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15 THINGS YOU SHOULD KNOW BEFORE BEGINNING DEPTH JUMPS
by Dr. Mel Siff
1. Depth jumps require special preliminary preparation such as a significant volume of barbell exercises and traditional jumping, short sprints and skipping over a period of several months. One should begin at a relatively low height and increase it gradually to optimal height. It makes sense to begin jumping upward and forward only after sufficient training to jump strictly upward. Each exercise is executed in sets of 10 repetitions, with 1-5 minutes of rest between sets. Muscle or tendon fatigue, pain or soreness, as well as incompletely healed injuries are contra-indications to depth jumping.
2. The optimal dosage of depth jumps with an energetic vertical take-off in one training session should not exceed 4 sets of 10 jumps for well conditioned athletes and 2-3 sets of 5-8 jumps for lesser-conditioned athletes. Easy running and relaxation exercises for a period of 10-15 minutes should be done between sets.
3. Depth jumps executed in the volume indicated should be done once or twice a week in training sessions devoted to special strength training. Besides including depth jumps, these sessions include localized excesses for other muscle groups and general development exercises executed with a small volume. Well-conditioned athletes can execute depth jumps 3 times per week for 2 sets of 10 jumps at the completion of technical training in a particular sport.
4. Depth jumps strongly excite the nervous system. Therefore, they should be used not less than 3-4 days before a technique session. Sessions devoted to general physical preparation with a small volume of work should be done after depth jump workouts.
5. Depth jumps occupy a fundamental place in the second half of the preparatory period of a yearly cycle. However, they can function as a means of maintaining the achieved level of special strength fitness in the competition period. During the competition period they should be included once every 10-14 days, but no later than 10 days before a competition.
6. A useful initial sub-maximal plyometrics drill is hopping on the spot at a frequency which feels most comfortable for the athlete, using a few sets of about 25 repetitions. This enables the athlete to develop sensitivity to timing, optimal depth of the joint flexion and rebound coordination. These small vertical hops may then be replaced by small forward hops, backward hops, sideways hops, forward-backward hops and zigzag hops. Next, the athlete should try to execute the small vertical hops as rapidly as possible, again using a few sets of about 20 repetitions.
7. Skipping in different patterns, on one or both legs, with a rope can serve as a useful preparatory activity for depth jumps plyometrics. It should be remembered that the aim is not to improve endurance, but speed and speed-strength, so that the long periods of skipping rope are not the appropriate form of preparatory drill.
8. The optimal height of a depth jump does not result in a landing where the heel is forced to the ground by momentum.
9. Head posture and direction of gaze play important roles in controlling all aspects of depth jumping. Flexing the head downward to look at the floor before take-off may result in spurious muscle contraction or altered timing. Similarly, if the head is not thrust upwards during the take-off, maximal height will not be reached.
10. Depth jumping necessitates falling in a relaxed state, but not jumping off the box.
11. It is the quality of the plyometric exercises, not the quantity, which is important for the development of explosive strength and reactive ability.
12. Inappropriate breathing patterns reduce the effectiveness of the exercises. In particular, the breath should be held and never released during the contact phase or any other phases where maximal effort is to be produced. Exhalation during any landing phase reduces overall stability and increases the loading on the spine during depth jumps.
13. Before athletes attempt depth jumping, they must learn the techniques of normal jumping. It is important that they acquire competence in the use of the correct lumbar-pelvic rhythm, as is also used during clean pulls or power cleans from the ground. In this respect, these weightlifting maneuvers can be helpful in teaching efficient use of the knees, hips and spine.
14. Great caution must be exercised in performing any form of depth jump which involves one-legged thrusts, changes of direction or complex variations, since the risk of injury is significantly higher. The skills of such movements must be learned at progressively higher levels of complexity and intensity before maximal attempts are used.
15. The successful integration of depth jumps into a training program depends on not disrupting the delayed training effect prior to strength work. It should be noted that the use of depth jumps as a means of stimulation can delay this effect for 5-6 days.