Increasing the size of your bath tub.

By Hunter Allen

I am often asked many great questions.  One of the questions that I am asked often is,  “Which is better to improve your threshold power, riding longer rides or doing more intervals in shorter rides?”  The great thing about being a cycling coach is that most, if not all, your answers to questions such as this are always: “It depends”….  Seriously though, there are times when you should do longer rides in order to improve your stamina and other times when you should do shorter, harder intensity rides to improve your absolute threshold number.   How should you decide which you should do and when?   Let’s first examine a metaphor that I like to teach at many of my power seminars in order to teach  the importance of both types of rides and then dig deeper into the decision making process.

Let’s say for instance, that every cyclist has a “bathtub” of fitness.  In your bathtub, you have a drain, bathtub walls, a spigot, and some Hot and cold handles.  Some cyclists have a very big bathtub but with small walls.  These are the riders that can ride across the USA, with panniers and a tent, spending 12-14 hours rolling along at 14mph and seeing the sights over a summer.  They have incredible endurance, but at a slow pace.  They never “overflow” the walls of the bathtub because they just don’t ride at an intense enough pace to flood the massive floor of their bathtub. Then there are those that have two 50 gallon drums stacked on top of each other, tall walls but relatively small in volume.  These are the sprinters on the track.  Their bathtub can be “fire-hosed” for about a minute or two before it fills up and overflows onto the bathroom floor and since the drain is relatively small, they have to wait a while before they can “fire-hose” it again.  Then there are the road racers and stage racers; they have both a relatively large bathtub with tall walls.  These riders can handle a high flow of water into their bathtub and even some limited “fire hosing” as well.  Ultimately, that’s what most of us want, the largest volume bathtub with the tallest walls.  This would be the ultimate in the “bathtub” of fitness.  

Inside each bathtub, there is a drain that controls the flow of water out of the bathtub and the size of your “drain” is incredibly important to your ability to handle the water pouring into it.  The larger the drain, the more work you can handle as a cyclist.   In our metaphor, the drain is your aerobic efficiency, or how developed your cardiovascular system is within your body.  The more developed your aerobic system, the larger the drain and the more you train and longer you have trained the larger the drain.  Aerobic capacity and efficiency refers to the number of capillaries you have in your muscles, the number and size of the mitochondria in your cells, the stroke volume in your heart, the size of your heart and the maximized capacity of your lungs, along with many other factors. The bottom line is:  the bigger your “drain”, the more efficient you are at riding at a higher intensity for a longer time, which is endurance or stamina.    A road cyclist wants to first improve their drain and then begin working on improving the height of the walls in the bathtub. In order to do this, you must first “stress” the drain, by adding water pressure to it, which means you need to fill up the bathtub to at least three-fours full and once you have enough water pressure on the drain, then you need to maintain it for as long as you can by keeping the water or ‘dose of training/watts’ coming out of the spigot at the same rate as the water emptying out of the drain.  The body senses this “stress” and responds by increasing the size of the drain.   Any prolonged high-ish level of water in the bathtub, so to speak, will cause the drain size to increase.   From a training perspective, this means riding at an upper tempo pace (85-95% of FTP) will create enough water pressure on the drain to improve aerobic efficiency.  This is really the first step towards increased fitness and if you are working on increasing your overall FTP. Train your drain first.

In order to increase the height of the walls in the bathtub, then you need to stress the current height of the walls.  This is done by adding so much water to the bathtub that the water level goes over the edge and floods the floor of the bathroom or gets right up to the edge and threatens to flood.  This type of stress means riding right at your threshold power or “on the edge” and also just above it, so that the water is constantly at its maximum capacity of the bathtub.  The body responds to this type of stress, by increasing the height of the walls in order to prevent the water from escaping.  Of course, you can train at Level 4 or your functional threshold power before you “train the drain”, and increase the height of the walls, but then you will be left with a small drain in relation to the walls.   What this means in practical terms is that you will be able to ride at your threshold or slightly above for a 20-30minute period and not much longer and then need to wait for a while (30minutes or more) to allow the water to drain out, before having the ability to do another 20-30minute threshold interval.  If you haven’t figured it out yet, in our metaphor here, “water” is lactate in the blood.

Can you do both things at once?  Increase the height of your bathtub walls (FTP) and the size of your drain (aerobic efficiency/endurance)?   Of course!   One of the best ways to do this is by doing what I call the “Sweet Spot with Bursts” intervals.  These intervals are correctly done when you ride for 20minutes at your “Sweet Spot” (88-93% of FTP) and then every two minutes for the entire 20minute period, you do a hard burst of effort up to 120% of FTP for 30seconds and then recover back to sweet spot, but not lower.  This is like filling the bathtub about 3/4 ‘s full, then taking a fire hose and blasting water into the tub for 30seconds, just enough to get the water to the top and overflowing into the floor and then shutting off the fire hose.  Once the water drains back down to ¾’s full again, you “fire hose” it again!    By doing this, you increase the water pressure on the drain and at the same time you increase the height of the walls in the bathtub, hereby increasing both FTP and endurance.

Now, back to our original question of when should you work on which of the two components of the “Bathtub of Fitness”?    I will always say that you should increase the size of your drain first (endurance/aerobic efficiency) and then work on the height of the walls (FTP) second.  This is the general progression in periodization to begin with and it allows you to build a solid foundation of fitness, and increasing your FTP after you have established that initial level of fitness.   Once you are in the racing season or in the middle of the summer, then you might consider working on the height of the walls first.   As you probably know, your FTP and endurance increase and decrease in a wave like pattern through the season and if you are in the middle of the season and have just come off a long block of hard racing, you might best be served by continuing to work on the height of walls (FTP), instead of going back to increasing the size of the drain.  The key to doing this making sure that limit these intense workouts to only two a week.  If you do too much of the FTP work, then the size of the drain will begin to shrink and while you’ll have great form for criterium racing, you’ll be toast after an hour and half in a Road race. So, conversely, if you just have finished a week long criterium series with tons of FTP work, then I would suggest working on your endurance (drain) in order to prepare yourself for any longer rides.    Yet another scenario might be that you have a strong spring of racing and riding, and then decide to take a break for a month or two afterward, just riding casually and not doing any specific training.  In the late summer and early fall you decide you want to race in Cyclo-cross races and perform well.  In this case, I would work the “drain” first for at least 2-3weeks, and then do a week of intensity, working on FTP and then back to the drain for 2 more weeks and finishing with 2 weeks of working heavily on FTP (height of the walls).   When in doubt of which to do first, then fall back on working on your endurance/aerobic efficiency and then only when you feel you have done enough work improving the size of your drain, then move onto increasing the height of the walls or work done right at your FTP.  The “bathtub of fitness” is a key concept to understand for sustained and solid improvement season after season and year over year.  As you progress through your season, making sure you are working on the correct component is always essential to continued growth and hopefully now you have a better understanding of which part of the bathtub is the most important for you.

Plan your Peak for 2021.

We all have the best of intentions leading into the off-season and even after a non-season in 2020, it’s important to have that down time to recharge the battery.  That’s a critical part of making your 2021 season even better and if you come into next season with only a 90% charge in the battery you’ll never make that next leap in fitness.  One of the critical things that you must examine for next year is whether or not the training you did this year was effective.  If you made the improvements you wanted to make then it was definitely effective, but if you didn’t make those gains, you need to change something for 2021.  One of the easiest places to make a change is to plan out your peak and sketch out how you are going to get to that peak.   Planning for success is something that every winner does and if you don’t plan for success you are planning for failure.  How do you plan a season and what things do you take into consideration when training with a power meter?   While this column is too short to go into much detail, I would like you to consider five key factors in your planning for 2021.

Power Training Success Factor

#1-  Lock in your “A” priority events.  

Take time to look at this years’ race calendar and think about all the races or events you did and then which ones you want to do next year and which races are your top priorities.  I would suggest making sure that you pick not just one “A” priority event, but make sure there are plenty of races around that “A” race, so that you will be able to take advantage of your peak fitness.  I once had an athlete that was determined to win a particular race on June 9 and I did everything to put him on peak form for this race.   Unfortunately, he flatted in the first 5 miles of the race and couldn’t get back to the peloton, which was of course highly disappointing not to mention it ended up being a huge waste of the six months leading up to the race.  You see, there weren’t any other races within eight hours drive of his home for the next five weeks and he had the best form of his life, and nowhere but the “Tuesday night world championships” to use it.  So, I recommend you pick an event that suits your strengths and weaknesses well and also has other events close to that time frame in order to take advantage of your great form.  Once you have determined when you want your peak, you can begin to work backwards from there to establish the different macro cycles of training that you’ll be doing.  Macro cycles are the phases of training that you’ll focus on for a four to six weeks at a time in order to build a well-rounded level of fitness in which you can create a peak of form.  Using a power meter helps you to determine the optimal training load you can handle each week throughout your build and rest cycles.  I use Training Stress Score(TSS) in to establish those training loads and more accurately predict needed training loads each week, along with helping to determine length and intensity of rides.

Power Training Success Factor

#2-Know your strengths and weaknesses. 

Every six weeks you should be doing the “Power Profile” test, which tests your best efforts at 5 seconds, 1 minute, 5 minutes and 20 minutes. Each of these relate to different energy systems in the body, Neuromuscular Power, Anaerobic Capacity, Vo2 Max, and Functional Threshold Power(FTP), respectively and will change at different times and also in relation to each other.  When your fitness improves it is not necessarily true that your sprint will improve with your FTP, or that your Anaerobic Capacity will improve when your sprint does.   This makes it critical that you test them on a regular basis so you’ll be able to clearly understand which physiological energy system is changing and by how much.  Clearly understanding your strengths and weaknesses determines the type of training that you will be doing within each micro cycle(two to three week periods) and also will help you to determine if your weakness is a barrier to success.   For example, if your goal for 2021 is to ride well at the “Assault on Mt. Mitchell”, then you’ll need to be able climb very well and that means you’ll want the highest FTP you can achieve by race day and sprinting really might not be that important to your overall success. However, through your power profile testing you have learned that your sprint (5 second test) is the weakest of your energy systems and your FTP is the strongest (even though you always want it to improve).  Should you then spend all of your time training your sprint? No, that probably won’t help you to crush Mt. Mitchell and I would bet even if you trained your sprint 10 hours a week, you would not see much improvement as it tends to be more of a genetic limiter than one that can be improved through training. The bottom line is that you absolutely need to know for certain which are your true strengths and true weaknesses, and as long as you test these regularly, you’ll know when exactly these systems change after each training macro cycle and this will help to keep up on track for your peak along with making you aware of your racing tactical limitations.

Power Training Success Factor

#3 Understand your secondary limiters

– Along with understanding your gross strengths and weaknesses (whether or not I have a strong aerobic or anaerobic ability), you also need to understand how quickly you fatigue within these systems.  Some riders may have a tremendous initial ‘snap’ when they sprint, but fatigue quickly after a mere 100 meters of sprinting.   Other riders might not have an incredible ‘snap’ but are more ‘diesel engines’ when it comes to closing gaps, chasing down breakaways and hardly seem to fatigue at all no matter the time or distance.  The ability to ‘diesel’ means that you have more fatigue resistance than other riders and that fatigue resistance can be a part of each of your energy systems.  A sprinter like Mark Cavendish, who has an incredible snap, must win races by coming out of the draft with less than 100meters to go since he has poor fatigue resistance, whereas a sprinter like Peter Sagan needs to start his sprint from 250-300 meters out so he can take advantage of his strong fatigue resistance in the last 50m as others are fading. Mark Cavendish probably can do about 1800 watts for 5 seconds, but then only holds 1000 for 10 seconds and then at 20 seconds is down to 850 watts, whereas Sagan starts out with 1500watts, fatigues to 1300 watts by 10 seconds and still is cranking out 1100 watts at 20 seconds. This fatigue resistance that Sagan has will help him determine his sprint strategy and also the types of training he needs to do in order to improve his snap as well.  By using the Power Duration Curve in the TrainingPeaks WKO5 software, you can accurately understand how your watts reduce from 5 seconds to 10 seconds to 20 seconds.   Look at each “energy system range to understand if you have more fatigue resistance in one system over the other  (Vo2 over AC for example) This might mean you need to do some testing in these time ranges as well.  So for your sprint, you need to make sure you test your 5second, 10 second and 20 seconds and then for your Anaerobic Capacity, you should test your 30 seconds, 1 minute and 2 minutes.  As you test your fatigue resistance at Vo2 Max, you should test your 3minute, 5 minute and 8 minute ability and then finally you should consider your fatigue resistance at FTP, so that you test your 20 minute, 60 minute and 90 minute best efforts to clearly understand whether you are true ‘diesel’(strong fatigue resistance) or not(poor fatigue resistance).  How do you use this increased knowledge of your physiology?  By knowing your secondary limiters, you have another area to focus on in your training to help improve those limiters and give you more tactical racing options to use during your races.

Power Training Success Factor

#4 – Plan in your rest days and rest weeks

  Each week, you should have a rest day, where you either stay off the bike completely or just ride ‘embarassingly slow’.  This is absolutely a critical factor for success and so many riders just don’t do it.  Your body needs to recover, recharge and rebuild for the next day of hard training and a day of very easy riding or complete rest is really the only way to do it.  This is the easiest part of training and it’s an important one.  Many cyclists ride a little too hard on their easy days in order for them to be truly rest days, so when you do ride easy, go slow, and use your power meter as your governor.  Your power should be under 56% of your FTP about 90% of the time, but if you have to do 400 watts to get up a hill or fall over, then do the 400 watts, but maybe you’ll want to select a different route the next easy ride.  Throughout your plan for next year, you’ll also want to schedule in rest weeks and these allow you improve as it’s the rest weeks when your body gets stronger from all of the hard training you have been doing.   The great thing about planning in rest weeks and then sticking to them is that you force yourself to re-charge your battery no matter whether you feel like it or not.  Even though, you might not feel like you need a rest week, you can keep pushing through you could end up compromising your immune system or possibly compromising your next hard build cycle.  Scheduling in those rest weeks will control your overall training stress as well and prevent you from overtraining. How much rest do you need in a rest week?   I would suggest looking at your Training Stress Score chart so that you can see how many TSS points you accumulate during a normal week of training and then half that amount of TSS for your rest week.  If your normal week is between 700-800 TSS, then somewhere between 350-400 TSS for a rest week would be plenty and if you do less that would be fine as well.  

TSS chart by week highlighting a rest week.


Power Training Success Factor

#5- Build the Plan and do your best to stick to it.

While this seems relatively simple it’s much harder to actually create, implement and then keep to the plan throughout the season. Life does interfere and that’s one of the more challenging parts about cycling or any activity that you are committed to, and has to be worked around the rest of your life.   When you build a training plan, you always work backwards from the goal date and that begins to define your rest weeks, specific training weeks where you focus on your primary and secondary limiters and your “power foundation”.   Your power foundation is really the foundation of aerobic work that you lay down in order to be ready for the more specific work needed later.  This is not ‘base’ training, as that really is easy riding at endurance pace for hours on end and your power foundation is built on riding more intensely(tempo pace), and for shorter periods of time. In this day and age, we all have less and less time to train, and only the pros or Category 1 riders have time to ride an easy 5 hours every day for months on end and in reality, if we did that, our threshold power would likely decrease from lack of intensity.  What I like most about riding at tempo (76-90% of your FTP) is that it creates just enough stress on your aerobic system to maintain fitness and also is tough enough to keep those muscles engaged in pedaling hard on the bike.  This dual strain keeps your cardiovascular system primed for later work and also makes sure that you have the needed muscular endurance in order to do the longer rides on weekends and later in the year.  If you want to go to the next level, then you have to integrate in a long ride (4-6 hours) at least once and preferably twice a month to achieve the needed cardiovascular and muscular strain to improve. I have a “Next Level”  Training plan available here.    Your power foundation phase should last for a solid 8 weeks before starting with focusing on your primary and secondary limiters and I would recommend for most people this power foundation phase occurs from December to February depending on when you are planning on peaking. After this phase, you should make sure your plan begins to incorporate specific limiters even if you do just them once a week while continuing your work right at FTP.  As you get closer and closer to your peak fitness, you work to improve your shorter anaerobic efforts as your body will adapt much quicker to them than to your longer aerobic efforts.   One common mistake that many people make is that they ‘stack’ workouts when they miss them, so avoid this if you can.  If you miss the Tuesday workout, then don’t try and push everything back one day so you still get in the workouts.  It’s better for you to just move along to the Wednesday workout then worry too much about missing that Tuesday workout.  The only exception to this is when the Tuesday workout was addressing a key limiter to success and in that case, substitute the Tuesday workout for Wednesday and just forget about the Wednesday one. 

There are many factors that help you to success in cycling and books have been written about them. It’s my hope that this article will inspire you to take some time now and do these steps in order to plan for your success.  Make a plan.  Plan for success and use your power meter to help you stay on target.  If you don’t know you are improving or know your strengths and weaknesses then how will you improve?  How will you reach your goal no matter how large or how small. A carpenter does not just tell the guys one day to show up with a ton of wood and we’ll throw something together and then end up with a perfect house.  Each carpenter starts with a blueprint, a plan, a way to make sure they are building the house correctly.  Once that plan is established then every once in a while situations come along and you have to adapt to them, that’s normal, but you always come back to the master plan.  We plan for success in the rest of our lives, and we should do the same in cycling. Measure your results accurately, consistently and you’ll know when to make changes to your training plan so that you do achieve the best possible benefits a training plan can give you.

Hunter Allen is a USA Cycling Level 1 coach and former Professional Cyclist. He is the co-author of “Training and Racing with a Power Meter, co-developer of TrainingPeaks Software, and is the CEO and Founder of the Peaks Coaching Group.  2021 will be the 24th year that he has conducted training camps in the beautiful Blue Ridge Mountains.  Where did the time go?   We don’t know, but it’s time for you to come to a camp!

A Powerful Foundation of Fitness

I know you have spent a lot of time this winter on the indoor trainer doing workouts inside Zwift, Trainer Road, Rouvy and the rest of the “trainertainment” apps. These are great tools to increase your fitness in the winter, go to the next level and also to maintain your hard won fitness from last season. It’s always a battle in the winter with cross-training exercises, cold weather (for most of us!), indoor riding and just how much intensity to do indoors and outdoors on the good days. I prescribe a lot of tempo and “sweet-spot” work in the off-season in order to limit the upper intensities. If you ride at the higher levels in the winter, you risk peaking too soon and creating a lull in your fitness in March, right when most of the events begin in the US. To prevent this from happening, it is important to continue this building of your power foundation. 

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