2x20 Question

Bailsibub

Hey guys,

I'm about to embark on a month's block of 2x20 training. With the way work is, I'll be doing most of the workouts on the trainer in the mornings before I head to the office.

I've never done a 20-minute interval on a trainer, preferring to keep them shorter. But after hearing so much about them on here, I'm going to try them out.

My question is, when doing 2x20s, how often do you all usually shift up or down into higher and lower gears...to simulate undulating terrain? I've never been on terrain that was an even gradient for 20 minutes, so I'm just assuming that some shifting to simulate different force requirements is something necessary.

But is my thinking off with this? Should I just put it into a gear I'm comfortable in and hold the same cadence, making sure I'm holding my L4 wattage for the duration of the interval?

iliveonnitro

Yes.

__________________
My club: University of Illinois-Chicago Cycling

iliveonnitro

Yes. If you do it right, you wouldn't ever think to switch it up to the next hardest gear.

__________________
My club: University of Illinois-Chicago Cycling

Roadie_scum

This is an interesting and worthwhile question. Riding at a constant power on the trainer doesn't look much like riding on the road. Switching gears won't change your force requirement that much. If you are doing 'vanilla' constant power 2 X 20's, I would just find a gear that is comfortable and roll with it. You might find yourself shifting a bit to stay comfortable on the trainer - I shift a lot on the trainer, but I am a bit ADD.

Now the interesting part: as you have already worked out, isopower efforts don't really simulate road riding. They will work on your fitness in a very positive way, but it may be appropriate to switch things up a little. You can search the forum for 'micro-interval' to find out more. The basic idea is that, because the metabolic cost of effort accrues over a half-life of about 25-30 seconds, you can switch up the power in your interval to increase your neuromuscular cost and get a 'bonus' training adaption out of the session. As long as the rolling 30s average stays around your threshold, you should be able to complete the session. I believe Andy C refers to these intervals as "L4 with an L7 twist".

One problem with this type of workout is that, in the absence of high-tech trainers where you can preset the power to be constant, it's hard to control your power that well, so you work threshold but don't overdo it and force yourself to quit the interval early.

My approach would be to save the L4/L7 hybrids until you are pretty good at controlling your power on the trainer, but when doing your 'vanilla' intervals, don't be afraid to back off for a minute (like you are rolling into a corner or off a hill) and then sprint for a minute (like you are coming out of a corner and getting back to speed, or going up a little hill). This keeps things interesting and makes it more specific to your event.

dkrenik

I agree. I also recall that there was a study referenced here, or on another forum, that stated that the stochastic nature of bicycle racing is quickly adapted to in a few group rides

I'd just save them for when you can get outside.

Dave

Roadie_scum

It depends on when you actually want to be in form.

frenchyge

The undulating terrain that you might find outside not only changes the force requirement, it also typically changes the power that is applied since cadence is usually held within a comfortable range. If you're trying to ride the 2x20 workout as steady power intervals, changing gears is not really going to accomplish what you're trying to do. If you shift to a harder gear, you'll have to drop the cadence to keep power steady. As Roadie points out, you won't really be able to vary the force that much without quickly going outside the comfortable cadence range.

I do shift to my highest gear and get out of the saddle at times to stretch the back and change the loading on the legs, but that's more for a break than because I think it's simulating a road effort.

velogator

I do most of my workouts on a trainer as well (have a 9 month old baby, only time I can workout during the week is early in the morning) and had/have this same issue. I noticed that on the trainer at a constant power, I was able to get into a groove easier then when riding outside. I also found that in TT's/races the change in terrain/resistence really caused me problems, mentally, because I was not used to the change in resistence, both harder and easier. So, I started to alter the resistence on my trainer every couple of minutes during the interval to mimic change on the road. Seems to have helped, I set a PB in a 40K TT recently. Of course, you need to have a trainer that allows you to change the resistence :-). Don't know scientifically if I'm doing anything other then providing myself with a placebo effect, but I think it helps mentally prepare me for changes in resistence when actually on the road.

Roadie_scum

You are changing the demands of the workout and making it more specific. Bravo! Another consideration would be to vary your workouts more to train different energy systems.

john979

Out of the box solution: perform 8-12 30 second intervals after your 2X20s, time permitting.

dkrenik

Not quite sure what you're trying to get at here. One, or even two, "spirited" group rides per week shouldn't bring on an undesired peak. My point is that it's fairly easy to to keep (or regain) one's road/racing legs after weeks of riding in the basement with a few group rides. I'm not talking about structured Level 5 and/or 6 workouts - just getting out to "play"

Dave

Roadie_scum

That's not what I was getting at at all! What I meant was, if the OP is sufficiently time limited that he doesn't get the opportunity to train outside much at all before his target events and they are coming up relatively soon, he may want to incorporate neuromuscular training now. An undesired peak was far from my mind.