How much cycling is enough for cross training?

The 3:1 ratio that keeps on being mentioned here is complete BS. 24 miles on a bike is much more aerobic work than an 8 mile run. Just like running, you need to build up cycling mileage gradually or you will end up burnt out (as you are now) and injured. If you used to run 1 hour a day, biking 1 hour at the same heart rate will give you an equal aerobic workout. The only reason people tend to put more time in on the bike compared to running is not that it takes more time on a bike to get an equal workout, but because the lack of impact on a bike allows people to get more aerobic work in without risking injury. So start out doing the same time or less cycling as you used to do running for a few weeks, then you can start adding on more to get a better workout.

+1

Another +1.

If you are doing cycling as cross training, just bike for the same amount of time at a similar effort to your usual running. You don't need to ride enough to be competitive on the bike if your goals are in running.

I went for my first real ride of the year on my mountain bike yesterday, taking a break from 80-85 mpw average running on trails for the past year. Did 1:55, in the ballpark of my running times, on hilly singletrack, taking it really easy, and seemed about right. Only covered 15.4 miles too. Needed an extra 2 hours of sleep last night.

Yes, but I feel a "similar" effort is completely different on the bike versus running. When cycling, it's a burning sensation in your quads and less of an out of breath sensation (unless you're going uphill or sprinting). During a run, its a heavy, pinched pressure on the lungs and little muscular fatigue. I typically feel that a much longer bike session is required for the same effect. If I cycle for the same amount of time that I run, wouldn't I be less aerobically stressed? My prime concern is losing as little fitness as I can.

cycling sucks wrote:

Yes, but I feel a "similar" effort is completely different on the bike versus running. When cycling, it's a burning sensation in your quads and less of an out of breath sensation (unless you're going uphill or sprinting). During a run, its a heavy, pinched pressure on the lungs and little muscular fatigue. I typically feel that a much longer bike session is required for the same effect. If I cycle for the same amount of time that I run, wouldn't I be less aerobically stressed? My prime concern is losing as little fitness as I can.

I don't have an out-of-breath sensation when I run. I'm aerobically fit. A competitor once commented after a race that he knew he was toast because I wasn't breathing hard at all (and then I dropped the hammer on him ;).

cycling sucks wrote:

Yes, but I feel a "similar" effort is completely different on the bike versus running. When cycling, it's a burning sensation in your quads and less of an out of breath sensation (unless you're going uphill or sprinting). During a run, its a heavy, pinched pressure on the lungs and little muscular fatigue. I typically feel that a much longer bike session is required for the same effect. If I cycle for the same amount of time that I run, wouldn't I be less aerobically stressed? My prime concern is losing as little fitness as I can.

Try spinning faster in an easier gear. Usually sore quads is the result of low cadence. There is more muscular emphasis is on lower cadences while more cardiovascular emphasis on higher cadences for a given power.

I actually think it depends. I’ve added cycling on a trainer to supplement some aerobic base work because it’s too hot where I live in the summer.

On my easy days I run in the morning I’ve been keeping them at 8 miles in between 64-66 mins

In the afternoon I hop on the bike and cover 20 miles in an hour easily at 15-20 bpm less HR.

I could easily up the gear a little to increase the watts and get my HR where it is running and cover more than 24 miles over 64-66 mins. But that’s not really my objective right now. Just keeping HR low. Pace is 20+ because my cadence is pretty high ~95.

Keeping the bike between 3-5 hours a week while lowering running mileage 5-8 miles has been working for me. ( I have no interest running 90+ mins in high 80s-90s with high humidity)

zzzz wrote:

cycling sucks wrote:

Yes, but I feel a "similar" effort is completely different on the bike versus running. When cycling, it's a burning sensation in your quads and less of an out of breath sensation (unless you're going uphill or sprinting). During a run, its a heavy, pinched pressure on the lungs and little muscular fatigue. I typically feel that a much longer bike session is required for the same effect. If I cycle for the same amount of time that I run, wouldn't I be less aerobically stressed? My prime concern is losing as little fitness as I can.

I don't have an out-of-breath sensation when I run. I'm aerobically fit. A competitor once commented after a race that he knew he was toast because I wasn't breathing hard at all (and then I dropped the hammer on him ;).

I'm saying generally there's more emphasis on those sensations when doing either activity. But good for you whupping ass

cycling sucks wrote:

zzzz wrote:

I don't have an out-of-breath sensation when I run. I'm aerobically fit. A competitor once commented after a race that he knew he was toast because I wasn't breathing hard at all (and then I dropped the hammer on him ;).

I'm saying generally there's more emphasis on those sensations when doing either activity. But good for you whupping ass

I don't have the same associations. Just saying. My legs are what feel the effort when running.