There have been a large number of people lately who have been using the terms "strength-speed" and "speed-strength" interchangeably. Unfortunately, this is incorrect.  At its base, strength-speed means strength in conditions of speed. Speed-strength, on the other hand, means speed in conditions of strength (Ajan, 1988; Roman, 1986). What this essentially means is that strength-speed means that you move a heavy(er) weight as fast as you can. Typically, this is around 60% of a 1RM, and the bar moves at a specific velocity of .8-1.0m/s. In turn, speed-strength essentially means that you are trying to move as fast as you can, but your are moving a light(er) weight. Typically, this is around 25-40% of a 1RM, and the bar moves at 1.1-1.5m/s. Understanding these velocities and the difference between the two leads to specificity, which will be brought back into the conversation a little later on.

Strength-speed and speed-strength are two independent traits that can be developed separately. Might doing strength-speed work improve speed-strength? The answer is yes, but primarily only in the early onset of training. Tudor Bompa stated that all strengths relate back to absolute strength, so getting stronger will improve all other traits (Bompa, 1963). And this is true, at least for a while. In their studies, Jacobson et al found that improvements in power do not continue simply with increases in absolute strength, and they usually level off after the second year of training.

This misunderstanding of the terms has also led to a lot of debate between different sects of strength and conditioning coaches. However, think of it this way: if the terms were interchangeable, then there wouldn't be a need to Olympic lift. It would be absolutely pointless to teach the athletes these complex movements if squatting fast developed the same trait.

Realize, though, that these separate traits have to be trained at the appropriate velocity. Whenever I speak on Velocity-Based Training, I always give the example of my project for my regression statistics class. I had to write a 25-page paper and do it on something that I knew and enjoyed. Thus, I chose to do it on how cleans were related to the vertical jump. Cleans are done for explosive power; the vertical jump is an expression of explosive power. Ergo, improvements in cleans should relate to improvements in the vertical jump. However, this is not what I found.  Much to my surprise, there was no relationship between cleans and the vertical jump when running the data. I was so taken aback by this that I scheduled time with the professor to ensure that I ran the data correctly. It turns out that I had, and I was dumbfounded.

I brought this information to my boss, Pat Ivey, and we began to discuss what could be going on. There could be many confounding variables, but it seemed most logical to assume that we got caught up in trying to increase the simple weight on the clean and therefore had lost the purpose of the movement—developing speed strength. The first time we measured the velocity of the bar on our cleans, we found that they were moving at .6m/s. However, for our athletes, the bar should have been moving at a minimum of 1.4m/s (Ajan, 1988; Roman, 1986; Verkhoshansky, 1982). So, by simply using the specific adaptation of imposed demands (SAID principle), we were imposing the demand of a slower, non-explosive strength and were expecting the adaptation of explosive strength. Obviously, this is not how the principle works, and this is why we were seeing what we did. Thus, when we altered our hang cleans in order to achieve a certain velocity, they did, in fact, end up having a relationship to the vertical jump. It became the third relationship, but it still did have a significant impact on it. (A decrease in body composition being first the first relationship, an increase in squat being second, and then the clean being third).

There has been much confusion because of the inability to differentiate the two traits mathematically. Now, with the availability of accelerometers, linear position transducers, and high speed 3D cameras, we are now able to capture these velocities. So, by utilizing the Soviets' interpretations of the data, we can deduce the velocities at which we need to be training in order to invoke the adaptations we desire.

Recently, researchers from Belgium have independently agreed with and supported this former soviet concept of the two separate traits. Jidovtseff et al found that there were two separate and more explosive strengths on the bench press that they referred to as "power-velocity" and "strength-power" (Jidovtseff, Quièvre, Hanon, & Crielaard, 2009). Interestingly enough, they found that power-velocity occurred when moving 25-54% of their 1RM as fast as possible, which led to velocities of about 1.4 m/s to about 1.0 m/s. Also, strength-power was found to be developed from 54-82% of their 1RM when moved as fast as possible, and it related to velocities of .8 m/s down to about .7 m/s. These percentages and velocities are nearly perfect with the Soviets', who did their research on squat. Research by Jandacka also confirmed the Belgium researchers' findings for the two separate traits that need to be developed by two separate means (Jandačka & Beremlijski, 2011).

In realizing the specificity of velocities, it is important to note that some things must be realized:

  1. Olympic lifts, when done properly, do an excellent job of developing speed-strength.
  2. The velocity of the movement is just as important as the movement. Can you do Olympic lifts too slow and not develop speed-strength? Absolutely. I for one have done it. Can you alter squats and other exercises to develop speed-strength? Absolutely.

In closing, here are two points that I want to make:

  1. Strength-speed and speed-strength are different traits.
  2. It is the quantity of the quality of the work (which can be determined by whether it meets what is desired by the SAID principle) that matters, not just the quantity. It does not matter if you do a ton of Olympic lifts if they’re too slow for optimal rate of force development. You won’t be increasing explosive abilities...all you are doing is wasting time.

To end, I’d like to close with a quote from John Wooden, “If you don’t have the time to do it right, when will you have the time to do it over?”

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References

  • Ajan, T., Baroga, Lazar. (1988). Weightlifting:  Fitness for All Sports (First ed.). Budapest, Hungary: International Weightlifint Federation.
  • Bompa, T. (1963). Periodization:  Theory and Methodolgoy of Training (First ed.): Human Kinetics.
  • Jandačka, D., & Beremlijski, P. (2011). Determination of strength exercise intensities based on the load-power-velocity relationship. Journal of Human Kinetics, 28(1), 33-44.
  • Jidovtseff, B., Quièvre, J., Hanon, C., & Crielaard, J. M. (2009). Inertial muscular profiles allow a more accurate training loads definition. Les profils musculaires inertiels permettent une définition plus précise des charges d'entraînement, 24(2), 91-96.
  • Roman, R. A. (1986). The Training of the Weightlifter (A. Charniga, Trans. 1 ed.). Moscow: Sportivny Press.
  • Verkhoshansky, V. (1982). The Fundamentals of Special-Strengths Training: Sportivny Press.