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AbstractThe aim of the study was to examine differences in an area of take-off strength between the elite and sub-elite sprinters. Drop jump–45cm tests were used as criteria of take-off strength. Sample of measured subjects included 12 best sprinters. They divided in two sub-groups with the official 100-metre sprint running result being used as a grouping criterion. Biomechanical parameters of both jumpswere measured with the use of bipedal tensiometric platform and a system of 9 infraspectral CCD cameras with a 200 Hz frequency.Differences between the groups of sprinters were examined with the use of ANOVA variance analysis. Statistically significant (p< 0.05)differences between the sprinters of both groups were revealed in three kinematic and kinetic parameters. In drop jump, elite and sub-elite sprinters differentiated in the realisation of movement velocity in the eccentric and concentric phases (a difference between thegroups is statistically significant p< 0.05). Elite sprinters better utilise the stretch reflex, which allows them to more efficiently transferelastic energy from first into second phase of take-off action

Background

In recent years, there has been a proliferation of technology and sport science utilized within an athlete's training, especially at the elite level. However, the sport science is a broad field, encompassing disciplines such as biomechanics, motor control and learning, exercise physiology, sports medicine, sport psychology to name a few. Rarely are these disciplines applied in an integrated manner. The purpose of this study was to document the effectiveness of an integrated biomechanics and motor control protocol for improving athlete's performance in the high jump.

Methods

Four elite high jumpers performed baseline jumps under normal conditions and then jumps using a specific external focus of attention cue designed to improve their running posture. Three-dimensional biomechanical analysis was used to quantify the upright posture throughout the approach as well as horizontal velocity at plant and vertical velocity at takeoff.

Results

The results showed that when using the external focus of attention cue, the jumpers were significantly more upright during the approach, had significantly higher horizontal velocities at plant, and generated significantly greater vertical velocities during the takeoff.

Conclusion

The results of this study lay the foundation for future work examining how integrating sport science disciplines can improve performance of elite level athletes.

When a performer adopts an internal focus of attention, he or she is thinking about the movements of their body. In contrast, an external focus of attention is utilized when a performer thinks about the effects of their movements on the environment. The focus of attention literature overwhelmingly suggests that compared to an internal focus of attentions, when performers adopt an external focus of attention, they demonstrate better outcome and performance production measures.5, 6, 7, 8 and 9 The literature also suggests that high level performers benefit more from using an external focus of attention than novice performers.10, 11 and 12 Therefore, using appropriate focus of attention cues is critical for optimizing elite level sport performance.

For the intervention a small piece of athletic tape was placed on the athlete's shirt, approximately at the level of the navel. In an effort to ensure that the athlete adopted an upright posture prior to entering the curve, while also focusing their attention externally, the participants were instructed to “lead with the tape” as they transitioned from the 4th to 5th steps of the approach. Participants completed two practice runs while being verbally cued between the 4th and 5th steps, and then completed a second jump for analysis.

The duration of time spent on the penultimate step was not different between pre- and post-intervention; however, the percentage of horizontal velocity lost during the penultimate step was reduced after the intervention. Moreover, the horizontal velocity brought onto the plant step was higher after the intervention and the vertical velocity at the end of the takeoff was also higher after the intervention

The results of the current study are in agreement with a growing body of attentional focus literature which suggests that using an external focus of attention improves outcomes and performance production measures. An external focus of attention has been documented to improve performance in activities involving whole body movements such as standing long jump,9 vertical jump and reach,19 baseball batting,12 golf swing,10 and 11 swimming,20 and in activities involving small movements and fine motor control such as dart throwing8 and playing of musical instruments.21 The benefits of an external focus of attention compared to an internal focus of attention can be explained using the constrained action hypothesis. According to the constrained action hypothesis, an internal focus of attention causes performers to intervene in control processes that regulate the coordination of movements, inadvertently overriding processes that allow for efficient movement. In essence, an external focus of attention allows more efficient movement.

The theory of myofascial pain syndrome (MPS) caused by trigger points (TrPs) seeks to explain the phenomena of muscle pain and tenderness in the absence of evidence for local nociception. Although it lacks external validity, many practitioners have uncritically accepted the diagnosis of MPS and its system of treatment. Furthermore, rheumatologists have implicated TrPs in the pathogenesis of chronic widespread pain (FM syndrome). We have critically examined the evidence for the existence of myofascial TrPs as putative pathological entities and for the vicious cycles that are said to maintain them. We find that both are inventions that have no scientific basis, whether from experimental approaches that interrogate the suspect tissue or empirical approaches that assess the outcome of treatments predicated on presumed pathology. Therefore, the theory of MPS caused by TrPs has been refuted. This is not to deny the existence of the clinical phenomena themselves, for which scientifically sound and logically plausible explanations based on known neurophysiological phenomena can be advanced.

Discussion
Whereas the increased PPT following ipsilateral massage (Ipsi-R and Ipsi-M) might be attributed to the release of fibrous adhesions; the non-localized effect of rolling massage on the contralateral limb suggests that other mechanisms such as a central pain-modulatory system play a role in mediation of perceived pain following brief tissue massage.

Conclusion
Overall, rolling massage over a tender spot reduces pain perception.

The Effects of Myofascial Release With Foam Rolling on Performance
Healey, Kellie C.1; Hatfield, Disa L.1; Blanpied, Peter2; Dorfman, Leah R.1; Riebe, Deborah1

Collapse BoxAbstract
Abstract: Healey, KC, Hatfield, DL, Blanpied, P, Dorfman, LR, and Riebe, D. The effects of myofascial release with foam rolling on performance. J Strength Cond Res 28(1): 61–68, 2014—In the last decade, self-myofascial release has become an increasingly common modality to supplement traditional methods of massage, so a masseuse is not necessary. However, there are limited clinical data demonstrating the efficacy or mechanism of this treatment on athletic performance. The purpose of this study was to determine whether the use of myofascial rollers before athletic tests can enhance performance. Twenty-six (13 men and 13 women) healthy college-aged individuals (21.56 ± 2.04 years, 23.97 ± 3.98 body mass index, 20.57 ± 12.21 percent body fat) were recruited. The study design was a randomized crossover design in which subject performed a series of planking exercises or foam rolling exercises and then performed a series of athletic performance tests (vertical jump height and power, isometric force, and agility). Fatigue, soreness, and exertion were also measured. A 2 × 2 (trial × gender) analysis of variance with repeated measures and appropriate post hoc was used to analyze the data. There were no significant differences between foam rolling and planking for all 4 of the athletic tests. However, there was a significant difference between genders on all the athletic tests (p ≤ 0.001). As expected, there were significant increases from pre to post exercise during both trials for fatigue, soreness, and exertion (p ≤ 0.01). Postexercise fatigue after foam rolling was significantly less than after the subjects performed planking (p ≤ 0.05). The reduced feeling of fatigue may allow participants to extend acute workout time and volume, which can lead to chronic performance enhancements. However, foam rolling had no effect on performance.