Power Pulse Intervals

Circuit Diagram for a Power Pulse Generator

In my junior year at the U of A, I took a circuits class with Dr. Miklos Silzaki or Shilzagi or Sizzleki or something. He was born in Budapest, Hungary and spent some time in Russia studying Electrical Engineering and Physics. He had some interesting (read: somewhat crazy) political views and described himself as a "liberal conservative" -- which may have simply meant that he was confused. We always found it strange when he would launch into some sort of political rant in the middle of a discussion about how capacitors work.

A nice guy, but a horrible instructor. I learned just about nothing from him and I was not alone. In fact, I recall reading a letter written to the Arizona Daily Wildcat back in 2002 regarding Miklos that expressed the same dissatisfaction with his teaching abilities as my friends and I had. I was even able to use the amazing power of the internets to find that letter, and the correct spelling of his last name, Szilagyi (pronounced just how it's spelled).

John Parker, at the time an Industrial Engineering senior said, "I believe that his method of teaching would be considered, if in some other profession, fraudulent, because it fails in the most basic objective of teaching which is to TEACH."

I still remember this funny thing about Dr. Siljocky -- dangit I already forgot how to spell his name. He would start class every time asking in his thick Hungarian/Russian accent, "Gude uff tanune, und vutt tis yore virsht kwesh tone?" (translation: Good afternoon, and what is your first question?). Since we weren't learning anything in his class we never had any questions. So instead we just stared back at him waiting for his standard reply, which was, "Ull rite, ten vutt tis yore seckund kwesh tone?"

Ahh yes, good times. I took that course with a friend named Billy who was extremely intelligent and never combed his hair (think Einstein). He was much smarter than I and a really fun guy to hang out with. We took a Design of Machines course together and teamed up on a project to design a mechanical bull using four-bar linkages and force, height, velocity, and acceleration requirements. It of course required on-site testing of the mechanical bull installed at the Wild Wild West nightclub on Ina.

Investigative Field Testing with Billy

We received an A on the project. Fun class, and Dr. Ara Arabyan was an excellent instructor. Billy, by the way, now works as a project manager in San Luis Obispo for REC Solar. I wonder if he combs his hair.

I know, I know... You see, I did an image search for "Power Pulse Intervals" so I could have a visual to share for this workout and the circuit diagram for a power pulse generator showed up, which reminded me of my circuits class... which reminded me of Miklos... which reminded me of Billy... which reminded me of the mechanical bull design.

Obviously, there are side effects from an SUV-induced-windshield-headbutt-to-asphalt-faceplant.

Power Pulse Intervals

Type:	Muscular Endurance
Duration:	30 - 60 minutes
Complexity:	2 / 5 (easy)
Difficulty:	4 / 5 (difficult)
Computer:	3-second power, heart rate, cadence, lap time

Power Pulse intervals are a Muscular Endurance (ME) workout. These intervals will help increase your ME by riding above lactate threshold and ending the interval shortly after you go anaerobic. The intent is to train your body to increase its aerobic duration by pushing the "ceiling" of your lactate threshold. If you find yourself getting dropped on the fast group rides, or have mediocre time trial results, or difficulty climbing at a strong pace for extended periods of time -- these intervals will help.

The Short Version

Warm-up
5 intervals of
- - CP12 power until HR is 3 bpm above LTHR
- - rest for 1/4 the work interval time
Cool-down

The Long Version

Determining your Interval Power

The first step for doing power pulse intervals is to determine what power output you should be achieving for the interval. If the power is too high, you'll go anaerobic too quickly -- too low, and you'll stay aerobic too long (perhaps forever). The right power depends on the individual, and is typically 5-15% above your FTP. You can try different values to find one that results in the desired interval duration, or you can use your Critical Power (CP) for 12 minutes (i.e. the maximum power you can produce for 12 minutes).

If you don't have a power meter, get one. If you haven't done testing to determine your CP12, do it. Simply warm-up and ride as hard as you can for 12 minutes, trying to maintain steady power output for the duration. If you don't know your FTP, do the CP30 test (but not on the same day as your CP12 test).

Some examples:

1. Adam did a CP12 test and was able to hold 275 watts for 12 minutes, so his interval power is 275 w.
2. Bruce did a CP30 test and was able to hold 250 watts for 30 minutes. He is too scared to do a CP12 test so he decided to just add 10% to his FTP (250 * 1.1 = 275 w).
3. Chuck just got a power meter but refuses to do any testing, so he decided to just try 400 watts and see what happened. He immediately went anaerobic but didn't know to stop the interval because he had no idea what his LTHR was. After two minutes he puked and everyone made fun of him.

Don't be Chuck.

After you complete your first interval, you'll have a good idea of whether your power output is appropriate for this workout. If you find that your first interval only lasts two minutes, reduce the power slightly for the next one. If your interval lasts 10 minutes, increase your power slightly. You're looking for around a five-minute interval.

Choosing your Route

Since you will be maintaining relatively high power output for relatively long periods of time, you will be covering a lot of ground. On a flat course at 275 watts a 6-foot tall, 150-lb rider would cover almost two miles in a single interval. You want to avoid routes that would have stops in it to disrupt your intervals. You also want to avoid rollers which will complicate maintaining a steady power output. The ideal route would be a hill climb with a grade of 2-5% and length sufficient to complete five full intervals. Mt. Lemmon is a great option. With a constant 5% slope, that same rider would now cover about one mile per interval. Five intervals fit very nicely into a ride to Molino Basin*.

* Every Thursday morning at 5:30 the JKG group meets at Le Buzz to ride to Molino Basin. Great group of guys, highly recommended.

Starting the Workout

Before you start, make sure you are sufficiently warmed-up and your computer is displaying power (3-second average), heart rate, cadence, and lap time. When you begin the first interval, press the lap button.

Ending an Interval

During the interval you will want to glance at your computer every so often to check your power output, heart rate, and cadence. You'll see your heart rate increase quickly over the first half of the interval and then slowly creep to your LTHR. Once you see your HR three beats above your LTHR, press your lap button and reduce power to zone 1 recovery. When you press your lap button, it should display the previous lap time. While you are recovering in zone 1, determine how long your recovery interval should be (1/4 the time of the work interval).

Remember to wait until your heart rate is 3 beats above your LTHR. You want to dip slightly into your anaerobic range to push your ceiling. Keep your power steady and avoid the temptation to push harder to increase your heart rate so you can end the interval.

So if your interval lap time was 5:36, your recovery time should be about 1.5 minutes (1 minute, 24 seconds if you're a math nerd). It doesn't have to be exact, but you don't want your recovery to be too long. I usually do 1 minute of recovery for intervals under 5 minutes and 1.5 minutes for intervals under 7 minutes. You won't be recovered completely, and that is by design. Your first interval will likely be longer than the others, and you may find that interval duration decreases with each interval. If your interval length drops below three minutes, decrease power slightly for the next one to try to stay in that 3-7 minute range.

Example of a Power Pulse Interval

The workout is complete once you have finished five intervals and their associated recoveries. If you pressed your lap button at all the appropriate spots, you should have 11 laps (one of them being your warm-up). After uploading your data you can take a look at each interval and make note of their duration and average power. With that information you can determine what power output you should shoot for next time.

For example, if your intervals were:

1. 300 watts for 3 minutes (1-minute recovery)
2. 270 watts for 5 minutes (1-minute recovery)
3. 280 watts for 3 minutes (1-minute recovery)
4. 240 watts for 6 minutes (1.5-minute recovery)
5. 250 watts for 5 minutes (1-minute recovery)

then you probably want to aim for 260 watts the next time. Ideally you want all five intervals to be 5 minutes long with 1-minute recoveries.

You'll probably want to limit this workout to once a week. After a month or two you'll notice your intervals will last longer -- to the point where you'll need to increase your power to keep them under seven minutes. Congratulations, this indicates an increase of your FTP -- which means it's time for you to perform another FTP test. You can try estimating your new FTP via this workout, but it will be slightly skewed since you are performing the workout on a hill climb -- it's better to perform a consistent test every few months.

Since this workout is based on heart rate, some additional influences (e.g. dehydration, lack of sleep, hot weather) will be a factor. Also remember to keep track of your fatigue with the Performance Management Chart ("Fitness & Freshness" in Strava) and avoid overtraining.

Resources

Most of the content you'll find on my blog comes from personal experience, but a lot of the advice I offer is based on information I've gleaned from books, magazines, and websites. I've created a page to list the resources that I've used over the years and highly recommend if you are looking to learn more about the sport. I receive no compensation for promoting these materials and welcome your suggestions for addition resources to add to my library. If you have a favorite training book, magazine, or blog that you'd like to share please feel free to leave a link in the comments section on that page. If you have your own blog that is cycling-related feel free to promote it there too.

To view the resources I currently have listed (including my thoughts on each book, magazine, and website) you'll find a menu link to the page in the upper right corner, or you can click here.

Tabata Intervals

Dr. Izumi Tabata

Type:	Anaerobic
Duration:	50 - 75 minutes
Complexity:	3 / 5 (average)
Difficulty:	5 / 5 (very difficult)
Computer:	3-second power, lap time, heart rate

Tabata Intervals are named after Dr. Izumi Tabata, who analyzed high-intensity training effectiveness when he was a training coach for a Japanese speed skating team. In 1996 he published his findings from a study where two groups of athletes were given different workout methods and their fitness gains were measured to determine which method worked best. The study showed that "moderate-intensity aerobic training that improves the maximal aerobic power does not change anaerobic capacity and that adequate high-intensity intermittent training may improve both anaerobic and aerobic energy supplying systems significantly, probably through imposing intensive stimuli on both systems."

In short, HIIT (high-intensity interval training) is good. And the Tabata Intervals described below are fantastic at increasing anaerobic power as well as aerobic fitness. Don't get me wrong though -- Tabata Intervals hurt -- they hurt bad -- but man, they are so good.

If you have trouble in crits due to repeated accelerations, Tabata Intervals are a great way to condition your body to provide you with the power needed for those short stong burts. The short rest portions of each interval help you learn how to deal with putting out a hard effort after an insufficient recovery time.

The Short Version

Warm-up
3 to 5 sets of (
 - 8 intervals of (
 - - - 20 seconds max, 10 seconds rest )
 - 4 minutes recovery )
Cool-down

The Long Version

You'll want a solid warm-up before starting the intervals. I usually warm-up for 20-30 minutes (which works out perfectly for the route I use for the intervals). My warm-up consists of 5 minutes easy riding in zone 1, then 5-10 minutes in heart rate zone 2. For these Tabata Intevals, I like to add 3 or 4 thirty-second "medium" efforts watching my heart rate climb to LTHR (lactate threshold heart rate), recovering between each effort to let my heart rate drop to my zone 2 level again. The idea is to reach LTHR right at the 30-second mark, ramping up steadily each time. After those efforts I then ride for another 5-10 minutes in heart rate zone 2. Note that the values in the graph below will likely not apply to you. It represents my personal LTHR of 174 bpm, maximim heart rate of 193 bpm, and resting heart rate of 38 bpm. Your values will probably be different.

My warm-up for Tabata Intervals

You will complete 3-5 sets of intervals, each set taking around 8 minutes. You will want a stretch of road with a slight uphill slope and no stops for at least 1.5 miles. You want a route that has very little traffic, especially if you will be turning around for each set. I've found that Freeman works well.

The set consists of 8 intervals and then 4 minutes of recovery. I find that the 4 minutes of recovery is just about enough time to turn around and descend in zone 1 to start the next set. Look for traffic and be careful when turning around -- timing is not important, if your recovery ends up taking 5 minutes beacuse you had to wait for cars don't worry about it.

The intervals are 20 seconds maximum power, then 10 seconds in power zone 1. If using a power meter, the output you want to generate is approximately equal to your best power effort for 1.5 minutes (consult your personal power curve). You may find, however,  that focusing on sustaining a specific power value during these intervals is difficult at best -- so just concentrate on putting out a solid effort for each set. You don't really need a power meter to do these intervals, but it is extremely helpful for post-ride analysis and it helps "keep you honest" during the 4 minutes of recovery.

Stay seated for the duration and keep your cadence around 90-100 rpm during the intervals and around 70-80 rpm when recovering. You will need to pay close attention to gear changes to make this fluid, especially if the route you've chosen has grade changes. Don't be surprised when you are unable to catch your breath during the 10 second rests. They are not meant to give you full recovery -- they are meant to teach your body how to repeatedly accelerate to maximum power. The graph below shows power, not heart rate (which will be high, and stay high). Note that the values in the graph below will likely not apply to you.

One set of Tabata Intervals

If, after completing 5 sets, you feel like you could do another one, you aren't pushing hard enough. The first time you do these intervals you may go too hard for the first 20 seconds and have nothing left by the time you reach the 8th interval. With experience you'll get a feel for how hard to push on each interval to be able to last the duration (but not a minute longer). After completing the final 4 minutes of power zone 1 recovery, you may find that you benefit from at least 5 minutes of a heart rate zone 2 cool-down. I usually just ride the remaining 20 minutes home in heart rate zone 2.

Watch what you eat/drink prior to and during this workout, unless you enjoy puking on the side of the road. If you do these Tabata Intervals, please feel free to post a link to your Strava or Garmin ride in the comments area below (or if you have any questions or suggestions).