Journal of Strength and Conditioning Research Publish Ahead of Print DOI: 10.1519/JSC.0000000000000849
VERTICAL AND HORIZONTAL JUMP TESTS ARE STRONGLY ASSOCIATED WITH COMPETITIVE PERFORMANCE IN 100-M DASH EVENTS
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Submission type: Research Note
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Irineu Loturco1 ( ), Lucas Adriano Pereira¹, Cesar Cavinato Cal Abad¹, Ricardo Antônio D’Angelo2, Victor Fernandes2, Katia Kitamura1, Ronaldo Kobal1, Fabio Yuzo Nakamura3
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1- NAR - Nucleus of High Performance in Sport, São Paulo, SP, Brazil 2- BMF – BOVESPA, Track & Field Club, São Paulo, SP, Brazil
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3- State University of Londrina, Londrina, PR, Brazil
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Address for Correspondence:
Irineu Loturco ( ) NAR - Nucleus of High Performance in Sport.
Av. Padre José Maria, 555 - Santo Amaro, 04753-060 – São Paulo, SP, Brazil. Tel.: +55-11-3758-0918 E-mail:
[email protected]
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Running head: JUMP TESTS ARE RELATED TO SPRINTING PERFORMANCE
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ABSTRACT Fourteen male elite sprinters performed short-distance sprints and jump tests up to
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18 days prior to 100-m dash competitions in track & field to determine if these tests are
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associated with 100-m sprint times. Testing comprised squat jumps (SJ), countermovement
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jumps (CMJ), horizontal jumps (HJ), maximum mean propulsive power relative to body
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mass in loaded jump squats (MPPR) and a flying start 50-m sprint. Moderate associations
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were found between speed tests and competitive 100-m times (r = 0.54, r = 0.61 and r =
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0.66 for 10-, 30- and 50-m, respectively, P < 0.05). In addition, the MPPR was very largely
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correlated with 100-m sprinting performance (r = 0.75, P < 0.01). The correlations of SJ,
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CMJ and HJ with actual 100-m sprinting times amounted to -0.82, -0.85 and -0.81,
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respectively. Due to their practicality, safeness and relationship with the actual times
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obtained by top-level athletes in 100-m dash events, it is highly recommended that SJ,
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CMJ, and HJ be regularly incorporated into elite sprint testing routines.
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Keywords: sprinting; Olympic athletes; muscle power; speed performance; track & field;
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plyometrics
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INTRODUCTION Performance variance in endurance running competitions is largely explained by the
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triad maximal oxygen consumption, lactate threshold and running economy (19). For this
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reason, training intervention studies have aimed at improving these variables in isolation or
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in combination in order to enhance the athletes’ performance (31, 35). Surprisingly, to our
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knowledge, there are no studies investigating the associations between physical or
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physiological traits and competitive performance in sprinters, especially at the top-level.
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Therefore, finding competitive performance correlates in a relatively homogeneous group
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of sprinters is still a challenge. This is especially important at a time when upper human
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performance in the 100-m sprint is being discussed, due to the astonishing times obtained
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by both male and female athletes (16).
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The sprint exercise is predominantly supplied by the anaerobic turnover of
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adenosine triphosphate, with a significant drop in muscle pH and elevation in oxygen
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consumption (2, 5). Anaerobic capacity, as measured by maximal oxygen deficit, partly
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determines success in sprinting (29). However, this capacity has to be coupled with the
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ability to increase the rate of anaerobic energy release (36) (i.e., anaerobic power).
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Additionally, from a mechanical point of view, forces applied during the foot-ground
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contact are related to the ability to reach top speeds (37). The combined metabolic and
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mechanical factors related to sprinting cannot be fully manifested without the large prevalence of fast twitch fibers in the lower limb muscles (22) and training-related neural
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adaptations inherent to fast muscle activation (32). Similar characteristics appear to
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determine performance in other explosive tasks, such as vertical jumps (VJ) (14, 24).
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Therefore, positive associations are expected between jumping and sprinting abilities.
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The scarce literature using less qualified sprinters evidenced that VJ and drop-jump
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outcomes combined with the reactive strength index explained 89.6% of mean velocities in
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several sprinting distances (34). In top-level sprinters, loaded and unloaded jumping
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performances were highly correlated with the speed reached by elite sprinters in tests of up
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to 50-m (13, 23).From these results, it was suggested that strength-power development is
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important for athletes to achieve higher velocities over short-distances (23). It remains to be
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established whether actual performance in 100-m and personal bests are related to jumping
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ability. A recent editorial published in a sports science journal (11) claimed that regarding
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monitoring tools, cost- and time-effective systems resulting in simple practices should be
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sought rather than unnecessary complex systems. This is even more important in
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developing countries with low resources to assess athletes in sports disciplines like track &
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field sprinting.
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Therefore, the purpose of this study was to ascertain whether, for top-level sprinters,
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the actual performance in 100-m dash competitions is associated with neuromechanical
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capacities measured by specific short-distance speed assessments and jump tests (in loaded
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and unloaded conditions). Based on extensive published data confirming the strong
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correlations between various neuromuscular measures and sprinting ability (12, 18, 20, 23,
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26), we hypothesized that jump performance-related metrics would be significantly
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correlated with 100-m sprint times.
METHODS
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Experimental Approach to the Problem
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This study employed a cross-sectional correlational design to describe and explore
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the relationships between speed and vertical jump test results (in loaded and unloaded
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conditions), and actual 100-m dash performance in top-level sprinters. All sprinters were
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familiar with the testing procedures, which were carried out during the competitive training
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period, from 14 to 18 days prior to competitions where actual performance was measured.
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Before the tests – executed on the same day – the athletes performed 20-min of general and
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specific warm-up, including moderate running (10-min), active stretching (5-min) and
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specific sprint drills (5-min). The order of the evaluations was as follows: test 1) squat
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jumps (SJ) and countermovement jumps (CMJ); test 2) horizontal jumps (HJ); test3)
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sprinting speed; and (90-min afterwards) test 4) mean propulsive power in jump squats. The
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athletes received standard instructions on required pre-test behavior, including a minimum
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of 8-h sleep, balanced nutrition and avoidance of beverages or food containing alcohol and
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caffeine
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Subjects
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Fourteen male elite sprinters (age: 24.9 ± 3.8 years; height: 178.7 ± 6.4 cm and body
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mass: 77.8 ± 8.5 kg) volunteered to participate in the study. The sample comprised elite
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athletes who participated in Olympic, Pan-American and South-American Games, with
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personal records, on average, 7% longer than the men’s 100-m world-record (i.e., ≈ 10.28 ± 0.10 sec), thus attesting their high level of competitiveness. Athletes were briefed on the
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experimental risks and benefits of the study, and signed a written informed consent
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agreeing to take part. The study was approved by the local Ethics Committee.
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Vertical jumps
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VJs were assessed with the hands on the hips, using SJ and CMJ. For SJ, a static
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position with a 90° knee-flexion angle was maintained for 2-sec before each attempt
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without any preparatory movement. For CMJ, the sprinters performed a downward
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movement followed by a complete extension of the lower limbs, freely determining the
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amplitude of the countermovement. Five attempts at each jump were performed on a
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contact platform (Smart-Jump; Fusion Sport, Brisbane, Australia), interspersed by 15-sec
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intervals. The obtained flight time (t) was used to estimate the VJ height (h) (i.e., h = gt2/8).
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The best attempt was retained for further analysis.
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Horizontal jumps
Sprinters performed the HJ starting from a standing position. They commenced the
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jump by swinging their arms and bending their knees to provide maximal forward drive. A
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take-off line was drawn on the ground, positioned immediately adjacent to a jump sandbox.
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The jump-length measurement was determined using a metric tape measure (Lufkin,
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L716MAGCME, Appex Group, USA), from the take-off line to the nearest point of landing
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contact (i.e., back of the heels). Each athlete executed three attempts and the longest
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distance was considered.
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Jump squats
Mean propulsive power (MPP) was assessed in the jump squat exercise executed
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on a Smith-machine (Technogym Equipment, Cesena, Italy). Athletes performed three
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repetitions at maximal velocity for each load, starting at 40% body mass (BM); with loads
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of 10% BM progressively added in each set until a decrease in MPP was observed. Subjects
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executed a knee flexion until the thigh was parallel to the ground, then, following a
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command, jumped as quickly as possible without their shoulder losing contact with the bar.
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A 5-min interval was provided between sets. A linear transducer (T-Force, Ergotech,
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Murcia, Spain) attached to the Smith-machine bar was used to obtain the MPP. The bar-
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position data were sampled at 1,000 Hz using a PC (Toshiba, Tokyo, Japan). MPP rather
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than peak power was used as Sanchez-Medina et al. (33) observed that these mechanical
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values during the propulsive phase better reflect the differences in neuromuscular potential
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between individuals. This method avoids underestimation of the true strength potential as
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the higher the mean velocity (and lower the relative load), the greater the relative
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contribution of the braking phase to the entire concentric time. The relative values of MPP
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(MPPR) were obtained by dividing the higher values of MPP by the athletes’ BM (W/kg).
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Speed testing
Sprinters performed two attempts at a flying start 50-m test to assess maximum
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speed, with a 5-min interval between attempts. Four pairs of photocells (Smart-Speed,
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Fusion Equipment, Brisbane, Australia) were positioned at distances of 0-, 10-, 30- and 50-
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m. Athletes started each attempt 5-m behind the first photocell timing-gate, accelerating as
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much as possible before crossing the starting line. The best 50-m performance was retained.
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Statistical Analyses Data are presented as mean ± standard deviation (SD). A Pearson product moment
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correlation coefficient was used to analyze the relationships between jump and speed test
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results and actual sprinters’ performances during competition. The threshold used to
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qualitatively assess the correlations was based on Hopkins (17), using the following
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criteria: 0.9 nearly perfect. Data normality was checked via the Shapiro-Wilk test. The
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statistical significance level for all the analyses was set at P 0.05). The ICC for the jump squats, SJ,
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CMJ, HJ and sprint times in 10-, 30- and 50-m were all > 0.90. The CV for all variables
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analyzed was lower than 1%.
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Table 1 presents the means (SD) and the 95% confidence interval (CI) of the SJ,
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CMJ, HJ, MPPR, and the sprint times at 10-, 30-, and 50-m and competitive 100-m dash
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time. Table 2 shows the correlations between MPPR and short-distance sprint tests (10-,
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30-, and 50-m) with actual 100-mperformance. Large associations were found between
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speed tests and competitive 100-m times (r = 0.54, r = 0.61 and r = 0.66 for 10-, 30- and
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50-m, respectively, P < 0.05). The MPPR was very largely correlated with 100-m sprinting
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performance (r = 0.75, P < 0.01). Figure 1 depicts the correlations between SJ, CMJ, and
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HJ and 100-m dash times. The jump tests were very largely associated with 100-m dash
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performance (r = -0.82, r = -0.85 and r = -0.81 for SJ, CMJ, and HJ, respectively, P < 0.01).
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***INSERT TABLE 1 HERE***
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***INSERT TABLE 2 HERE***
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***INSERT FIGURE 1 HERE***
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DISCUSSION This study aimed to identify potential factors associated with sprinters’ performance
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in official competitions. The main finding of this investigation was that, providing they are
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executed few days (~2 weeks) before the competition, simple vertical and horizontal jump
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test outcomes are very largely associated with actual 100-m dash performance in a sample
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composed of male top-level sprinters. Moreover, the relative outputs of mean propulsive
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power collected during jump squats demonstrated a correlation of -0.75 with actual speed
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achieved by these athletes. Importantly, despite their apparent specificity, the “partial-
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distance velocity tests” have only a moderate correlation with 100-m dash times.
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The fact that practical jump tests are related to competitive sprinting performance is
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very remarkable. Sprint training methods are full of technology, and the possibility of
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monitoring sprinters’ athleticism using non-expensive tests especially favors the track &
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field programs developed across emergent countries. Similarly, even the leading sports
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nations may benefit from this method, as head coaches and strength & conditioning
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specialists avoid assessing athletes’ speed close to competitions due to the high risk of
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injury involved in all-out tests. Despite the simplicity of the assessments, unloaded jump tests (SJ, CMJ and HJ)
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had stronger associations with sprinting performance than MPPR. It must be mentioned that
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the MPPR is measured “on the barbell” and it does not reflect the actual power output of a
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given movement (8, 9, 27).Conversely, jump heights are measures able to express values
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already corrected by the body weight. If during a VJ a subject jumps higher, he necessarily
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produces higher values of relative force and relative power (N.kg-¹ and W.kg-¹,
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respectively) than his weaker counterpart (3, 7). To achieve maximal height during a jump
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attempt, the athlete’s center of mass needs to be as high as possible (in relation to the
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ground), attaining the highest vertical velocity at the take-off (15). At this moment, the
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subject follows a sequential pattern of lower limb segmental rotation, resulting in a great
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amount of external forces, which are applied to overcome the inertia and accelerate the
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body vertically (6). As the ground reaction force increases, the jump height increases.
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Equally, the transition from lower to higher velocities (i.e., top-speed sprinting) results in
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shorter support phase duration with a concomitant increase in vertical peak force (28). In
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addition, the distances achieved during HJ are dependent on the athletes’ ability to transfer
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the linear momentum of force directly from the ground to the peak horizontal acceleration
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of the body’s centre of mass, which is also critical to break the inertia and attain high
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velocities over short-distances (4, 18, 23). It is reasonable to assume that these mechanical
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relative values tend to be more associated with the sprinters’ actual performance, since
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during the competitions they have to push their bodies forward as rapidly as possible,
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applying great amounts of force against the ground.
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The strong relationship between MPPR and 100-m sprint-times (r = -0.75) cannot
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be overlooked. However, loaded jump testing may be potentially dangerous for athletes
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when performed a short time before competitions (30). Differently from unloaded conditions (SJ and CMJ), jump squats using loads close to or higher than BM may
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represent risks to joints and spine, by substantially increasing the ground reaction forces at
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the landing moment (38). To some extent, the stronger values of correlation coefficients
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(with 100-m times) presented by CMJ and SJ (r ≈ -0.84) when compared to loaded
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conditions (r = -0.75, for MPPR) may be explained by the mechanical principles involved
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in these assessments. The jump height is entirely related to the body’s vertical acceleration
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and the acceleration is equal to force divided by mass (i.e., sprinter’s weight) (21). As a
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result, for unloaded circumstances, higher jumping heights do not indicate only higher
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values of relative force, but furthermore, indicate superior capacities to accelerate one’s
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own body weight (1). Conversely, during jump squats, the power outputs (MPPR) are
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directly collected from the barbell, which do not reflect the actual mechanical values (i.e.,
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acceleration and velocity) of the athletes’ body centre of mass during a given movement
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(10). It is conceivable that these mechanical differences may influence our findings,
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resulting in stronger associations between sprinting times and unloaded vertical jumps.
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Finally, the “loaded jump squat” evaluations are long lasting and involve expensive
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equipment (i.e., linear position transducers), limiting their usefulness in the field, while
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unloaded jump heights can be measured by simple “vertical jump-and-reach tests” (8).
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Nevertheless, both unloaded and loaded jump squats are fed by the immediate energy
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supply from the intramuscular phosphagens and require the neural control inherent to
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ballistic movements that are also important in sprinting (32, 36).
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In addition to the aforementioned weaker correlations with actual sprint times, all-
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out speed assessments also involve inherent risks (e.g., muscle and tendon injuries). It is
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likely that closer proximity to competitions contributes to raising the fear presented by
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coaches and athletes when executing speed tests, thus compromising their outcomes and reducing the correlations between “sprint-test-times” and “sprint-competition-times”. This
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is due to the fact that top running speeds are related to high ground reaction forces rather
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than more rapid repositioning of limbs in the air, meaning that the will to maximally engage
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neuromuscular abilities is a prerequisite for achieving best performances in all-out speed
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tests (37). Increases in the magnitude of the eccentric forces – and, consequently, in the
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ground reaction forces -at the landing moment during the “loading stance phase” may result
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in undesirable injury risks (25). This study is limited by the relatively small sample size. On the other hand, to our
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knowledge this is the first study testing the relationship between unloaded and loaded jump
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test performances and actual competitive performance in high caliber athletes. Hence,
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interpretation of the results should take this important aspect into account.
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To conclude, as long as they are executed few weeks before the competitions,
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vertical and horizontal jump tests are directly related with 100-m dash times. The results
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presented herein confirm that coaches are able to determine the readiness of their athletes
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for 100-m performance by using simple SJ, CMJ and HJ. Short-distance speed test results
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and jump squat power outputs (MPPR) have weaker correlations than unloaded jump
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heights and distance (SJ, CMJ and HJ) with actual sprinting performance. Additionally,
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these measurements involve a number of intrinsic problems, such as injury risks,
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assessment time required and expensive equipment costs. Finally, with the stronger
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correlations presented by practical unloaded jumps, these assessments should be considered
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reliable enough to be related to actual sprinting times in highly competitive sprinters.
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PRACTICAL APPLICATIONS
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From a practical perspective, simple jump tests can be used to assess the readiness
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Anecdotally, assessing performance using these tests is a common practice in track & field;
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however, it is possible that coaches are not aware of the strong and real potential of the
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outcomes to forecast forthcoming competitive sprinting results. Therefore, we suggest that
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measuring lower limb explosiveness by means of unloaded vertical jumps (SJ and CMJ)
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and HJ may be useful in training and testing routines, due to their safeness and ability to
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strongly explain 100-m dash performance in top-level athletes. Further longitudinal studies
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are needed to fully elucidate the validity of jump tests in predicting changes in sprinters’
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performance (i.e., longitudinal validity) due to training and the potential effects of tapering
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and detraining periods on this relationship.
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Weyand PG, Lee CS, Martinez-Ruiz R, Bundle MW, Bellizzi MJ, and Wright S. High-speed running performance is largely unaffected by hypoxic reductions in
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aerobic power. J Appl Physiol 86: 2059-2064, 1999.
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Weyand PG, Sternlight DB, Bellizzi MJ, and Wright S. Faster top running speeds are achieved with greater ground forces not more rapid leg movements. J Appl
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Physiol 89: 1991-1999, 2000.
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38.
EP
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Zink AJ, Perry AC, Robertson BL, Roach KE, and Signorile JF. Peak power, ground reaction forces, and velocity during the squat exercise performed at different
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loads. J Strength Cond Res 20: 658-664, 2006.
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C C
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FIGURE LEGEND
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Figure 1. Correlations between vertical (unloaded conditions) and horizontal jump tests
379
with actual 100-m dash times (**P< 0.01).
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D
381 382
TE
383 384 385
EP
386 387 388
391 392 393
A
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C C
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Copyright Ó Lippincott Williams & Wilkins. All rights reserved.
Table 1. Descriptive analysis (mean, standard deviation [SD], and 95% confidence interval, [CI]) of the jumps in loaded and unloaded conditions, and short-distance sprint tests. CI (95%)
Mean ± SD
Lower
Upper
47.99 ± 3.68
45.86
50.11
CMJ (cm)
50.79 ± 4.16
48.38
53.19
HJ (m)
2.90 ± 0.11
2.84
2.96
10-m (s)
1.27 ± 0.02
1.26
30-m (s)
3.31 ± 0.04
3.29
D
SJ (cm)
1.28
TE
3.33
50-m (s)
5.20 ± 0.07
5.16
5.24
MPPR (W.kg )
13.46 ± 0.61
13.11
13.81
TIME (s)
10.49 ± 0.19
10.38
10.60
-1
EP
SJ = squat jump; CMJ = counter movement jump; MPPR = mean propulsive power
A
C C
relative to body mass; TIME = 100-m sprint time.
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Table 2. Correlations between short-distance sprints (at 10-, 30- and 50-m), mean propulsive power relative to body mass (MPPR) and actual 100-m dash times (TIME). 10-m
50-m
MPPR
TIME
**
#
0.51
-0.54
*
0.54*
1
0.77
30-m
0.77**
1
0.84**
-0.62*
0.61*
50-m
0.51#
0.84**
1
-0.67**
0.66**
MPPR
-0.54*
-0.63*
-0.67**
1
-0.75**
TIME
0.54*
0.61*
0.66**
-0.75**
1
P = 0.06, *P < 0.05, **P< 0.01.
D
10-m
A
C C
EP
TE
#
30-m
Copyright Ó Lippincott Williams & Wilkins. All rights reserved.
D TE EP C C A Copyright Ó Lippincott Williams & Wilkins. All rights reserved.