Q&A: Measuring Aerobic Endurance Progress

I get questions from athletes daily. Unfortunately, I have to pay the bills (just like you, I expect) so can’t devote my time to answering them all. Consequently, our team of TrainingBible coaches and specialists (Dr. John Post – medicine, Cheryl Hart – sport psychology and Amy Kubal – nutrition) answer almost all of them for me. But from time to time a question comes along which gets at a topic I think lots of athletes may also be asking and so I answer some of them here. The following is one such question I just received from an athlete along with my answer.

Question: I have been spending 10-20 hours/week riding around in heart rate zone 2 for the last 4 weeks. I do 3-4 hour rides on the weekends and 1 hour work commutes twice daily during the week. I have to admit that it is trying my patience, but I have skeptical faith that this is better than riding as fast and long as I can. My challenge is two fold. I don't understand how to measure progress and I don't understand the theory. I have a heart rate monitor and GPS (Garmin Edge 500), but I don't have a power meter, therefore I can't perform the "coupling" measurement you describe in your book. As an alternative, could I measure my speed on a flat windless 2 mile course at a given heart rate and then expect that to increase? Perhaps I could even measure my speed at several heart rates (e.g. 135 bpm (zone 1) 145 bpm (zone 2), 155 bpm (zone 3), 165 bpm (zone 4)). Would that be a useful fitness metric?

Answer: I’m guessing this person is in his early Base period since he seems to be focused on zone 2. I have endurance athletes do lots of z2 early in Base as it helps build aerobic endurance, a very important component of the endurance athlete’s fitness. That’s one of the most important workouts I’ve had athletes do in Base 1 of classic periodization for years. It works well, but I also use block periodization for my advanced athletes and in that case usually make aerobic endurance the emphasis of Block 3 (I’ll write about block periodization at another time). There are some changes occurring in my approach to aerobic endurance training.

Based on some personal training and testing I’ve been doing since last December I’m coming to believe that z3 training is more effective for aerobic endurance training in advanced athletes (I’ll also write about the “N=1 research” I’ve been doing at a future time). So basically, what I have advanced athletes using block periodization do is a z3 workout followed the next day by a z2 and then by a z1/recovery day before starting the 3-day cycle over again. The z3 session on the bike is something such as 3-5 x 20 minutes in z3 with 5-minute recoveries in z2. The athlete’s purpose is to get as much combined z2-3 training within this session as possible with minimal z1 and z4+. The z2 day is just a steady workout with at least half of the time in z2. This block lasts for 3-4 weeks.

For all novice and intermediate athletes training fewer than about 9 hours per week and using classic periodization in the early Base period we get in at least two such z2 workouts each week (1 in each sport if a triathlete) along with speed skills and muscular force sessions. For triathletes, this is all explained in my new book, Your Best Triathlon.

The second part of this question has to do with how one knows if progress is being made in aerobic endurance – when as a cyclist he doesn’t have a power meter (same as no speed-distance device for a runner). The first suggestion I’d make is that he start saving his pennies so he can eventually buy a power meter. Look for someone selling a used one which will be much less expensive than a new one. Basically, without such an output measuring device you are always just guessing at improvement. A power meter removes the guesswork.

In the absence of a power meter, a very basic gauge of how you are doing with these aerobic endurance workouts is how long it takes you to ride a standard course in zone 2. Wind, traffic and other confounding factors will necessitate some guesswork. Another highly subjective gauge is how hard such a ride feels as you progress over several weeks. These are not very good predictors.

The best test I’d recommend is simply a CP30 test on a 3-5% grade hill when there is no wind and no intersections to stop at (be very careful when doing this test by keeping your head up at all times and watching for traffic). Ride (or run) as hard as you can for 30 minutes on this course – by yourself: No training partners and not in a race. Having others with you will screw up the results.

Be aware that athletes nearly always start too fast on this test and then fade badly later on. You’ll get the best result by starting slower and trying to get slightly faster every 5-10 minutes. Also be aware that you should be rested before the test. Take it easy for 2 days prior.

When aerobic endurance improves your CP30 also will improve. Why? Because to go hard for 30 minutes takes a lot of aerobically active muscle (read, “slow twitch” muscle). If your aerobic endurance has improved you’ll have more aerobically active muscle after 3-4 weeks of such z2-3 training than you had prior (when you should have done a pre-test).

Unfortunately, there is still some guesswork involved here if you don’t have a power meter. The biggest issue is weather – wind and heat, primarily. Was it the same the last time you did this test? A power meter eliminates that question as weather has no effect on power in such a test. In this case all you do is compare your pre-test power with your post-test power. If it improved then your aerobic endurance has improved.

I know of some coaches who use a 20-minute test similar to my CP30 test. The problem with this, I believe, is that there is too great of an anaerobic component which somewhat negates the aerobic component which is what we are trying to measure. It’s very hard to hold even a slightly anaerobic effort for 30 minutes when going it alone (you’ll ride or run a lot harder if in a race or with other athletes).

I hope this helps some although I suspect it will generate a lot of follow-up questions. I’ll get at this athlete’s other issue, aerobic endurance-related training theory, in my next post.

Comments

[Sam]

In regards to the benefits of Z3:
I spent 8 weeks focussing mostly on tempo during the worst time of winter--trainer mostly.
My first blood lactate test this spring showed a 20 watt increase in every zone, including OBLA. I was hoping to just maintain my fall levels, but I actually got better--without much intensity.

Keep in mind, I spent very little time in Z2 or Z4--mostly tempo and sub threshold (88-93%).

Working Z2--at this stage of my riding/racing--doesn't bring about much adaptation or measurable benefit.

[Pat]

Thanks Joe. Interesting post. Maybe I'm misreading what you've posted in the past or what I've read in the Training Bibles, but as I recall z3 was basically to be avoided. My impression is that z3 is unnecessarily strenuous compared to z2 (no additional training benefit), and would only serve to make the athlete too tired for subsequent workouts, whether z4 and above, or z2. I'd really like to hear more about these z2-z3 workouts and what's behind your decision to include them, especially if I'm right in thinking that you've said before to avoid z3.

[Joe Friel]

Pat--See comment above from Sam. He found exactly what I found with repeated testing. But probably not the same for all athletes. There are several "it depends" here. More on this at a later time.

[Joe Lip]

Joe, with the lack of a power meter, does it make sense when doing the CP30 test on a trainer that you could rely on gearing an cadence to measure improvement? I did the CP30 or LTHR test 3 times since November and noticed I was able to hold the same cadence during all three tests but was also able to spin a higher gear for each test. Would a method like this be reliable to judge improvement relative to past fitness? Thanks again!

[Joe Friel]

Joe Lip--THe big issue on a trainer is calibration of resistance. CompuTrainer allows for that so if that's what you use then it should be pretty good data. Of course, it also provides power data. With a non-calibratable trainer there's a big confounder.

[Madeleine]

Which end of zone 3 do you ask the athlete to target in the 3-5x20min pieces that you describe? As Allen & Coggan define it, Power Zone 3 is quite broad. 75-80%FTP feels very different from 85-90%FTP to me - I am one of those riders whose HR consistently resides one zone below the power zone.

Thanks,
Madeleine

[Rob]

Great article Joe! As a coach I also try to follow those basic guidelines for advanced and novice triathletes. For novice triathletes it's mostly about the endurance, build your base not just for today but for the longer term. Then, for more advanced triathletes or those that have that solid base, Z3 works great. Last year I did mostly all Z3 bike workouts and did not lose any speed in my races.
Thanks,
Rob

[Jim Wade]

Joe,

I assume the CP30 test is the LT test you describe on page 47 of your Total Heart Rate Training book.

If you are doing this test for running and have a GPS and HR devise what data provides information that is similar to a power meter?

[Shane]

Joe

For advanced athletes doing the endurance block periodization training, how do you incorporate speed skills workouts? Can it be part of the warm up for z3 or z2 days workouts? Thanks

[Roberto]

Hello Joe,

A very good post, as usual.
My contribution to the second part of the question: I've bought an eArticle from the site www.roadbikerider.com. It's titled Equations for Cyclists, in the second title you read "How to Calculate Intensity, Wattage and More – Without a Power Meter" the author is Coach Fred Matheny.
I've found the article pretty useful for those of us who can't afford a power meter yet.
Saludos desde Chile,

Roberto

[Joe Friel]

Shane--I devote block 1 to speed skills but it can be included at any time in any workout. Early in the season this is best done early in the workout--as a part of the warm up, usually. Later in the season do speed skills training late in workout.

[Joe Friel]

Jim Wade--For running speed/pace comes closest to power but, again, not nearly as precise due to hills, wind and surface.

[Joe Friel]

Madeleine--I leave it up to the athlete to decide based on how they feel. That always must be a consideration in any workout.

[Mike]

Thank you for addressing my questions.

You mention in The Cyclist Training Bible that zone 2 is the speed you travel in the peleton. Were you referring to heart rate zone 2 or power zone 2? For me heart rate zone 2 feels like what I would qualitatively call a "recovery ride". I average 12-14 mph over the whole ride. Heart rate zone 3 is only slightly more intense and is the speed I would qualitatively call "resting". When I ride in an unstructured manner I spend a majority of my time in heart rate zone 4 and a good chunk in heart rate zone 3. Is it possible that my heart rate is naturally a bit high and that I should adjust my zones upwards? Could I determine this if I had a power meter?

By the way, I am using heart rates based on my best guess measurement of my heart rate at lactate threshold of 171 bpm. I have based this off several 1 hour race pace training rides and 1 road race.

[Joe Friel]

Mike--I don't recall writing that but will take your word for it. Peloton could be traveling at any speed/zone, I suppose. HR and power zones don't necessarily agree, in fact, they seldom do although they usually overlap.

[Fulton]

Hi Joe,
I know that some coaches and athletes recommend doing micro-burst or micro intervals (15 seconds on - 15 off) for time trial training. the "on" portion is about 1.5 of FTP. what energy system(s) is suppose to train? i haven't found a study on it. However, Chris Boardman swore by it. I am gearing my training plan for 10 mile TTs.
Thank you,
Fulton

[Joe Friel]

Fulton--Yes, there are a few studies showing that. With short recoveries these are much the same metabolically as VO2max intervals that are longer (about 3 min).