The relationship between different types of strength and flexibility on vertical jumping

1. Richard Hobbs
110061502

2.  Jumping is used in a variety of sports and has many different
techniques (Grimshaw and Burden, 2007).
 1 rep max squat has a strong relationship with jump height
(Wisløff, Castagna, Helgerud, Jones & Hoff, 2006).
 Isometric contractions during countermovement (Umberger,
1998).
 The transfer of elastic energy influences countermovement jump
(Wilson, Wood & Elliot, 1992).

3.  The hypothesis for this study is that
 Both isometric and isokinetic strength will have a
significant correlation with jump height
 There will be a significant correlation between
flexibility and jump height.

4. • 20 participants
• 13 male, 7 female
• Age 21.2 ± 2.14 years
• Height 177.83 ± 8.15 cm
• Weight 71.8 ± 8.3 kg.

5. Strength
Biodex
dynamometer
Isometric
90° knee flexion
Away and toward
Isokinetic
120 deg/sec
180 deg/sec
Flexibility
Sit and reach test
ROM during
isokinetic test
Jumping
X5 standing
vertical jumps
X5 approach
vertical jumps
Matrax
Highest jump
used for analysis

6.  Pearson product moment correlation between isometric
measures, isokinetic measures and flexibility measures and
both types of jump height.
 Paired t-tests to determine any difference between relative
peak toque, average power and total work completed during
isokinetic tests, 120 deg/sec and 180 deg/sec.
 Alpha Level 0.05

7.  Significant positive correlations between all
variables and both types of jump except for
ROM, where no correlation was found between
either jump.

8. r=0.71
70.0
60.0
50.0
40.0
30.0
20.0
10.0
0.0
75 100 125 150 175 200 225
Standing Jump height (cm)
Relative peak torque (N/kg)
Knee extension 180 deg/sec

9. r=0.71
70.0
60.0
50.0
40.0
30.0
20.0
10.0
0.0
0 50 100 150 200 250
Approach jump height (cm)
Average Power (watts)
Knee flexion 180 deg/sec

10.  Muscular Strength findings supported by the findings of Van
Soest, Roebroeck, Bobbert, & Huijing (1985).
 Greater muscle strength enables performer to produce more
vertical force during countermovement phase, thus a greater force
acts upwards when pushing off, allowing larger propulsion and
greater jump height.
 The relationship between flexibility and jump height is
supported by Lian, Engebretsen, Øvrebø, & Bahr (1996).
 If a muscle has greater flexibility, more potential elastic energy can
be transferred during the countermovement phase of the jump to
kinetic energy producing greater height.

11.  Alignment of the lever during strength testing.
 Consistency of jumping technique.
 Marker movement during jumping.

12.  The difference in jump height between different
football/basketball/volleyball players.
 How the use of a target affects jump height.

13.  The aim of the study was to determine if there
was a relationship between isometric and
isokinetic strength and jump height. A second
aim was to the assess the relationship of
flexibility and jump height
 The hypothesises of the study were correct and
supported by the literature.
 More research could be developed on the
difference in jump height amongst different
sports.

14.  Grimshaw, P. and Burden, A. (2007). Sports and exercise Biomechanics. New York, NY:
Taylor and Francis Group.
 Umberger, B. R. (1998). Mechanics of the vertical jump and two-joint muscles:
Implications for training. Strength & Conditioning Journal, 20(5), 70-74. Retrieved from
http://www.umass.edu/locomotion/pdfs/scj-1998.pdf
 Wilson, G. J., Elliott, B. C., & Wood, G. A. (1992). Stretch shorten cycle performance
enhancement through flexibility training. Medicine and Science in Sports and
Exercise, 24(1), 116-123. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/1548985
 Wisløff, U., Castagna, C., Helgerud, J., Jones, R., & Hoff, J. (2004). Strong correlation of
maximal squat strength with sprint performance and vertical jump height in elite soccer
players. British journal of sports medicine, 38(3), 285-288. Retrieved from
http://bjsm.bmj.com/content/38/3/285.short

15. The Relationship between Different
Types of Strength, and Flexibility on
Vertical Jumping
Richard Hobbs
110061502