek 18 speed on a resistance trainer stand and it is easy to modulate the effort. A 60 minute ride leaves me feeling about like I do after 60 min. on the roads.

I'm planning to decrease my weekly marathon training by about 10 miles on the bike.

A trainer is pretty good actually. Mostly because you do not stop pedaling. If a 60 min run is about 8.5 miles, I would round down a little and call it maybe 6.5-7 miles. When in doubt round down, so you dont cheat yourself.

The cycling is a good cross training activity for marathon training, as it reduces the pounding. "10 miles on the bike" is that about 1 day's workout? One day off is not bad. Or if you are up to the point doing doubles, riding for about 40/45 mins (5 running miles worth) twice a week would be a decent supplement.

cross training wrote:

A trainer is pretty good actually. Mostly because you do not stop pedaling. If a 60 min run is about 8.5 miles, I would round down a little and call it maybe 6.5-7 miles. When in doubt round down, so you dont cheat yourself.

The cycling is a good cross training activity for marathon training, as it reduces the pounding. "10 miles on the bike" is that about 1 day's workout? One day off is not bad. Or if you are up to the point doing doubles, riding for about 40/45 mins (5 running miles worth) twice a week would be a decent supplement.

I have typically reached a max of about 70 mpw with an average of about 60 mpw for the last 10 to 12 weeks.

I am building after an injury and have been warming up on the bike for about 10 minutes before each run and am planning to only ride the bike for about 40 to 50 minutes on the day after my longer mid-week workout, which should reach about 90 to 100 minutes with some harder stuff included.

I am thinking that it would be a good idea to cap t 2 or 3 longest runs at 2.5 hours and add 30 min. on the bike.

That would be a total of about 90 to 100 minutes of riding on the bike, maybe an equivalent of 10 mpw. and if I can decrease my road mileage to about 50 per week I should avoid injury. It will be interesting to see how well I run the next marathon.