Your Easy Days Are Too Hard And Your Hard Days Are Too Easy

Why your easy days are too hard, your hard days are too easy, and how to find the perfect balance to maximize your training.

This article was originally published in the May/June 2012 issue of Inside Triathlon magazine.

Neal Henderson has successfully coached a wide variety of athletes, triathletes and cyclists ranging from age groupers to Olympians by sticking to a fundamental training philosophy—one he believes to be the key to endurance performance. Contributing editor Aaron Hersh interviewed Henderson, who is the director of sport science at the Boulder Center for Sports Medicine in Colorado and owner of Apex Coaching, on this philosophy and how it can be used to improve any athlete’s performance. The following is a sampling of their conversation.

The Philosophy

The objective of all training is to achieve the greatest level of adaptation, not to become the most tired. Many times people train to get tired or to burn calories. Go ahead and burn calories if you want to work out and lose weight. That’s all well and good, but if you’re a high-performance athlete, whether your definition of high performance is finishing your first Olympic-distance race or trying to win the Ironman World Championship, the best way to achieve your goal is to have an adaptive response to training, which results in improvement, not to simply do more training. You want to do training that has an effect. There are some consistent themes in the way the most successful athletes train, and that’s really about a polarization of effort—workouts are either extremely easy or extremely hard, with almost no training in the middle, and that’s the crux of my philosophy.

Draw Boundaries

The first step in creating a polarized training plan is evaluating the athlete in some objective way. Some of the standard laboratory-type tests I use often include a lactate profile test, occasionally a VO₂max test, and an oxygen utilization test to find the mix of carbohydrates and fats an athlete uses for fuel at various intensities. In some cases, we’ll look into less commonly measured things, such as anaerobic power. The lab testing is typically done at the very beginning of the season, or when I start working with the athlete, and then three or four months later, to assess change.

The next part after gathering an athlete’s physiological capabilities is to look at field responses. We perform tests similar to the lab protocols, but we’re out cycling or running on the road. For example, it’s typical that we would do a lactate profile and VO₂max test both on the bicycle and in the lab, and then just the lactate profile test while running. We see clear differences in the threshold and heart rates between the two sports, so we conduct tests for both. To conduct these tests outside the lab, we need to have some objective measure of power on the bicycle, usually a power meter, and we use pace or speed while running. Within several days of doing the objective lab measurements, I would have people do what we call power profiling, where we look at maximum power for five seconds, five minutes and 20 minutes. This testing procedure is espoused by Andrew Coggan, [Ph.D.,] author of Training & Racing with a Power Meter. Typically a five-minute power test is analogous to VO₂max. The 20-minute maximal effort is analogous to the lactate threshold power determined by the laboratory testing. One difference that I have in testing procedure compared to Dr. Coggan is to have the athlete complete all testing in just one session, instead of over multiple days.

From those field tests we get some comparisons for things like an athlete’s preferred cadence on the bike. When we do the lactate profile test in a lab, everyone holds a more consistent 80 to 100 RPM, whereas when they’re out in the field they’re going to push whatever RPM, and we’re going to get an idea of what they like to use. When running, we get a look at their perceived effort, their speed, heart rate and their pace. Lot of times we’ll even do some video taping to get a look at the mechanics of how they’re moving, as well.

In most cases, there’s not going to be a dramatic difference between an athlete’s performance inside and outside the lab, but when there is, that always raises a little red flag for me. In some cases, people actually underperform in the field relative to what they’re doing in the lab. When that happens, I’m going to look at their cadence and their pacing. That’s often a lesson for the athlete. Field-testing might be something, depending on where an athlete needs to make improvements, that we do more frequently, every four to eight weeks.

We use the data from the lab and field tests to establish the athlete’s training zones. The zones used by different training systems, whether it’s Joe Friel’s Training Bible, Carmichael Training Systems or what we set up at the Boulder Center for Sports Medicine, the zones are not typically dramatically different. Where we might find some differences is in the amount of prescribed training at these different levels. I prescribe extremely hard training and extremely easy training, because it is at those extremes when the body is going to be stressed. And that’s when we are going to have the adaptations and the improvements. And ultimately, that’s what I am looking for: I want to see change. I want to see the athlete improve. I don’t want to see an athlete just be tired, or just be fit—I want them to be high performing.

The Foundation of Endurance Performance

Two-thirds to three-fourths of all training performed by the athletes who I work with is done at a fairly easy effort—what I call steady-state aerobic base pace. Aerobic base and active recovery, or Zone 1 and Zone 2 training (see chart on page 68), are going to make up the lion’s share of training, whereas most athletes spend too much time in Zone 2 and 3, thinking it is easy enough. Aerobic base workouts need to be performed at a low enough intensity that the athlete can recover from their high-intensity training and build a very large training volume base. The adaptations that we get from the low-intensity training, the steady-state aerobic base training or whatever you like to call it, are an increase in economy and efficiency. We have more fat utilized as fuel at any intensity level. Within the body you have two different fuels that are primarily used during endurance exercise: carbohydrates and fat. Protein is only used for energy production to a very small extent. At lower-intensity exercise you’re going to have a more even mix of carbohydrate and fat used. As you work harder, there is a progressive shift to using more and more carbohydrates. Once an individual is near their threshold effort, the intensity they can do for one hour, they are using almost exclusively carbohydrate fuel. Carbohydrate can only be stored in limited quantities in the body—in muscle glycogen, liver glycogen and blood glucose. We also have a limited capacity to take in and process carbohydrate while we are exercising, and as intensity increases, the body can process less and less carbohydrate. When you run out of that precious carbohydrate fuel, intensity will drop. Fat calories stored within the body, even in a very fit individual, are essentially unlimited, so training the body to metabolize fat is critical to endurance performance because it spares precious glycogen stores needed to go fast.

When we train at low intensities, we develop an increased ability to oxidize (metabolize) more fat at any given intensity. So, let’s just say that at a seven-minute-per-mile pace an athlete with poor aerobic efficiency in terms of utilizing fat may derive 50 percent of all his calories from carbohydrates and 50 percent from fat. With more aerobic base intensity training we could see that ratio shift over maybe a two- to three- to four-month period, so he’s burning 60 to 70 percent of those calories for that same running pace from fat and only 30 to 40 percent from carbohydrates.

An individual who has more aerobic efficiency—the ability to spare glycogen and use more fat as a fuel at any given intensity—is going to be at an advantage versus somebody who uses more carbohydrate and has to ingest more and then has to regulate intensity to digest those carbohydrates. Low-intensity training allows athletes to eventually exercise at a higher intensity at the end of a long training session or a race because they spare glycogen.

RELATED – Train Like Crowie: The Importance Of Slower Sessions

Precisely Stressing the System

Lactate threshold is the exercise intensity where the body starts producing more lactate than it is able to remove, so it begins to accumulate. Lactate itself is not a bad thing. Lactate does not cause fatigue, but there is an association between the point that lactate levels elevate and fatigue. When we train at an intensity just below our threshold, there is a very high influx of lactate being produced by the muscles and being metabolized and used as fuel. The main objectives of high-intensity training are both to increase the production of lactate and, more critically, increase your body’s ability to clear the lactate. Training just below lactate threshold is where we see the greatest increase in one’s ability to clear and re-use the lactate.

Given this, the majority of hard training is best done just below the lactate threshold to maximize the body’s ability to clear lactate. This training adaptation increases your maximum sustainable pace and power, which moves your lactate threshold level up to a faster speed.

Some athletes make the mistake of doing their steady-effort, hard workouts at an intensity too low to maximize lactate clearance—many people call it “tempo” training. In other words, many people spend too much time in Zone 3 during hard training (see chart on page 68) instead of Zone 4. When most people think of tempo training, they think of an intensity that creates a slight increase in blood lactate. I do very little tempo-intensity training with the athletes who I work with. This is counter to many other coaches out there. I try to limit that kind of training to no more than 10 or 20 percent of training volume. On the other hand, some individuals cross over and go above their threshold, into Zone 5, during long interval workouts instead of staying just below. Once you cross over your threshold you see a significant increase the in activation of your sympathetic nervous system, which is effectively activating the “fight or flight” response and signals that you’re under stress. That’s what increases your levels of cortisol, a stress hormone, and will retard recovery from the workout, and you’ll see a pronounced increase in the fraction of carbohydrate used for energy when you cross over. A super-threshold effort (Zone 5) is far more strenuous on you than a sub-threshold effort, and a sub-threshold effort can be sustained much longer. You might be able to do workouts that are 3 x 15 minutes or 2 x 20 minutes of sub-threshold and not feel exhausted. Whereas if you did, say, 3 x 10 minutes or 4 x 8 minutes of above threshold, you’d be pretty shot. And you’d only have accumulated 30 to 32 minutes of super-threshold training versus 40 to 45 minutes of sub-threshold training, and you only need about 48 hours to get going again after the sub-threshold workout. Recovery from super-threshold intensity is going to take longer—closer to three days before you’re recovered and able to do another quality session—which reduces your overall training density. That’s why doing hard efforts at lower, sub-threshold intensities increases the total amount of quality training time an athlete can accumulate.

Even though the majority of hard training is below race intensity, it conditions the body, when rested, to sustain super-threshold intensity on race day because the body is more able to clear lactate. When you look at what the best endurance athletes have done historically, and I don’t care if you go back 50 or 100 years, you see a very high fraction of training done at slow and steady efforts, and they have always done more sub-threshold than super-threshold training.

Our next intensity level is VO₂max intervals, or intervals at Zone 6, which is another specific, critical training mode that many people don’t do enough. In other words, when athletes do intense workouts, they are typically doing these workouts in Zone 5 rather than Zone 6. VO₂max running pace is all-out one-mile speed. Cycling VO₂max power is the highest power an athlete can sustain for five minutes. Your heart rate at the end of a four- to eight-minute VO₂max effort should yield your maximum sport-specific heart rate. You can only operate at some percentage of your threshold during an endurance race, so you need to bump up your threshold to increase your sustainable race pace. VO₂max work pushes up the ceiling.

A set of 10 30-second efforts with 90-second recovery done during a moderately long session is a typical  VO₂max workout for an Ironman athlete, who is going to do significantly less VO₂max-intensity work than a short-course athlete, and when they do those intervals they’re going to be shorter duration with longer recovery.

Apply it Yourself

The best way for an amateur athlete to apply this philosophy without great access to knowledgeable resources is actually fairly simple. Regardless of total training volume, easy aerobic training still makes up the majority of an athlete’s training time. I’ve worked with a lot of successful age-group athletes training just 12 hours per week. Even at this relatively modest total training volume, two-thirds of that training is done at a steady-state aerobic level, with one key weekly long workout in each sport. In the swimming session, mechanics, in addition to fitness, must be stressed. For long-course athletes, a nonstop swim of 30 to 60 minutes or more is also an important factor that is often overlooked. A 20- to 30-minute steady swim is adequate for short-course racers. On the bike, it’s a steady long ride and again, long is relative to the athlete’s race distance. For short-distance racers, it could be two or three hours at the tops. Long-course athletes will likely be in the four- to six-hour range with athletes racing any distance performing short five- to 10-second burst sprints every 15 to 20 minutes to get neuromuscular work in addition to the primarily aerobic base efficiency building work. Running is the same thing. The key session may be a one- to two-hour long run, again depending on race distance, incorporating short, neuromuscular, alactate sprint-type efforts every other week (see chart on page 72 for more information on alactate training). For an Ironman athlete, we often try to build up to a single session near race distance, running between 18 to 24 miles depending on running background, history, injury propensity, things like that, and cycling typically between 110 and 120 miles. I like to go a little bit over race distance on the bike to build confidence and general endurance.

The next important effort level to complete each week is a sub-threshold, or Zone 4, type of interval swimming, cycling and running. In the pool, long intervals such as 300m to 500m repeats are ideal. In cycling, it’s ten- to 20-minute long intervals for a total of 30 to 40 minutes of work. And in running, it’s typically miles or kilometer repeats for a total of 2 to 4 miles.

VO₂max intervals, or intervals in Zone 6, are the final major piece to the puzzle. One such cycling workout for a short-course athlete could be three sets of very short VO₂max efforts. In a two-hour ride, the athlete does 8 x 40 seconds at 140 percent lactate threshold power with 20 seconds recovery at 50 percent threshold power, then a set of 10 30-second efforts at 150 percent threshold power with 30 seconds at 60 percent lactate threshold power for recovery followed by 12 x 20 seconds at 160+ percent threshold power with 40 seconds recovery at 70 percent threshold power with five minutes spinning between each set. A 2-mile brick run immediately follows the ride with 800m at 5K pace, then a 400m jog; 400m at mile race pace, a 200m jog; and 2 x 200m at mile race pace, then a 200m jog.

The Psychology

All the physiological training that we do often ultimately enhances the psychological state, as well. The fittest body with a weak mind doesn’t go anywhere and doesn’t win races. I would rather have somebody come in 10 to 15 percent undertrained but with a 100 percent mental readiness versus someone who’s the other way: 100 percent trained, 90 percent mentally ready. Give me a brain that’s ready. I put my money on the hungry one who’s gotten better rest than the one who’s gotten more hours of training. People think whoever has trained the most is going to win. No, definitely not. No way. It doesn’t work that way. Some aspect of performance on race day is not going to be the training that you’ve done, but the confidence that you have in the training that you’ve done. When you walk to the starting line of a race and you’re confident in the training that you’ve done and you’ve seen objective improvements in your training, you know you can produce more power for this duration, you can run a faster speed at a given heart rate and you can take fewer swim strokes for the same distance. This athlete knows objectively he is better than before. He knows he can now go do this next level; he’s not hoping that he can do it. Objectively, he knows he can. That’s a far different place mentally to go into a race. When you don’t have those objective measures of your training, you go to the start line with a lot more question marks. High performance racing comes from knowledge that you’re ready—it doesn’t come from hope. Hope is not a strategy, as they say.

RELATED: High Intensity For High Performance

Training Zones

Zone 1: Active Recovery

Coach speak: Embarrassingly slow.

Threshold heart rate minus 41 beats per minute or more.

Zone 2: Base

Coach speak: Feels too easy. Conversation pace.

Threshold heart rate minus 40 to 20 beats per minute.

Zone 3: Tempo

Coach speak: Comfortably hard. Can still talk but through noticeable breathing.

Threshold heart rate minus 19 to 9 beats per minute.
Zone 4: Sub-threshold

Coach speak: Hard, but doesn’t leave you fried after 40 minutes of effort.

8 beats below threshold to threshold heart rate.
Zone 5: Super-threshold

Coach speak: Loud internal monologue, bargaining with yourself to maintain the effort.

Threshold heart rate to 8 beats above threshold.

Zone 6: VO2max

Coach speak: Extremely hard effort. Self-preservation instincts kick in.

Threshold heart rate plus 9 beats per minute or more.

Find your zones without a lab

It’s the simple talk test: At the sub-threshold level, your breathing is going to be accelerated but still controlled. If your breathing is on the cusp of control and you’re gasping a little bit, you’re probably above threshold. Another aspect you might find is that sub-threshold effort feels manageably hard. At the super-threshold level, you’re always bargaining and just trying to survive the interval.

Alactate Training

Research published in the Journal of Physiology has shown resistance training increases aerobic efficiency. Individuals with higher strength levels tend to have higher aerobic efficiency. And so in some cases we do some of our strength work not only in the gym but also in neuromuscular strength and power work.

The term “alactate” refers to very high-intensity, short-duration sprint intervals. Despite the name, lactate is still being produced during these repeats, but the intervals are too short to create that lactate feeling in the legs. You slow down simply because you’ve completed your five- or 10-second repeat, not because you couldn’t do it any longer. These intervals are going to be very short efforts, five-, 10-, 15-second efforts with complete recovery between. Those types of efforts are incorporated during a long ride or long run, so I may have athletes doing a three- or four-hour long ride, but they also have to do 10 10-second long maximal sprints, one every 10 to 20 minutes throughout that ride.

Life Stresses Training

Life stress decreases a person’s ability to adapt to a specific amount of training. Your body can only adapt to so much stress, whether it’s coming from training, family or social aspects. So wherever it’s coming from, you have to be aware that there is not a never-ending capacity to adapt and recover. The training volume an athlete requires for success varies based on the other things going on in life. Physical recovery from training is also, of course, very important. When an athlete doesn’t sleep well or eat well, the body’s ability to adapt to the training stress decreases.

RELATED: Is Low-Intensity or High-Intensity Exercise Better for Fat Loss?

“Like” us on Facebook to get the first look at our photo shoots, take part in lively debates and connect with your fellow triathletes.