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Table 1Foot contacts based on season and skill —— depends on sport ———low–moderateTable 24-square plyo-formation and work volume1, 2 10 reps (2 foot contacts each rep, or 20 foot contacts per set)2, 3 10 reps (20 foot contacts per set)1, 2, 3 10 reps (1 rep 3 foot contacts, or 30 foot contacts per set)4, 3, 2 10 reps (1 rep 3 foot contacts, or 30 foot contacts per set)2, 1, 3, 4 10 reps (1 rep 4 foot contacts, or 40 foot contacts per set)Note: 1 set of each exercise above 140 foot contacts, 2 sets 280 foot contacts.Table 1 adjusts work volume (total footcontacts) and intensity based on seasonal periods and an individual’s readinessfor plyometrics.The recommended volume of specificjumps in any one session will vary withintensity and each workout’s objectives.Table 1 shows how work volume shouldvary for beginning, intermediate, andadvanced workouts (2). For example, abeginner in a workout during the offseason could complete 60–100 foot contacts of low-intensity exercises, while theintermediate exerciser might be able todo 120–200 foot contacts in an off-season workout. With low-intensity jumptraining, the work volume accumulatesquickly. Note that an athlete performing2 sets of each of the exercises in Table 2will complete 280 foot contacts in 1workout using the 4-square formation(please refer to Figure 4 for an illustration of the exercise).It is important to consider the cumulative effect on work volume when combining low- and high-intensity exercisesduring preseason workouts for both intermediate and advanced level athletes.14If an athlete at either level has a scheduled plyometric workout that includes300 total foot contacts, the above example of 280 foot contacts of low-intensityjumps using a 4-square formationwould only allow room for 2 sets of 10repetitions of a high-intensity exercise,such as depth jumps. The proportionsof low-intensity, moderate, and highintensity work would depend on the objectives of the program and on the objectives of each session within aperiodized model. Once again, reiterating the importance of measurement andaccountability, a strength and conditioning coach who carefully monitorswork volume within athletes’ programswill be able to make more objective decisions with regard to progression, oreven with regard to tapering work whennecessary. In addition to work volume,the frequency of plyometric work andrecovery between sets are factors tomeasure and monitor as part of an objective-based strategic plan.Frequency and RecoveryAllowing 48–72 hours between low-intensity plyometric sessions will ensurethat adequate rest takes place and thatthe athlete is ready for the next plyometric workout. For example, a commonweekly schedule could include the submaximal jump patterns on lower bodystrength days, such as Tuesday and Fridays, with upper body sessions on Monday and Thursdays.Adequate recovery between sets in aworkout is equally important as adequate rest between workouts. A common work-to-rest ratio is 1:5. For example an exercise that takes 10 seconds toperform would have 50 seconds of restbetween sets. An important point toconsider with low-intensity plyometrics,particularly with the footwork patternspresented in this article, is that they aresubmaximal in nature. With this inmind, fatigue should not be a factorwith this type of work. As stated earlier,proprioception, postural control, anddynamic stabilization are points of emphasis with this mode of exercise. Again,fatigue should not be an issue if an athlete follows a course of progression, including development of an adequatestrength base (i.e., squats and step-ups),and practices landing strategies with adequate body control prior to performingactual working sets of low-intensityjump training. An athlete will not reacha fatigue state given submaximal intensity, short duration of activities, and appropriate work: rest ratios. Note thatsubmaximal footwork patterns/jumpsare often used as part of a warm-up inpreparation for moderate and high-intensity plyometrics (2). Otherwise, theycan be placed toward the end of a workout, following the primary work of theday (weight training, sprinting, andagilities).Safety ConsiderationsLow-intensity plyometrics should beperformed in areas that allow both adequate space and a yielding training surface. Multipurpose rooms (group fitnessclassrooms), gymnasium floors, andoutdoor fields are common places forperforming footwork patterns. As inmoderate and high-intensity plyomet-December 2005 Strength and Conditioning Journal

rics, submaximal jump patterns shouldnot be performed on cement or slipperysurfaces.Although it is common to use tape to setup the 4-square and staggered ladderpatterns, this article shows the use ofagility ladders for these exercises. Ladders are portable, easy to set up, andallow for consistency in the dimensionsof the patterns. Also, note that the ladders shown in this article are foam ladders, which adds to performance safetyshould an athlete not clear the lines andland on the ladder. Another safety pointto note is to use foam barriers, which arealso less likely to cause injury if landedon. Note that 2-inch, 4-inch, and 6-inchfoam blocks are the barriers used in the4-square and staggered ladder patternspresented in this article.Allowing time for an adequate warm upis another important safety consideration in preparing for low-intensity jumptraining. Jump rope is one simple way toprepare for the low-intensity jump patterns. For example:1. Jump rope for 2 minutes. Perform2–3 bouts with 60 seconds of dynamic stretching between bouts.2. Dynamic stretching can includemultidirectional lunging and standing quad/hip, hamstring, and lowerleg stretches.Readiness for Plyometrics:Medical and OrthopedicConsiderationsThere are important considerations thatneed to be entertained prior to beginninga plyometric program. In some circumstances, preexisting medical conditionsneed to be considered. These concernswould generally apply to elderly or pediatric populations. Certain conditions,such as diabetes or a current viral illness,can have a significant detrimental effecton even our most fit collegiate and professional athletes. It is important to ascertainthe athlete’s relevant past medical historyand especially the athlete’s current med-Figure 4. Both Munoz and 4-square formations using the plyo-ladder are illustrated.In this illustration, please note placement of the foam blocks.ical status, because it may be necessary insome cases to obtain formal medical clearance prior to starting the program.There are also important orthopedicconsiderations, as well as factors such asage, gender, physical maturity and experience level, which are crucial to the design of the specific program. What is appropriate for one 15 year old may not befor another. Structural and physiologicfactors may predispose adolescent females to exercise-related pain or injury.Any preexisting injury would have a veryimportant influence on the appropriateness of a specific program. For example,deep squats and resisted knee extensionmay be contraindicated in patients withsignificant patellofemoral symptoms. Agreater emphasis on hamstring andsoleus strengthening and cocontractionDecember 2005 Strength and Conditioning Journal15

strategies is appropriate in patients witha history of anterior cruciate ligament insufficiency. Likewise, athletes who haveundergone previous surgery may havespecific contraindications or require special areas of emphasis.Bodyweight and strength ratios are important factors to consider. For instance, it is suggested that an athlete tobe able to barbell squat 1.5 times his orher bodyweight (1 repetition maximum) before beginning high-intensityplyometrics such as depth jumps (2).This can be a dilemma for a high schoolathlete who could otherwise benefitfrom a plyometric program, but lacksthis type of strength. When an athlete isrunning, he or she is already imposingup to 3 times his or her bodyweight inforces through the knees. Therefore, asstated earlier, low-intensity plyometrics, such as submaximal footwork patterns, are a healthy alternative for youngathletes who lack an adequate strengthbase for performing high-intensity plyometrics (2). Continuing with the highschool athlete as an example, the submaximal footwork patterns will teach ayoung athlete to control his or her center of gravity, land softly, change direction quickly, and spend as little time onthe ground as possible. Low-intensityplyometrics can then be viewed as support work for healthier running inyoung athletes when combined withbodyweight resistance strength workand landing strategies.Low-intensity plyometrics are also a saferchoice for larger athletes, such as athletesweighing more than 220 pounds. For atall, 260-pound basketball player, the 4square drill can be viewed as a dynamicankle stabilization exercise and combinedin a lower-leg circuit, including wobbleboard exercises and resisted dorsiflexionwith a resistance band. In this case, submaximal footwork patterns that are plyometric in nature are a healthy alternativefor a heavier athlete, whereas high-intensity plyometrics may be contraindicatedbecause of bodyweight and sport de-16mands (e.g., basketball, a sport that innately includes high-volume/high-frequency jumping throughout a long season).And, of course, an adequate strengthbase is necessary prior to beginning anyplyometric program. Strength progressions should begin before plyometricprogressions. The athlete needs todemonstrate appropriate body controland exercise tolerance before progressing to the next level. The followingstrength movements are examples of thetype of progressive sequence that an athlete should be able to complete beforebeginning a plyometric program usingsubmaximal footwork patterns. Squatting and Step-UpsSquat is a body position and posture;squatting is a movement. The squat position is part of most functional activitiesand a prominent part of most sportsmovements. The functional progressionfor squatting is as follows: Squat position: An athlete shouldpractice the squat position as a prerequisite to performing the squatting movement. This is an exampleof static to dynamic progression.Controlling posture in a static squatposition involves (a) head/neckalignment (chin slightly in), (b)shoulder blades slightly back (slightscapulae retraction), and (c) maintaining lordosis in the low back inboth 2-leg and 1-leg squat positions.Squatting: The actual squatting action should begin as a slow movement and progress to a faster movement. This is a continuation offunctional progression, from (a) static to dynamic, then (b) slow to fastmovement(s). The manner in whichan athlete performs a squat will depend on the objectives of the exercise. Variations of a squatting actioncan include less or more ankle dorsiflexion with the tibia in a less ormore vertical position, and knee- orhip-dominant motion dependingwhat the movement is meant to accentuate. These actions will influence the body’s position (whether itwill be more upright or angled forward) naturally through a kineticlink system. Additional progressionsinclude changing the body’s base ofsupport to condition the hip musclesglobally, including the wide “sumo”squat, squat with a staggered legstance (asymmetrical), and 1-legsquat, as in Figure 2 (to name a few).Adding lateral and/or across thebody reaches while 1-leg squatting isa way to challenge frontal and transverse planes (1).Step-ups: Perform FW/BK and thenprogress to lateral step-ups. Step-upsare a healthy alternative to barbellresisted squats, particularly for prepubescent and adolescent athletesand for athletes for whom loadingthe spine directly is generally contraindicated. In a step-up, the heightof the bench is set according to theobjectives of the exercise and the degree of desired hip action involved.For example, if an athlete’s goal is toemphasize hip action and optimallyengage the gluteal muscles, he or shecan use a bench that allows the stepping leg to begin the step-up in a 90 hip-flexed position once the footsteps onto the bench. Like a squatting movement, varying degrees ofankle motion, lower leg positions,and knee/hip flexion relationshipswill be based on the objectives forperforming the exercise.Landing StrategiesLanding strategies are the next progression from squats and step-ups. Inessence, the landing position(s) of thebody in low-intensity plyometrics is apartial squat. A partial squat is a position with feet shoulder-width apart andthe bodyweight centered over a stablebase of support (BOS). Bearing weightsymmetrically, a stable BOS includes thetrunk being upright over the legs withslight flexion of the hips and knees, or apartial squat position. The partial-squatDecember 2005 Strength and Conditioning Journal

position may involve slightly more hipflexion (60–70 ) than knee flexion(30–45 ), keeping the knees posterior tothe toes. By maintaining a more perpendicular position of the tibia to theground, patellofemoral reaction forcesare minimized and anterior translationof the tibia is minimized as well, particularly because of the normally occurring7 posterior tilt of the tibial plateau (6).In short, the partial-squat position is animportant quality point in landingstrategies, which will, in turn, have acarryover effect to low-intensity jumptraining by:1. Minimizing risk of exercise-relatedknee injuries (minimizing patellofemoral reaction forces and anteriortibial translation), and2. Teaching an athlete to control thebody’s center of gravity within itsbase of support.Landing strategies bridge the gap between squats/step ups and the actuallow-intensity jump patterns by trainingan athlete to develop dynamic posturalcontrol in the partial-squat position andenhancing dynamic trunk stabilizationat ground contact when the feet hit theground. This type of training will have adirect transfer effect that carries over tojump training, particularly during theamortization phase(s) of each repetitionin a jump training set. The objective isto enhance proprioception and kinesthetic awareness during ground contacttime. It is also important to note thatwhen an athlete is able to control posture at ground contact, he or she will beable to change direction quickly andeasily, with minimal wasted movement(s).Examples of landing strategies could include the following jumps: FW and freeze.FW/BK and freeze.FW/BK/FW and freeze.Lateral right (R) and freeze.Lateral left (L) and freeze. R/L/R and freeze.L/R/L and freeze.Add 6-inch box to the above patterns.Practicing landing strategies is one example of controlled, proactive exercises.When an athlete demonstrates body control in the above exercises and has concurrently developed an adequate strengthbase, he or she will then progress to: Advanced controlled proactive typeexercises: Repetitions of preset jumppatterns (without freeze moments)that advance from FW/BK and L/Rmovement to adding diagonal patterns and foam barriers (see Instructions for Jump Patterns and Figure 4),andUncontrolled, reactive type of exercises (4). In this case, the athlete progresses to situations in which he orshe must control activity reactively.The above landing strategies andbelow jump patterns are examples ofcontrolled movement patterns simply because the athlete initiatesmovement. In uncontrolled reactiveexercises, the athlete reacts to a stimulus during eccentric, decelerationmoments. Using the 4-square jumppattern as an example, the athletewould progress from preset jumppatterns to random jump patternson command by the coach. In thiscase, the coach can combine both avisual and auditory stimulus to direct the athlete by calling out andpointing directions. Other examplesof controlled proactive versus uncontrolled reactive exercises wouldbe balancing on a wobble board ormini-trampoline, then progressingto catching and throwing while 2and 1-leg standing on the same apparatus, or progressing from lateralmovement on a slide board to catching and throwing with lateral movement on the slide board.Objectives for Jump PatternsObjectives for submaximal jump patterns include: Improve body control and movement in youth populations. Theseexercises are appropriate for youngathletes who may lack the strengthbase or physical maturity to undergothe rigors of a maximal effort plyometric workout.In-season maintenance conditioning. These exercises are appropriatefor collegiate and professional athletes in season who otherwise maylack adequate recovery time if performing maximal effort plyometrics.Improve dynamic stabilization strengthin feet/ankles. These exercises are prerequisites to agilities that requirestart and stops, cuts, pivots, andchange of direction.Footwork patterns with low-intensityplyometrics are common and found inspecial speed development programs.Chu (2) notes that some footwork patterns are based on the inverted funnelprinciple. The inverted funnel principleis based on the fact that athletic movements require an individual to oftenmove the feet out from under the body’scenter of gravity (COG) and then recover the position for a brief period of timeso as to regain balance and stability (2).The essence of footwork drills is thatthey teach an athlete to maintain theirbody’s COG in a relatively constant position while the feet rapidly work outfrom under it in multiple directions.The result is improved kinestheticawareness, or that sense of where thebody is in relation to the environment.Instructions for Jump PatternsThe following jump patterns are lowintensity plyometrics that follow a natural progression to the exercises notedin Landing Strategies. Figure 3 showsan athlete in position to begin a jumppattern in the 4-square formation. Thebody position in Figure 3 is an exampleof the partial-squat position describedearlier. Even though the athlete’s feetwill be traveling in and out of the boxesin prescribed patterns, the body’sCOG should remain constant. TheDecember 2005 Strength and Conditioning Journal17

to 6 and return from 6 to 1 for maxtime (2).Adding Foam Barriers: When jumpingfoam barriers, the method of countingchanges. Each foot contact is counted.Using the staggered ladders and box 1-2jumps with a foam barrier, count 1 whenthe athlete contacts box 2 on the initialjump, count 2 when the athlete touchesbox 1 on the return trip, and continue inthis manner for the remainder of thedrill time (10–20 seconds). Please noteFigure 5, which shows an athlete readyto begin performing jump patternsusing the staggered ladders.Figure 5.Athlete is in position to begin jump patterns in the Munoz formation.partial squat position depicted in Figure 3 will allow an athlete to controlthe body’s COG effectively duringsubmaximal footwork drills. Pleaserefer to Figure 4 for an illustration ofboth the staggered-ladder and 4-squarepatterns using 2 foam agility ladders,and the varied jump patterns in theseformations. Note how the boxes arenumbered (1–6 in the staggered-ladderand 1–4 in the 4-square). The generalrule for all patterns is to count “1” each18time the athlete returns to the startingpoint. For example, when performingthe staggered ladder pattern and goingfrom box 1 to box 2, the scorer willcount each time the athlete’s foot orfeet return to box 1. For a box 1-2-3pattern, again, count 1 each time theathlete’s foot or feet return(s) to box 1.In 1–6 for max-time (1, 2, 3, 4, 5, 6for

ditioning programs, including progres-sion in work volume and intensity. Functional Progression In Review Functional progression is a series of basic movement patterns graduated according to the difficulty of the skill and an ath-lete's tolerance (5). The primary objec-tive of functional progression in rehabili-