By Bryan Dermody
Bryan Dermody, CSCS, is an Assistant Strength and Conditioning Coach for football at the University of Iowa. He is currently working toward his Master’s degree in kinesiology.
Training & Conditioning, 13.6, September 2003, http://www.momentummedia.com/articles/tc/tc1306/bands.htm
Strength and speed are among the most sought-after physical qualities in athletics. Many athletes and coaches have come to believe that strength and speed are independent athletic qualities and should thus be trained separate from each other. These two qualities, however, are intimately related.
Strength has been defined as the ability to produce force, or more accurately, the highest force attained at a given speed of movement. Another important basic point relating to strength is that, according to Newton’s second law of motion, for every action an action equal in force and opposite in direction will occur.
As a result, the amount of force that an athlete is able to apply to the ground will determine how fast he or she can run and how efficiently he or she can change direction (i.e., run laterally). Thus, speed is, in effect, determined by strength. So if one wants to become faster, one simply has to train to become stronger, correct?
While they are related, it is not quite that simple. Athletes do not have the luxury of an abundance of time to recruit what strength levels they do possess. It has been shown that 0.3-0.4 seconds or more are required to reach maximum force levels. Further, during maximum lifts in the traditional squat and deadlift movements, 0.6 seconds elapse before the movement is completed.
These may seem like relatively short periods of time. However, the time available to produce force in athletics is much less. For example, in explosive movements, such as running and jumping, force has to be produced in less than 0.3 seconds. In fact, it is usually closer to 0.1-0.2 seconds. It is critical to athletic success that athletes are able to recruit their strength in a very short period of time. This becomes more apparent the higher the level of play and the greater the speed of the game.
It soon becomes clear that strength is not the sole determinant of optimal force output. The rate of force development (RFD) is much more important than strength alone.
Several different types of strength have been distinguished, among them absolute strength. This type of strength can be defined as the ability to produce force without regard for one’s bodyweight (relative strength), how fast the force is being produced (explosive strength), how fast the external resistance is accelerated from a static position to initiate movement (starting strength), and how fast the external resistance is being accelerated during the beginning of the movement (acceleration strength). Most traditional resistance training programs address absolute strength.
It will seldom be argued that absolute strength cannot aid in the athletic success of the athlete. However, an athlete can possess great strength and still be deficient in the ability to generate force quickly. As the training maturity of the athlete increases, it is RFD rather than absolute strength that becomes the limiting factor in the improvement of performance.
Solving the Problem
The strength and conditioning coach is thus left seeking an effective training method to improve RFD in the athlete. A common solution is to simply move the external resistance as fast as possible. However, this is easier said than done.
The amount of strength that involved muscle(s) can generate during a certain movement is determined, to a large extent, by the joint angles throughout the movement. For example, during the traditional squat and bench press movements, much more force can be generated at the middle to end ranges of motion because of the mechanically advantageous joint angles created.
However, if an athlete were to attempt to accelerate a load through the entire range of motion with sub-maximal weights, injury to the involved joints and/or musculotendinous unit would likely occur. The load has to be decelerated, and we do this naturally when lifting any object.
On the other hand, if a much higher load was used in order to ensure that the motor units were stimulated maximally through the end ranges of motion, the movement would be of only partial range. The joint angles would be at a so-called “mechanical disadvantage” in the early phases of the movement and would not be able to generate enough force to move the load.
A final area that needs to be clarified before a solution to our training dilemma is solved is that of training specificity. It has been said that the more the specific training is, the better the carryover will be to sport performance. Many coaches and athletes erroneously believe that the term “sport-specific” refers to movements in the weightroom that mimic actual sports movements such as tackling and blocking. A distinction must be made between true specificity and mimicking sport tasks.
The goal of training specificity is not to simulate any sporting activity, but rather to adhere to the principle of “dynamic correspondence,” a term first used by Russian sport scientist Yuri Verkhoshansky. According to this principle, the aim of training specificity is to include in the training movement the same biomechanical and motor characteristics that are manifested in the sport task. The following are variables that should be included when considering the specificity of any training movement: type of muscle contraction, movement pattern, velocity and acceleration of movement, RFD, force of contraction, and muscle fiber recruitment. It should be noted that training specificity grows in importance as the training maturity of the athlete increases.
Thus, we are left with the task of finding a training means that will result in an increase in RFD, has a negligible deceleration phase, and meets our criterion of specificity. The answer: variable resistance.
By attaching chains and/or big rubber bands to the barbell during lifting, a situation can be created where the resistance actually increases as the athlete becomes biomechanically stronger through the movement. To illustrate, imagine an athlete performing a back squat with 300 pounds on the bar plus an additional 40 pounds of chain hanging on each side. At the top of the lift the athlete has 380 pounds on his or her back. As the athlete descends, the chains gather onto the ground. Thus, at the bottom of the lift, the athlete has 300 pounds on the bar, and as he or she ascends, the chains will come off of the ground and the resistance will continue to increase as mechanically advantageous joint angles are created.
The same principle applies to bands. The tension in the bands is greatest at the top and least at the bottom of the movement.
As you can see, the problem we faced earlier of dealing with large deceleration phases is solved. In addition, since the resistance increases throughout the movement, the athlete is forced to attempt to move the load fast. (If the athlete attempts to move the resistance without accelerating through the movement, it is likely that he or she will be unable to complete the movement explosively.) Since movement speed is critical when training to increase RFD, our goal is accomplished.
Using bands has another advantage because of the tension they provide. As the athlete descends in a movement, this tension is stored as potential energy in the stretched muscles and tendons. This potential energy is transformed into kinetic energy during the ascent of the movement. Since the bands force the tendons and muscles to store potential energy and quickly transform it to kinetic energy, they decrease the inhibitory mechanisms in the neuromuscular system and lead to increases in the magnitude and speed at which forces are achieved.
Many coaches will argue that plyometrics will accomplish the same goal as training with variable resistance. However, the resistance offered in plyometrics is only the athlete’s bodyweight, while the resistance when maximal power is achieved is much higher. (Maximal power is achieved at 30 percent of maximal isometric strength.) Further, it has been shown that training with heavy resistance, as many athletes do, actually increases the athlete’s ability to achieve maximal power.
Many coaches will also argue that since running is largely a horizontal activity, a movement performed in the vertical plane is not specific to running. Research has demonstrated, however, that the forces that limit sprinting speed are vertical forces, not horizontal ones. As a result, our last training criterion of specificity is met.
How to Use
Chains and bands can be used with a variety of movements. At the University of Iowa, we mainly use them with squats and bench presses, but they can also be used for incline presses, good mornings, and Romanian deadlifts.
In order to set up the chains properly, you need two chain lengths six feet long and a quarter-inch thick, and two chain lengths five feet long and five-eighths-inch thick. The small chain is looped through the ends of the larger chains. Carabiner hooks are also needed to attach the two ends of the small chain and to be able to adjust the length of the entire chain unit. After this, the small chain is draped around the bar before the weight is put on so the large chain hangs toward the ground. When the athlete is standing upright at the beginning of the lift, just enough chain should be on the ground (about two links) so it does not swing as the athlete performs the movement. To set the chains up for the bench press, simply loop the small chain through both ends of the large chain so as to decrease the large chain length by one half.
In order to properly set up the bands, loop the bands under the very bottom of a power rack and put one end through the other one so the band is securely affixed to the power rack. Loop the free end of the band around the bar before you put the weight on. There should always be slight tension in the bands at the bottom of the movement. The bands we use are two inches wide by 20 inches long and offer 20-35 pounds of resistance at the top of the movement. (The band tensions will vary slightly with the height of the athlete.)
Typically, five to eight sets of two to three repetitions are performed with 45-60 seconds rest between sets. The reps are kept low because the nervous system component of the movement is so high when high speed is used. We do not want the neural drive of the fast twitch fibers to be affected by fatigue. However, the rest periods are relatively short because the neuromuscular system recovers faster from movements aimed at increasing rate of force development as opposed to maximal strength movements. We want nervous system excitement to remain high throughout the five to eight sets in order to ensure that the greatest intent to move the bar fast is used with every repetition.
The chain and band resistance is not kept the same for all strength levels, nor is it kept the same for every cycle of variable resistance training. Each strength level has a base resistance and an advanced resistance. If the strength level is such that 1.5 chains of resistance are required on each side of the bar, make sure half of one chain is on the ground in the start position. The same bands are not used for squat and bench simply because of the large difference in range of motion of each movement.
Certain prerequisites should be met before training with variable resistance. At the University of Iowa, athletes must complete 16 weeks of base strength training in a developmental program emphasizing ground-based, three-dimensional, multi-joint movements. Torso training, including torso stabilization, flexion, rotation, and hip extension, should be emphasized during this and all other phases. After the 16-week developmental phase, lower-body strength and torso strength are re-evaluated. Under normal circumstances the athlete then progresses to variable resistance training.
The first eight to 10 weeks of variable resistance training should be done with chains only. The reason for this is that a high degree of torso strength is required to stabilize oneself when using bands. Further, when using chains only, the force of gravity is providing resistance. With bands, however, there is added resistance with the tension in the bands.
This form of training is not the only way to increase an athlete’s RFD. It does, however, have sound scientific backing. Further, we have found great success with it at the University of Iowa.
The author wishes to extend a special thanks to Chris Doyle, Head Football Strength and Conditioning Coach at the University of Iowa, for his valuable mentoring over the past four years.
References for this article can be found on our Web site. Please log onto: www.AthleticSearch.com/bands
Fred Hatfield, PhD, is credited with coining the term “compensatory acceleration” in the United States, also called variable resistance. He used this term to describe a method of training that he postulated would accomplish the goal of increasing the rate of force development of the athlete. According to Hatfield, the athlete must push against a sub-maximal external resistance as hard as possible through the entire range of motion. It sounds simple and effective.
In fact, the intent to move the load may be more important, or just as important, as the actual speed of the load being lifted. In other words, the contraction speed of the muscle(s) involved in the movement must be fast, but the load itself doesn’t necessarily have to move quickly in order to elicit an increase in rate of force development (RFD).
There is, however, a major shortcoming to this methodology. Empirical as well as laboratory findings have proven that when the compensatory acceleration training method is used, a large portion of the movement range is spent decelerating the resistance. If the muscles involved are decelerating the load, the motor units of these muscles, in particular the fast twitch units, are not undergoing the proper training stimulus and thus will not adapt accordingly. The result is that the goal of recruiting strength faster is not accomplished most effectively.
Last year, a study by William Ebben, MS, MSSW, CSCS*D, and Randall Jensen, PhD, FACSM, published in the Journal of Strength and Conditioning Research (Vol. 16, No. 4), evaluated characteristics such as rate of force development (RFD), muscle activation of the quadriceps and hamstrings, and peak force development while using bands and chains. The researchers concluded that squats with chains and bands offer no advantages over traditional barbell squats. However, I believe there were some serious flaws in the design of this study.
First, the amount of chain and band resistance that was used accounted for 10 percent of the total bar weight. This is hardly enough resistance to negate the deceleration phase. The athlete would not be able to accelerate through the entire movement, and thus not receive the training benefit of increased RFD.
Further, the intensity of the load was not listed in the article. It could have been too light or too heavy to achieve the desired training effect.
Finally, the length of the study was one training session. It is extremely unlikely one would see profound results from any method of training after only one training session. The overload from one training session would unlikely be high enough in magnitude to stimulate adaptation within the involved motor units.
Aagaard, P. Training induced changes in neural function. Exercise and Sport Science Review. 31(2): 61-67. 2003.
Behm, David G. Neuromuscular implications and applications of resistance training. Journal of Strength and Conditioning Research. 9(4): 264-274. 1995.
Behm, David G. and Digby G. Sale. Intended rather than actual movement velocity determines velocity-specific training response. Journal of Applied Physiology. 74: 359-368. 1993.
Cronin, John B., P. J. McNair and R. N. Marshall. Force-velocity analysis of strength training techniques and load: Implications for training strategy and research. Journal of Strength and Conditioning Research. 17(1): 148-155. 2003.
Ebben, William P. and Randal L. Jensen. Electromyographic and kinetic analysis of traditional, chain, and elastic band squats. Journal of Strength and Conditioning Research. 16(4): 547-550. 2002.
Elliot, B. C., G. J. Wilson and G. K. Kerr. A biomechanical analysis of the sticking region in the bench press. Medicine and Science in Sports and Exercise. 21(4): 450-462. 1989.
Garhammer, J. A review pf power output studies of Olympic and powerlifting: Methodology, performance, and evaluation tests. Journal of Strength and Conditioning Research. 792): 76-89. 1993.
Giancoli, Douglas C. Physics for Scientists and Engineers. 3rd ed. Upper Saddle River, NJ. Prentice Hall, 2000. p. 80.
Haff, Gregory G., M. Stone, H. S. O’Bryant, E. Harman, C. Dinan, R. Johnson, and K. Han. Force-time dependent characteristics of dynamic and isometric muscle actions. Journal of Strength and Conditioning Research. 11(4): 269-272. 1997.
Hatfield, Fredrick C. Getting the most from your training reps. NSCA Journal. 14(5): 28-29. 1982.
Hatfield, Fredrick C. Power: A Scientific Approach. Chicago, IL. Contemporary Books, 1989. pp. 9-12, 137.
Jones, K, G Hunter, G. Fleisig, R. Escamilla and L Lemak. The effects of compensatory acceleration on upper-body strength and power in collegiate football players. Journal of Strength and Conditioning Research. 13(2): 99-105. 1999.
Knuttgen, Howard, G. and P.V. Komi. Basic considerations for exercise. In: Strength and Power in Sport 4th ed. P. V. Komi ed. Oxford, UK. Blackwell Science, 2003. p. 6.
Linnamo, V., K. Hakkinen and P.V. Komi. Neuromuscular fatigue and recovery in maximal compared to explosive strength loading. European Journal of Applied Physiology. 77: 176-181. 1998.
McBride, Jeffrey M., T. Triplett-McBride, A. Davie and R. U. Newton. A comparison of strength and power characteristics between power lifters, Olympic lifters, and sprinters. Journal of Strength and Conditioning Research. 13(1): 58-66. 1999.
McGinnis, Peter M. Biomechanics of Sport and Exercise. Champaign, IL. Human Kinetics, 1999. p. 358.
Newton, Robert U. and William Kraemer. Developing explosive muscular power: Implications for a mixed methods approach. Journal of Strength and Conditioning. 16(5): 20-31. 1994.
Newton, Robert U., W. J. Kraemer, K. Hakkinen, B. J. Humphries and A. J. Murphy. Kinematics, kinetics, and muscle activation during explosive upper body movements: implications for power development. Journal of Applied Biomechanics. 12: 31-43. 1996.
Plisk, Steven S. Where the weight room meets the classroom. Coach and Athletic Director. August: 15-20. 2000.
Sale, Digby G. Neural adaptation to strength training. In: strength and Power in Sport. 4th ed. P.V. Komi ed. Oxford, UK. Blackwell Science, 2003. pp. 296-306.
Siff, Mel C. and Yuri V. Verkoshansky. Supertraining. Denver, CO. Supertraining International, 1999. pp. 1-3, 88-90.
Verkoshansky, Yuri V. Fundamental of Special Strength Training in Sport. Livonia, MI. Sportivny Press, 1986. pp. 25-28, 181.
Verkoshansky, Yuri V. Principles of training high level track and field athletes. Soviet Sports Review. M. Yessis ed. 17(1): 41-44. 1982.
Weyend, P. G., D. B. Sternlight, M. J. Bellizi and S. Wright. Faster top running speeds are achieved with greater ground force, not more rapid leg movements. Journal of Applied Physiology. 89: 1991-1999. 2000.
Wilson, Greg J., R. U. Newton, A. J. Murphy and B. J. Humphries. The optimal training load for the development of dynamic athletic performance. Medicine and Science in Sports and Exercise. 25(11); 1279-1285. 1993.
Young, Warren. Training for speed/strength: Heavy vs. light loads. NSCA Journal. 15(5): 34-42. 1993.
Zatsiorsky, Valdimir M. Biomechanics of strength and strength training. In: Strength and Power in Sport. 4th ed. P. V. Komi ed. Oxford, UK. Blackwell Science, 2003. pp. 440-441.
Zatsiorsky, Vladimir M. Science and Practice of Strength Training. Champaign, IL. Human Kinetics, 1995. 35-37, 202-205.