The average power with the full squat with 70kg also showed significant positive correlations with the sprint times. The CMJ height has been greatly used to access lower body power in soccer players (Wisloff, 1998; Helgerud, 2001; N��?ez, 2008; Ronnestad, 2008). Nevertheless, to our knowledge, only two previous studies toward (Gorostiaga, 2004; L��pez-Segovia, 2010) have used loaded countermovement jump (CMJL) exercise for testing lower limb power in this population. Unfortunately, these authors (Gorostiaga, 2004; L��pez-Segovia, 2010) did not include sprint evaluations in their studies. Different factors such as lower reliability of testing at very short distances, the static start position in the sprint test and the location of the first photoelectric cells (30 cm behind start in these two studies) could explain the lack relationship reported between CMJ and time at 10m.
Although, the relationship obtained between the vertical jump and 30m sprint time (present study: r= ?0.55; p<0.05 vs. r= ?0.60; p<0.01) was similar to the study of Wisloff (2004), the relationships observed between the vertical jump and last running meters are consistent with the results perceived with loaded jump, given a similarity of muscle action in both types of jumps. Significant association between peak power during loaded CMJ and later stages of the sprint (r=?0.544 to ?0.611; p��0.05) were obtained. The T10�C30 and T20�C30 were significantly related with peak power observed in the CMJL exercise with 20, 30, and 40kg external load.
Cronin and Hansen (2005) observed similar results in professional rugby players between loaded (30kg) vertical jump height and 5m, 10m, and 15m sprint times. The higher relationships (R2= 41�C62%) observed in the present study were perceived with the longer distances rather than the initial run. As running velocity approaches maximum, those strength measures that require force to be produced at high velocities have been reported to be significantly related to sprint performance (Wilson, 1995; Young, 1995; Nesser, 1996). Wilson (1995) reported a significant relationship between force at 30 ms in a concentric squat jump and 30m sprint time (r= 0.62). Nesser (1996) claimed significant correlations between 40m sprint time and peak isokinetic torque at a velocity of 7.85 rad/s for the hip and knee extensors and knee flexors (r= 0.54 to 0.61).
We agree with the assertion that results show a slight tendency of increased relationships such as velocity and distance increased (Table 2). Moreover, data showed that power output during the vertical jump with 20kg best explained sprint performance. This parameter was also significantly correlated with all split speed measurements, including the first sprint stages. Although correlations do not signify causation, CMJ training with light loads could be important Anacetrapib to improve sprint performance in soccer player��s under-21.
6.0 software package was employed for the analysis of the results. Spearman��s selleck chem rank correlation coefficient and Mann-Whitney U-test were also used during the study. Results Table 2 presents the values of coefficients that determine the fight. Table 2 Characteristics of the indexes that determine activity, effectiveness and the rank of study participants (n=10) The analysis of the activity index (WA) revealed that contestants performed from 1.0 to 3.5 technical actions per fight, but a comparison of the activity within the individual periods of competition revealed a considerable difference. The studied group included both judokas whose activity increased in the second part of fight (minimum value of RWA =?1.7) and those who performed fewer actions (maximum value of RWA=0.5). The mean RWA (?0.
5) suggests a tendency for increased activity in the second part of fight. The mean value of the effectiveness index (WS) in the studied group amounted to 3.4. Similarly to the activity index, individual judokas varied considerably (minimum = 2.4 points, maximum = 6.8 points). The analysis of the RWS value (0.8 points) revealed a tendency towards a decline in the mean value of the points given in the second part of the fight. However, in individual cases, contestants demonstrated a considerable rise in effectiveness (?3.2) in the 3rd and 4th minutes of match. Although differentiation occurred, on average, the level of achievement (PO) was 3.3 with the lowest participant at 1 point and the highest participant at 6 points. Individual cases reveal that the biggest differentiation amongst the judokas was observed in movement (test No.
17, V=75.9), spatial orientation (test No. 25, V=73.4) and visual-motor coordination, (test No. 23, V=69.3). Reaction time varied the least among the group as follows: minimum reaction time to visual stimulus (test No. 3, V=6.7), mean reaction time to visual stimulus, minimum reaction time to auditory stimulus (tests No. 4 and 6, V=8.7) and also minimum reaction time and mean complex reaction time (tests No. 9 and 10, V=9.6). Table 4 compares statistically significant values of Spearman��s rank correlation coefficients calculated between the results of coordination tests and the sports performance in the studied group of contestants. Table 4 Statistically significant (p<0.
05) values of rank correlation coefficient calculated between the results of coordination tests and sports performance in the studied group of contestants. (n=10) Analysis of the value of Spearman��s R coefficient for WA revealed that its value was negatively correlated to the ability to differentiate movements (high correlation, Spearman��s coefficient: R=?0,7). While the examination of WA1 (activity index for the first part Anacetrapib of match) revealed a positive correlation to mean reaction time (Spearman��s R coefficient=0.65) and maximum reaction time (Spearman��s R coefficient=0.
, 2005) using different types of hand dynamometers. Particularly, Espana-Romero et al. (2008) reported high reliability (ICC = 0.97 �C 0.98) of the handgrip strength test in 6�C12 year-old children, using the Takey dynamometer. http://www.selleckchem.com/products/ganetespib-sta-9090.html Excellent test-retest reliability (r = 0.96 �C 0.98) of handgrip strength have been also showed in untrained adolescents (14�C17 years-old; Ruiz et al., 2006). In addition, Langerstrom et al. (1998) and Ruiz-Ruiz et al. (2002) found high reliability (r = 0.91 �C 0.97) of the handgrip strength test in healthy adults using the Grippit and Takei dynamometers, respectively. The results of this study are also, in accordance with those by Coelho e Silva et al. (2008; 2010) in young basketball players (14�C15.9 years-old and 12�C13.9 years-old, respectively) that reported high reliability (r = 0.
99) of handgrip strength using the Lafayette hand dynamometer. Table 3 Test-retest reliability of maximal handgrip strength in healthy children, adolescents and adults Our results support earlier findings that showed non-significant differences in handgrip strength between test and retest values (Espana-Romero et al., 2008; 2010a). In contrast, Clerke et al. (2005) found small but significant differences in handgrip strength between test and retest, in 13 to 17 year-old adolescents. The absence of warm-up or familiarization prior to testing in the above study may account for the differences in handgrip strength between test and retest measurements. Indeed, Svensson et al.
(2008), who also found differences in handgrip strength between test and retest suggested that children may learn over the trials a better technique or accomplish to squeeze harder. Therefore, the authors recommended a familiarization session and three maximal trials during the main testing. Reliability and age-effect Only a few studies addressed the issue of age-effect on reliability of handgrip strength in untrained participants (Table 4). The results of our study are in line with those of Espana-Romero et al. (2010a) who examined the reliability of the handgrip strength test in untrained children (6�C11 years-old) and adolescents (12�C18 years-old) using the Takey dynamometer and found high reliability in both age-groups. Moreover, Molenaar et al. (2008) compared the reliability of handgrip strength among three age-groups of untrained children (4�C6, 7�C9, and 10�C12 years old) using two different dynamometers (Lode dynamometer vs.
Martin vigorimeter), and reported no clear age-effect on reliability for both dynamometers. GSK-3 Table 4 Test-retest reliability of maximal handgrip strength at different age-group. In contrast, Svensson et al. (2008) compared the reliability of the handgrip strength test among 6, 10 and 14 year old untrained children using the Grippit dynamometer, and showed greater reliability in 6 and 14 year old (ICC = 0.96) compared to 10 year old children (ICC = 0.78).
55 m/s were excluded. So finally, the measurements were carried out on a sample of 27 women and selleckchem 27 men. For each of the subjects we registered 20 gait cycles (40 steps). After hearing the signal the subject covered a distance of about 50 meters. From the collected data we were able to identify kinematic variables describing the temporal and phasic structure of locomotion, as well as the angular changes in the major joints of the lower limbs (ankle, knee and hip) in the sagittal plane. The values of these parameters were calculated separately for the left and right leg, which made it possible to determine the size of the differences and was the basis for assessing gait asymmetry. Body segments were defined by means of 39 reflective markers having a diameters of 25 mm attached to the head, trunk, pelvis, arms and legs.
Kinematic data were divided into individual gait cycles for each side of the body. A gait cycle was defined from heel strike to subsequent heel strike. Data for each cycle were normalized (0% GC �C 100% GC). For the purpose of analysis, the functional phases of gait were subdivided into (according to Perry, 1992) LR-loading response (10% GC), MST-mid stance (20% GC), TST-terminal stance (20% GC), PSW-pre swing (10% GC), ISW-initial swing (10% GC), MSW-mid swing (15% GC), and TSW-terminal swing (15% GC). To assess the normal distribution of acquired data we used the Shapiro-Wilk test. The student��s t test for independent groups was used to examine the statistical significance of differences between mean values of variables obtained during gait.
To determine the average level of diversification of the parameters in terms of gender in the characteristic phases of a standardized gait cycle, which is described below, we applied a two-way analysis of variance ANOVA with repeated measurements. To evaluate the level of gait asymmetry in the angular data, the authors employed a relative asymmetry index (RAI): RAI=X��Y100%,where: (1) – the average difference between the values noted for the right and left limbs in a given phase of the gait cycle (LR, MST, etc.) Y – total range of motion of the angular changes in the given phase (absolute value of the difference between the largest and the smallest angles for a given phase of the gait cycle).
The average difference () in successive phases of gait was calculated according to the following formula: X��=��i=li=n|Ri-Li|%GC,where: (2) R, L- instantaneous value of the angle of individual joints in the right and left lower limb, % GC – relative duration of the given phase in the gait cycle (number). Consistently, in accordance Drug_discovery with the adopted symbols and the way of their determination, the described equation for LR phase (10% GC) was as follows: X��LR=��i=li=10|Ri-Li|10. (3) Results Tables 2 and and33 show the values of selected kinematic parameters of gait, both in terms of gender and the side of the body.
Figure 1 Clinical appearance of the same lesion. The overlying mucosa despite was normal and there was not any sign or symptom. To categorize the canal system in MBR (mesiobuccal root) mesio-distal and bucco-palatal radiographs were obtained. The size 0.8 files were placed into the main mesiobuccal and second mesiobuccal canal. The teeth with no access to the apex were eliminated. Before photographing of pulp chambers millimetric glass scale was placed in order to make measurements to characterize the geometrical location of MB2 canals. The main mesiobuccal, palatal and MB2 canal orifices were marked on the millimetric glass scale. The main mesiobuccal canal and the palatal orifices were connected through a line MB-P and in addition to this line a perpendicular line was drawn from the MB2 canal orifice to the M-P line.
The main mesiobuccal canal was accepted as the origin and the vertical distance from MB2 to MB-P line was measured, as described by G?rduysus et al16 (Figure 2). The images were analyzed by Image-Proplus 4.0 software to measure the relationship between MB2 canal and other canals. Figure 2 On the millimetric glass scale, measurements were made to characterize the geometrical location of MB2 canals. MB: mesiobuccal canal orifice, MB2: second mesiobuccal canal orifice, P: palatal canal orifice. RESULTS The second mesiobuccal canal was found in 78% of the 110 maxillary molars and in 17 (19.8%) of these MB2 canals it was accessible to the apex. The teeth with no access to the apex were discarded and of the remaining 17, 3 (17.6%) had a Vertucci Type IV and 14 (82.
4%) were Vertucci Type II canal system. With the unaided vision 58 MB2 canal orifices and after evaluation with the dental loup an additional 17 MB2 canal orifices were detected. 68% of MB2 canals were located by using methods and 11 additional MB2 canals were identified with the use of the DOM (Figure 1). In 65 (75.6%) molars the MB2 canal orifices was located 0.87 mm distally and 1.73 mm palatally to the main mesiobuccal canal and in the remaining 21 (24.4%) molars was 0.72 mm mesially and 1.86 mm palatally as represented in the Figure 3. Figure 3 The location of MB2 canal orifices to the main mesiobuccal canal. The triangle drawn with the red color shows the standard endodontic access cavity and the rhomboidal shape drawn with the green color shows alternative endodontic access cavity.
DISCUSSION In the present study it was found that 78.18% of maxillary first molar possessed a second mesiobuccal canal. This is consistent with the findings of Burhley et al17 but higher than that reported by Sempira Cilengitide and Hartwell.6 In the study of Sempira and Hartwell6 the second mesiobuccal canal had to be negotiated and obturated either separate from MB or within 4 mm of the apex. If two separate orifices blended into a single canal coronally during instrumentation, it was not considered to be a separate canal.
, 2006). The technique of Trichostatin A (TSA) shooting from higher heights allowed increasing the chance of obtaining a successful ball possession. In particularly, the best players exhibited excellent technical abilities in its use. Also, the goalkeepers do not carry sticks and can use their legs and hands to stop the ball; therefore, the offensive players have to shoot with higher accuracy when trying to score. In fact, the goalkeeper has a great importance in stops efficiency, in particular Prieto and P��rez (2011) found that elite floorball goalkeepers can stop up to 80% shots per game (Prieto and P��rez, 2011). In HIGH vs. LOW game, the increased chance to obtain successful ball possessions was related with the use of longer ball possessions with more participants.
The best teams use more offensive strategies than lower level teams, and this has consequences in creating more shooting situations (Marcelino et al., 2011). Most of the goals in field-hockey occur from repossession obtained out of the goal area from free hits and interceptions (Sunderland et al., 2006). In fact, the best teams may use defensive pressure in attack half court and worst teams have technical and tactical limitations that generate more turnovers. The technique of shooting of backhand and push (forehand drive) reduced the chance to obtain a successful ball possession. In particular, the push technique was more common in defensive players, as it needs more time and space and they usually use this form as a long distance shot (Paavilainen, 2007).
The use of this type of shot does not increase the effectiveness of possessions during organized set plays, this result may reflect that worst teams try to shoot from long distances with this technique. The most effective techniques to score a goal in field hockey are a hit or a deflection, with a reduced percentage of goals scored from a push shot (Sunderland et al., 2006). Conversely, the backhand technique is a difficult skill that needs a higher level of expertise and practice, and is less used by lower level players. The differences of team quality also reflected the influence of defensive pressure. The use of high or intermediate defensive pressure previous to the shot increased ball possession effectiveness. As was argued, the best teams are more prepared technically and tactically and they can solve these defensive situations with higher efficacy.
The Cilengitide low level teams may show less concentration during ball possessions on the open player or the goal when they have high or intermediate defensive pressures, what reduces the effectiveness of last passes and shots. In fact, when field-hockey players were tested in specific game situations, the high level players obtained better performances and used less time to solve the tests than lower level players (Nair and Bunker, 2002). There are different zones of the offensive half court that increased the ball possession effectiveness in LOW vs.