By Martin Sigrist
So far we have seen how knowing your power zones can provide you with insights on your strengths/weaknesses and allow you to plan for an event. However the most frequent use for power zones is for training.
This is because they add purpose. Instead of just going out for a spin you can ride knowing it will make you more able to cope with the last few miles of a century (zone 2), climbing Alpe D’Huez in an hour (zone 4) or winning out in a final bunch sprint (zone 7).
Zones can guide training in three key ways
- Providing clear targets allowing you to prepare a plan that, if followed, will maximize the likelihood of improving
- Giving instant feedback during a workout on how you are performing versus your plan
- Providing a history that will allow you to see what has and has not worked for you which in turn will allow you to improve your planning for the future.
Exactly how to best use them can get complicated and with there are differences in opinion on the ideal approach*, still the outline will be common for all cases.
Step 1: Pick and prioritize zones: This should naturally follow from your assessment of your strengths/weaknesses versus event priorities.
Step 2. Using step 1 as input, allocate zones to training days in a training calendar. Each month could have an overarching focus. For example, a 3 month lead-up to an event may have month 1 being be primarily about improving zone 2, month 2 about zone 4 and month 3 focused on zone 7. Then, specific workouts (which we’ll cover shortly) will be allocated day by day matching this, with each typically having one zone as a main focus, perhaps with others as a secondary objective.
Step 3. Test progress and revise plan if necessary. One advantage of power based training is that you can easily see if you are making progress as your wattage increases. Still, as suggested earlier, it is useful to schedule tests on a regular basis as these not only act as a progress check but also as a motivator. The exact format of the test does not actually matter too much so long as it forces you to the maximum effort in a priority zone. If you can find a form of racing that does this then it can be especially helpful as it not only produces a test number but also all the other aspects of riding beyond power such as bike handling in a group and nutrition. The results of these tests may lead to changes in the plan as will other circumstances such as unexpected time off.
* Most of the differences between training approaches are about the relative amounts of time you should spend in each zone and when, exactly, they should best be scheduled. Given the huge variability in terms of natural aptitude, goals and training time there is no single best method One advantage of using a power meter is that it gives you a very clear view on what you expect to see when in terms of improvement, so you will quickly see if the plan you are following is right for you.
Workouts come in literally thousands of variations, however they boil down to four fundamental types.
All Out Efforts With Full Recovery
The archetype for this type of workout is Zone 7 sprints. While other aspects of sprinting (such as bike handling and high cadence) can be trained with sub maximum drills or gym work this zone has to include sessions where you go absolutely all out as hard as you can then recover, fully resting (for 5-10 minutes) afterwards.
The reason why this is necessary is that the fuel needed for these efforts is all used up in a few seconds and takes a while to replenish (and this replenishment happens best if you are fully resting). On top of this your body needs to adapt to the immense amounts of stress these efforts put on it and it will only do so under full load. This sort of session is less common, indeed rare for other zones except for testing. Still, if time permits, a way to add variety for zone 5 and 6 is to choose a segment of some sort, go all out, give yourself plenty of time to recover, then try to go harder/faster.
Most zone 5 and 6 workouts and many zone 4 workouts will use this format. The principle is simple, accumulate time in the target zone by working hard, easing off (typically for as long as you worked for zones 5/6 and 5 minutes for zone 4) then working hard again and repeating until you are not capable of working hard enough to hit the target zone. Then recover for several minutes and repeat as time, body and mind permit. (Recovery in this case is best done spinning very easily, since this speeds up to clearance of the waste products which cause fatigue.)
Power meters are particularly suited for this sort of training, as they give you precise information about what you need to be doing, when to stop and how you are coping.
Your test results form the basis for this. While you will not be able to hit 100% of your best power for 100% of the duration you should be able to do a little less, say 95% for 95%. Don’t get locked into the same target every ride — add variety. Sometimes see how much power you can hold for 105% of the time, sometimes how much more power you can do for 90%.
In a typical interval session, following a warmup, you will use the first couple of intervals to set a benchmark watt/duration target then continue until the power you can hold drops too low under this (5% for a 5 minute effort and 10-15% for one minute efforts is a useful rule of thumb). Then, if time permits, repeat.
Another way power is useful for these workouts is that you can vary how hard you work during the interval. One option is “peak and fade” where you go hard at the start with the expectation you will weaken but not stop by then end. Another is “steady state” where you try to hold the watts number static from start to finish, another is a “smile” (because it looks like a U not because it is fun!) where you go hard for the first few seconds, ease back then go hard again at the end. This approach adds variety and also habituates mind and body to the variability that will inevitably occur in real events.
This is the norm for levels 2 and 3. It is also an effective way to develop zone 4, in what is known as the “sweetspot” (85-95% of your zone 4 power).
The objective for these workouts is, after a brief warmup, hold average power steady in the target zone for the full duration of the ride (so for “sweetspot” an hour or so, zone 3 for 2 to 3 hours, and zone 2 for 3 to as many hours as you can). This does not mean you cannot ever stray into other zones, but you will aim to keep these to a minimum, most especially avoiding freewheeling and zone 1. The other objective of these workouts is to finish strong, aiming for a “negative split” so that the average power for the second half of the ride is higher than the first. This takes practice, but is essential especially if your target is a longer distance event.
Heart rate monitors can provide a useful performance measure for these workouts. If you calculate and compare average power/average heart rate for the first and second halves of the ride you will find that this value goes up (this is called “cardiac drift”). As you become fitter then this rise should become less. As a very rough rule of thumb a rise of less than 5% indicates a good level of endurance fitness. These workouts can also be used to test nutrition, it can be useful to check both how little you need to eat in order to hold target power and, occasionally, aim to eat 60g of carbohydrate per hour to see if your stomach can handle this amount and if it makes you feel any stronger.
At zone 2, these rides can be boring. It may sound weird, but to an extent this is a good thing. There is a lot of evidence that your mind gives up before your legs (Alex Hutchinson’’s book “Endure” is a great read on this topic: https://amzn.to/2XibKlj) and one factor that can lead to this happening is, put bluntly, the monotony of riding slowly. So just like everything else you need to train for this.
One suggestion already mentioned is use feeding as a stimulus, rewarding yourself with some sugar every few miles. This can break up the ride and ingrain good habits. Even top professionals can forget to eat in the excitement of competition.
Occasionally you can add variety by planning some spikes into different zones every now and then (say 2 minutes of zone 5 every 15 minutes). Aside from spicing things up a bit, these help adaptation since one key purpose of these rides is to get muscles used to clearing the waste that builds up over time spent in zones 4-6.
Between intervals you should ride very easy at zone 1 recovery pace. Professionals and others who train 6/7 days a week will also plan workouts that are entirely in zone 1, since it helps the recovery process. Recreational riders will typically not plan these workouts as training rides they do not result in any fitness gains for time spent. Of course they can still be done for fun and slower paced group rides with a coffee stop might well fit into this category.
Mixing Up Workouts
The workouts about are the fundamentals but they can and should be mixed up. Here are a few suggestions
- Sometimes ride “power “blind”. A potential danger (literally) with power training is getting fixated on numbers appearing on your bike computer. It is good practice to do workouts, every now and then, with your watts out of sight. After the ride you can see if you hit your target zones and may well surprise yourself by finding you have put out more power than you expected.
- Do not feel every workout has to be at prescribed watts. Every workout should start with a warmup and an assessment phase during the first few intervals or minutes where you sense check that the target is appropriate. You may be feeling rough for some reason or other and have to cut watts or even do an easier workout. But it can also go the other way. Some of my best ever rides, including a recent all time best 20 minute effort done with a Xmas hangover, have been done when least expected.
- Use workouts as race simulations. Most workouts will typically focus on one zone, but it can add variety to plan to hit several zones. One especially good way to do this is to simulate your event, say by planning some zone 5 “smile” intervals after a couple of hours at zone 3, recreating hitting a few hard climbs at the end of a race. Power on these may well be down on what you can manage while fresh but this is important information for your pacing strategy. Even more value can be added by stacking mental toughness routines on top of this e.g. visualization. (Professional riders competing on grand tours take this idea a step further by having a separate set of zones for their power after having burned 2000-3000kcal since these are the numbers that will decide who wins. This may be overkill for amateurs, but can be a useful way to analyze the power data from an actual race. If you find your zone 6 power is hugely down in the last minute of a race compared to your numbers when fresh your training priority might be zone 2 or 3, feeding better and/or learning to do less work in groups. )
- Or alternatively, you can use races as workouts. Entering races with the specific intention of using them as workouts for a particular zone can be a good way to train and be great fun too. I tried my hand at road racing, but with my sprint had zero chance of winning in a bunch. I still took part, with the plan of using them as zone 5 and zone 4 workouts, aiming just to break from the front then ride as hard as possible until caught. Most often I was swallowed up of course, but I still had some great power numbers as compensation. And sometimes, though rarely, others joined and we made it to the finish first. The main reason for not doing this used to be the time, expense and hassle involved. That is much less the case now that Zwift racing is an option. If you have not tried entering Zwift races as a means of doing workouts, I would recommend giving it a try.
Power Zones Conclusion
Hopefully this article has helped explain what power zones are.
There is more, quite a bit more that a power meter can do, but zones are an essential part regardless of how far you want to go down the route of realizing its full potential.
The most important thing is that zones should help you answer three questions essential to success:
- “How fit am I now?”
- “How fit do I need to be in order to hit my goal?”
- “How will my workout today help bridge the gap between A and B?”
My experience has been that simply for this and nothing else using a power meter has been invaluable. It is also pretty useful in helping with what will hopefully be the next question
- “Wow, that was fun, now I wonder what I can do next?”
I hope you find the same. Good luck.
What? No FTP?
It is rare for an article about power based training not to mention “FTP” and this is no exception. However, I have left it to after the end as I believe that used incorrectly, it can do more harm than good.
This is due to the existence of power profiles. Riders with the same zone 4 wattage (which is close to FTP) can have very different wattages for all the other zones. This is due to the underlying reality of how the body produces energy that was touched on earlier. Different individuals can produce the same watts number using very different means.
Naïve FTP does one simplified test and then calculates all zones based from this number. As a result, the zones will be wrong for most riders who are specialists at one zone or other, which is most riders. To make things even worse, there is no agreement about what form the test should take, both in terms of duration (8 minutes, 20 minutes, 60 minutes) and approach (with a preceding zone 5 effort or without? Ramp test or steady state?)
The reason for this situation arising is historical. When power meters were first introduced the software to make best use of them was not available so Andrew Coggan, who invented the term “FTP”, based his initial ideas on what was being done at the time with heart rate monitors.
This situation has now changed and several years ago Dr Coggan announced that he considered that FTP in its simple state was dead. He replaced it with a new concept which he called “mFTP”. While similar in name it is quite different in detail and, he would be the first to say, is only a part of the complex overall picture that explains a cyclist’s performance.
Word takes a while to get round. FTP is easy to calculate even if wrong and mFTP is only available if you use certain types of software. Some training tools, notably Sufferfest and Xert have dropped FTP but replaced it with quite different measures.
The situation is not helped by FTP taking on a life of its own as a target. Riders will compare FTPs (hand up I have done this) leading to the paradoxical situation that they will seek out the test (say 20 minutes) that gives them the best number and then train to improve it as a prime objective, despite the fact that the number of events that actually require you to go all out for 20 minutes are few (perhaps a 10 mile time trial, but you have to be pretty good and you would be unlikely to warm up with an all out Z5 effort for 5 minutes, unless you were late for the start) and those requiring you to ramp up from 100W until you crack are zero.
So, despite being wrong, FTP is still often used, including in packages like Zwift. My advice would be to use workouts from these sources with caution, not being afraid to create your own based on your real zones or change the target percentage if they feel wrong, since it is not you that is at fault.