Long, slow distance training
A new slant on an old training concept

In the 1960’s, Arthur Lydiard contended that the most important aspect of conditioning is volume. In the 1960’s his LSD training concepts were revolutionary and insightful, and brought phenomenal success to many athletes who trained under Lydiard.

Metabolically, high-volume training makes sense. There are two main sources of fuel for exercise: carbohydrates and fats. The energy supply from carbohydrate and fat is inversely related. High rates of carbohydrate use reduce combustion of fat. Carbohydrates are used preferentially at very high efforts or at low fitness levels when fat metabolism is underdeveloped.

Conversely, when you teach your body to rely on fat for fuel, your combustion of carbohydrates goes down, thus sparing carbohydrates. This benefits performance in endurance events. You become very fatigued when you run too low on carbohydrates. We store only a very limited amount of carbohydrate (glycogen) in our bodies. Compare this with a relatively unlimited supply of fat. Even an athlete with only 6 percent body fat will have enough fat to fuel exercise lasting for many hours. When you use more fat, you generate more energy and your carbohydrate supply lasts longer.

This sounds good. So why not stick to LSD over the next few months?

1. Misinterpretation of the term
2. New studies pointing to better over-all performance alternatives
3. The law of diminishing returns
4. Specificity
5. It depends

The term

Most people mistakenly think LSD means slow in terms of intensity. Lydiard's formula advocates not just high-volume training but high volume at speeds near maximum steady state. His work with runners found that daily runs of 90 minutes at 70 percent maximum will boost mitochondria 30 percent higher than equivalent time spent at an easier 50 percent effort.

In Lydiard’s words, most training should be conducted close to the highest speed that you can run without going anaerobic. This is the speed where fat metabolism is at its highest.

I find that if you ride long in something below z1, you are not receiving training benefit, just a mild level of fatigue. This fatigue can affect not only the long ride, but successive training sessions. This is akin to negative active recovery, and it might be better to simply take a nap or go watch a good movie.

New studies

Judicious use of high-intensity workouts during early season will not damage or ruin your fitness, but may help to maintain and increase aerobic capacity.
In 2005 and 2006, studies emerged indicating that high intensity interval training can be equally effective as traditional endurance-based training in improving aerobic capacity.

For example, a recent study examined the effect of high-intensity interval sessions on fat and carbohydrate metabolism and lactate concentrations in cyclists who had been training two to three hours per day for years. They replaced some of their endurance miles with two weekly sessions of 6-9 x 5-minute intervals with 1 minute of recovery between. After six weeks, the percentage of energy coming from fat during a one-hour trial had increased from 6 percent to 13 percent. How well this applies to a race lasting more than two hours is unclear.

New findings by Finnish scientists at the Research Institute for Olympic Sports suggest that this one-sided strategy (LSD) may be unnecessarily limiting for endurance athletes and that anaerobic performance can be enhanced w/out increasing training volume or compromising endurance.

These scientists performed a test on a group of 25 runners, training for eight weeks. For the experimental group, 19% of endurance training was replaced with explosive-type training (sprints/strength drills). This experimental group showed improvements (compared to control group, who ran the same total volume of just LSD training) in pure speed, concentric and isometric forces generated during leg extension, muscular force-time, faster neural activation of the muscles (generate more power through more rapid muscular contractions), increase in thickness of quad muscles (nearly double the other group); and the maximum speed and running economy remained unchanged in both groups.

Studies show intensity sprints improved time to exhaustion for subjects. It improves muscle glycogen, another key determinant of aerobic endurance.
High intensity efforts bring up your overall aerobic capacity, which makes you better at all intensities. Researchers have demonstrated that, after a 12-week six-day-per-week program of 45 minutes of running and cycling at a high intensity, fat combustion increased by 41 percent. This was accompanied by reduced reliance on carbohydrates.

There is even a hole in the metabolic fact that miles make mitochondria. It is true that the enzymes of fat metabolism are located in structures within the muscle cells called mitochondria, which are the powerhouses of the cell. Fats are transported into the mitochondria where, in the presence of oxygen, they are broken down to generate energy. More mitochondria mean more fat metabolism, more ATP, and more energy. High-volume training increases the amount and size of mitochondria.

There is, however, a point of diminishing returns. A three-hour run is better at nudging the mitochondria content upward than a 90-minute run, but the gains are offset by the necessity of a longer recovery time between workouts. Studies also confirm that volume and intensity interact to produce even greater gains in mitochondria development.

During the base phase of building miles, it is the daily consistency of training over a period of weeks and months that will boost fat metabolism. Miles may make champions, but those miles should be carefully (and gradually) developed, monitored, and arranged to get the maximum effect.

Specificity—train the way you race

One of the most fundamental rules of training is specificity: your training should replicate the demands of the event for which you’re training. Different events rely on different energy systems, and each discipline requires a specific set of motor skills and neurological adaptations. Endurance sports draw heavily on the aerobic system, but they often require short, high-intensity bursts (any sprint—attack, breakaway, the finish) that call on other pathways.

Endurance training is kind of a misnomer: you can’t really compartmentalize it. It consists of endurance, technique, strength, and speed. You need to maintain good form, which tends to dissipate at slower speeds. The body learns at speed: it is forced to throw off any extraneous movements to battle the resistance.

It depends

‘Easy’ of course, is relative to each one of us. Even Arthur Lydiard said, “There is no easy way.” It always depends.

Training always depends on the athlete—fitness level, lifestyle, level of experience, and myriad other factors. Aerobic adaptations can be achieved in more than one way, and hi-intensity efforts can be incorporated even into training phases primarily emphasizing aerobic adaptations. Even volume can be different for each athlete

For experienced athletes, the maximum steady state equals an intensity of 70 to 75 percent of maximum heart rate. For those just launching their careers, it will be closer to 60 to 65 percent of maximum heart rate.

It is not practical or even possible for most people with full-time jobs and families to build up mileage quickly. The amount of mileage you will be able to train depends on your lifestyle, physical capabilities, and prior training history. Less-experienced athletes may want to build up mileage over a period of many months or even years.

Long rides may tax certain athletes mentally, and cause negative effects.

Think frequency and repeatability for the greatest return on investment. Train hard enough to stress your system and tax yourself a bit, and easy enough so you could repeat the workout tomorrow. Remember that chaos creates change, so mix it up.