Joe Friel's Blog, page 6

Midsole Cleats and Pedals

I’m occasionally asked if I still use midsole cleats when I ride instead of the traditional forefoot position. The answer is “yes.” I’ve been doing this since 2006 and it was the topic of one of my very first blogs back in 2007. Since then I’ve coached and spoken with other riders who have also made the change. Most found it beneficial but some decided it wasn’t for them. That’s pretty much the finding with anything unusual that’s tried by a large group of people. If you search “midsole cleats” on my blog you’ll find many of their comments and other pieces I’ve written on the topic.

Something I haven’t discussed here is the downside of making such a change. There are some rather minor ones, such as needing a completely new bike fit and the forefoot overlapping the front wheel making slow, U-turns a bit hazardous until one learns to adjust for that situation. The bike fitting is a given and should be done annually regardless of whether or not the cleat position is changed.

And it could also be that for riders who have many, many years of using the traditional cleat position that switching to midsole is likely to reduce their pedaling efficiency for several weeks. It’s also possible that the midsole cleat reduces absolute sprint power in road cyclists, although that’s not been tested in any research I can find. I’m convinced, however, that midsole positioning improves time trialing and climbing for roadies. For triathletes it seems a no-brainer as it reduces the work of the calf muscles, which do little more than stabilize the ankle, as the bigger muscles of the thighs actually produce the torque. Since the calf is minimally worked with the midsole position, the triathlete starts the run with much fresher calf muscles, the primary movement muscles for running. Seems like a pretty good thing to me.

The big downside I haven’t discussed much here is getting shoes and pedals that work well for the midsole position. As for shoes, the athlete who decides to make the change must either modify a pair of shoes (best to start with an old pair) or buy new custom-made shoes. I’ve done both. I started with redrilling a pair of Shimano shoes I’d had for a couple of years. Since then I’ve been using custom shoes from D2 Shoe. I’m on my third pair. They’re very nice, but more expensive than buying over-the-counter cycling shoes. (You can see a picture of my most recent pair on my blog home page.) 

There’s another downside that is usually the one that stops riders from switching over to the midsole position—changing pedals. You more than likely won’t be able to use the pedal system you currently have. That’s because the midsole or arch area of the cycling shoe is typically quite narrow. A four- or three-bolt cleat simply won’t fit there. It’s too wide. That means you have to go to a two-bolt cleat, typically called a mountain bike pedal system. That will fit and most work just fine in the narrow space of the shoe’s arch area.

A “pure” mountain bike pedal won’t really work as there is not medial-lateral support on a road shoe to stop the foot from tilting left and right while pedaling as is built into a mountain bike shoe. That limits your options. Here are the pedal systems I’ve used over the years, in the order in which I used them, and what I learned about each.

Shimano SPD A520. I used this one for many years. At about $55 it’s cheap, fully adjustable for release tension and designed for a road shoe. But it’s relatively heavy. They also wear out rather quickly. I would typically get nine months from a pair before they started squeaking telling me they were close to dying. You can’t repack the bearings so they are just throwaways.

Crank Brothers Eggbeaters. These are lightweight, minimalist pedals that come in a wide range of prices. The float and exit tension are not adjustable, but I didn’t find this to be a problem. The only thing I didn’t like about them was that I had to repack grease frequently as they would start squeaking. They would also squeak a bit if I got dirt on the cleat.

Sampson Fondo. This has a very similar look to the Shimano A520, uses exactly the same cleat and the release tension is also adjustable. As pedals go, it’s still cheap at about $100. It’s a bit lighter than the A520 and they seem to last longer. I had a pair I used for more than a year that I never wore out before switching to the next pedals.

Bebop. This is what I’m currently using. I’ve been on them for four months and so far I really like them. They are very light, depending on the model you select (I’m using the titanium model) and come in a wide range of prices. As with most everything in cycling, as the weight goes down, the price goes up. It took a lot of rides to become comfortable with clipping in. Unclipping is no problem at all. Release tension is not adjustable, but I’ve had no problems with that even when sprinting. They’ve never released prematurely. My only concern has been the liberal amount of float. At first I felt like I was pedaling on wet ice. Although I’ve learned to control my sloppy foot movement, I’d prefer less float.

This is not an all-inclusive list of the two-bolt pedal systems that will work with a midsole cleat position for road riding. It’s only a few of them. I’d be interested in hearing from you if you’re a midsole-cleat rider and what you’ve learned about the pedals you’ve tried. Please feel free to leave a comment.

The Efficiency Factor in Running

High performance runners are typically very efficient. One can observe this just by watching them run: there is no apparent wasted energy. They look very graceful. Their efficiency can actually be determined in a physiology lab by measuring how much oxygen they use to produce a given submaximal running speed. Oxygen consumption is a good indicator of how much stored energy, in the form of fat and carbohydrate, was used to produce that run speed. As oxygen consumption rises, more energy is being burned. A middle-of-the-pack, age group runner will typically require much more energy to produce the same speed. So the age grouper is less efficient—and that could also be demonstrated in the lab.

Efficiency is therefore a very good way of gauging how fit a runner is, especially aerobic fitness. The problem is that measuring efficiency in a lab is not only inconvenient, it’s also expensive. Well, there happens to be another way of measuring efficiency that doesn’t require a lab and can be done with common, everyday training technology. On the TrainingPeaks website it’s called the Efficiency Factor (EF). By measuring your EF for submaximal, aerobic runs you can gauge your fitness on a daily basis and compare trends over time. If your EF is improving then you are becoming more efficient and therefore more aerobically fit. TrainingPeaks automatically does this analysis for you after a run is posted.

All it takes is a speed-and-distance device—a runner’s GPS—and a heart rate monitor. The GPS device tells you how fast you were running—your performance. And, of course, the monitor reports what your average heart rate was for the run. While heart rate doesn’t tell us anything about performance, it is a good indicator of effort. Effort is just another way of saying the cost of the run. Knowing both performance and cost we essentially know your efficiency for a run. So with these two devices, and with TrainingPeaks as a post-workout analysis tool, you have your own “lab.”

So how is it that heart rate is an indicator of cost? We know that as the speed of your run increases, more energy is required and your heart rate rises accordingly to supply oxygen to the working muscles in order to produce the energy. The energy you burn and heart rate during a run therefore follow the same trend. When the energy required to run increases, heart rate also increases. As you become more efficient (we call this “fitness”) the energy cost of running decreases along with a decreased heart rate.

TrainingPeaks calculates EF by dividing your speed of running by the heart rate required to produce that speed. If the run was done on a flat course or a track this is a pretty simple process. But if there were hills, the changes in speed must be taken into consideration. That brings us to something TrainingPeaks calls Normalized Graded Pace (NGP). The GPS knows when you are on a hill, either going up or down. It also knows how steep the hill is. Therefore it can calculate what your speed would have been had you instead been running on flat terrain. That adjustment is the NGP for your run. It will typically show up in the post-run analysis as being faster than your average pace for the run.

Following the workout, and once data is uploaded, TrainingPeaks knows both your NGP and average heart rate. It converts NGP to a Normalized Graded Speed (NGS—yards or meters per minute) and then divides that result by average heart rate. That produces EF.

Here’s an example to show you what’s going on inside of TrainingPeaks after you’ve uploaded a run workout in which the NGP was an average 7 minutes and 30 seconds per mile and the average heart rate was 150.

NGP = 7.5 min per mile

NGS = 60 ÷ 7.5

NGS = 8 mph

Yards/Minute = 234.7 (1760 yards x 8 ÷ 60)

Avg HR = 150

EF = 234.7 ÷ 150

EF = 1.56

Whew! That’s a lot of math. Good thing that the software does all of that for you.

Now by comparing the EF for similar workouts over time you can gauge how your aerobic fitness is changing. As the EF rises, aerobic fitness is improving. As it falls, aerobic fitness is decreasing. Of course, the workouts you’re comparing should be similar, meaning the course and terrain were about the same as well as the weather, your effort and a number of other elements that typically affect heart rate such as caffeine, lifestyle stress, altitude and more.

EF can also be used to measure portions of a workout, such as intervals or a long, steady hill you run up frequently. All you have to do on TrainingPeaks is use your mouse to highlight the section of the run you want data on and there is your EF along with the other details for that segment.

One of the best workouts for applying the EF concept is a workout I call the aerobic threshold (AeT) run. Warm-up and then run for a standard duration, such as 30 minutes, on a standard course while keeping your heart rate 28 to 32 bpm below your lactate/anaerobic threshold heart rate. This is roughly your aerobic threshold. By recording your EF for that workout portion and repeating this workout frequently you will be able to determine your aerobic fitness progress.

Paying close attention to your EF over the course of several weeks is an easy way to measure your fitness improvement with field tests. It’s also much less expensive than going to a physiology lab every time you want to know.

Polarized Training Update

In December last year I posted here a review of some of the research about a way of training that scientists call “polarized.” That’s just a catchy way of saying do workouts with an intensity that is either high or low while avoiding moderate efforts. So train mostly at opposite ends of the intensity spectrum. There is another, more recent study, the best one done so far, which adds greater credibility to this concept. Before getting into that, however, let’s review what high, low and moderate intensities mean.

Intensity

Polarized training studies always define “high” as any intensity above the anaerobic threshold (AnT). This is similar to the lactate threshold with which you may be familiar. On a perceived exertion scale of 1 (low) to 10 (high), anaerobic or lactate threshold is about a 7. If you use my heart rate zone system, that’s the start of zone 5a. When using a power meter with Coggan’s method, anaerobic threshold might be defined as occurring at about your Functional Threshold Power (FTP). If you’re familiar with the concept of FTP you then understand that an AnT effort could be maintained for about an hour.

“Low” intensity in polarized training is below your aerobic threshold (AeT). This level of intensity is best determined in a lab during an anaerobic or lactate threshold test. It’s the intensity at which breathing and muscular effort increase only slightly but noticeably above resting levels. If you know your lactate threshold heart rate, AeT is roughly 30bpm lower. You could maintain this effort for several hours. AeT is roughly the intensity used by age group athletes in very long events such as an Ironman triathlon or an ultraendurance running or cycling race. In other words, low intensity are efforts easier than AeT. They are very easy—what you should normally use during a recovery workout.

As you might have reckoned by now, the “moderate” intensity in polarized training is the training done between AeT and AnT. So with my heart rate zone system this is zones 2, 3 and 4. With Coggan’s power zone system that’s everything from zone 2 up to FTP.

Research Subjects

Back to the most recent study on the topic of polarized training…

The study mentioned above is a good one to examine as it had a relatively large number of subjects (48) who altogether participated in four sports—running, cycling, triathlon and Nordic skiing. It’s also a good one because the subjects trained for a relatively long time—9 weeks. But as with all studies, the key to its applicability to you is knowing who the subjects were. They were all experienced athletes with an average aerobic capacity (VO2max) of 62.6. That’s generally not “world class,” but perhaps “national class.” It’s high and certainly at the upper end for most age group athletes. Their average age of the study's subjects was 31 and average weight was 162 pounds (73.8kg) with an average height of 71 inches (180cm). They had previously trained at least six times a week in their sports for a minimum of 10 hours per week and had competed for at least 8 years. I’m giving you all of these details because if you aren’t roughly of a similar background then the results of this study may not apply to you.

Study Design

The 48 athletes were divided into four groups based on the training protocol they would each follow for the next 9 weeks.

HVT Group. This group trained with high volume meaning that the emphasis was on total hours of training weekly with nearly all of it in the low intensity zone (below AeT). But each week they did one session of an hour with intervals at about AnT (such as 5 x 7 minutes with 2-minute recoveries and 3 x 15 minutes with 3-minute recoveries). Every third week they included seven days of recovery with alternating low-intensity endurance sessions and days off. This training protocol is similar to what most of us do in our early Base periods.

THR Group. The focus of this group was training at AnT. They also trained in three-week blocks with two weeks of high volume including four interval sessions at AnT (such as 5 x 6 minutes, 6 x 7 minutes and 6 x 8 minutes each with 2-minute recoveries) followed by a recovery week. In the two hard weeks of each block they also did a weekly AnT session with longer intervals (3 x 15 minutes and 3 x 20 minutes with 3-minute recoveries). This way of training is similar to what many athletes do in their late Base or Build periods.

HIIT Group. This group placed an emphasis on training above their AnT but also followed a three-week periodization pattern. During 16 days in each three-week block they did 12 interval sessions above AnT (such as 4 x 4 minutes with 3-minute recoveries) with a day off every fourth day. Their recovery weeks were done at low intensity alternating with days off. This type training is what a few athletes do in their Build periods, although it certainly involved more interval sessions than most would do.

POL Group. This is the polarized group. They trained with a combination of the HVT and HIIT groups—either very hard of very easy. Also training in three-week blocks, they did two weeks with two HIIT interval sessions each week and with four long sessions done below AeT. Every third week (recovery week) they alternated days off with a single HIIT session and long workouts done below AeT. Their training was unique in that they never did any training between AeT and AnT. Few, if any, athletes train this way.

Results

So what did the researchers find out when they tested the athletes after the 9 weeks of training and compared the results with their pre-tests? The group of subjects who showed the greatest physiological and performance benefits were in the POL group. Their VO2max increased, on average, 11.7%. Their time to exhaustion on a ramp test increased 17.4%. Peak velocity (running or skiing) and peak power (cycling) improved 5.1%. Velocity and power at AnT improved 8.1% even though they never trained at AnT. All of these were significant, positive changes. The HIIT group improved the last metric by 5.6%, time to exhaustion by 8.8%, peak velocity/power by 4.4% and VO2max by 4.8%. The THR athletes slightly improved their work economies (how much energy they used) at AnT but otherwise had no significant changes in physiology or performance. The HVT group experienced no significant improvements, which might be expected from a group of serious, high-performance athletes who normally train with frequent high-intensity sessions. This last group was, essentially, undertraining.

Conclusions

Again, the subjects in this study may be the key to determining if you should train with a polarized method. Even though HVT (the high volume, low intensity group) had no improvement, a novice (year 1 in their sport) or intermediate (years 2 and 3) athlete may find just the opposite—great improvement in physiology and performance by training with high volume and low intensity. In fact, training as the POL or, especially, the HIIT groups did may soon result in injury or overtraining. These methods are best used by advanced athletes (greater than 3 years in the sport). The more experienced the better.

Intermediate and the less experienced of the advanced athletes may make great gains by training with the THR group’s method—lots of time at about AnT. This way is somewhat similar to what Coggan proposes with his “sweetspot” training methodology with 2 x 20-minute intervals at 88-93% of FTP with 5-minute recoveries. I’ve seen a lot of athletes improve by training that way.

Of course, all of this raises the issue of periodization. It’s not a good idea to train the same way, week after week for an entire season. Not only does the risk of burnout increase, but there is likely to be a plateauing of gains in a matter of a few weeks which can’t be overcome by continuing with the same training method. Change is beneficial in these regards.

The underlying philosophy of periodization that I continue to drive home here is that workouts should become increasingly like the event for which you are training over time. This includes both intensity and duration. For stage racers it also includes the frequency of hard workouts. The general periodization model I use has the Build period (“specific preparation”—the last 12 weeks or so before an A-priority race) increasingly mimicking the stress expected in the race. So you have to decide how long the race will be and what the expected intensities will be and then design workouts that gradually produce some racelike combination of those stressors.

But in the Base period (“general preparation”—the weeks prior to Build) the workouts are not necessarily like the race. So this is the time, for example, to emphasize strength training in the weight room. This is “general” training since you never have to lift weights during an endurance event such as a bike race or triathlon. In the same way, if your event calls for racing in the “moderate” intensity range (between AeT and AnT) then doing the HIIT-type of intervals in the late Base period may be a good idea as it is likely to boost your fitness significantly. This could lift your Build period, race-specific training to a higher level. So for a long-course triathlete or marathon runner the time for polarized training may well be in the late Base period—the last few weeks before starting the Build period.

On the other hand, road cyclists may find that the best time for polarized workouts is in the Build period since the outcomes of these types of races are usually determined by brief, intense efforts done well above AnT. So a cyclist doing road races or criteriums may well do lots of very high intensity intervals and sprints along with climbs above AnT in the last few weeks prior to an A-priority race.

The bottom line here is that even though polarized training has repeatedly been shown to produce the greatest improvements, how you train throughout the year must be seen in a far broader perspective. Smart training is not an either-or proposition. You don’t just train one way or the other throughout the entire season. It always comes down to taking a long-term view relative to your races, goals and personal limiters and then designing a training program that addresses these matters. In other words, smart training is generally a rather complex and laborious task. This is not to say that it can’t mastered by amateur athletes. I come across many such people all the time. But if you aren’t interested in becoming a student of sport science then you may be better off hiring a coach or perhaps finding a generic training plan that guides you through your race preparation.

Rest and Recovery

Almost four months. I believe that's the longest time I've ever gone without posting to my blog in more than six years. Several readers have emailed asking if everything is ok. I really appreciate their concern. Yes, everything is going well. I've just been unbelievably busy, especially with travel around the world and speaking engagements. But I'm trying to get back to posting more frequently, if not in depth on a topic (there are several such things I would like to eventually tell you about but they will have to wait until thngs slow down a bit). But I get occasional interesting questions from athletes and coaches which I answer individually, but think it may be good to post them here somtimes, also. I received the following one today that gets at a crucial aspect of training which athletes can sometimes not fully understand. Here's the question and my answer (the writer's name is omitted since I don't have permission to use it).

Question:

Hi Joe,

I have a 16-year-old that is competing at national level in cycling in the UK. He is a junior rider next season and will be competing in national road races of 100-120km. He is about to embark on a period of rest and recovery. His training volume has been typically 10hrs per week. He weighs 52kilos and has a threshold of around 270 watts (1hr).

A three week rest period seems typical (from blogs and word of mouth). I have no doubt he will be climbing the walls after this period! It seems like an incredibly long period to stay off the bike. Would 2 weeks be insufficient? If so, why. Do you agree with a period of 3 weeks for young athletes? Is it more important for young athletes over older athletes to take this kind of rest?

Regards

JH

Answer:

Hi JH,

Thanks for your note. Good question. Rest and recovery doesn’t necessarily mean time off the bike, although some of that is ok. For most athletes it means "active" R&R which involves riding short durations at low intensity (usually zone 1). There are 3 times when R&R is common for a young rider: weekly, monthly and annually. Weekly is roughly about every other day (but perhaps slightly less often sometimes as when preparing for a stage race or in the base period when training sessions may not be as stressful). This weekly recovery is incomplete so fatigue still continues to accumulate but it is kept under control. Monthly R&R is usually 3-5 consecutive days after about 3 weeks of hard training. This allows for more extensive recovery--yet still incomplete--and prevents overtraining. At the end of the season R&R lasts 1-4 weeks and produces complete recovery which often means eliminating niggling injuries and psychological burnout from being focused for so many months on race preparation. For older athletes (35+) there is usually more frequent R&R which also may last longer. I hope this helps, but let me know if not.



Joe Friel

High-Intensity Interval Duration

I've finally got the manuscript written for the book on aging athletes I've mentioned here several times. The working title is "Fast After 50," and it will probably be ready by the end of the year - in both English and German. The weight of the world is off of my shoulders and I'm getting back to a normal life which includes posting to this blog. Another big project is looming and so I've been reading a lot of training-related research recently. That's how the following post came about.

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One of the best workouts for building fitness is intervals. That’s a session with alternating hard and easy segments. I previously wrote a series of five posts describing the details of interval training (part 1, part 2, part 3, part 4, part 5). Early in that series I explained that the word “interval” actually refers to the easy segments, but most of us use the term to mean the hard parts. So to hold down the confusion in this update on the topic I’ll refer to the hard segments as “Work Intervals” (WI) and the easy portions as “Rest Intervals” (RI).

When doing intervals, or any workout, the key question must always be: What is the purpose of this session? If you can’t answer that question with something other than a vague to improve my fitness, then the workout may not be appropriate. You could be doing something that has little merit in terms of the race or event for which you are training. For example, a marathon runner gets little or no race-specific benefit from doing sprint power intervals. A win is unlikely to come down to an eight-second, all-out sprint at the line. But for a road cyclist such a workout may be perfect.

The second most basic question has to do with timing: Is this the best time in my season to do this workout? Something I often mention in this blog is that the purpose of periodization is to improve performance for a given event on a given date. I also frequently point out the way to periodize training is to have the workouts become progressively more like the event in the last few weeks prior to that date. Doing the opposite – making the workouts less like the event as you approach race day – only results in poor to mediocre performance. Increasing race specificity in training is one of the keys to good planning.

In this post I want to look only at interval duration, primarily for the length of the Work Interval (WI) in an anaerobic endurance interval workout. The physiological reason for doing this type of high-intensity session is to improve aerobic capacity (VO2max). Athletes in a wide range of endurance sports do anaerobic endurance intervals at some points in their seasons. For endurance events that are raced at high intensity (for example, bicycle road races and criteriums, 3- to 5-km running races, short mountain bike races, 100- to 1500-m swim races, sprint triathlons) anaerobic endurance intervals are commonly done in the Build period (the last 8 weeks or so prior to tapering/peaking). For events done at a low to moderate intensity (for example, running marathons, mountain bike marathons, half Iron and Ironman triathlons, very long bike time trials) such high-intensity intervals are perhaps best done in the latter portion of the Base period some 12 to 18 weeks prior to the A-priority race. For those events between the two categories – such as those raced at near the lactate threshold - the timing of anaerobic endurance intervals is much more open to debate. (I’m being a bit vague on this because when it comes to periodization there are a lot of “it depends,” such as age, ability, experience in the sport, capacity for work, susceptibility to injury and many others).

With all of these details out of the way, let’s get back to the purpose of this article: How long should you make the WI in a high-intensity, anaerobic endurance interval session with the purpose of improving aerobic capacity and, therefore, race performance? It just so happens that a recent research study out of Lillehammer University in Norway took a look at that question. (This team of sport scientists has recently produced some excellent studies that can be directly applied to training in the real world. I intend to feature more of their research in future posts.)

The Norwegian researchers compared short and long intervals to see if there is any benefit one way or the other when it comes to aerobic capacity and performance benefits. They divided a group of 16 competitive cyclists into two groups with both doing anaerobic endurance intervals at the same intensity - about 90 to 100% of VO2max - with WI being the main difference. For 10 weeks they did either short or long WI workouts twice weekly.

The short intervals (SI) group did 3 sets of 13 x 30 seconds with 15-second rest intervals after each WI and 3 minutes of extended recovery between each of the 3 sets. The long intervals (LI) group did 4 x 5-minute WI with 2.5-minute RI. The recoveries for both groups were active, meaning they continued to pedal at a low intensity. The combined high-intensity time of the interval sessions were similar between the two groups. The SI workout resulted in 19.5 minutes of total hard effort while the LI group did about the same with 20 minutes of high intensity per session.

These are extremely hard workouts. A cyclist can typically sustain 100% of VO2max for about 5 minutes. Doing it 4 times in a session with only 2.5 minutes to recover after each as LI did is a lot of suffering, especially when you consider that this was done 20 times in 10 weeks. But 13 x 30 seconds with a paltry 15 seconds to recover in each of the 3 sets was no walk in the park for SI either. These were both certainly sufferfests. Perhaps the only saving grace from the riders’ perspective was that the WI were done at 88 to 100% of max heart rate. Since heart rate tends to drift upwards during such a session and come down more slowly with each succeeding RI, it would become somewhat easier to achieve the goal intensity on each subsequent WI. Easier but by no means easy. Cycling power is a better way of gauging the intensity of interval workouts as it stays constant throughout. There is no power drift meaning each WI from beginning to end would be of the same quality. And, in fact, power was measured during each interval for both groups. The LI group produced a slightly lower average power due to the length and sustainability of their longer WI. (The closest equivalent to power for runners is pace.)

The results of the groups’ training were interesting. The LI group improved their VO2max by 2.6% on average over the course of the 10 weeks, but the SI riders had a huge average improvement of 8.7%. SI also made greater performance gains in 30-second, 5-minute and 40-minute time trials.

Other studies of long versus short WI in well-trained athletes have found little difference in the physiological benefits. This study is unique, however, in that the total intervention period—10 weeks—was much greater than in previous such studies. The relatively short RI were also unique. At a duration of 50% of the WI they were shorter than is commonly done. This meant that the athletes’ stress throughout each interval session was at or near VO2max for a longer total time than is common with a longer RI. With long RI the density of the stress is reduced thus somewhat lessening the benefit.

This last point probably also explains why the SI athletes improved to a much greater amount than the LI. With only 15 seconds to recover after each WI they never even came close to full recovery for 6 minutes in a set. The LI group, however, would have experienced slightly less total continuous stress per session due to the longer RI.

The researchers point out that such high-intensity interval sessions are better for performance the more highly trained the athlete is. This, again, may explain why the very brief WI of the SI group produced results that were so much better than was found in other studies with relatively long RI. The subjects in this study were highly fit with average VO2max values in the high 60s. Subjects in previous studies of interval duration were much less well-conditioned. What this means is that if you are not at or near a very high absolute level of performance (not merely at an elite level in your age group) as indicated by a high VO2max, then using very short RI after also short WI may not be the best way for you to do intervals. In this case, a 1:1 ratio of WI to RI may be better for you. That would be something like a 30-second WI followed by a 30-second RI.

If you have not previously done high-intensity interval sessions in training or if there has a been a break of several weeks since you last did them, it’s probably best to start at a much lower level of total interval time in a session than was used in this study. That could be something such as one set of 10 x 30 seconds with 30-second recoveries or 5 x 1 minute with 1-minute recoveries. But if you are an elite athlete (meaning you’re a contender for the overall podium positions in races) and have been doing high-intensity training recently, then the SI type of workout described above may be a good training option when the time is right to build aerobic capacity.

Common But Confusing Training Terms

Recently reader Kevin Wellenius asked if I would define some sports science terms that pop up from time to time in books, magazines and on websites. I thought that was a great idea as I frequently am asked about each of the terms in his list below. It’ll make my life a bit easier if I can just point someone at this blog rather than explain again and again. Not that I’m lazy… Below are Kevin’s terms and my definitions. I added one to his list - FTP.

Note that not everyone in the field of sport science will agree with me on each of these. Scientists can - and do - argue about how many angels can dance on the head of a pin. There’s nothing wrong with that, I guess, so long as you have the time. And it's quite understandable as precision is quite important in the scientist’s lab. When exercise moves from the lab to the real world, precision is nearly always compromised. In the lab almost everything is tightly controlled so precise definitions are also necessary. In the real world weather, traffic, hills, stoplights, safety and scores of other variables crowd out much of the precision. We’re left with ballpark definitions. So that’s mostly where I’m going with the following – kind of a mix of science and real world training.

Aerobic threshold (AeT). This is a relatively low level of intensity marked by light breathing and the feeling that you could maintain the effort for a few hours. It occurs at about 60% of your aerobic capacity or at about 70% of max heart rate or around 80% of lactate threshold. A ballpark way of determining your aerobic threshold is to subtract 30 beats per minute from your lactate threshold (see below) heart rate. In a sport science lab aerobic threshold is usually defined as the intensity at which lactate just begins to accumulate above the resting level. For more info. 

Anaerobic threshold (AnT). This is usually determined in the lab by a gas analysis “ramp” test while running on a treadmill or pedaling an ergometer. A mask with a breathing tube is placed over your nose and mouth allowing the monitoring system to measure how much oxygen you breathe in and out. The difference between these is the oxygen your body is using to produce energy. At a low intensity at the start of the test you are burning mostly fat, but as the test intensity gradually increases more glycogen (storage form of carbs) is used. At the effort level where glycogen becomes the dominant fuel you are crossing the threshold between aerobic and anaerobic exercise. The AnT effort is often referred to as “redlining.” It’s common for well-trained endurance athletes to be able to sustain their AnT effort for about an hour (see FTP). A common field test for determining AnT involves a 20-minute time trial after which 5% is subtracted from the average heart rate, speed or power. AnT is sometimes referred to as the “lactate threshold.”

Lactate threshold (LT). This is quite similar to AnT (to everyone except sport scientists), but a major difference is that it is commonly determined by measuring the amount of lactate in the athlete’s blood during a ramp test in a lab rather than measuring oxygen consumed. When the lactate volume in the blood reaches 4mmol/L (“millimoles per liter”—a tiny amount) the athlete is assumed to be at LT. As with AnT, LT can be maintained for about an hour (see FTP). For more info. 

Aerobic capacity. This is the same as VO2max which refers to the “maximum volume of oxygen” an athlete can use per minute relative to body weight to produce energy during an all-out, sustained effort of a few minutes that is well above the AnT. It’s also usually determined in a lab by using a gas analysis ramp test that lasts for several minutes. In such a test the workload is increased every few minutes (usually 3 minutes) until the athlete can no longer continue. The amount of oxygen (in milliliters) used per minute per kilogram of body weight at around the time of stopping the test is the athlete’s VO2max. In elite athletes the VO2max is often in the 70s or 80s with even a few testing into the 90s. Generally, the more aerobically fit an athlete is, the higher the VO2max.  Highly trained endurance athletes can usually sustain their VO2max effort for around 5 minutes. So a simple (but painful!) field test of aerobic capacity involves doing a 5-minute time trial to determine your VO2max speed, pace or power. For more info. 

Anaerobic capacity. This is a measure of how much maximal power or speed an athlete can produce in an all-out sprint effort lasting only a few seconds, usually 30. For more info. 

VO2max. See “aerobic capacity.” For more info.  

Functional threshold power or pace (FTP). This is an excellent concept created by scientist Dr. Andy Coggan. It refers to the power or pace (or speed) that an athlete can sustain for an hour since that is commonly how long well-trained athletes can maintain their AnT or LT pace or power in a race effort. This concept is athlete-friendly since it simplifies the explanation of “AnT” and “LT” making it no longer necessary to understand lactate levels or gas analysis to grasp the most important part of the concept. The 20-minute test described in “AnT” above may be used to determine FTP. There is also a 30-minute test for determining FTP. Knowing your FTP allows you to establish training zones based on power. For more info.  

Sleep and Recovery, Part 2

The following is a continuation of my last post on the same topic - sleep as the primary producer of recovery for athletes. Both are excerpts from a book I’m currently writing with the working title of Fast After 50. In the Part 1 post a reader caught a mistake I made relative to slow wave sleep. It should have said … “the frequency of the brain’s electrical activity becomes quite slow.” I had said “the amplitude of the brain’s…” I corrected it. These are the sorts of things that usually go uncaught until the final product is on the bookshelves. Your input is always appreciated and taken seriously. It’s too bad I can’t post the entire book here for you to read and comment on as that would make it a much better product, but I don’t think my publisher would be too keen on that. I have just one more chapter to write, a few problems to clear up and then it will be ready for editing and, eventually, publishing. While I’ve learned a lot, it’s been a challenge to write and I’ll be glad to get a break before starting on my next project (more on this later). It’s been a huge project as a paragraph can sometimes take an hour to write because of all of the research checking needed. But I love doing that. Here’s Part 2 of Sleep and Recovery.

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While there is still a lot to be learned about sleep, it appears that each stage has a specific, essential purpose. The two with which we are most concerned now are the REM and slow wave (N3) stages.

REM is the truly high quality stage of sleep when a lot of important recovery stuff happens. REM is also when you do most of your memorable dreaming. This stage lasts for a few minutes at a time and makes up 20 to 25 percent of your sleep time if you have a full night of sleep. REM happens about every 90 minutes to two hours with non-REM or brief awakenings making up the in-between times. During REM the tissue-building hormones testosterone and estrogen are released into the body to aid recovery. These hormones are categorized as anabolic steroids meaning that they promote tissue, muscle and bone growth and repair. They also have a positive effect on the cellular properties that improve endurance performance. Testosterone is the more potent of these two. Men produce about 20 times as much testosterone as women, but women’s bodies are more sensitive to it. Since REM occurs late in a night’s sleep cycle, artificially shortening your sleep by awakening to an alarm clock may well diminish the release of these hormones thus hindering full recovery.17,18 The negative results may not be too great after a night or two of this, but chronically shortening your natural sleep cycle is likely to have a long-term effect on training quality and performance.

The other critical sleep stage for recovery is slow wave (N3) that generally starts around an hour after falling asleep and recurs several times during the first half or so of the night. During this time your body experiences a rush of growth hormone (GH) that also promotes muscle growth and bone repair among other things. Nearly half of your daily GH secretion occurs during this stage.19 Short of losing an entire night of sleep, you’re unlikely to miss your daily dose of growth hormone. But since aging reduces the total amount of growth hormone your body produces you can’t afford to miss any sleep at all.20,21,22 Unfortunately, slow wave sleep duration is shortened in older folks as we tend to wake up more often.23 In college-aged youth, slow-wave sleep makes up about 19 percent of their sleep time. For us old folks it’s more like three percent.20

Overall, with aging there is a tendency for an earlier sleep onset in the evening, an earlier morning awakening and more fragmented and shallow sleep throughout the night. This further decreases the release of the anabolic hormones testosterone and GH.

Another hormone is released into the blood stream while we sleep—cortisol.24 Its primary function is to prepare the body to cope with stress by increasing blood sugar (we’ll investigate the downsides of this in Chapter 8) and compromising the immune system. It’s also been shown to slow the healing of injuries25 and decrease bone formation.26 All of this hormone stuff makes for a double whammy.

To help maximize sleep time there are several things you can do besides wearing blue-blocking glasses in the evening, which may make you feel a bit weird. I expect you are already familiar with the most common ones—avoiding caffeine in the late afternoon and evening, not working out intensely in the four hours or so before bedtime, maintaining a calm and quiet environment before going to bed, following a regular sleep schedule and bedding down in a dark and cool room. But there are others.

Go light on alcohol in the evening as it has a rebound effect that can wake you later from an otherwise sound sleep. While alcohol doesn’t seem to negatively affect slow wave sleep, and may even be beneficial for it, it has been shown to reduce REM sleep duration.27 I also know of some who take a melatonin supplement in the evening to promote drowsiness. I wouldn’t recommend that as typically when a supplement is used to exogenously (from outside the body) promote some functional change, the body responds by reducing or even halting its natural production of the targeted product and by becoming less sensitive to it. A strange alternative solution that some studies have found and confirmed is drinking a glass of tart cherry juice in the evening. I know that sounds weird, but it seems to work. The aging subjects in these studies had an increase in melatonin production and improved sleep compared with a placebo.28,29,30

When you eat and what your evening meal is made up of may also affect your night-time sleeping. As your mom told you when you were a kid (of course, you didn’t believe her then): a late evening meal or pre-bedtime snack reduces sleep quality.31 So don’t chow down right before going to bed. One study, and I want emphasize only one so far, has shown that the foods you eat late in the day may affect how well you sleep.32 University of North Dakota researchers looked at which type of food was most likely to improve sleep, and, conversely, which may have negative consequences for snoozing. Forty-four adults ate either a high-protein, high-fat, high-carbohydrate or a balanced control diet before retiring for the evening. They did this over a four-day period and crossed over so that each subject ate all of the four meal types. They went to bed after each of the meals and their sleep quality was observed. When eating the high-protein meal their sleep had the fewest interruptions. The high-carb meals produced the least restful sleep.

I want to once again emphasize that sleep is the single most important thing you can do to speed your recovery in order to produce high-quality training while avoiding setbacks due to injury, illness and overtraining. The next most important producer of recovery is nutrition. That’s where we’re headed next.

References

17. Penev PD. 2007. Association between sleep and morning testosterone in older men. J Sleep 30(4):427-32.

18. Penev P, Spiegel K, L'Hermite-Balériaux M, et al. 2003. Relationship between REM sleep and testosterone secretion in older men. Ann Endocrinol 64(2):157.

19. Mehta A, Hindmarsh PC. 2002. The use of somatropin (recombinant growth hormone) in children of short stature. Paediatr Drugs 4(1):37-47.

20. Van Cauter E, Leproult R, Plat L. 2000. Age-related changes in slow-wave sleep and REM sleep and relationship with growth hormone and cortisol levels in healthy men. J Amer Med Assoc 284(7):861–868.

21. Oh MM, Kim JW, Jin MH, et al. 2012. Influence of paradoxical sleep deprivation and sleep recovery on testosterone level in rats of different age. Asian J Androl 14(2):330-4.

22. Antines IB, Andersen ML, Baracat EC, Tufik S. 2006. The effects of paradoxical sleep deprivation on estrous cycles of the female rat. Horm Behav 49(4):433-40.

23. de la Calzada MD. 2000. Modifications in sleep with aging. Rev Neurol 30(6):577-80.

24. Copinschi G, VanCauter E. 1995. Effects of aging on modulatiuon of hormonal sevretions by sleep and circadian rhythmicity. Horm Res 43(1-3):20-4.

25. Ebrecht M, Hextall J, Kirtley L, et al. 2004. Perceived stress and cortisol levels predict speed of wound healing in healthy male adults. Psychoneuroendocrinology 29(6)798-809.

26. Knight RP, Kornfeld DS, Glaser GH, Bondy PK. 1955. Effects of intravenous hydrocortisone on electrolytes of serum and urine in man. J. Clin. Endocrinol. Metab. 15(2):176-81.

27. Ebrahim IO, Shapiro CM, Williams AJ, Fenwick PB. 2013. Alcohol and sleep I: effects on normal sleep. Alcohol Clin Exp Res 37(4):539-49.

28. Howatson G, Bell PG, Tallent J, et al. 2012. Effect of tart cherry juice (Prunus cerasus) on melatonin levels and enhanced sleep quality. Eur J Nutr51(8):909-16.

29. Pigeon WR, Carr M, Gorman C, Perlis ML. 2010. Effects of a tart cherry juice beverage on the sleep of older adults with insomnia: a pilot study. J Med Food 13(3):579-83.

30. Garrido M, González-Gómez D, Lozano M, et al. 2013. A Jerte valley cherry product provides beneficial effects on sleep quality. Influence on aging. J Nutr Health Aging 17(6):553-60.

31. Crispim CA, Zimberg IZ, dos Reis BG, et al. 2011. Relationship between food intake and sleep pattern in healthy individuals. J Clin Sleep Med 7(6):659-64.

32. Lindseth G, Lindseth P, Thompson M. 2013. Nutritional effects on sleep. West J Nurs Res 35(4):497-513.

Update on Prescription Sunglasses

I just got a new pair of Oakley prescription sunglasses from my sponsor, ADS Sports Eyewear in Richardson, Texas. I used to think that I only needed one pair of sunglasses and they would take care of all my needs. But then Michael at ADS convinced me last year to try some activity-specific designs. So they made me a pair of clear lenses for everyday use. They were made using an Oakley Bottle Rocket frame that’s usually used for sunglasses. They’re now my favorite glasses for reading, watching TV, driving and everything else I do when a dark lens is not needed.

Then they designed a pair of sunglasses for when I play golf. It made a big difference. I no longer have to adjust my head position for focus to address the ball. It’s in focus as soon as I look down. And after striking it, chasing the ball with my eyes is also no problem. However, my score is just as bad. If they could only fix that as well.

Remarkably, the golf sunglasses didn’t work as well when riding my bike. The focus for the handlebar device wasn’t quite right. That certainly speaks to how precise their design is. So they made me a pair of Oakley sunglasses I can use on the bike and for everyday wear. This time I mentioned to Michael that my right ear is slightly lower than the left one which screws up the progressive lens focus since the glasses sit just ever so slightly crooked on my face. So he adjusted the focal point for the right eye. It’s amazing what that’s done for close-up activities such as reading my smart phone.

I never knew there was so much that could be done with sunglasses to help them better fit my needs. And now he tells me that the prescription range for their Oakley products is changing for the better, too. It used to be that the Rx limits for lenses were +2.00 to -3.00. Now they’re able to make authentic Oakley True Digital lenses from +4.00 to -6.00 in select Oakley frames. So if you have really bad eyes now you can get prescriptions glasses made. And they’ve added a lens-only purchase option if you like your current frame and want to only replace the lenses because they’re scratched. Within two weeks you can have new lenses installed and save some money since you don’t need to purchase the frame.

A number of my blog readers have reported how well they’ve been treated by ADS, how competitive their pricing was, how quickly they got their glasses and how satisfied they are with them. If you’re in the market for new glasses this season I’d highly recommend checking them out. 

 

Sleep and Recovery, Part 1

The following is an excerpt from a book on aging I’m now writing. The working title is “Fast After 50.” Even though the book’s market is 50+ aged athletes I’m sure much of what I’ve written here on sleep is applicable across the board regardless of age. Far too many athletes, both young and old, get too little sleep. That shows up as lackluster training and poor performance. Sometimes the athlete doesn’t have a clue that he or she is simply not getting enough sleep. Sleep is critical to adaptation and fitness. Too little sleep can greatly reduce the benefits of androgenic hormones such as growth hormone and testosterone. Many could improve by simply getting more snooze time. Since this is a rather long piece I’m going to post it in two parts. Here is Part 1. The book, by the way, is due to be on the shelves around the end of the year.

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The purpose of sleep is the growth and rejuvenation of the body’s many systems such as the muscular, skeletal, immune, nervous and other systems. This is your primary means of recovery from training stress. There is nothing you can do that will help you recover faster or more completely. Sleep is not something to mess around with and yet some do by shortening their sleep time in order to pack more stuff into their lives. It’s quite common for athletes to stay up late watching their favorite TV shows and then set an alarm so they get up early the next morning in order to fit in a workout before heading off to work. If you depend on an alarm clock to wake you then you probably aren’t getting enough sleep—or enough recovery. Going to bed earlier would more than likely improve your performance. That single lifestyle change may even improve your life in other ways.

Several studies have found that the amount of sleep you get is closely associated with not only your health, but also your longevity. Short sleep durations have been shown to increase the risk of obesity, heart disease and type 2 diabetes.7,8,9 (Patel, Ferrie, Reynolds) Conversely, those who report regularly sleeping six to seven hours per night appear to have long lifespans.10 (Kripke) Interestingly, sleeping more than seven hours nightly has been associated in one study with a shorter life.8 (Ferrie) Note that “association” doesn’t mean “cause,” but rather that the two were found to occur together. There could be a cause effect, but this isn’t known with any degree of certainty. Even if long sleep was causal this shouldn’t be taken to mean that setting an alarm to wake you up after seven hours in bed is the key to a long life. An innate sleep duration is probably best for longevity as well as health. Your normal nightly sleep duration is probably determined by genetics11 (He) and shouldn’t be artificially shortened. It is probably most beneficial when you wake up naturally rather than to the buzzing of a clock.

To appreciate the benefits of sleep for recovery it’s necessary to understand sleep. What happens during slumber that produces renewal so that you can do another hard workout? Let’s start by finding out what goes on in your body when you’re asleep.

Sleep researchers divide your snooze time into two broad periods: rapid eye movement (REM) and non-rapid eye movement (NREM).12 (Dement) Non-REM is further divided into three stages called N1, N2 and N3. The last of these is referred to as slow wave sleep because the amplitude of the brain’s electrical activity becomes quite low. In a full night of normal sleep your body progresses through the N1, N2, N3 and REM stages several times. Slow wave sleep makes up much of the early stages of a full night of sleep with most of the REM time occurring in the latter half of the night. These two stages have a lot to do with how well you recover so we’ll take a closer look.

Your body operates on a built-in clock called the “circadian rhythm.” This “clock” is set by how much light enters your eyes. In the evening, around sunset, your clock initiates the release of a hormone called melatonin from the pineal gland in the brain as your body temperature is also lowered. This produces the drowsiness and yawning that is the start of the N1 stage. As with most hormones, as you get older melatonin production decreases.13,14 (Sack, Goldenberg) That means sleepiness for some oldsters may not be as compelling as it is for younger athletes. Then again, many older athletes find that they become drowsy much earlier in the evening than they did when young and often fall asleep in a chair long before making it to the bedroom. These older athletes also tend to wake up earlier in the morning.14,15 (Duffy, Goldenberg) Generally, the circadian clock for seniors is not as rhythmic as it was when younger.

A specific type of light, called “blue light,” which is produced by the sun, interferes with the production of melatonin. The light bulbs in your home also give off some blue light, not nearly as much as the sun, but possibly enough to hinder melatonin release thus keeping you awake longer in the evening. To stimulate a melatonin discharge in order to start feeling drowsy you can turn off most of the lights before bedtime. There are also special blue-blocking glasses that look like sunglasses and can be worn in the evening if you must be in a bright, artificially lit room.16 (Burkhart) You can search the web to find such products.

References

7. Patel SR, Ayas NT, Malhotra MR, et al. 2004. A prospective study of sleep duration and mortality risk in women. Sleep 27(3):440-4.

8. Ferrie JE, Shipley MJ, Cappuccio FP, et al. 2007. A prospective study of change in sleep duration: associations with mortality in the Whitehall II cohort. Sleep 30(12):1659-66.

9. Reynolds AC, Dorrian J, Liu PY, et al. 2012. Impact of five nights of sleep restriction on glucose metabolism, leptin and testosterone in young adult men. PLoS One 7(7):e41218.

10. Kripke DF, Garfinkel L, Wingard DL, et al. 2002. Mortality associated with sleep duration and insomnia. Arch Gen Psychiatry 59(2):131-6.

11. He Y, Jones CR, Fujiki N, et al. 2009. The transcriptional repressor DEC2 regulates sleep length in mammals. Science 325(5942):866-70.

12. Dement W, Kleitman N. 1957. Cyclic variations in EEG during sleep and their relation to eye movements, body motility and dreaming. Electroencephalogr Clin Neurophysiol 9(4):673–90.

13. Sack RL, Lewy AJ, Erb DL, et al. 1986. Human melatonin production decreases with age. J. Pineal Res. 3(4):379–88.

14. Goldenberg F. 1991. Sleep in normal aging. Neurophysiol Clin 21(4):267-79.

15. Duffy JF, Dijk DJ, Hall EF, Czeisler CA. 1999. Relationship of endogenous circadian melatonin and temperature rhythms to self-reported preference for morning or evening activity in young and older people. J Investig Med 47(3):141-50.

16. Burkhart K, Phelps JR. 2009. Amber lenses to block blue light and improve sleep: a randomized trial. Chronobiol Int 26(8):1602-12.

London World Triathlon Series Stats

The International Triathlon Union (ITU) produces a series of eight races around the world with separate elite and age group competitions. The London event is the weekend after next in Hyde Park.

The race sent me an infographic that summarizes much of the number data about the race last year. (Click on the figure to enlarge it.) Some stats stood out for me:

Participants

            Men - 62%

            Women - 38%

Participant average age – 43

Training time – 90% more than 5 hours/week

Families – 55% of age groupers have children

Bike average cost - £1550 (about $2600)

Has anyone seen similar stats for US and worldwide triathlon racing? I used to have such stats for the US but they are no longer accurate, I’m sure. If you have such data and wouldn’t mind sharing I’d appreciate it. It needs to be current – within the last 3 years.  I’d be interested in the same for cycling and running. Once I’ve vetted the data I’ll post it here for everyone. Thanks!