KINEMATIC PARAMETERS OF HURDLE CLEARANCE MOTION IN YOUNG, NOVICE ATHLETES

The purpose of the present study was to assess hurdle kinematics of young athletes when clearing the first two hurdles (0.76 m height) of a simulated hurdle race. Participants run the distance from the starting line to the 2nd hurdle. All trials were video recorded in order to evaluate specific kinematic variables related to hurdle clearance motion. Results revealed that young athletes negotiate the hurdles with lower values of horizontal velocity and hurdle clearance distance parameters, and tend to adopt “a jumping action” over the hurdle compared to the motor pattern of more skilled hurdlers. Horizontal velocity variation affected the technical model of hurdle clearance at the 2nd hurdle, compared to the 1st hurdle, forcing young participants to clear the 2nd hurdle with higher vertical displacement

STEP ADJUSTMENT IN LONG JUMP APPROACH IN BEGINNER ATHLETES AGED 12-13

This study examined whether young non-expert long jumpers showed at the long jump approach (LJA) similar pattern of variability in footfall placement across trials as adult expert athletes. The LJA of 51 competition jumps performed by 17 athletes, aged 12-13 years, were analyzed. A stride regulation pattern emerged on the 5th and 4th stride prior to take-off and at a mean distance of 8.7m (males) and 7.2m (females) from take-off board. TBD variability reached a maximum value of 32.1±19.9cm and 37.4±29.9cm and was finally reduced to 10.6±16.1cm and 15.6±14.4cm for males and females respectively. The striding pattern was similar to that reported in the literature for adults. However, beginners were found to be less consistent over the initial phase of the LJA than adult athletes and made more dramatic step length modifications during the final two strides

COMPARISON OF STEP CHARACTERISTIC INTERACTION AND ASYMMETRY BETWEEN FAILED AND SUCCESFUL ATTEMPTS IN POLE VAULT

The purpose of this study was to investigate step characteristics of high level pole vaulters during failed and successful jumps in terms of: a) the direction and magnitude of asymmetry between the pole carrying (PC) and non-pole carrying (NPC) foot and b) the reliance of step velocity (SV) on either step frequency (SF) or step length (SL). Eight male pole vaulters were recorded during competition with a panning video camera operating at 300 fps. Asymmetry was observed in four vaulters on either SF or SL both in successful and failed attempts but it was not consistent and its direction was not related to the athletes’ PC limb. No athletes demonstrated significant asymmetry for SV between failed and successful jumps. At the highest jump cleared, five out of eight vaulters demonstrated SF reliance. However, as the failed attempts progressed vaulters became less SF reliant

Biomechanical analysis of the late approach and the take off in the indoor women’s long jump

Aim of the study was to provide evidence concerning the biomechanical parameters of contemporary Women’s long jump in indoor competition. The final six steps and the take-off of 11 jumps (6.88 ± 0.23 m) were recorded (panning camera; sampling frequency: 300 fps) in an indoor competition. The examined parameters were a) the step parameters, the percentage distribution of adjustment (ADJ%) and the inter-limb symmetry angle (θSYM) in the late approach, b) the joint angles and the take-off parameters. Pearson’s correlation analysis revealed that approach velocity (9.8 ± 0.3 m/s) was significantly correlated (r = .86, p = .001) with effective distance (6.96 ± 0.23 m). The largest ADJ% (57.6 %) was executed at the penultimate step which was 12.2 ± 2.8 % larger than the last step. An inter-limb difference was revealed for step frequency (t10 = 6.965, p < .001) due to the large asymmetry observed (θSYM = 5.54 deg). The knee angle of the push-off leg at take-off was 171.2 ± 4.7deg. Resultant velocity (8.3 ± 0.4 m/s), height (1.15 ± 0.05 m) and angle (20.7 ± 2.3 deg) of take-off significantly predicted effective distance (F3,7 = 12.671, p = .003, R2 = .844). The present findings are in reasonable agreement with previous research. Future studies should examine the possible reliance and asymmetry for the step parameters in the final approach

Colour contrast and regulation of the long jump approach run

Research has shown that visual perception of the take-off board and the subsequent regulation of the approach run occur 4-5 strides prior to take-off. Contrast in visual perception is determined by the difference in colour and occurs when a surface of one colour induces its antagonist colour in an adjoining surface. The aim of the present study was to investigate if colour contrast between the track surface and the board affects the stride regulation pattern at the long jump approach run. Four long jumpers performed long jumps in two different occasions: 6 from a runway track coloured blue, with a white take-off board and 6 from a modified yellow board. The runway was marked and the approach runs were recorded with a panning camera. Toeboard distance (TBD) for each support phase in every run-up and the percentage distribution of adjustment of the regulated strides was calculated. With the white take-off board, the average TBD variability reached its peak value (21.74cm) on the 5th stride from the board and at a distance of 9.77m from take-off point. With the yellow take-off board the average TBD variability culminated (24.80cm) on the 7th stride from the board and at a distance of 13.40m from take-off point. With the white board, 80% of the adjustment was distributed during the last two strides as opposed to 61% with the yellow board. When a take-off board of a colour complementary to the runway’s blue track surface is used, athletes initiated their regulation 2 strides earlier. This may be attributed to an enhanced visual perception of the approaching target allowing a more uniform distribution of adjustments during the last two strides of the approach

STRIDE REGULATION AT THE APPROACH PHASE OF LONG JUMP IN VISUALLY IMPAIRED (F13) ATHLETES

The present work studied whether visually impaired (VI) class F13 long jumpers showed at the approach run the same pattern of variability in footfall placement across trials as their non-VI counterparts. The long jump finalists (men and women), of the IBSA 2009 European Athletics Championship were recorded. VI long jumpers demonstrated an initial ascending variability followed by a descending one suggesting some type of regulation. This control emerged on the 5th and 4th stride prior to take-off and at a mean distance of 8.8±1.9m and 8.3±2.6m from the take-off board for men and women respectively. TBD variability reached a maximum value of 30.0±18.9cm and 25.2± 14.4cm and was finally reduced to 7.73cm (± 6.65cm) and 8.2± 2.6cm for males and females respectively. The striding pattern observed was similar to that reported in the literature for non-VI athletes

THE USE OF UPPER LIMB PROSTHESIS OPTIMIZES LONG JUMP APPROACH KINEMATICS: A CASE STUDY OF AN ELITE T47 ATHLETE

This study aimed to investigate approach run kinematics using an upper limb prosthesis. A European Τ47 long- and triple- jump champion with right upper-limb congenital deficiency was analyzed in simulated approach run-ups wearing prosthesis (PW) or not (NP). Two attempts in each condition were recorded (300 fps). Step characteristics and kinematic parameters were extracted for the deficient (DLS) and intact (HLS) sides with a 2D-DLT analysis during the early (EA) and late (LA) approach. Results revealed systematic asymmetry for step frequency and length in NP, with the latter reduced in PW. Horizontal velocity in both EA and LA was larger by 0.3 m/s in PW than NP. These results suggest that asymmetry of NP reduces approach run performance compared to PW

STRIDE LENGTH REGULATION AT THE APPROACH PHASE OF LONG JUMP IN VISUALLY IMPAIRED (F12 CLASS) ATHLETES

The present study examined whether long jumpers with visual impairment (class F12) demonstrate at the approach run the same pattern of footfall variability across trials as athletes without visual impairment. Five male and five female elite F12 class long jumpers were recorded during a competition. The athletes demonstrated an initial ascending footfall variability followed by a descending one, suggesting the existence of stride length regulation. This regulation emerged on the fourth and the third stride prior to take-off area and at a mean distance of 9.09 ± 0.26 m and 6.28 ± 0.26 m for the males and the females respectively from the take-off line. Results indicated that the stride pattern of F12 class long jumpers was similar to that reported in the literature for athletes without visual impairment, with stride regulation commencing one stride closer to the take-off board

APPROACH SPEED, LAST STEP CHARACTERISTICS AND TAKE-OFF ACCURACY OF T36 CLASS PARALYMPIC LONG JUMPERS

The purpose of this study was to examine the approach speed (VAPP), the characteristics of the last three steps and the accuracy of foot placement at the take-off board (TTB) in T36 Paralympic long jumpers. Nine male finalists in the T36 Class long jump event who competed at the 2012 London Paralympics were analyzed using high speed video cameras and a speed radar gun. Results revealed that VAPP (8.0 ± 0.4 m/s) peaked at a distance of 6.40 ± 3.25 m from the take-off board. Both parameters were significantly correlated with the effective distance of the jump. TTB was 0.14 ± 0.10 m. There was no indication that the last steps were performed using the adequate step length for the proper execution of the “larger penultimate – shorter last step” technique. The adoption of this technique when approaching the take-off board may improve the effectiveness of the approach and aid in achieving a better take-off