VELOCITY-BASED RESISTANCE TRAINING (VBRT)

In a previous post, we explained what the strength training variables were. Broadly speaking, we remembered that these were volume, intensity, frequency, density, order of exercises, etc. Correctly managing these variables, as well as accurately quantifying the dose-response, is fundamental for any training prescription (Wernbom, Augustsson, & Thomeé, 2007). In this entry, we will focus on what we consider to be the most important variable in strength training: intensity. This variable is essential and the one that most determines the criterion of specificity in any sport discipline, as well as being the one that most influences the adaptations produced by training (Kraemer & Fleck, 2007).

Traditionally, intensity has been quantified around the percentage of maximum repetition (%1RM), or around the maximum number of repetitions that the subject is able to perform with that load (e.g. 6RM, 10RM...). In both cases, higher intensities are related to higher weights and fewer repetitions, as well as lower execution speed. Other authors have relied on power to quantify intensity, which is the product of force and speed (Baker, 2001). However, if we use power to quantify the intensity of our training, we must bear in mind that factors such as the type of exercise or the experience or level of the subjects will influence it (Kawamori & Haff, 2004).

DSC09705 by Sean Smith in. CC0 1.0

Currently, new trends indicate that the way to follow in controlling the intensity of training is by way of controlling the speed of execution. In the literature we find the name "Velocity-Based Resistance Training" (VBRT), and has meant a radical change in the way of prescribing, controlling and programming strength training. The theoretical basis of this method of control and programming of training is based on the force-velocity curve and its relationship with the load, which indicates that the highest loads move at slower peak and medium speeds, while the lowest loads move at faster speeds (L Sánchez-Medina, González-Badillo, Pérez, & Pallarés, 2014). In addition, a variety of studies by the same research group have found very high relationships between the speed of the fastest repetition of the series (usually the first or second repetition) and the relative intensity of that load on the subject (%RM) (González-Badillo & Sánchez-Medina, 2010; L Sánchez-Medina et al., 2014; Luis Sánchez-Medina & González-Badillo, 2009; Luis Sánchez-Medina, Pallarés, Pérez, Morán-Navarro, & González-Badillo, 2017). In other words, if we were able to measure the maximum speed of the first or second repetition of the series, it would be possible to determine whether the load used represents the previously programmed effort (%RM) at that exact moment, and for that exercise, as well as its 1RM on that particular day (González-Badillo, Yáñez-García, Mora-Custodio, & Rodríguez-Rosell, 2017). In addition, it is known that "intra-series velocity loss" is a more than reliable indicator for the control of neuromuscular fatigue, so the usefulness of this measure is very relevant (Pareja-Blanco et al., 2017; Luis Sánchez-Medina & González-Badillo, 2009).

After having explained some of the benefits of speed measurement in prescription and control training, we consider it appropriate to mention the most commonly used speed of execution measurement methods. Traditionally, the first measurement systems were very archaic and impractical, although little by little they became more professional and provided more information and accuracy at a lower cost. The pioneering elements were some as the photoelectric cells, the Ergopower and The Isocontrol, although at present they have been surpassed by more current technologies. Sometimes, the fact that the technology is more current does not mean that it is more precise. In fact, there are currently technologies that have different limitations when it comes to evaluating the speed of execution, but due to their simplicity and economy they are much more widespread than more expensive and precise options.

To summarise the different existing technologies, we can mention the following: force dynamometric platforms, speed and position transducers, accelerometers and video-analysis. In all of them, due to the mathematical calculation required for the estimation of the results, a certain error will be dragged along, in addition to the fact that each one of these technologies has certain limitations. Nor do we consider it opportune to assess each of the technologies, but as a conclusion, we can say that not all have the same validity and usefulness, as some do not value fundamental parameters such as average propulsive speed or loss of speed in the same set. On the other hand, they present certain advantages that justify their use, such as low cost or good portability. Therefore, we must be critical of the choice of one or another technology, being aware of the limitations of each one, as it would be a problem to try to interpret the data without taking into account this limiting aspect. At least, the expansion of these cheap and practical devices (although they are not as reliable as we would like), has made the measurement of speed in strength training known to the public, gradually expanding its field of action.

See you in the next post. 

May the force be with you!

References

Baker, D. (2001). Comparison of upper-body strength and power between professional and college-aged rugby league players. Journal of Strength and Conditioning Research, 15(1), 30–35. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/11708703
González-Badillo, J. J., & Sánchez-Medina, L. (2010). Movement Velocity as a Measure of Loading Intensity in Resistance Training, 347–352.

González-Badillo, J. J., Yáñez-García, J. M., Mora-Custodio, R., & Rodríguez-Rosell, D. (2017). Velocity Loss as a Variable for Monitoring Resistance Exercise. Int J Sports Med, 38(3), 217–225. https://doi.org/http://dx.doi.org/10.1055/s-0042-120324

Kawamori, N., & Haff, G. G. (2004). The Optimal Training Load for the Development of Muscular Power. The Journal of Strength and Conditioning Research, 18(3), 675. https://doi.org/10.1519/1533-4287(2004)18<675:TOTLFT>2.0.CO;2

Kraemer, W. J., & Fleck, S. J. (2007). Optimizing strength training : designing nonlinear periodization workouts. Champaign, IL : Human Kinetics. Retrieved from https://ua.on.worldcat.org/search?queryString=no%3A+87764289#/oclc/87764289

Pareja-Blanco, F., Rodríguez-Rosell, D., Sánchez-Medina, L., Sanchis-Moysi, J., Dorado, C., Mora-Custodio, R., … González-Badillo, J. J. (2017). Effects of velocity loss during resistance training on athletic performance, strength gains and muscle adaptations. Scandinavian Journal of Medicine and Science in Sports, 27(7), 724–735. https://doi.org/10.1111/sms.12678

Sánchez-Medina, L., & González-Badillo, J. J. (2009). Velocity Loss as an Indicator of neuromuscular fatigue during resistance training. Med. Sci. Sport., (April), 142–152. https://doi.org/10.1249/MSS.ObO

Sánchez-Medina, L., González-Badillo, J. J., Pérez, C. E., & Pallarés, J. G. (2014). Velocity- and power-load relationships of the bench pull vsBench press exercises. International Journal of Sports Medicine, 35(3), 209–216. https://doi.org/10.1055/s-0033-1351252

Sánchez-Medina, L., Pallarés, J. G., Pérez, C. E., Morán-Navarro, R., & González-Badillo, J. J. (2017). Estimation of Relative Load From Bar Velocity in the Full Back Squat Exercise. Sports Medicine International Open, 1(2), E80–E88. https://doi.org/10.1055/s-0043-102933

Wernbom, M., Augustsson, J., & Thomeé, R. (2007). The Influence of Frequency, Intensity, Volume and Mode of Strength Training on Whole Muscle Cross-Sectional Area in Humans. Sports Medicine, 37(3), 225–264. https://doi.org/10.2165/00007256-200737030-00004