Fastest 20 miles-cycling

Ride lots.

Seriously.  Get up to 100 miles a week, hills, flats, intervals if you want.  There is no secret to getting faster on the bike other than riding a heck of a lot.  Ride with people faster than you.  Get dropped a little later each week (that's how I, and I suspect lots of others, got started)

With the asterisk - there may be equipment choices you can improve on to go faster, i.e. tri bike vs. road bike, materials, or there may be weight you can lose....There are three things that slow you down on the bike - wind (get aero), gravity (get light) and friction (keep bike in good working order).  

But assuming these things are relatively in order, just ride.

^^^Pretty much this^^^

As far as "junk miles" go...they have a place assuming you're hitting the intensity on your hard days.  Most triathletes only have time to ride 2-4x a week, so there really isn't much need for easy rides or junk miles.  Maybe one ride if you're doing 4x per week.  But if you're like me and all you do is ride...there is no way you can ride hard 7 days a week without burning out or having your hard days not be as hard.  So you have to supplement your hard days with some easy days.  

The overall key though is making sure you hit those hard days hard.  That is going to be your bread and butter...everything else you can fit in is gravy.

It's actually not as complicated as it seems for AGesr

- Ride more, lots preferably. Any extra mileage helps. 

- One or more of those weekly workouts should be a seriously hard effort. You may have to work up to getting the fitness to do these, but once your bike volume is high enough that you're not gaining speed anymore by just adding more moderate easy efforts, you really have to dial up the intensity to teach your legs to put out more power for longer. Sufferfest videos are a good choice for regularly hammering yourself at very intensities. 

Cycling is slightly different than running in that riding lots of easy miles won't necessarily pick up your top-end speed to the degree it does in running, where you can absolutely just run LOTS at moderate paces only and still set PRs at 5ks and 10ks. 

I ride a fair amount of short sessions. Half an hour commutes to work. But in all of these I ensure there is some quality time. And at least once a week I go off to either climb a big hill, or I try to TT to whole session. Sometimes I will pick 2 or 3 km and try to hold a high cadence in a bigger gear than normal.

They aren't so different.  If you went out and rode lots of easy miles, you'd see similar improvements like you would see in running a ton of easy miles.  It just depends on what your definition of "lots" is for cycling.  I'd probably start in the 200+ mpw range.  Put in 12 hours a week at 65% of FTP (42 TSS points per hour) and you'll build up lots of good fitness over the guy who's only riding 4 hours a week averaging 80 TSS per hour.

Not saying that's a good way to manage your time...just that it's possible, and not so different from runners who choose lots of intensity and only 20-25 mpw, and the runner who runs all easy at 50-60 mpw.

I def disagree with the concept that cycling easy will yield as large dividends as running for a high-power cycling event such as a fast 20 mile ride. Running is both weight bearing and our brains/spinal cords as humans naturally accelerate the neuromuscular adaptations as we run more. 

Riding easy all the time will improve you , but after a certain point, you'll find that your top end speed for hi-intensity racing (like a 20 mile TT) is going to have really diminishing returns, even if you can rider for longer and longer distances. The high wattage interval training addresses this by pulling up your top-end of peak power. 

We have a local recreational cycling club here with a lot of 'everyday' cyclists who log easily 50 miles per day, if not 70 miles per day during parts of the season, 6-7 days per week year round, but it's all done at easy pace, no hammering. They do great on stuff centuries and double centuries (in fact, the longer the better), but they aren't even as good as a MOP male triathlete at a 20mile TT since they never train at those higher powers. 

Almost all 40k type TT training programs incorporate threshold and suprathreshold intervals on a weekly basis for exactly this reason.  

Quantify "easy"

Exactly.  I stated 65% of FTP, which is still on the lower end of Z2 that can extend up to 75%.  Do a ton of miles at that intensity and you will get tired and build good fitness.  My guess is that these cyclists Yaz is speaking of ride much lower than Z2.

With running, think of it like someone who can run a 20 minute 5k.  Doing a ton of Z2 miles at 9 miinute mile pace will help them.  But doing a crap ton of miles at 13-15 minute miles isn't going to be as effective.  The difference with cycling and running is that it's almost impossible for a fit runner to train at 13-15 minute miles because it's too awkward...but a cyclist can easily noodle around at a ridiculously easy effort without it feeling awkward.  So you can't really compare the two examples unless you have the context and quantifying how easy each is actually going.

I do agree that if you want to be competitive at cycling, you do need to put in some harder efforts to raise the roof of your aerobic capacity.  But the same goes for running as well.  So they aren't so different.  Most people could work themselves to a 20 minute 5k just on Z2 effort volume, just like someone could work themselves to around a 24 mph average on a 40k TT on a lot of Z2 mileage.  But unless you win the genetic lottery, you're not going to run a 16 minute 5k or ride a 52 minute 40k on just Z2 efforts.

And just to be clear, I do advocate using intensity into everyone's cycling training plan as it's your best use of time and recovery...especially since the injury risks of cycling intensity are lower.  Just pointing out that the idea of "easy" running and cycling are not as different as you think they are.

Very much what I was thinking. There are some noteworthy differences, but some important underlying principles are very much the same.

Another things to note, to keep the progress going, the lots really has to be LOTS. And also what it takes to build into a particular race vs raising your overall fitness. Some earlier examples conflate the two. What's being discussed here is more the raising vs optimizing for a race.

Having said that I would also advocate for the incorporation of faster/harder work in both running and riding to get the best results.

My impression (perhaps wrong) is that the OP is new/relatively new to cycling?  If so, just my ,02, but I think at that point in a cyclist's development working on T.I.T.S. as opposed to any specific interval is higher on the priority list (not that intervals aren't, but if 20 miles is your long ride, as mine once was, you have a long way to go to maximize that distance)

I think perhaps the responses are geared towards a cyclist wth say 2-3 years of 3000+ miles, and developing that TT speed.

But i could be wrong 

If you've been an avid runner- then you're no stranger to training, and the benefits of consistency and volume.  That part is the same.

But here's the important difference between the two sports, from a training philosophy:

Running:  Mostly Easy, sometimes hard.

Cycling:  Sometimes hard, sometimes easy.

In comparison to running, you can put in more intensity on the bike, as the results are not as risky, injury wise.  You're not dealing with the eccentric pounding of running, so you get to put in longer stretches of threshold work, and above-threshold intervals.  So, in that regard, no.  it's not exactly the same as run training.  Also, with running, you get benefit from easy miles- that's where you're giving all that connective tissue (ligaments, tendons, joints) a chance to gently get beaten down so they recover.  Easy cycling, other than building up your saddle bones, doesn't buy you much.

After a couple months of cycling training- you should be able to lay down a 90+% 2hr threshold ride, and be able to ride hard again in a few days.  Do that running- and you'll need two weeks to recover.  (or, at least I do)

Easy riding can build up quite a bit, but it does take more of it as there is less development for a given amount of time. Where it makes that up is in being able to ride a whole lot more and develop a greater training response withe the volume. Running does have the additional benefit of the body conditioning being much greater, but the cycling isn't nothing.

Do keep in mind though, that the amount of easy prescribed in a training regimen would also depend on the amount of training being done. Some people I've followed may only ride 2-3 times a week and 40-60' at a time. For this low of volume, I would have various types of intervals in every workout with the lowest being in sweet spot. The reason being that there isn't really anything that develops at an easy effort that doesn't also develop at least as much as you go harder given the same amount of time spent riding. Up until about threshold, and then things can shift around. There will still be easy in the warm-up, cool-down, and recovery sections of these.

Still would be fine for some to take the occasional ride as all easy and just enjoy being on the bike and not have to suffer every single time.

There still is definitely a difference between the rewards of 'easy' running vs 'easy' cycling, meaning z2 or even lowz3 training.

You'll still improve in cycling with more volume at these z2 levels, but it will definitely be less than your improvement in running. As I mentioned before, it's because of both the weight bearing and impact aspect of running, which will intrinsically place more of a load on your muscular endurance at z2, as well as the human's brain's natural ability to adapt neuromuscularly to running even at lower aerobic levels - human brains are evolutionary wired to improve our running the moment we do more of it. It really is a unique adaptation for us, meaning other activities, including cycling, don't get this neuromuscular bonus.

And when you start talking about 'fastest 20 miles in cycling' as the OP's thread is titled, you really leave a lot on the table if you don't incorporate much higher power (like threshold+) power into your training at some point. Of course, bike beginners will have to work up to it, but you can push these harder workouts on cyclists earlier and faster due to less injury risk than on runners, and you actually should be doing more higher power work on the bike for your fastest possible 20 mile TT because of the reduced injury risk. 

Doing lots of time in the saddle at z2 does help, but after a certain level that isn't ridiculously high in volume, you will likely get even better results on the bike for a 20 mile TT with less volume and more intensity. Note that this advice pertains to 20 mile TTs (around an hour or shorter max efforts) - if you're training for longer stuff like bike centuries of even half ironman volume, the time in the saddle will have more importance and impact on your results than it would for a 20 mile TT.

Well then, good. That's sounding more like what was being said. Differences sure, but don't have to totally relearn things between the two.

Only working about one intensity range is not really best for any type of race I'm familiar with. It takes a variety of intensities. The century riders (or longer) would still do well to add higher intensity rides at times, as was stated a few times. And that can be flipped for the shorter racers. They can do well with the shorter, intense rides, but could also add in more volume and do even better. Everyone will run into limitations by only riding around about the same intensity all the time. Some of what's being said is trying to say too much at once. To really develop a lot it would be good to look much bigger than a single upcoming race. This goes back to the conflating comment I made earlier, looking at overall aerobic fitness vs building to a single race. Work on all aspects of the aerobic system over a longer period of time (think more through the entire year, or even longer) and then stress the specific areas needed leading into a particular race. After the race, take a look at the more general aerobic fitness again and do what is needed to raise that up.

Take out the lingo.  Training for running and biking aren't THAT different.  As noted by many above, there is a bit less to be gained by riding easy versus running easy.  And, as importantly, it is a bit easier to ride harder and recover for the next workout than it is with running.  (The main reason for both is the weight-bearing, impact nature of running vs riding.)  There is no one-size fits all training program, but in general, you should likely include more intensity in your riding program than you would in a similar running program.  Use some shorter intervals (akin to 'track work' in running) and some longer ones (akin to 'tempo' or 'pace' runs) to add variety to your 'hard' work.

There used to be a poster on BT who would always chime in with the running advice of:  run lots, mostly easy, sometimes hard. 

For cycling, I like to think the analogous advice to be:  ride lots, often hard, sometimes easy.

It need not be more complicated than that unless you want to make it so.  As you continue to ride more, you will learn how often you can go hard (and how hard) while maintaining your overall training.  If it becomes too much, back off.  If you feel like you are handling it well, push a little harder and see how it goes. 

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