If the fastest swimming, cycling, and running you do is in races, you’re not training right. Every triathlon training program should include speed work, or efforts that exceed race intensity. Speed work not only changes your perception of race intensity, making it feel more comfortable, but it also enhances fitness in ways that slower training does not.

There are right and wrong ways to incorporate speed training workouts. Doing speed work the right way is not difficult. A top triathlon training tip is to copy how professional triathletes go about it (which is not to say you should try to go as fast as they do!). Incorporating speed exercises all comes down to obeying these three simple rules.

Rule #1: Do some speed training workouts year-round.

Speed training workouts can be done year round

The term “periodization” refers to the practice of dividing the training process into phases and assigning a distinct fitness objective to each. Traditionally, the first phase, known as the base phase, is all about building general aerobic fitness and endurance through large and increasing amounts of low-intensity training. Speed work is excluded from this phase because maximizing overall training volume is easier when intensity is kept low.

These days, however, most elite triathletes include a small amount of high-intensity swimming, cycling, and running in the base phase, and you should too. The reason is that when speed work is completely eliminated from training, the athlete loses the dimension of fitness that comes from speed work and makes it harder to get it back in later phases.

Just one small dose of high-intensity swimming, cycling, and running per week during the base phase will enable you to avoid digging this all-too-common hole. I recommend doing very short efforts at or close to maximum intensity, such as 8 x 25-yard sprints in the pool and 8 x 20 seconds uphill on the bike or the run.

Rule #2: Keep your total volume of speed training workouts low.

After the base phase of training comes the peak phase. During this period, which should begin 6-12 weeks before a race, you will want to increase your volume of speed work while keeping your overall training volume steady. But even at this time, speed work should account for no more than 10 percent of your total training volume.

Again, let the pros be your guide. In 2012, Iñigo Mujika of the University of Basque Country monitored the training of elite triathlete Ainhoa Murua as she prepared for the London Olympics (where she placed seventh). He found that she spent 10 percent of her total swim training time, 2 percent of her cycling time, and 7 percent of her running time at high intensity. These numbers are normal for elite triathletes and they should be the norm for you too.

While a little triathlon training for speed goes a long way, more than a little is counterproductive. This was shown in a 1999 study involving elite middle-distance runners. For the first several weeks of the study period the runners completed six runs per week, all at low intensity. Then they switched to a schedule of five low-intensity runs and one high-intensity run per week for a few weeks. Finally, they switched to a schedule  of three low-intensity runs and three-high-intensity runs per week. The runners produced the best results in a fitness test when they were doing one run per week at high intensity and got the worst results when they did speed work three times per week.

Here’s an example of a sensible breakdown of training intensities during the peak period of training:

Monday: Rest

Tuesday: Swim 1500 yards w/ 3 x 200 at moderate intensity

Wednesday: Bike 50 minutes w/ 8 x 1 minute at high intensity

Thursday: Run 45 minutes w/ 6 x 3 minutes at high intensity

Friday: Swim 1500 yards at low intensity

Saturday: Bike 70 minutes + run 10 minutes at low intensity

Sunday: Run 10 miles at low intensity

Rule #3: Make your speed work increasingly race-specific as the training process unfolds.

swimming for speed training workout

The format of your speed workouts should evolve from week to week as the training process unfolds. The idea is to make your high-intensity sessions increasingly race specific. What does this mean exactly? It means that your intervals should become longer and slower (while remaining faster than race speed). The reason is that the true goal of speed work is not to make you faster—it’s to increase your fatigue resistance at higher speeds.

In the pool, I suggest starting with 25-yard sprints and moving step by step from there up to 200-yard repetitions. You should include longer intervals in your training as well, but these don’t count as speed work. On the bike and on the run, start with 20-second hill sprints and transition incrementally to intervals of 3 to 5 minutes. Don’t completely give up the really short stuff, though. Sprinkle in a few sprints even during the last few weeks before a race to maintain your highest gear.

Love it or loathe it, speed work is a critical component of effective triathlon training. But there are right and wrong ways to go about it. Now you know the right way.

An interesting new study by researchers at the University of Western Australia investigated the effects of periodization in the training of runners. Periodization is the practice of sequencing workouts in such a way as to maximize fitness for a race of a particular distance on a specific future date. There are different philosophies and methods of periodization, among them traditional linear periodization, which emphasizes high-volume, low-intensity training in the early part of the training cycle and low-volume, high-intensity training in the latter part, and reverse linear periodization, which does the opposite. This new study, published in the Journal of Strength & Conditioning Research, compared the effects of these two approaches as well as unstructured, non-periodized training on fitness and performance.

Thirty recreational runners were separated into three groups. One group practiced linear periodization for 12 weeks, doing high-volume, low-intensity training for six weeks and then switching to low-volume, high-intensity training for six weeks. A second group did reverse, and a third group served as controls, continuing with their normal training routine for 12 weeks. All of the subjects completed a 5000-meter time trial before and again after the 12-week intervention. On average, members of the linear periodization improved their 5K time by 1:16, while members of the reverse linear periodization group saw a bump of 1:52 and controls barely budged, trimming a mere 3 seconds off the initial marks.

The difference between the linear and reverse linear groups’ gains was judged to be statistically insignificant, and so the researchers concluded, “These results do not support linear periodization or reverse linear periodization as a superior method; however, periodized training elicited greater improvements in endurance performance than nonperiodized training, highlighting the importance of planned training structure.”

This is not the only study to have found that the old adage, “There’s more than one way to skin a cat,” seems to apply to periodization in endurance training. Another was conducted by Stephen Seiler and his Norwegian colleagues and published in 2016. This experiment involved a subject pool of 63 cyclists who were also separated into three groups that periodized their high-intensity training in different ways over 12 weeks. One group started with longer intervals and moved toward shorter, faster intervals, a second group did the opposite, and a third group mixed them all together. All three groups improved by equal amounts, and the researchers concluded, “This study suggests that organizing different interval sessions in a specific periodized mesocycle order or in a mixed distribution during a 12-wk training period has little or no effect on training adaptation when the overall training load is the same.”

As surprising as these findings may be to some, they jibe with my experience as a coach. What I have observed is that the one thing a training program must do over the course of time is get harder. And it doesn’t much matter how it gets harder provided certain rules are respected—chief among them, limiting high-intensity work to no more than 20 percent of total training time and punctuating the process with occasional recovery days and weeks. The fundamental goal of training is to build fitness, and workload is the major driver of fitness development. Different combinations of volume, intensity, and workout structure can add up to the same workload, and if they do, their results will be more or less the same (again, if certain guardrails are respected). In the two studies I’ve described, workloads were held constant for the sake of fairly comparing different training sequences, and that’s why the disparate programs yielded similar results.

“But wait a minute,” you say. “In the first study, the two experimental groups improved equally, but they improved without increasing their training workload relative to the control group, which did not improve. So how can you say that increased workload is the alpha and omega of fitness development?”

Excellent point—but you’re forgetting my qualifiers. The vast majority of recreational runners do far less than the optimal 80 percent of their training at low intensity. Before the intervention, virtually all of the subjects in the Western Australia study were likely caught in the so-called moderate-intensity rut. Those subjects who went into both the linear periodization group and the reverse periodization group were given structured workouts with individualized target intensities based on testing—workouts that ensured they were at low intensity most of the time and at high intensity (versus moderate) most of the rest of the time. Meanwhile, members of the control group continued to train as normal, which is to say the continued to slog along in the moderate-intensity rut. And that’s why they didn’t improve, whereas the other groups did.

Once this problem has been fixed, though, the only way to build fitness is to work harder. Obviously, peak performance (which is distinct from peak fitness) requires that an athlete compete in a relatively rested state, which is why many studies have shown improved performance in athletes after a short period of reduced workload, and why a taper period is an essential final phase in the periodization process. But again, increased workload is the one major driver of increased fitness.

Does this mean I put little or no thought into how I sequence workouts in a training cycle, focusing entirely on making sure the training load increases (except during recovery weeks and the taper phase) and the 80/20 Rule is adhered to? It does not. The absence of scientific proof that periodization matters is not proof that it doesn’t matter. After all, there is virtually no scientific proof that high-volume training is optimal for building endurance fitness, and we know with absolute certainty from real-world evidence that it is. Although, as we’ve seen, the relevant science supports my real-world observation that the importance of periodization is widely overrated, I still think it matters a lot more than zero and I put a lot of thought into how I sequence workouts in designing training programs.

Specifically, I believe in the principle of training with ever-increasing race-specificity as the training cycle unfolds. If a runner came to me and asked me to train him to run the best mile he’s capable of, I would design a very different program from the one I would build for the same runner if he asked me to coach him to the best marathon he’s capable of. Both programs would feature a gradual, punctuated build in training load and would respect the 80/20 Rule, but one would get more and more mile-specific and the other more and more marathon-specific. And I don’t care what the science says, I know this runner would not run as fast a mile after following the marathon plan as he would after following the mile plan, nor run as fast a marathon after following the mile plan as he would after following the marathon plan!

The term periodization refers to the practice of dividing the training process into distinct phases, each of which is defined by a specific purpose and made up of workouts that are intended to fulfill its purpose. Simply put, an athlete who practices periodization does different things at different points in the training cycle, whereas an athlete who does not periodize his training does the same thing week in and week out.

To put an analogy on it, an athlete who practices periodization is like a farmer, whereas an athlete who does not is like a factory worker. What sort of work does a farmer do? It depends entirely on when you visit the farm. In one season you may find him planting, in another administering pesticides, and in yet another harvesting. No matter when you visit the assembly line, however, you will find the factory worker putting screws in widgets.

Endurance athletes have not always practiced periodization in its current form. Like most modern training methods that we take for granted today, it had to be discovered. The idea that it is beneficial to train in different ways at different times is not terribly intuitive, which is why even now athletes who are not taught to periodize their training don’t.

While it hasn’t always existed, periodization was not discovered as a single event by a single individual—it’s too complex for that to have happened. Rather, it evolved piecemeal over time, with lots of different athletes and coaches representing a variety of endurance disciplines contributing to its development. In running, the most influential periodization model is the one that was created by the legendary New Zealand coach Arthur Lydiard. In this model, a phase of base-building that features increasing amounts of long, slow running is followed by a strength-building phase that features lots of hill running, then a speed phase dominated by short, fast intervals and finally a racing phase.

Since this model was developed in the 1950s, coaches and athletes have come to the conclusion that such a strict segregation of training types isn’t necessary. In his Hierarchy of Endurance Training Needs, noted exercise physiologist Stephen Seiler ranks “General Periodization Details” fourth in importance out of eight fundamental endurance training methods, remarking that there is a tendency to overrate the impact of sequencing different training stimuli in one way versus another. For example, some marathoners like to do a little bit of very high-intensity track work in the peak training weeks preceding a race, whereas others prefer to do almost all of their uptempo work at speeds closer to race pace. The evidence suggests that either can work.

Where there is less wiggle room is in how stress and rest are managed. Every runner, even those who don’t know the first thing about periodization, understand that their overall marathon training workload should tend to increase as they move closer to race day. But the best results seem to come not when athletes continuously do about as much as their present fitness level allows, as intuition dictates, but rather when they intentionally do significantly less training than they could handle at some times and intentionally overreach—that is, taking on a training load that would break them if they sustained it for very long—at other times—and this is less intuitive.

Most people exercise with a “get in shape, stay in shape” mentality. In a typical scenario, a sedentary person sees an alarming number of the bathroom scale or has a scary doctor’s appointment and starts working out. Initially, he can’t do very much, but as he builds some fitness he does a little more and a little more until he reaches a point where he’s doing about all the exercise he cares to do. From that point on, he follows the same exercise routine for the rest of his life (slight exaggeration to make a point).

Endurance training doesn’t work like that—or shouldn’t. If your goal is to achieve peak performance in a race, you need to train in a way that, to put it crudely, burns you out, so that after the race you need a break and after the break, having voluntarily give up some fitness, you must ease gently back into a new cycle of training.

Several years ago Stephen McGregor, an exercise physiologist at Eastern Michigan University, shared with me some interesting data he collected from professional cyclists. These were athletes who logged all of their training on TrainingPeaks, whose Performance Management Chart quantifies fitness through a variable called chronic training load (or CTL). In most circumstances, CTL is a very accurate predictor of performance. As a general rule, the higher your CTL is, the fitter you truly are and the better you perform in a races and other endurance tests. But in analyzing the data or professional cyclists, McGregor found that, over the course of a season, their CTL and performance decoupled. Early in the season, as the riders increased their CTL, their performance improved as expected. Then, as they maintained their peak CTL into the racing season, their performance level held steady—for a while. But after three months or so of this, their performance level began to decline even as their CTL was maintained.

In other words, the same training that made the cyclists fitter initially burned them out over time. On its face, this seems like an avoidable mistake, but training less in order to achieve a sustainable CTL is no alternative because in that case their peak performance level wouldn’t be as high. Peak fitness and sustainable training loads are simply incompatible, and this is the number-one reason it’s necessary to periodize.

Always remember, you’re a farmer not a factory worker.

If I could clone myself a few times for the sake of taking different paths in life, I would definitely dedicate one of my clones to the pursuit of sports science. This being impossible with current technology, I choose instead to live vicariously through the individual sports scientists who are tackling the questions I would be most interested in tackling if I had my own lab.

One such question (or line of questioning, more accurately) is this: If you could do only one

thing right in your training as an endurance athlete, what should it be? In other words, what is the single most beneficial training practice you could employ as an endurance athlete seeking improved performance? And if you were already doing this one thing, what then is the next most impactful method you could incorporate?

If we were to pursue this line of questioning all the way through to the end, we would end up with a sort of hierarchy of endurance training needs. How useful that would be! Well, guess what? This hierarchy already exists, created by one of my very favorite sports scientists, Stephen Seiler, who drew upon his encyclopedic knowledge of research on endurance training practices to perform the exercise I just described. With a nod to Abraham Maslow’s famous hierarchy of psychological needs, Seiler’s Hierarchy of Endurance Training Needs ranks eight fundamental training practices in order of proven impact. If there’s a more helpful tool for understanding the big picture of endurance training, I haven’t seen it. So, let’s go through the hierarchy (see Seiler’s own graphical summary at the end of this post):Hierarchy of Endurance Training Needs by Stephen Seiler

1. Total Frequency/Volume of Training

According to Seiler, the single most beneficial thing you can do to improve your performance in endurance racing is to train a lot. The fine print is that in training a lot, you must be sure not to train too much, and you can train more without training too much if you train at low intensity, so what Seiler really means here is that the single most beneficial thing you can do to improve your performance in endurance racing is do a lot of low-intensity training.

2. High-Intensity Training

 Although doing a lot of training exclusively at low intensity will make you fitter than doing a small amount of any other kind of training, you will get fitter still if you combine a little high-intensity training with a lot of low-intensity training. Seiler rates this fact as “well established” in the scientific literature.

3. Training Intensity Distribution

Seiler made a name for himself by discovering the 80/20 Rule of endurance training, which posits that endurance athletes improve the most when they do roughly 80 percent of their training at low intensity and the remaining 20 percent (give or take) at moderate to high intensity. So, the next most impactful thing you can do in your endurance training—if you’re already doing a lot of low-intensity training and a little high-intensity training—is to fine-tune the balance of intensities to bring your training in line with the 80/20 Rule.

Let me add here that applying the 80/20 Rule is usually the first change that I make to the training of the athletes I coach. The reason is that the average recreational endurance athlete does close to 50 percent of his or her training at moderate intensity—way too much. Training more won’t help an athlete who is caught in the moderate-intensity rut because it only exacerbates an existing problem. There is much more to be gained from redistributing the training he or she is already doing and then taking advantage of the reduced stress and fatigue levels resulting from this shift to train more.

4. General Periodization Details (Annual)

 Periodization refers to the practice of evolving one’s training over the course of the year in specific ways intended to cause fitness to continually increase. Seiler rates this practice as “likely overrated.” By this I don’t think he means that training shouldn’t evolve over the course of the year but rather that the details don’t matter much. If that’s the case, then I agree wholeheartedly. What does matter is that 1) the overall training workload (which is a function of both the volume and the intensity of training) increase and 2) your most challenging race-specific workouts come later on, when your fitness is near peak levels and it’s getting close to time to race. But the relevant research has shown that within these broad parameters, different periodization practices yield similar results. In other words, where periodization is concerned, there’s more than one way to skin a cat.

5. Sports-Specific and Micro-Periodization Schemes

 According to Seiler, the particular ways in which endurance athletes chose to sequence workouts from day to day and week to week has a “likely modest” effect on fitness. In other words, it doesn’t matter too much whether you schedule recovery weeks every third week or every fourth week. Of course, it’s vitally important that you balance hard work and rest/recovery in such a way that your body neither accumulates fatigue over extended periods nor detrains between challenging training stimuli, but as with macro-periodization, there’s more than one way to achieve this balance.

6. Training-Stimuli Enhancement

“Training stimuli enhancement” refers to practices such as training at high altitude and training in a glycogen depleted state. Seiler believes that such things are worth doing but that the effects are “individual and condition specific.”

7. Pacing Training

Fitness is not the only determinant of race performance. To get the most benefit from any level of fitness in competition, an athlete must pace himself or herself effectively, and this objective is aided by practicing pacing in training, which may also serve to stimulate pace-specific fitness adaptations. Seiler rates this practice as “potentially decisive if everything else is done right.”

8. Training Taper

Although your fitness level won’t change much in the last week or two before a race, no matter what you do, what you do in the last week or two before a race can have a big impact on how you perform nevertheless. Tapering is the art (Stephen Seiler might say science) of altering your training prior to competition to ensure that you’re rested—but not too rested—and physiologically primed for a maximal effort. Science has shown clearly, for example, that endurance athletes race better when they include high-intensity work in their taper than when they do everything at low intensity. Seiler rates tapering as “potentially decisive if you have one isolated competition. . . and everything else is done right.”

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