Since we got Gym Aware Power Tool system last year for the purpose of tracking power output in countermovement squat jump to estimate neuromuscular fatigue (see great summary by Kristie-Lee Taylor) I have been fascinated by with the simplicity and power of its use.
I started measuring velocity and power with most of the lifts and with recent acquire of Gym Aware Pro Online it made it a lot quicker, reliable and easier.
Researching behind LPT reliability, validity and its use I came across couple of research papers regarding assessment of 1RM by using load-velocity relationship of a given movement (e.g. squats, bench press). Reading those motivated me to do my own small research which you can read HERE.
Eventually I started using the similar approach with my squad (Hammarby IF) to get some insights where is their squat strength going without testing 1RM directly or tiring them with reps-to-failure method (at least for legs – we do reps-till-technical-failure in bench and pull-ups with and without external weight). I think this approach (i.e. load-velocity relationship) provides numerous advantages and it could be used in daily training for monitoring adaptation (tracking what is happening with your estimated 1RM over training block without actually testing it) or programming of the workouts. The velocity of movement will impact the training stimulus and subsequent the adaptations to training. It has been suggested, therefore, that athletes should try to perform exercises “explosively” at a velocity allowed by the resistance used in a volitional manner. Training at a specific velocity improves the application of force and maximum rate of force development mainly at that velocity, so that less effective training effect will occur if training velocity deviates from the specific trained velocity
Reading more about it I came across one group of authors that provided tremendous quality and practical insights when it comes to velocity-based strength training.
| IZQUIERDO M, HAKKINEN K, GONZALEZ-BADILLO JJ, IBAÑEZ J, GOROSTIAGA E. (2002). Effects of long-term training specificity on maximal strength and power of the upper and lower extremity muscles in athletes from different sports events. European Journal of Applied Physiology 87: 264-271. IZQUIERDO M, GONZALEZ-BADILLO JJ, HÄKKINEN K, IBAÑEZ J, KRAEMER WJ, ALTADILL A, ESLAVA J, GOROSTIAGA EM. (2006). Effect of loading on unintentional lifting velocity declines during single sets of repetitions to failure during upper and lower extremity muscle actions. International Journal of Sports Medicine. Int J Sports Med ; 27: 718–724 JUAN J. GONZÁLEZ-BADILLO, MÁRIO C. MARQUES, LUIS SÁNCHEZ-MEDINA. The Importance of Movement Velocity as a Measure to Control Resistance Training Intensity. Journal of Human Kinetics Special Issue 2011, 15-19 SANCHEZ-MEDINA, L., AND J. J. GONZALEZ-BADILLO. Velocity Loss as an Indicator of Neuromuscular Fatigue during Resistance Training. Med. Sci. Sports Exerc., Vol. 43, No. 9, pp. 1725–1734, 2011 J. J. GONZÁLEZ-BADILLO , L. SÁNCHEZ-MEDINA. Movement Velocity as a Measure of Loading Intensity in Resistance Training. Int J Sports Med 2010; 31: 347 – 352 L. SANCHEZ-MEDINA, C. E. PEREZ , J. J. GONZALEZ-BADILLO. Importance of the Propulsive Phase in Strength Assessment. Int J Sports Med 2010; 31: 123 – 129 |
So I decided to contact one of the authors and pick his brain regarding this method of strength training.
Mladen: Mario, thank you very much for taking the time to do this interview. Can you please share some info regarding yourself and your research group? How did you come to the idea to study movement velocity in strength training?
Mario: The ability of the neuromuscular system to produce maximal power output appears to be critical in many sports such as sprinting, jumping or throwing, sports that require optimal combinations of muscle strength and speed to maximize athletic performance. In the classical concentric force-velocity curve the amount of muscle tension increases with decrease in velocity, reaching the maximal tension in the isometric (i.e. 0 velocity) condition.
Under these circumstances maximal power output has been defined to occur at a shortening velocity of approximately 0.3 of the maximal shortening velocity, at a force level of 30% of maximal isometric force and/or between loads of 30%–45% of the one repetition maximum (1RM) (Kaneko et al. 1983; Izquierdo et al 2002 and 2006).
Previous studies have examined the relationship between maximal power output and load in isolated bundles of muscle fibers (Hill 1938) or in explosive movements involving upper or lower body muscle groups such as vertical jumping (Bosco and Komi 1980) or bench-press throws (Newton et al. 1997). However, there is a paucity of data on maximal strength and power of upper and lower extremities muscles in sports activities requiring different levels of strength and power, such as handball, road cycling, middle distance running and Olympic weightlifting. It is likely that the load-velocity and load-power relationships may vary between the different muscle groups, for example, in relation to fibre type distribution, different usage in sport-specific activities and/or biomechanical characteristics of the open and close upper/lower kinetic chains.
Classically, strength training programs have been prescribed according to a percentage of the individual maximal strength (i.e. 1RM). However, velocity-specific increases have been shown with strength training programs using different speeds of movement (Behm and Sale 1993). Therefore, it would be of interest to determine force/velocity and power/velocity relationships so that athletes perform training exercises at specific load and/or velocity that would be more similar to the conditions of muscle performance required in the actual competitive movement (Izquierdo et al. 2002).
Coaches and researchers in the field of resistance training attempt to identify the proper handling of training variables to determine the training stimulus that maximizes performance enhancement. One variable that is less considered when designing programs to optimize athletic performance is movement velocity. Classically, the choice of the load should impact the velocity of the movement but most of the data examining this phenomenon have been obtained with isokinetic exercise. The velocity of movement will impact the training stimulus and subsequent the adaptations to training. It has been suggested, therefore, that athletes should try to perform exercises “explosively” at a velocity allowed by the resistance used in a volitional manner. Training at a specific velocity improves the application of force and maximum rate of force development mainly at that velocity, so that less effective training effect will occur if training velocity deviates from the specific trained velocity.
In 2006 one of my Colleagues (Dr. Mikel Izquierdo from the Public Unviersity of Navarra, Spain) reported that for a given muscle action (bench press or parallel squat), the pattern of decline in the relative average velocity achieved during each repetition (expressed as a percentage of the initial value) and the relative number of repetitions performed (expressed as a percentage of the total number of repetitions performed) was the same with all percentages of 1RM tested. However, relative average velocity decreased at a greater rate in bench press than in parallel squat performance. Conceptually, this would indicate that for loads ranging from 60% to 75% of 1RM, one may predict the pattern of velocity decrease for a given exercise, so that a minimum repetition threshold to ensure maximal speed performance would be determined (Izquierdo et al 2006).
It was showed that the velocity that elicited the maximal power in the lower extremities was lower (» 0.75 m·s-1) than that occurring in the upper extremities (» 1 m·s-1). It is not known why the velocity and the percentage of 1RM that elicits maximal power are different between the upper and lower extremity actions. Such findings are not uncommon since similar results have also been reported during traditional lifts (e.g. bench-press or squat) in young (Cronin et al. 2000; Rahmani et al. 2001; Bosco et al. 1995), middle-aged and older men (Izquierdo et al. 1999).
A possible explanation for these differences observed between the upper and lower extremities may be associated with the extremity-related differences in maximal strength, type of training, muscle cross-section area, fibre-type distribution (Lexell et al. 1983), muscle mechanics (i.e. length and muscle pennation angle) as well as functional differences according to the joint position and geometry of the joints and levers (Gu¨ lch 1994). This type of information on different muscle groups and various actions may also be useful to create optimal strength and/or power training programs for sports with different levels of strength and power demands.
Mladen: What are the differences in load-velocity profiles between upper-lower movements (e.g. squats vs. bench press) or explosive movements like clean, snatch, jump squats or bench throws? What would be their 1RM velocities on average and how do velocities at certain %1RM relate to it (velocity at 1RM)? How does the inclusion or removal of stretch-shortening cycle affect the load-velocity profile (e.g. pause squat or bounce squats)?
Mario: Yes. My Colleague, Professor Mikel Izquierdo From the Public University of Navarra (Spain) showed that, for a given muscle action (bench press or parallel squat), the pattern of decline in the relative average velocity achieved during each repetition (expressed as a percentage of the initial value) and the relative number of repetitions performed (expressed as a percentage of the total number of repetitions performed) was the same with all percentages of 1RM tested. However, relative average velocity decreased at a greater rate in bench press than in parallel squat performance. Conceptually, this would indicate that for loads ranging from 60% to 75% of 1RM, one may predict the pattern of velocity decrease for a given exercise, so that a minimum repetition threshold to ensure maximal speed performance would be determined A different pattern of velocity declines in relative average velocity was observed when performing repetitions at different intensities between upper and lower extremity muscle actions. For all intensities tested, the average repetition velocity decreased at a greater rate in bench press than in parallel squat performance, so that in bench press performance the significant declines observed in the average repetition velocity (expressed as a percentage of the average velocity achieved during the initial repetition) occurred when the number of repetitions was over 34% of the total number of repetitions performed, whereas in parallel squat it was over 48%. In addition, it was interesting to observe that the velocity attained during the last repetition performed during the sets at 75%, 70%, 65% and 60% of 1RM was significantly higher in half squat than in bench press performance (Izquierdo et al 2006)
Mladen: You showed that velocity loss during a set is related to neuromuscular fatigue of the workout. Are there any published or unpublished data on the relationship of velocity loss during a set with adaptation seen over a training block? I know of one study that did just that. What are your opinions on the GREAT results of velocity based group? What are your thoughts on training to failure?
Mario: Yes. As I mentioned above recent studies from Izquierdo and colleagues showed neuromuscular fatigue related to repetitions to failure. (# IZQUIERDO M, IBAÑEZ J, GONZALEZ-BADIILLO JJ, HÄKKINEN K, RATAMESS NA, KRAEMER WJ, FRENCH DN, ESLAVA J, ALTADILL A, ASIAIN X, GOROSTIAGA EM. (2006). Differential effects of strength training leading to failure versus not to failure on hormonal responses, strength and muscle power gains. Journal of Applied Physiology. May;100(5):1647-56.) It was showed that after the 11-wk training period (from T0 to T2), 1) similar gains in bench press 1RM, parallel squat 1RM, muscle power output of the arm and leg extensor muscles, and maximal number of repetitions performed during parallel squat were observed between Repetition to failure (RF) vs. NON repetition to failure approach (NRF) and NRF; and 2) the RF group experienced larger gains in the maximal number of repetitions performed during the bench press. During the peaking phase (from T2 to T3), 3) larger gains in muscle power output of the lower extremity were observed after the NRF training approach, and 4) larger gains were found in the maximal number of repetitions performed during the bench press after RF training approach (Izquierdo et al. J Appl Physiol 2006)
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