ACUTE EFFECTS OF A WARM-UP INCLUDING ACTIVE, PASSIVE, AND DYNAMIC STRETCHING ON VERTICAL JUMP PERFORMANCE

Carvalho, FLP, Carvalho, MCGA, Simao, R, Gomes, TM, Costa, PB, Neto, LB, Carvalho, RLP, and Dantas, EHM. Acute effects of a warm-up including active, passive, and dynamic stretching on vertical jump performance. J Strength Cond Res 26(9): 2447-2452, 2012-The purpose of this study was to examine the acute effects of 3 different stretching methods combined with a warm-up protocol on vertical jump performance. Sixteen young tennis players (14.5 +/- 2.8 years; 175 +/- 5.6 cm; 64.0 +/- 11.1 kg) were randomly assigned to 4 different experimental conditions on 4 successive days. Each session consisted of a general and specific warm-up, with 5 minutes of running followed by 10 jumps, accompanied by one of the subsequent conditions: (a) Control Condition (CC)-5 minutes of passive rest; (b) Passive Stretching Condition (PSC)-5 minutes of passive static stretching; (c) Active Stretching Condition (ASC)-5 minutes of active static stretching; and (d) Dynamic Stretching Condition (DC)-5 minutes of dynamic stretching. After each intervention, the subjects performed 3 squat jumps (SJs) and 3 countermovement jumps (CMJs), which were measured electronically. For the SJ, 1-way repeated measures analysis of variance (CC x PSC x ASC x DC) revealed significant decreases for ASC (28.7 +/- 4.7 cm; p = 0.01) and PSC (28.7 +/- 4.3 cm; p = 0.02) conditions when compared with CC (29.9 +/- 5.0 cm). For CMJs, there were no significant decreases (p > 0.05) when all stretching conditions were compared with the CC. Significant increases in SJ performance were observed when comparing the DC (29.6 +/- 4.9 cm; p = 0.02) with PSC (28.7 +/- 4.3 cm). Significant increases in CMJ performance were observed when comparing the conditions ASC (34.0 +/- 6.0 cm; p = 0.04) and DC (33.7 +/- 5.5 cm; p = 0.03) with PSC (32.6 +/- 5.5 cm). A dynamic stretching intervention appears to be more suitable for use as part of a warm-up in young athletes.

Pre Vertical Jump Performance to Regulate the Training Volume

The purpose of this study was to assess the effect of training load regulation, using the CMJ at the beginning of the session, on the total plyometric training load and the vertical jump performance. 44 males were divided into 4 groups: No Regulation Group (nRG), Regulation Group (RG), Yoked Group (YG) and Control Group (CG). The nRG received 6 weeks of plyometric training, with no adjustment in training load. The RG underwent the same training; however, the training load was adjusted according to the CMJ performance at the beginning of each session. The adjustment made in RG was replicated for the volunteers from the corresponding quartile in the YG, with no consideration given to the YG participant's condition at the beginning of its session. At the end of the training, the CMJ and SJ performance of all of the participants was reassessed. The total training load was significantly lower (p=0.036; ES=0.82) in the RG and the YG (1905 +/- 37 jumps) compared to the nRG (1926 +/- 0 jumps). The enhancement in vertical jump performance was significant for the groups that underwent the training (p<0.001). Vertical jump performance, performed at the beginning of the session, as a tool to regulate the training load resulted in a decrease of the total training load, without decreasing the long-term effects on vertical jump performance.

Ten minutes of dynamic stretching is sufficient to potentiate vertical jump performance characteristics

The current literature recommends dynamic rather than static stretching for the athletic warm-up. Dynamic stretching and various conditioning stimuli are used to induce potentiation in subsequent athletic performance. However, it is unknown as to which type of activity in conjunction with dynamic stretching within a warm-up provides the optimal potentiation of vertical jump performance. It was the objective of the study to examine the possible potentiating effect of various types of conditioning stimuli with dynamic stretching. Twenty athletes participated in 6 protocols. All the experimental protocols included 10 minutes of dynamic stretching. After the dynamic stretching, the subjects performed a (a) concentric (DS/CON): 3 sets of 3 repetition maximum deadlift exercise; (b) isometric (DS/ISOM): 3 sets of 3-second maximum voluntary contraction back squats; (c) plyometric (DS/PLYO): 3 sets of 3 tuck jumps; (d) eccentric (DS/ECC): 3 modified drop jumps; (e) dynamic stretching only (DS), and (f) control protocol (CON). Before the intervention and at recovery periods of 15 seconds, 4, 8, 12, 16, and 20 minutes, the participants performed 1-2 maximal countermovement jumps. The DS and DS/CON protocols generally had a 95-99% likelihood of exceeding the smallest worthwhile change for vertical jump height, peak power, velocity and force. However, the addition of the deadlift to the DS did not augment the potentiating effect. Time-to-peak potentiation was variable between individuals but was most consistent between 3 and 5 minutes. Thus, the volume and the intensity associated with 10 minutes of dynamic stretching were sufficient to provide the potentiation of vertical jump characteristics. Additional conditioning activities may promote fatigue processes, which do not permit further potentiation.

The rating of perceived exertion predicts intermittent vertical jump demand and performance

The aims of this study were (a) to assess the ability of the rating of perceived exertion (RPE) to predict performance (i.e. number of vertical jumps performed to a fixed jump height) of an intermittent vertical jump exercise, and (b) to determine the ability of RPE to describe the physiological demand of such exercise. Eight healthy men performed intermittent vertical jumps with rest periods of 4, 5, and 6s until fatigue. Heart rate and RPE were recorded every five jumps throughout the sessions. The number of vertical jumps performed was also recorded. Random coefficient growth curve analysis identified relationships between the number of vertical jumps and both RPE and heart rate for which there were similar slopes. In addition, there were no differences between individual slopes and the mean slope for either RPE or heart rate. Moreover, RPE and number of jumps were highly correlated throughout all sessions (r=0.97-0.99; P0.001), as were RPE and heart rate (r=0.93-0.97; P0.001). The findings suggest that RPE can both predict the performance of intermittent vertical jump exercise and describe the physiological demands of such exercise.

Dynamic exercise versus tag game warm up: The acute effect on agility and vertical jump in children

Although dynamic and stretching exercises have been widely investigated, there is little information about warm up performed by tag games. Thus, the purpose of the present study was to verify the acute effect of dynamic exercises compared to a tag game warm up on agility and vertical jump in children. 25 boys and 24 girls participated in this study and performed the agility and vertical jump tests after warm up based on dynamic exercises or as a tag game lasting 10 min each in two different days randomly. Dynamic exercises warm up consisted in a run lasting 2.5 min followed by 2 series of 8 dynamic exercises lasting 10 seconds each interspersed with 20s of light run to recovery. Tag game warm up was performed by a tag game with two variations lasting 5 min each. The first variation there was a single cather, which aimed to get the other participants by touching hands. In the second part of the game, the rules were the same except that the participant that was caught had to help the catcher forming a team of catchers. Warm up intensity was monitored by OMNI perceived exertion scale. ANOVA 2x2 for repeated measures (Warm up x Sex) demonstrated no significant differences between dynamic exercises and tag game for agility and vertical jump (P>0.05) for boys and girls. Perceived exertion was significantly higher in tag game compared to dynamic exercises on girls (P<0.05). Both warm up models showed similar acute effects on agility and vertical jump in children. © Faculty of Education. University of Alicante.

Influence of a preventive training program on lower limb kinematics and vertical jump height of male volleyball athletes

Objective: To examine the influence of a preventative training program (PTP) on sagittal plane kinematics during different landing tasks and vertical jump height (VJH) in males. Design: Six weeks prospective exercise intervention. Participants: Fifteen male volleyball athletes (13 ± 0.7 years, 1.70 ± 0.12 m, 60 ± 12 kg). Interventions: PTP consisting of plyometric, balance and core stability exercises three times per week for six weeks. Bilateral vertical jumps with double leg (DL) and single leg (SL) landings were performed to measure the effects of training. Main outcome measurements: Kinematics of the knee and hip before and after training and VJH attained during both tasks after training. The hypothesis was that the PTP would produce improvements in VJH, but would not generate great changes in biomechanical behavior. Results: The only change identified for the SL was the longest duration of landing, which represents the time spent from initial ground contact to maximum knee flexion, after training, while increased angular displacement of the knee was observed during DL. The training did not significantly alter the VJH in either the SL (difference: 2.7 cm) or the DL conditions (difference: 3.5 cm). Conclusions: Despite the PTP's effectiveness in inducing some changes in kinematics, the changes were specific for each task, which highlights the importance of the specificity and individuality in selecting prevention injury exercises. Despite the absence of significant increases in the VJH, the absolute differences after training showed increases corroborating with the findings of statistically powerful studies that compared the results with control groups. The results suggest that short-term PTPs in low risk young male volleyball athletes may enhance performance and induce changes in some kinematic parameters. © 2012 Elsevier Ltd.

An investigation of lower limb joint powers as a predictive measure of countermovement vertical jump height.

Measuring and tracking athletic performance is crucial to an athlete’s development and the countermovement vertical jump is often used to measure athletic performance, particularly lower limb power. The linear power developed in the lower limb is estimated through jump height. However, the relationship between angular power, produced by the joints of the lower limb, and jump height is not well understood. This study examined the contributions of the kinetic value of angular power, and its kinematic component, angular velocity, of the lower limb joints to jump height in the countermovement vertical jump. Kinematic and kinetic data were gathered from twenty varsity-level basketball and volleyball athletes as they performed six maximal effort jumps in four arm swing conditions: no-arm involvement, single-non-dominant arm swing, single-dominant arm swing, and two-arm swing. The displacement of the whole body centre of mass, peak joint powers, peak angular velocity, and locations of the peaks as a percentage of the jump’s takeoff period, were computed. Linear regressions assessed the relationship of the variables to jump height. Results demonstrated that knee peak power (p = 0.001, ß = 0.363, r = 0.363), its location within takeoff period (p = 0.023, ß = -0.256, r = 0.256), and peak knee peak angular velocity (p = 0.005, ß = 0.310, r = 0.310) were moderately linked to increased jump height. Additionally, the location, within the takeoff period, of the peak angular velocities of the hip (p = 0.003, ß = -0.318, r = 0.419) and ankle (p = 0.011, ß = 0.270, r = 0.419) were positively linked to jump height. These results highlight the importance of training the velocity and timing of joint motion beyond traditional power training protocols as well as the importance of further investigation into appropriate testing protocol that is sensitive to the contributions by individual joints in maximal effort jumping.

Analyses and comparison of counter-movement jump performance and self-rated recovery in state under-18s Australian Rules Football players during a national championship

Recovery of team sport athletes during multiple competitive games is an important area for strength and conditioning coaches to monitor as it facilitates for athletes to be ready to perform (11,13). Utilising athletic performance data in conjunction with self-rated reporting measures can help determine if in fact a player or team has recovered sufficiently or shown a trend towards recovery prior to a competitive match (11). Positive improvement in recovery variables can provide confidence in the effectiveness of recovery methods used and assist in determining the training schedule in order to positively manipulate the fitness-fatigue relationship (3).

Various methods of analysing the recovery of athletes have been reported in the literature and are available to the strength and conditioning coach. These include subjective, self-rated scales and perceived level of recovery questionnaires (11,12,13). Athletic performance measures during exercises such as the counter movement jump (CMJ) have also been analysed, predominantly utilising force plates to obtain kinetic data. (5,13,14). However, such equipment can be difficult to transport, requires continual calibration and is costly to purchase. A linear transducer can provide important information on CMJ variables in the assessment of athletic movements and due to its size and portability could serve as a valuable tool to assist strength and conditioning coaches, (8,10), and potentially enable the monitoring of recovery.

Previous studies have investigated the fatigue effects of competitive games in various sports (11,13,14) including Australian Rules Football (AFL) at the senior elite league level (5, 6). To the authors’ knowledge, however, there is yet to be a study investigating the recovery response in AFL players, specifically in players 18 years and under competing in the National Under 18s Championships. Australian Rules football is an extremely physically demanding and fatiguing sport where players participate in games time exceeding 120 minutes duration, covering large distances (~12-18km, position dependent) with many high intensity efforts performed at random times throughout the game (2,6,16). Hence, it would seem pertinent to analyse the fatigue effects of competitive matches in an Australian Rules Under-18’s National Championship and the subsequent recovery from these games.

The aim of this study was to analyse and compare two self-rated subjective measures of recovery; they being muscle soreness (MS) of the lower body, overall perceived total recovery (TR), and the performance measure of peak velocity (PV) obtained from a CMJ analysed with a linear transducer. Data collection occurred between rounds four and five of the Australian Football League Under-18’s National Championship, representing a four-day recovery analysis period between matches.

Evaluation of an Innovative Critical Power Model in Intermittent Vertical Jump

The aim of this study was to test if the critical power model can be used to determine the critical rest interval (CRI) between vertical jumps. Ten males performed intermittent countermovement jumps on a force platform with different resting periods (4.1 +/- 0.3 s, 5.0 +/- 0.4 s, 5.9 +/- 0.6 s). Jump trials were interrupted when participants could no longer maintain 95% of their maximal jump height. After interruption, number of jumps, total exercise duration and total external work were computed. Time to exhaustion (s) and total external work (J) were used to solve the equation Work = a + b . time. The CRI (corresponding to the shortest resting interval that allowed jump height to be maintained for a long time without fatigue) was determined dividing the average external work needed to jump at a fixed height (J) by b parameter (J/s). in the final session, participants jumped at their calculated CRI. A high coefficient of determination (0.995 +/- 0.007) and the CRI (7.5 +/- 1.6 s) were obtained. In addition, the longer the resting period, the greater the number of jumps (44 13, 71 28, 105 30, 169 53 jumps; p<0.0001), time to exhaustion (179 +/- 50, 351 +/- 120, 610 +/- 141, 1,282 +/- 417 s; p<0.0001) and total external work (28.0 +/- 8.3, 45.0 +/- 16.6, 67.6 +/- 17.8, 111.9 +/- 34.6 kJ; p<0.0001). Therefore, the critical power model may be an alternative approach to determine the CRI during intermittent vertical jumps.

Análise cinemática e cinética do salto vertical de crianças com transtorno do desenvolvimento da coordenação (TDC)

Due to motor difficulties, children with developmental coordination disorder (DCD) doesn't feel motivated to do physical activities, sometimes resulting in a decline of their physical fitness, but it isn't really known for sure the reasons that induct children with DCD to low performances in physical fitness tests, because a lot of tasks that are part of the battery of tests of physical performance are complex in the coordination and/or motor control point of view, like the vertical jump for example. Therefore, the objective of this study was to investigate the factors that induct children with DCD to low performances in physical fitness tests, especially in the vertical jump task. For that, cinematic (duration of the eccentrical phase, duration of the concentrical phase, shift of the mass center and velocity of the mass center), kinetic (potency peak and force peak) and vertical jump performance analysis in two conditions (with the use of arms and without it) were realized in a force platform. The results indicated that children with DCD show a lower performance compared to their peers with typical development (TD), due to a lower potency production

Effects of strength and power training on neuromuscular adaptations and jumping movement pattern and performance

Effects of strength and power training on neuromuscular adaptations and jumping movement pattern and performance. J Strength Cond Res 26(12): 3335-3344, 2012-This study aimed at comparing the effects of strength and power training (ST and PT) regimens on neuromuscular adaptations and changes on vertical jump performance, kinetics, and kinematics parameters. Forty physically active men (178.2 +/- 7.0 cm; 75.1 +/- 8.6 kg; 23.6 +/- 3.5 years) with at least 2 years of ST experience were assigned to an ST (n = 14), a PT (n = 14), or a control group (C; n = 12). The training programs were performed during 8 weeks, 3 times per week. Dynamic and isometric maximum strength, cross-sectional area, and muscle activation were assessed before and after the experimental period. Squat jump (SJ) and countermovement jump (CMJ) performance, kinetics, and kinematics parameters were also assessed. Dynamic maximum strength increased similarly (p < 0.05) for the ST (22.8%) and PT (16.6%) groups. The maximum voluntary isometric contraction increased for the ST and PT groups (p < 0.05) in the posttraining assessments. There was a main time effect for muscle fiber cross-sectional area (p < 0.05), but there were no changes in muscle activation. The SJ height increased, after ST and PT, because of a faster concentric phase and a higher rate of force development (p < 0.05). The CMJ height increased only after PT (p < 0.05), but there were no significant changes in its kinetics and kinematics parameters. In conclusion, neuromuscular adaptations were similar between the training groups. The PT seemed more effective than the ST in increasing jumping performance, but neither the ST nor the PT was able to affect the SJ and the CMJ movement pattern (e.g., timing and sequencing of joint extension initiation).

Differences in end range of motion vertical jump kinetic and kinematic strategies between trained weightlifters and elite short track speed skaters

The purpose of this investigation was to identify differences in end range of motion (ROM) kinetic and kinematic strategies between highly resistance and vertical jump-trained athletes and controls. Weightlifters (WL: n 4), short track speed skaters (STSS: n 5), and nonresistance-trained controls (C: n 6) performed 6 standing vertical squat jumps (SJ) and countermovement jumps (CMJ) without external resistance. Jump testing was performed using 3-dimensional marker trajectories captured with a 15-camera motion analysis system synchronized with 2 in-ground force plates. During SJ, there were large effects for the difference in time before toe off of peak vertical velocity between WL to STSS and C (ES: -1.43; ES: -1.73, respectively) and for the decrease between peak and toe off vertical velocity (ES: -1.28; ES: -1.71, respectively). During CMJ, there were large effects for the difference in time before toe off of peak vertical velocity between WL to STSS and C (ES: -1.28; ES: -1.53, respectively) and for decrease between peak and toe off vertical velocity (ES: -1.03; ES: -1.59, respectively). Accompanying these differences for both jump types were large effects for time of joint deceleration before toe off for all lower body joints between WL compared with C with large effects between WL and STSS at the hip and between STSS and C at the ankle. These findings suggest that the end ROM kinetic and kinematic strategy used during jumping is group-specific in power-trained athletes, with WL exhibiting superior strategies as compared with resistance- and jump-trained STSS.

Is nine weeks of complex training effective for improving lower body strength, explosive muscle function, sprint and jumping performance?

There is currently minimal evidence from training studies that document the effectiveness of complex training to elicitgains in explosive muscle function that are greater than those obtained from a more conventional approach. Over nineweeks of training, 20 recreationally trained athletes with a minimum of one year of resistance training experience wererandomly assigned to either a complex training group (n¼9) or a conventional training group (n¼11). In an attempt tocapitalise on muscle’s post-activation potentiation response, the complex training group performed all sets of ½ backsquats prior to sets of jumps squats, while the conventional training group performed jump squats prior to sets of ½ backsquats. Lower body explosive muscle function and jump performance improved significantly in both groups. The complextraining group’s improvement in running vertical jump performance was significantly greater than in the conventionalgroups. Sprint performance was not significantly improved in either training group.

Avaliação do perfil antropometrico e de força de jovens jogadores de polo-aquatico

Twelve athletes (13,9±1,1 years, 169,0±6,0 cm and 59,5±13,5 kg ofbody weight) were under went to anthropometric and body compositionassessments, and maximum concentric strength of lower limbs. The jumptest in the water was done by ‘boost’ and scaled to jump height. The resultsof strength (Leg Press 45: 157,1±43,3 kg; Leg Extension: 72,1±12,9 kg),anthropometry (circumferences of arm: 26,0±3,3 cm; thigh: 50,5±7,7 cm;shoulder: 96,0±8,0 cm, and diameter of elbow: 4,7±0,5 cm; wrist: 3,2±0,3cm; knee: 7,9±0,6 cm; bi-acromial: 37,5±3,8 cm; and bi-iliac: 25,4±4,3cm), BMI (20,7±4,0 kg/m²), and body composition (fat: 8,5±4,3%) were notrelated to the values of vertical jump performance (47,80 ? 4,35 cm), as didshowed for body height (0,595). Thus, athletes height was one able to influencethe jump performance by modifying it self, perhaps by maturity.