Transcript ess-110-demands-of-sport-powerpoint2

Demands of Sport
Track & Field: Warmup, Stretching, &
Flexibility
“Sprint and vertical jump performances are not affected by six
weeks of static hamstring stretching” (1)
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Observed effects of static
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stretching program on the
hamstring – evaluating:
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Hypothesis – flexibility program:
R/L knee joint ROM
Change in height of vertical jump
55m sprint times
participants in study:
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general knowledge and familiarity
with sprinting activity.
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Jumpers
Hurdlers
Sprinters
Throwers
Results:
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1.) decrease injury
2.) increases overall performance of
the athlete.
 increasing the muscles
pliability
 Decreasing energy necessary
to move the muscle.
Chronic static stretching:
 no effect on either sprinting or
jumping performance
 Provides only Slight increase
in ROM
Conclusion:
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Increases in chronic flexibility and
stretch tolerance do not result in
athletic performance improvements
Flexibility:
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The range of motion
through which the
body’s joints are able to
move.
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Determined by a
combination of the
elasticity or suppleness
or the muscles,
ligaments, and tendons.
“The impact of different warm-up protocols on vertical jump
performance in male collegiate athletes” (2)
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Most athletic program warm-ups have some variation on static
stretching structured into their routine
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Goal:
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is static stretching directly before power performance is detrimental to
power output
Effects
– 4 warm-up strategies were evaluated through:
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Assessing vertical jumps
Comparing the results with the pretest findings
Findings:
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stretching has been shown to inhibit performance; therefore, an
appropriate warm-up is critical to successful performance.
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support that the general warm-up plus dynamic flexibility can lead to better
performances.
Vertical Jump Test:
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Athlete stands with side to
wall
Keeping the feet flat on the
ground
Jumping vertically and
reaching with the hand
Touch the highest point
possible
Difference between reach
height & jump height is
score best of three recorded.
“Stretching: acute and chronic? The potential consequences”
(3)
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Goal:
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Effects:
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comparing differences between acute & chronic stretching programs on effects on
ROM, performance, force production, & injury prevention.
acute stretching decreases results of activity especially for events requiring use of
maximum & explosive strength related movements. This loss of explosive
capability may reduce one’s ability to perform.
acute stretching may affect ROM through:
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1.) altering the structure and properties of the soft tissue
2.) providing an increase in pain tolerance
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thus altering the muscles normal feedback to the nervous
system.
“A functional approach to warm-up and flexibility” (4)
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Goal: functional approach to preparing athletes for moving
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developing long-term soft tissue adaptations
improving ROM
enhance performance
enhance recovery
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well designed warm-up program will help the athlete prepare mentally for the upcoming competition
or practice
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Findings: two basic concepts for warm-up:
1.) raising internal temp
- allowing performance enhancing physiological chances to occur
2.) must be functional / integral part of training session & contribute to:
- development of balance/core strength/body control/running
mechanics/agility/efficient sport-specific movements.
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Flexibility: can be developed in the post workout and post competitive periods, as long
as the athletes’ program is well-planned and promotes long-term soft tissue
adaptations.
“Static stretching impairs sprint performance in collegiate
track and field athletes” (5)
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Goal:
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Subjects – tested as part of normal practice - 2 groups:
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increasing one’s flexibility will cause increases in performance
decreases in injury
Dynamic warm-up:
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Rest group
Stretching group
Previously Assumed:
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whether addition of pre-event stretching after dynamic warm-up
has negative effect on athlete’s performance.
effective way of enhancing athlete performance
Results: of this testing show no significant differences between either testing
session
Summary of Results
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results of study correlate with results from studies testing muscle
groups especially important to sprinting and jumping. (1)
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Correlating with past research - static stretching detrimental to power
output dynamic stretching has positive effects on performance. (2)
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findings from other studies supported, showing static stretching
associated with muscle damage. (3)
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decreased flexibility not responsible typical sports injuries. (3)
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static stretching prior to activity not supported by significant evidence
for a reduction in injuries. Engaging in static stretching prior to
explosive power activities may reduce capabilities for force production.
(4)
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. Recent studies established acute static stretching has adverse effects
on maximal performances, and inhibitory effects were seen in vertical
jump performance and running speed. (5)
References
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(1) - Bazett-Jones, DM, Gibson, MH, and McBride, JM. Sprint and vertical jump
performances are not affected by six weeks of static hamstring stretching. Journal
of Strength and Conditioning Research 22: 25 – 31, 2008.
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(2) - Holt, BW, and Lambourne, K. The impact of different warm-up protocols on
vertical jump performance in male collegiate athletes. Journal of Strength and
Conditioning Research 22: 226 – 229, 2008.
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(3) - Stone, M, O’Bryant, HS, Ayers, C, and Sands, WA. Stretching: acute and
chronic? The potential consequences. Strength and Conditioning Journal 28: 66 –
74, 2006.
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(4) - Swanson, JR. A functional approach to warm-up and flexibility. Strength and
Conditioning Journal 28: 30 – 36, 2006.
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(5) - Winchester, JB, Nelson, AG, Landin, D, and Young, MA. Static stretching
impairs sprint performance in collegiate track and field atheltes. Journal of
Strength and Conditioning Research 22: 13 – 18, 2008.