Why Speed Work is Necessary for Elite Endurance

Table of Contents

  1. Deconstructing the physiology of speed
  2. The problem of only LSD
  3. The necessity of speed work
  4. The focus of an endurance program at different ability levels

First, I am defining “endurance” to be anything at 800m all the way to marathons and beyond. These distances tend to be further broken down into “middle distance” and “long distance” respectively, but they all bear some resemblance as you will see later.

Second, I am defining “LSD” (Long slow distance)  as the accumulation of high mileage without a purpose ON the assumption it will make you faster. This article is not about “LISS” (Low intensity steady state cardio) which is  used for endurance runners and is programmed specifically with a purpose of increase aerobic engine ability. You will see clearly in section 4 when I use examples what I am talking about.

Deconstructing the physiology of speed

Let’s start out with an analogy that I am sure many of you are familiar with.

  • High strength translates to some increased endurance and a higher capacity for endurance.

For example, if I work my way up to a 100 lbs weighted pullup, I will also have the strength endurance to do 15+ pullups. This is because the unweighted pullups are only 60% (for a 150 lbs male) of my 1 rep max and therefore “easy” for my body to do. In essence, the stronger we are, the higher our active and latent potential is for endurance. We can also train to express the latent potential through specific endurance work like longer runs or high intensity exercise such as metabolic conditioning, intervals, etc. On the other hand, training for higher repetitions (or longer runs solely) do not confer the same benefits towards strength or power.

Now, speed development in running has a very important equation which works at all levels of ability.

  • Speed = Stride rate x Stride Length

This equation tells us that our stride rate (how much time each stride takes) multiplied times our stride length (how much distance each stride covers) gives us our speed (distance covered per amount of time). This is very useful information, but there is one catch.

  • Speed improvements tend to be governed by mainly increasing stride length.

At the top levels, stride frequency is similar for all competitors; therefore, improvements most improvements are made only in stride length. There are some exceptions, especially between competitors with large height disparities. Novices should focus only on improving stride length (through strength and speed work) even though they do not have optimal stride rate either. This is because optimal stride rate is developed through sprinting technique. As improvements are made by increasing speed the stride rate will developed optimally as a side effect.

Thus, the question becomes “how do you improve stride length.”

  • The way to increase stride length is exerting more force on the ground in every stride.

The force exerted on the ground must be specific to your bodyweight because that is what you are trying to move. This is called mass specific force (MSF). Here is some further reading with a more detailed explanation if you prefer. Another such article.

Going back our first example, our analogy comes full circle. We know that high amounts of strength translates to increased active and latent potential for endurance. And that strength improves stride length which improves speed. After we have developed a high speed through strength and speed work, we need to develop the capacity to maintain it (which is developing the latent endurance potential from the side effect of high strength). This is where the specific interval and endurance work comes into play.

Thus, if we are running distances competitively, we can logically conclude that:

  • We need a high strength to increase our ability to run faster through increased stride length, and
  • We also need to work our endurance specifically to improve our ability to sustain the lengthened strides.

For middle and long distance we can think of our ability to run faster like a car. The cardiovascular system is a bigger engine and gas tank which powers the car. Increased strength (neuromuscular adaptations) increases the gears in the gear box which allows you to switch to a higher gear at the same engine performance. Increased muscular endurance (aerobic pathways) translates to high performance tires and performance parts which won’t fall apart as power is applied to them. All of these systems must be “upgraded” and worked in concert to improve middle and long distance speed.

The problem of only LSD

LSD (long slow distance) has recently gotten a bad rap and for good reason. If your goal is to improve your distance times there are quite a lot of problems with using LSD only to facilitate improvement. As we discussed in the previous section, there’s 3 things that need to be improved concurrently in order to improve speed at long distances.

  • Increased cardiovascular ability = improvements in engine and gas tank
  • Increased strength (neuromuscular adaptations) = more powerful gears for the engine
  • Increased muscular endurance (metabolically/energy pathways) = improved tires and performance parts

The glaring error with LSD is that it does not improve strength much. The stride length never improves much, which leads to very little increases in speed.

If you take your average person who competes in 5k/10k/marathons and test their strength it will be abysmal. Of course, if you also take a look at their training program they do no speed work or strength training as their whole program probably only consists of LSD with maybe some tempo runs.

While LSD does improve muscular endurance and cardiovascular endurance, we know that high intensity exercise such as intervals produce equal or faster adaptations. One such study is here. It’s easy to find these in PubMed by searching for ‘high intensity lactate endurance’ (no quotes). You will find hundreds of studies showing that high intensity exercise as compared to traditional endurance training shows equal or greater improvements in variables such as lactate threshold, VO2max, and the most important factor which is performance which is shown by improved times. Now, interval gains tend to max out at about 6 weeks, which means to build the cardiovascular base there needs to be some other type of activity. That activity is LISS.

Low intensity steady state cardio is distinguished from LSD in that it is built in as part of training regimen to specifically improve cardiovascular endurance and aerobic pathways. LSD is just running for the sake of running lots of miles hoping it will improve your performance. Some athletes naturally do LISS running, so their “LSD” might be LISS running. Typically, LISS runs are slightly sub-lactate threshold which facilitates increased aerobic adaptations across the system when maintained for 20-60 minutes (depending on the distance). Some lactate threshold running may be used as well. Intervals have shorter rest times between them and maybe some slightly higher intensity.

I’ve ripped on LSD for good reason as you’ll later see in section 4, but it is useful in some cases. For example, there are a lot of elite distance runners who on their off days go out for longer “leisurely” runs. This is known as active recovery and should not be misconstrued as actual training to improve their times. (You will see these runs are not actually “LSD” and not really “leisurely” either).

In conclusion, LSD is for the most part worthless except for active recovery as an “enjoyable activity.” LSD does not show any appreciable improvements in strength, and high intensity exercise shows equal or more improvements for muscular endurance and cardiovascular ability than LSD especially in novices.

However, miles do build champions (in the end). Enough volume WILL elicit enough adaptations (combined with all of the other work above), but at the expense of other productive time. IF a person does not have the time to devote significant portions of time (non-sponsored athletes who can’t train as their job cannot do this), then LSD is basically a time inefficient way to handle training. Training must be planned to be effective, and it must be modulated to a runners current level.

The necessity of speed work

If you read the dragondoor sprinting article in the first section, you know that mass specific force (MSF) is improved with strength, but to translate this to sprinting the muscles need to be trained to apply this force within the very short ground contact times. Application of this force can be done in various ways. The two most common are sprinting itself and plyometrics.

This is why to improve running times, athletes of all distances often have (1) strength training coupled with plyometrics, (2) speed work to improve maximal speed.

  • Improving maximal speed translates to better endurance running because of the same exact principle of how increased strength translates to be increased endurance lifting weights or bodyweight.
  • In other words, high maximum speed gained through strength allows the body to operate a longer stride length. With endurance specific training, this longer stride length can be maintained much longer leading to faster times.

In case you are skeptical of the above analysis, here is one study which shows that increased strength allows the user to operate a longer stride length over a longer period than no strength work. Recognize that these are experienced runners, so a periodized strength program is necessarily for them to make the best improvements as opposed to the non-periodized strength and no strength programs. Of course, the non-periodized strength also showed improvement over the no strength program because some strength work is better than none for not-so-strong endurance athletes. This is why high intensity exercise, especially interval work aimed at increasing maximal speed, helps improve longer runs especially quickly in the novice or intermediate athlete.

Thus, we have our answer for why.

  • We want to improve our strength to translate it to maximal speed. This increases our stride length, and if we can sustain it with muscular and cardiovascular endurance then we can run faster times.

Strength and speed work should be an integral part of an athletes program from novice to elite.

The focus of an endurance program at different ability levels

As stated, for the novice and intermediate the main focus of an endurance program should be first to increasing strength and speed while concurrently developing the ability to run distances. Thus, we aim for a program focused on:

  • Large focus: Integration of strength work such as deadlifts and plyometrics
  • Large focus: Improvement of speed work through high intensity intervals
  • Small focus: longer runs to develop running economy, and muscular and cardiovascular endurance

We plan according to this because strength and speed are the attributes that take longest to develop. High intensity intervals also confer aerobic benefits of increased muscular and cardiovascular endurance so we don’t need such a large focus on longer runs just yet.

The importance of longer runs is because of increases in running economy. Basically, the more running you do, the body gets more efficient at the movement. Thus, running economy seeks to measure this improvement for how much “effort” it takes to run which is measured in oxygen consumption per distance covered. This does not need to be developed as thoroughly yet, since stride length improvements and decreasing the intensity of running quickly take longer to develop and yield better times.

There is the point at which an athlete starts to improve their times into the advanced and elite range. As these times improve, the law of diminishing returns starts to rear its ugly head until you hit the ceiling over which you get negative returns on effort investment. For example, a runner’s primary focus is improving their running times. As strength increases it is harder to improve to get more strength; similarly, stride lengths will increase as slowly as the strength does. There is a point in time where too much strength will decrease the times of the athlete (because strength and endurance are at the opposite ends of the spectrum). Thus, if such a point occurs then it may be necessary to scale down the strength work to maintenance level, and focus more on other attributes to improve.

Thus, at this point we start scaling down the strength work to maintenance level (usually 1-2 times per week) and start increasing the amount of longer distance running we do to improve running economy and increase muscular and cardiovascular endurance.

For instance, let’s take a look at the training of one of the elite runners of the past, Hicham El Guerrouj (currently holds WR in 1500m, won some 5k golds). Looking at his training cycles which resulted in some world records let’s look at the proportion of work he was doing:

First cycle – 21 days
Training sessions: 35
Strength/power work: 10 = 28.6%
Physical preparation: 2 = 5.8%
Aerobic work (intervals + longer runs): 23 = 65.7%

A relatively huge proportion of strength/power work at 28.6% considering what your average runner does which is 0%.

Second cycle – 21 days
Training sessions: 37
Strength/power work: 6 = 16.2%
Race pace (intervals): 5 = 13.5%
Aerobic work (fast pace + recovery): 70.2%

Still a significant amount of strength/power work + intervals. Aerobic work is up to 70% which is to be expected of a distance runner in 1500m and 5000m.

Third cycle – 21 days
Training sessions: 38
Race pace + speed work (intervals): 8 = 21.1%
Warming up + aerobic (recovery + fast pace): 30 = 78.9%

No strength/power, but increased work with speed and intervals to improve race ability. Still a significant margin at 21%.

This corresponds to what I said earlier. He has a small but significant amount of strength/power work to maintain strength and speed, and the majority of the running tends to focus on intervals + longer recover runs + fast pace work which allow him to improve running economy and muscular and cardiovascular endurance.

My point with looking at all of this work is that he always has a fair amount of interval/speed work or strength/power work in his training. Most of the longer distance runners you and I know that may even be competitive barely have any of these types of training sessions if any at all. This is a huge mistake.

Also, for reference, his slowest “recovery” work listed is 18-19s per 100m (which is the 3:00-3:10 pace over 1km). This is most definitely not LSD. Consider that a “decent” time for 5k is 20 minutes. This corresponds to 24s per 100m. His “recovery” work is 25% faster than a decent 5k time.

In conclusion, like strength training or any other type of sports training, novices/intermediate runners have no business training like the advanced/elite runners. We put novices on linear progression strength training while leaving more complicated periodized work for the elite athletes. The same is true of running as to improve times we have different focuses at different levels of ability.

The amount of strength and speed work needed for an endurance runner is proportional to your ability level. Novices need the most amount of strength and speed work, but as your times decrease you need proportionally less. When you’re elite endurance runner, you’re aiming just to maintain strength and speed, and run a huge amount of miles for the running economy and further gains in muscular and cardiovascular endurance. If I were to structure a novice’s training I would probably start with 30-40% strength/power, 10-20% intervals/speed work, and 50-60% longer runs. As they get more advanced, you can slowly phase down the strength/power work and turn it into more sessions of longer running. Interval distance will also increase to suitable lengths in proportion to the race distance as speed increases.

The above is just a general idea. However, most of the elite endurance runners can run under 11s 100m. If you’re not there you need to be prioritizing your strength/power and speed work to get there at the very least. Then can come the increased focus on longer runs.


1. For extra resources on developing improved sprinting/speed ability go here.

2. Bastardization of speed work such as that which is thrown into CrossFit metabolic conditioning does not really improve speed although you do get muscular and cardiovascular endurance benefits. Throwing them together in this fashion leads to mediocre results as evident by most of the best CFers only getting 18-20 min 5k times (although it’s true they are not aiming for much better results than that). In 2016, CF 5k athletes times are probably down closer to to the 15-18 min range. The focus needs to be specifically on speed work and strength transitioning into longer runs and run specific intervals.

This article was originally published August 19, 2009 on Eat Move Improve. Updated Dec 2016. 

Questions about articles may be addressed to the Overcoming Gravity reddit.

Author: Steven Low

Steven Low, author of Overcoming Gravity: A Systematic Approach to Gymnastics and Bodyweight Strength (Second Edition), is a former gymnast who has performed with and coached the exhibitional gymnastics troupe, Gymkana. Steven has a Bachelor of Science in Biochemistry from the University of Maryland College Park, and his Doctorate of Physical Therapy from the University of Maryland Baltimore. Steven is a Senior trainer for Dragon Door’s Progressive Calisthenics Certification (PCC). He has also spent thousands of hours independently researching the scientific foundations of health, fitness and nutrition and is able to provide many insights into practical care for injuries. His training is varied and intense with a focus on gymnastics, parkour, rock climbing, and sprinting.