Bike Trainer Math
3331
Member
1318 days
RV posted 1 year ago.
1.5 times seems a bit high.
I go off of something that was on one of the Spinervals workouts and that was that a 3 hour spinerval session equated to about 4 hours on the road. Guess that is 1.33 times. I only really apply that if going 2 hours or more on the trainer. Less than that I assume it is 1 to 1.
I guess it all comes down to how hard you are working. If spinning easy then I don't think it applies. If going steady-hard for long enough then it does.
RV
It takes a long time to get good. - Scott Molina
Slow is smooth; smooth is fast. - Rich Strauss
478
Member
1380 days
kona_expat posted 1 year ago.
Riding=riding, no matter where you do it. If you use a power meter, you can calculate the "value" of a ride, so if you noodle around outside for 2 hours, but really punch it for 1 hour inside, it's possible for those 2 rides to have the same TSS (training stress score).
The 1.5:1 outdoor:indoor time ratio rule of thumb is more to help with the mental stress of the potential boredom of trainer riding.
During the winter, I only spend about 5 hours a week on the trainer, but it's very high quality time. Still, 5 hours=5 hours. My outdoor rides are just as focused, but at least when I come out the door in the spring, I am in much better shape than someone who is less focused on the trainer.
I've read about folks in northern US who trained for IMAZ, and face it, if you are doing IM at some point you need to build the endurance to ride 112 miles strongly. So you would need to do it on the trainer if you can't get outside to do it.
It all comes down to how you structure your indoor time. If you live in cold winter, though, you may as well use those months to have a run and swim focus, and on the trainer, use the time to do workouts that work towards raising your threshold power. I got a lot of bang for my buck out of 5 or less hours per week through March (2 x 1:30, 1 x 2:00), and was able to hit 4+ hour rides outdoors just fine.
In my training log, 2 hours is 2 hours, regardless of where it happens! But let's say it's April and I'm supposed to do a 4 hour ride and it's rainy and cold outside, so I decide to ride on the trainer. I might only go for 3 hours, making sure to get the quality intervals in, or 3:30, depending on how I feel. It's not worth it to sweat that stuff.
I heard from a friend that time on the trainer comes out to about 1.5 times longer than time spent on the road. Is this true? I'm asking this because with the remnants of Hurricane/Tropical Storm Ernesto turning much of North Carolina and the Southeast into a mud pit I had to spend some time with my trainer this morning, which I hate. I had planned on riding 40miles this morning outside but didn't really want to go out and deal with the wind and rain (I did that yesterday, had a great time all by myself but I was covered in dirt and busted my ass on a brick crosswalk- fortunately I was just minutes from my dorm and "cooling down."). Instead of going outside I did 2hrs on the trainer with a few spin-ups, gear-mashing intervals and long steady "riding" to work on positioning and cadence. So, in actuality would my 2hr trainer session come out to a 2hr40min road ride? Just wondering.
"I run because it always takes me where I want to go" -Dean Karnazes