The Aerobic Base Ride

A few weeks ago I suggested to Markus Zimmer, the owner of the Bicycle Ranch bike shop in Scottsdale, Ariz. where I shop that the store’s Saturday ride should include a “base” group in addition to it’s A-, B- and C-ability grouped rides. I usually ride with the Bs and occasionally with the As. This is only in the spring and fall. During the summer I am in Boulder, Colo. I’m also in Scottsdale during the winter but almost never ride with the group then because the A and B rides are basically mini-races. That’s great when I’m preparing to race. In the winter, however, my training purpose is not race fitness; it’s base fitness. You don’t establish base fitness by going deeply anaerobic repeatedly for a couple of hours.

Markus liked the idea and so last Saturday he offered a base group in addition to the three normal groups. There were probably 60 riders who showed up. Nearly all of them rode with the base group led by local coach Ron Arroyo. (I was injured and couldn’t ride. Fell on my knee a couple of weeks ago. That’s a whole other story I may get to at another time.)

My notion of a base ride is a long, steady workout with heart rate mostly in zone 2. This is roughly a well-conditioned athlete’s aerobic threshold. Riding two or more hours at this effort challenges the body to make some improvements. One is to become better at using fat for fuel while sparing muscle glycogen stores. The longer your races are, the more important this shift is. The other critical shift has to do with increasing the capillary bed in the working muscles. The more capillaries you have the easier it is to get fuel and oxygen to the muscle. There are other benefits also, but for now we’ll focus on these.

The problem with this base workout is that it seems too easy at first so the athlete is tempted to abandon the 2 zone and start riding variably paced with hard and easy efforts – fartlek intervals, essentially. And by so doing reduces the aerobic benefits of the day’s workout.

The aerobic threshold ride is sort of like Chinese water torture. What at first seems easily manageable eventually becomes challenging. One has to have the patience to hang in there to see what I mean. (This is one of the numerous reasons why I so often say that patience is necessary to be a good endurance athlete.) Ride for two, three, four hours at this effort and you soon learn what the aerobic system is all about.

Doing such a workout with a group presents problems, however. The greatest is that not everyone’s heart rate 2 zone produces the same power or speed. The highly fit, usually young riders are talking easily while riding in zone 2 – as they should be. The slower, usually older riders who try to keep up are often well out of zone 2 but determined to hang on. While this workout is best done alone, if in a group the best option is for the group to split up into smaller groups of like ability.

The best way to do this ride is to have a power meter onboard in addition to your heart rate monitor. While in the base period I like to have athletes use their heart rate monitors to set the effort, what happens to power is the real story. The best way to explain this is to use graphics.

Here you see two examples (click graphic to expand) of riders doing a steady, multi-hour, zone-2 ride. In both cases they are doing an excellent job of maintaining a steady heart rate as evidenced by the red line staying almost flat on both charts. But notice what happens to power (black line). In example 1 power closely parallels heart rate. That’s good. It says that the rider is staying “strong” throughout the ride. There is no fading of power (or slowing down, if you will, even though that’s not a very precise way to measure output on a bike). I call this separation of heart rate and power ‘decoupling.’ In fact, WKO+ software shows us that in example 1 there was only 1% of decoupling. In other words, power declined only 1% over the course of two hours of riding.

For the rider in example 2, however, the decoupling is 11%. He is fading significantly as the ride progresses. From these two examples I can tell you unequivocally that rider #1 is in much better aerobic condition than rider #2. If all they had were heart rate monitors we wouldn’t know this. Heart rate is only effective when we can compare it with something else. By itself it tells us nothing about aerobic fitness.

So does this mean that if you don’t have a power meter you shouldn’t do this workout? No, not at all. It’s still beneficial to your aerobic system. You just can’t measure your progress or know for certain when you’ve achieved good aerobic fitness. About all you can do in this case is to pay close attention to how you feel. If in good aerobic condition you should be able to finish the ride strongly, albeit tired. If you’re totally whipped after two hours and are struggling just to limp home although heart rate remains in the 2 zone, your aerobic fitness probably needs a lot of work.

Stress-Based Training

I've been traveling a lot this month including 10 days vacationing in the Caribbean. I'm now in Norway with some time to kill after speaking to a large group of athletes on Saturday. So I've been thinking a lot. The following is something which grew out of having a lot of uninterrupted thinking time.

Training for racing is all about adapting to stress. Pushing yourself to the limits of your abilities in a race is highly stressful. This stress comes in the form of some combination of intensity, duration and perhaps frequency. For example, the duration of a 20km cycling time trial is relatively brief, but the intensity is quite high. A 5km running race has a similar distribution of intensity and duration. Heart rate and perceived exertion are near their upper-end limits in both types of racing. In an Ironman triathlon, however, the duration is quite high while the intensity is quite low. That's another kind of stress. A cyclist competing in a stage race has a third variable with which to be concerned – frequency. This could take the form of two stages in a day or stages on consecutive days. The combination of intensity, duration and frequency is what makes events such as the Tour de France so challenging.

We can measure and quantify stress if we know duration and intensity (we’ll mostly ignore frequency for now). It’s easy for duration. Just use a stopwatch to determine how many minutes you exercised. Frequency is also simple. Count the number of races or workouts completed in a given number of days.

Intensity is more challenging. Endurance athletes are not very good when it comes to expressing how intense a race or workout was. The most basic way, the one athletes have been using for as long as there has been competition, is perceived exertion. “That was a hard race,” always means the same thing - intensity was high relative to the duration. In a similar way athletes typically use terms such as “easy” or “moderate” to describe intensity when compared with duration. But since this is al somewhat vague, ratings of perceived exertion (RPE) have been used to quantify the intensity-duration combination. The most popular systems were developed by Gunnar Borg. Here is his 10-point scale [1]:

RPE Zone - Level of Exertion
0 - NOTHING AT ALL
0.5 - VERY, VERY LIGHT
1 - VERY LIGHT
2 - FAIRLY LIGHT
3 - MODERATE
4 - SOMEWHAT HARD
5 - HARD
6
7 - VERY HARD
8
9
10 - VERY VERY HARD (MAXIMAL)

About 30 years ago the heart rate monitor was invented. By the late 1980s heart rate zones were being used to express intensity. For example, in the system I’ve been using for the last 20 years there are seven zones based on a percentage of your lactate threshold heart rate which can be found with a 30-minute time trial [2]:

HR Zone* - % Lactate Threshold
1 - less than 0.81
2 - 0.81-0.89
3 - 0.90-0.93
4 - 0.94-0.99
5 - 1.0-1.02
6 - 1.03-1.05
7 - more than 1.05
For the purpose of this discussion I've changed my normal normal zone titles for the anaerobic zones: 5a zone to "5," 5b to "6," and 5c to "7." You'll see why shortly.

For cycling, intensity may also be quantified with zones using a power meter in a way which is similar to heart rate zones. In this case the reference point is something called Functional Threshold Power (FTPw) which is very similar to lactate threshold. This also may be found with a 30-minute time trial. Then by using percentages of FTPw power zones are established that are unique to you.

Power Zone - % FTPw
1 - less than 0.56
2 - 0.56-0.75
3 - 0.76-0.90
4 - 0.91-1.05
5 - 1.06-1.20
6 - 1.21-1.50
7 - more than 1.50

Using the idea of FTP, running zones based on pace may also be determined. Only in this case “FTPa” stands for Functional Threshold Pace [4] and found by - you guessed it - a 30-minute time trial.

Pace Zone* - % FTPa
1 - greater than 1.29
2 - 1.29-1.14
3 - 1.15-1.06
4 - 1.05-1.01
5 - 1.00-0.97
6 - 0.98-0.90
7 - less than 0.90

Besides simply expressing intensity of a workout at any given time, these RPE, heart rate, power and pace intensity zones can be used to determine how long and how intense the key “breakthrough” workouts need to be to prepare you for stress of the competition. This is based on what the race will be like in terms of stress. Given some experience in racing you should be able to estimate what the stress of your race will be. For example, if you are doing a 90-minute, steady-state bike race that will be conducted entirely in zone 4 (using whichever system from above you prefer) then the stress of that race could be expressed as a "training stress score" (TSS) of 360 (90 x 4).

Now that you know the stress demand of the race the next step is to determine the key breakthrough workouts to prepare you for the race. In the early to mid-Base periods those workouts would involve low intensities, especially zone 2. So to do a 360 TSS workout in the first half of the Base period you could train for 180 minutes at zone 2 (180 x 2 = 360). This is a grea way to improve aerobic endurance.

By the late Base period you would be training with more zone 3 time so this would require 120 minutes (3 x 120 = 360). But by this stage it is wise to break the workout into intervals since this duration-intensity combination is becoming exceptionaly demanding. So if you did 165 minutes (2:45) including 5 x 20 minutes at zone 3 (300 TSS) with 4 x 5-minute recoveries in zone 1 (20 TSS), a 30-minute warm up with half in zone 1 and half in zone 2 (45 TSS), and a 15-minute cool down (15 TSS) you would again create a 360 TSS workout. Excellent muscular endurance trainng as you normaly should be doing at this time in the season.

In the Build period interval training would again be the way to go. And since we want the workouts to become increasingly like the race these intervals would be done in zone 4. A 367-TSS workout (a little over our 360 but not by much) may then look like this.

30-minute warm-up with half in z1 and half in z2 (45 TSS)
9 x 8-minute work intervals in z4 (288 TSS)
8 x 3-minute recovery intervals in z1 (24 TSS)
10-minute cool down (10 TSS)

You wouldn't want to do a workout like this too often. It's very hard. Probably no more than once every week or two would be best. This would depend on how stressful the workout must be to prepare you for the race and what your fitness is like at the time. Runners would also have to take into consideration the potential of injury from long and intense workout combinations.

This is a lot of work but it may be a way of getting you prepared for the stress of your race. You can do all of this or you can simply use WKO+ software (http://home.trainingpeaks.com/wko-desktop-software/analysis-software-for-training-files.aspx) with your power meter and/or accelerometer and GPS device. This software automatically determines a Training Stress Score (TSS) for each workout. You can also use this software to estimate the TSS of your races. This is what I do. Much simpler. And very effective.

References
1. Borg, GAV. Borg’s Rating of Perceived Exertion and Pain Scales. Champaign, IL: Human Kinetics, 1998.
2. Friel, J. The Cyclist’s Training Bible. Boulder, CO: VeloPress, 1996.
3. Allen, H. and A. Coggan. Training and Racing With a Power Meter. Boulder, CO: VeloPress, 2006.
4. Friel, J. The Triathlete’s Training Bible. Boulder, CO: VeloPress, 1998

Training Tools

In 1995 I tried using a power meter for the first time--an SRM the company loaned me for the summer while I was writing The Cyclist's Training Bible. It began to change the way I saw the process of training for bike racing and triathlon. Then in 1998 Tune, Inc. which created and sold the Power-Tap power meter gave me a prototype to use. I've been using them ever since and now require that everyone I coach also have a power meter. The heart rate monitor, while a useful tool in itself, is now an even a better tool. The combination of power and heart allows me to prescribe workouts and analyze their results in very precise ways. I don't know how I coached athletes before the power meter came along. I suppose it was all just guesswork although it seemed quite effective at the time.


Now something else has come down the pike that is once again modifying how I view and understand training -- WKO+ software (formerly known as Cycling Peaks). I started using it for myself and the athletes I coach last fall. Designed by Andy Coggan and Hunter Allen, this makes the power and heart rate tools even more effective. It took me a while to figure out, but once again I am beginning to see training in a slightly clearer way. Based on metrics called "Training Stress Score" (TSS) and "Intensity Factor" (IF) which are derived from power meter data, the software produces and updates daily how your training is going. (I won't go into the math of TSS, IF, etc here. Buy Coggan's and Allen's book, Training and Racing With a Power Meter for all the gory details.)

Let me give a small example of how my view of training is being refined and better defined because of WKO+.

Above is a screen shot of an athlete's "Performance Manager Chart" from WKO+. The red line represents fatigue, the blue line fitness and the black line form (race readiness). To paraphrase a basic concept from Andy Coggan, form = fitness - fatigue. This simply means that if you want to be race ready (rising black line) you need to first build fitness (rising blue line) by being very consistent with your training and then reduce fatigue (red) by allowing for rest. You can see this happening in the above chart. Fitness ratchets upward for several weeks as the athlete trains fairly consistently. Several times throughout this four-month snapshot fatigue is shed. You can see this as a drop in the red line. The athlete is resting by reducing training stress through less intensity, less frequency, less duration or some combination of these. As fatigue is reduced, form rises. The athlete is becoming race ready. Very simple to see.

But there are some less obvious nuances. For example, notice in circle "A" that fatigue drops and form rises. The athlete is becoming race ready. But also notice that fitness is dropping at the same time. Whenever training stress is reduced to eliminate fatigue, fitness also begins a slow decline. Basically, the same thing is happening with circle B--fatigue is down, form is up and fitness is dropping slightly. Even though form appears to be about the same level in both circles, notice that fitness drops more in circle A. In fact, the athlete reported not feeling very sharp at the form high point in A, but reported feeling quite strong at circle B's high form point. Obviously, because not as much fitness was lost.

So what does this mean? For years I have been tapering athletes in the Peak period by having them do a race effort workout every 72 hours with two active recovery days between. This has usually worked well. Circle B reflects that training method. Essentially, circle A had too many days of active recovery between the hard workouts. So because of the software now I can now see a representation of what I figured out many years ago and I can actually manage the day the athlete comes into high form. Pretty remarkable.

Stay tuned as I'm told there are even more remarkable features being designed for the software. It's becoming more fun all the time.