Comparison of different drop jump heights on vertical

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INTRODUCTION: Studies have shown that when compared to other kinds of vertical jump, drop jumps (DJ) can increase maximal jump height. However, landing ...
Comparison of different drop jump heights on vertical jump performance in elite team handball players Douglas P. Marin1,2, Donizete C. X. de Oliveira2, Paulo B. Freitas Junior3, Luiz Moura Junior2, Gustavo P. Barbosa1, Ana M. F. Barela2, José Barela2. Metodista University 1, Cruzeiro do Sul University 2, University of Delaware 3 INTRODUCTION: Studies have shown that when compared to other kinds of vertical jump, drop jumps (DJ) can increase maximal jump height. However, landing from high levels can be detrimental to bone and joint structures and cause long-lasting injuries. The height from which the athlete should drop when practicing DJ is still matter of controversy. If dropping from a lower height is as effective as dropping from a high level in increasing jump height, it should be preferred in order to prevent injuries. PURPOSE: To examine the effects of different drop heights on the performance of drop jump in Brazilian elite team handball players. METHODS: Nine male team handball players (body mass 90.7±12.1kg; body height 184.3±8.9cm) were asked to drop from boxes 40, 60, and 80 cm high, and immediately perform a vertical jump as higher as possible. No arm swing was allowed. .A force plate (Kistler - Model 9286A) was used to measure the vertical component of ground reaction force (GRFV), recorded at 1 KHz by a customized LabView routine, which was also employed to calculate landing peak force (LPF1) and time to peak (TPF1) after the drop, contact time (CT), jump height (JH), and landing peak force (LPF2) and time to peak (TPF2) after the subsequent vertical jump. RESULTS: Except for LPF1 there were no effect of dropping height (40, 60, and 80 cm) on TPF1, CT, JH, LFP2, and TPF2. The landing peak force (LFP1) after the drop jump was significantly lesser when the participants dropped from 40 cm (DJ 40) when compared to dropping from other heights (DJ 60 and DJ 80), respectively by 42% and 48%.

DJ 40

DJ 60

DJ 80

LPF1 (N)

TPF1 (ms)

CT (ms)

JH (cm)

LPF2 (N)

TPF2 (ms)

Mean

2850.9 *

28.7

482.4

36.4

6831.5

49.1

SD

1343.1

13.3

87.1

8.3

2461.7

12.8

Mean

4877.7

25.9

483

36.2

6600.4

51.9

SD

1470.5

14.9

122.9

7.4

1308.1

19.8

Mean

5421.1

18.3

525.9

35.3

5751.8

47.3

SD

1823.6

12.6

93.9

7.8

1415.9

17.4

* p < 0.05 among DJ conditions.

CONCLUSION: The results indicate that, no matter from what height the participants dropped, the final outcome (jump height) is similar. However, dropping from a higher place generates more peak force, and consequently, more stress in bones and joints structures. In conclusion, dropping from 40 cm can be more effective (same performance outcome and lower bone and joints overloads) than from higher heights.