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Horizontal Jumping 101By Cameron Gary Running and jumping (along with lifting and throwing) are the most fundamental of human athletic movements. The Olympic Motto of "Citius, Altius, Fortius" (faster, higher, stronger) illustrates the applicability of these basic performance attributes. However, to avoid digressing into a history lesson, suffice it to say that in sprint/jump training we strive to develop all athletic performance attributes to some extent. What could be more basic to sport than running and jumping? I guess that is why the sport of Track & Field is called “Athletics” in most other parts of the world. Running and jumping are two very closely related movements/disciplines. In a later installment I will specifically focus on that relationship. However, in this article we’ll look at the basics as they relate to jumping in general and horizontal jumping (long jump and triple jump) in particular. I hope this article will provide some insights into these basic movements so you can help your athletes develop their athleticism to their highest levels. I understand the readers of this article represent various levels of experience and technical sophistication. Although I have a reasonable technical understanding of the jumps, I am a “plain speaking” kind of fellow. I don’t claim to be a biomechanics expert (as I most certainly am not). I am just a guy who has practiced/coached these events for a little while. I’ll progress through the technical aspects from the most basic to the more advanced levels. Please forgive me if the basics review does not excite some of you. But I want to make sure this information is palatable to everyone – rather than just a select few. That being said; I only teach what I know. Hopefully, I know what I teach. The Basics Jumping is simply a fast, coordinated extension of the hips, knee(s) and ankle(s) in order to quickly push one’s center of mass away from the ground far enough that the feet break contact with the ground (“foot release”). This three-phased extension is sometimes called a “triple-extension” movement, or as noted mechanics expert Geoff Dyson says, a "summation of forces" (see inset). It is important to understand that one needs all three forces working together in order to have an efficient jumping effect! Any doubts? Try jumping without extending the feet (or knees, etc.) and it will be quite evident how limited your jumping will be. Of course there are other more complex dynamics (countermovements, stretch-shortening cycles, etc.) to be accounted for; but basically the “tripleextension ” is the key. One can attempt all the advanced skills one wishes; but if one does not triple-extend; one will not jump!
Force
Gravity
Center of Mass (COM)
Speed and Velocity
Acceleration
Inertia
Momentum
Impulse
Counter- Movement Jumping For our purposes, we are concerned primarily with counter-movement jumping. In fact, we take this type of jumping to a higher level by incorporating training methods that increase the eccentric or "loading" phase. The hopeful result would then be to increase the subsequent response in order to produce a stronger concentric or “explosive” reaction. I will explain this concept in more detail below, but this is the type of jumping that is most useful for sprint/jump athletes. It is also the reason why counter-movement weight lifting exercises such as the Power Clean, Jerks, and Snatch are productive. Plyometric/Stretch-Shortening Cycle (SSC) Now for the fun stuff! The SSC is the ballistic-reactive process that occurs when one causes a shortening muscle to lengthen. This is analogous to a rubber band pulled between two fingers – although it is lengthening, it is always “trying” to shorten. I will use the analogy of a rubber ball bouncing when dropped onto a hard floor to explain the SSC, as it is most applicable to sprinting and jumping. This is how it works… When the ball is dropped (or projected, rolled, etc.) force is applied to it to cause it to move. The ball has mass and velocity, thus it carries momentum. As long as the ball is moving it carries kinetic energy (residual force applied for it to continue to move). In this case, gravity is applying the force. These opposing forces cause the ball to change shape and expand outward in order to accommodate the energy moving within the confines of the ball’s outer layer. This "extra" kinetic energy is briefly stored within the ball. This is analogous to the way a polevaulter’s pole bends upon striking the box (keep this in mind). Of course the ball immediately exerts an opposing force to resume its normal shape. The contained energy is forced back toward the opposite end where there is the least resistance (top of the ball). As nothing other than gravity opposes this energy transfer, the ball is projected (or bounced) upward. You are probably asking, “What does this have to do with sprinting/jumping?” Read on, grasshopper, read on… When the SSC is utilized in training the sprints and jumps, we train to become a "rubber ball", more or less. We cause the shortening muscle to quickly lengthen during the eccentric phase in hopes of eliciting a more powerful impulse and resultant concentric muscular contraction. This intense "Stretch-Reflex" response is very fast and powerful relative to the size of the involved muscle. We endeavor to make ourselves more like a “super” ball (remember those?) so we can “bounce” even higher/faster. This explains why one can run faster on asphalt than on soft sand while expending the same amount of effort. The former simply returns more energy than the latter. Strength vs. Power Maximum jumping height/distance DOES NOT come from an excessive bending of the knees or "pressing" harder into the ground. “Pressing” is simply TOO SLOW! To jump higher/farther, you have to jump FASTER! The jumps and sprints are "active" movements. We want to increase absolute strength, but not at the expense of dynamic jumping power – especially “impulse”. Absolute strength is about quantity of force. Dynamic “power” is about quality of force. As power is a function of strength versus time, we have two paths to take; 1) increase the amount of strength we can exert within a given amount of time, or 2) utilize the available strength we possess as quickly as possible. This is an individual decision that depends upon the athlete’s goals and physical capabilities. But the bottom line is that we must seek to maximize the qualities of force. We must never forget this. There is one possible exception to this concept - the stationary sprint start. The dynamics are a little different because the athlete starts from a static position. In that case, the athlete needs to generate a large quantity of force into the blocks, and then the ground in order to overcome inertia and start the body moving down the track. This is why the development of sprint power should be first in your order of business. One can’t maintain speed one hasn’t developed it in the first place. Early in the race, the proportion of time spent applying force into the ground is relatively long (higher strength requirement). But after the body is moving and maximal velocities are approached, the key to sustaining one’s momentum is to maximize the impulse imparted into the ground. One does this by causing higher ground-reaction forces (“striking” the ground harder and faster). The athlete does not try to run faster by “pressing” into the ground. Instead, the athlete strives to generate a quicker "bouncing" impulse at the correct angle of projection for sprinting (using correct sprint mechanics). Never forget that sprinting is a series of continuous jumps! REFERENCES: AAF. 2007. AAF Track and Field Coaching Manual. Los Angeles, CA; Amateur Athletic Foundation of Los Angeles Bullard, E. and Knuth, L. 1977. Triple Jump Encyclopedia. Pasadena, CA; The Athletic Press Chu, D. 1998. Jumping into Plyometrics. Champaign, IL; Human Kinetics Dintiman, G. and Ward, B. 2003. Sports Speed (3rd Edition). Champaign, IL; Human Kinetics Dyson, Geoffrey. 1986. The Mechanics of Athletics (8th Edition). New York, NY: Holmes & Meier Publishers Ecker, T. 1985. Basic Track and Field Biomechanics. Los Altos, CA; Track & Field News, Inc. Gambetta, V. 2007. Athletic Development. Champaign, IL; Human Kinetics Jacoby, E. and Fraley, B. 1995. The Complete Book of Jumps. Champaign, IL; Human Kinetics Cissik, J. 2003. Strength Training for Track and Field. Mountain View, CA; Tafnews Press Tafnews Press/Jarver. J. 2000. The Jumps; Contemporary Theory Technique and Training (5TH Edition).Mountain View, CA; Tafnews Press United States Track and Field Coaching Education. 2005. Level 1 Curriculum. Indianapolis, IN; USA Track & Field, Inc. Recommended Athletes' Acceleration Products About The Author: Cameron is a long-time horizontal jump coach from the San Diego area. He is currently the jump coach at Monte Vista High School in Spring Valley, CA. Cameron formerly coached the horizontal jumps at Helix High School in La Mesa, CA from 1980-81 and 2004-2006; as well as at San Diego State University from 1985-87. In the past four years, Cameron has qualified three different athletes for the California State championships in the horizontal jumps. Cameron also coached the California State JUCO Champion in 2005. The previous year, this athlete also finished 4th in triple jump at the National Junior Olympics. Cameron currently serves as an advisor and consultant to numerous high school, collegiate and elite athletes and coaches throughout the country. Cameron also is a coaching clinic presenter for the Amateur Athletic Foundation of Los Angeles (now called LA84). LA84 is an organization subsidized by proceeds from the 184 Olympics, whose mission is to provide coaching education opportunities to youth, high school and collegiate coaches throughout Southern California. Cameron can count among his endorsers Arnie Robinson (1976 Olympic Long Jump Champion), John Tansley (worldrenowned jump coach) and Larry Knuth (another world renowned jump coach and author of the “Triple Jump Encyclopedia”). During his competitive days, Cameron was standout long jumper and triple jumper at Helix High school. While at Helix in 1978, Cameron broke the Conference meet record in the Long Jump (23’4.5”) that had previously stood for 15 years. He went on to San Diego State University where he broke the Triple Jump school record in 1983 (53’ 2.75"). Cameron was the Western Athletic Conference Triple Jump champion that year and he also qualified for the NCAA Championships. Cameron subsequently qualified for the United States National Championships in 1983, 84 and 85, as well as the United States Olympic Trials in 1984. Since 1985, Cameron has worked as a law enforcement officer in Southern California. He was the California Police Olympics (Now the Western States Police & Fire Games) Champion in the Long Jump and Triple Jump in 1989, 90, 91, 92, and 93. Cameron was also the World Police and Fire Games champion in the Long Jump and Triple Jump in 1989. Cameron is still the Western States Police & Fire Games meet record holder in the Triple Jump (50’ 2" from 1989).
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