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Effects of Concurrent Strength and High-Intensity Interval Training on Fitness and Match Performance in Water-Polo Players

Abstract

The purpose of the study was to examine changes in performance and match-induced fatigue over a 27-week training period. Eight national-level water-polo players performed a 5 x 200 m swimming test to calculate velocities corresponding to blood lactate concentration of 4.0, 5.0 and 10.0 mmol.l-1 at three testing periods: i) baseline, ii) end of the pre-season (8 weeks of 4 x 4 min swimming bouts), iii) end of the in-season (8 weeks of 8 x 20 m swimming sprints). During each testing period, four competitive matches were played and repeated sprints (8 x 20 m), 400 m swimming, and shooting accuracy were evaluated at the pre- and post-match. Repeated sprint tests were also conducted at mid-game. Analysis of variance for repeated measures was used to detect changes among training periods and within games. Swimming velocities corresponding to 4.0, 5.0 and 10.0 mmol.l-1 were increased after the pre-season by 9%, 7.7%, and 6.7% (p < 0.01) and decreased following the in-season compared to the pre-season by 8.9%, 7.0% and 3.3% (p < 0.01), respectively. Pre-match repeated sprints and 400 m performance were improved after the pre-season by 4.3% and 3.8% (p < 0.01) and decreased by ~3% after the in-season compared to the pre-season (p < 0.01). Mid- and post-match repeated sprint performance was improved after the pre-season by 4.8 ± 1.4% and 4.4 ± 1.1% and remained unchanged after the in-season compared to the pre-season. Post-match 400 m speed was improved by 3.2% after the pre-season (p < 0.01) and decreased by 2.8% after the in-season (p = 0.04).Pre-season training improved players’ aerobic endurance and performance. Intensified in-season training decreased aerobic power, endurance, and pre-match performance while maintaining match repeated sprint performance.

Open access
Effects of Slackline Training on Acceleration, Agility, Jump Performance and Postural Control in Youth Soccer Players

Abstract

The goal of this study was to assess the effects of a supervised slackline training program in a group of soccer players. Thirty-four male division I under-19 players (16.64 ± 0.81 years) agreed to participate in the study. They were randomly divided into an experimental group (EG) and a control group (CG). The first group (EG) followed a 6-week supervised slackline training program (3 sessions/week; 5-9 min/session), while the CG performed only regular soccer training. Several variables were assessed in all participants: acceleration (20-m sprint test), agility (90º turns test), jump performance (squat jump, countermovement jump), and postural control (Center of Pressure ( CoP) testing: length, area, speed, Xmean, Ymean, Xspeed, Yspeed, Xdeviation, Ydeviation). Ratings of perceived exertion and local muscle ratings of perceived exertions were also recorded after each slackline training session. At post-tests, there was a significant increase only in the EG in acceleration, agility, squat jump and countermovement jump performance, as well as several CoP variables: area in the bipedal support on a firm surface, and length, area and speed in the left leg on a firm surface. The program was rated as “somewhat hard” by the players, while quadriceps, gastrocnemius and tibialis anterior were the most exerted muscles while slacklining. In conclusion, slackline training can be an effective training tool for young, high-level soccer players.

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Effects of the Performance Level and Race Distance on Pacing in Ultra-Triathlons

Abstract

The aim of this study was to examine the effects of the performance level and race distance on pacing in ultra-triathlons (Double, Triple, Quintuple and Deca), wherein pacing is defined as the relative time (%) spent in each discipline (swimming, cycling and running). All finishers (n = 3,622) of Double, Triple, Quintuple and Deca Iron ultra-triathlons between 1985 and 2016 were analysed and classified into quartile groups (Q1, Q2, Q3 and Q4) with Q1 being the fastest and Q4 the slowest. Performance of all non-finishers (n = 1,000) during the same period was also examined. Triple and Quintuple triathlons (24.4%) produced the highest rate of non-finishers, and Deca Iron ultra-triathlons produced the lowest rate (18.0%) (χ2 = 12.1, p = 0.007, φC = 0.05). For the relative swimming and cycling times (%), Deca triathletes (6.7 ± 1.5% and 48.8 ± 4.9%, respectively) proved the fastest and Double (9.2 ± 1.6% and 49.6 ± 3.6%) Iron ultra-triathletes were the slowest (p < 0.008) with Q4 being the fastest group (8.3 ± 1.6% and 48.8 ± 4.3%) and Q1 the slowest one (9.5 ± 1.5% and 50.9 ± 3.0%) (p < 0.001). In running, Double triathletes were relatively the fastest (41.2 ± 4.0%) and Deca (44.5 ± 5.4%) Iron ultra-triathletes the slowest (p < 0.001) with Q1 being the fastest (39.6 ± 3.3%) and Q4 the slowest group (42.9 ± 4.7%) (p < 0.001). Based on these findings, it was concluded that the fastest ultra-triathletes spent relatively more time swimming and cycling and less time running, highlighting the importance of the role of the latter discipline for the overall ultra-triathlon performance. Furthermore, coaches and ultra-triathletes should be aware of differences in pacing between Double, Triple, Quintuple and Deca Iron triathlons.

Open access
Ending MMA Combat, Specific Grappling Techniques According to the Type of the Outcome

Abstract

This study compared grappling motor actions of male mixed martial arts (MMA) athletes considering outcome types from Ultimate Fighting Championship ( UFC) bouts. A validated protocol of technical-tactical analysis was utilized as in previous studies addressing MMA performance analysis, and Kruskall Wallis and U Mann-Whitney tests were applied to compare effects of types of outcome decisions (Split vs. Unanimous Decision vs. Knockout-KO/Technical-knockout-TKO vs. Submission). Unanimous Decision showed higher frequencies of takedowns attempted/round than KO/TKO and Submission outcomes (p ≤ 0.05; 1.9 ± 1.9 vs. 1.3 ± 1.4 vs. 1.0 ± 1.1 attempts). Bouts with Split Decision demonstrated higher takedowns/round than bouts ended by Submission (p = 0.048; 0.4 ± 0.7 vs. 0.2 ± 0.6 attempts). TKO/KO showed lower values of sweeps/round (p = 0.008, 0.0 ± 0.0 vs. 0.1 ± 0.3 attempts) and takedowns attempted/round (p = 0.014, 1.3 ± 1.4 vs. 2.0 ± 1.6 attempts) than bouts ending by Split Decision. The Submission outcome showed a higher frequency of submissions attempted/round than KO/TKO and Unanimous Decision (p ≤ 0.041, 0.3 ± 0.7 vs 0.2 ± 0.5 vs 0.2 ± 0.5). These results show a large specificity in the type of grappling attack/situation according to the strategy to end the combat. These results also show that the grappling strategy and tactics are variable depending on the strengths and weaknesses of the athletes, and can be used by coaches and athletes to develop specific training programs.

Open access
Force-Velocity Relationship in the Countermovement Jump Exercise Assessed by Different Measurement Methods

Abstract

This study aimed to compare force, velocity, and power output collected under different loads, as well as the force-velocity (F-V) relationship between three measurement methods. Thirteen male judokas were tested under four loading conditions (20, 40, 60, and 80 kg) in the countermovement jump (CMJ) exercise, while mechanical output data were collected by three measurement methods: the Samozino's method (SAM), a force platform (FP), and a linear velocity transducer (LVT). The variables of the linear F-V relationship (maximum force [F0], maximum velocity [V0], F-V slope, and maximum power [P0]) were determined. The results revealed that (1) the LVT overestimated the mechanical output as compared to the SAM and FP methods, especially under light loading conditions, (2) the SAM provided the lowest magnitude for all mechanical output, (3) the F-V relationships were highly linear either for the SAM (r = 0.99), FP (r = 0.97), and LVT (r = 0.96) methods, (4) the F-V slope obtained by the LVT differed with respect to the other methods due to a larger V0 (5.28 ± 1.48 m·s-1) compared to the SAM (2.98 ± 0.64 m·s-1) and FP (3.06 ± 0.42 m·s-1), and (5) the methods were significantly correlated for F0 and P0, but not for V0 or F-V slope. These results only support the accuracy of the SAM and FP to determine the F-V relationship during the CMJ exercise. The very large correlations of the SAM and LVT methods with respect to the FP (presumed gold-standard) for the mean values of force, velocity and power support their concurrent validity for the assessment of mechanical output under individual loads.

Open access
Gross Efficiency and the Relationship with Maximum Oxygen Uptake in Young Elite Cyclists During the Competitive Season

Abstract

This study assessed gross efficiency (GE) during a single competitive season and determined the relationship between GE and maximum oxygen uptake (V̇O2max) in young elite cyclists (n = 15, 20.1 ± 1.4 yrs, 177.5 ± 5.7 cm, 68.3 ± 6.2 kg, 45.2 ± 7.5 mm of six skinfolds) during a competitive season. Participants completed at two occasions (T1 = April; T2 = July), a progressive bike protocol (initial intensity = 100 W, 35 W increments every 3 min) until volitional exhaustion to assess V̇O2max and submaximal variables. A single capillary blood sample was drawn from the left earlobe immediately after completion of each exercise load to determine lactate thresholds. Cyclists’ GE was calculated as ([work accomplished/energy expended] x 100). No significant differences were obtained in GE at any workload between T1 and T2 or in the mean GE between T1 (19.3%) and T2 (19.4%) testing (p = 0.93). No significant association was found between mean GE and V̇O2max at either T1 (r = -0.28, p = 0.30), or T2 (r = -0.27, p = 0.32). GE of young elite cyclists might not vary during the most important phase of the training season and GE was not related to V̇O2max. A lower accumulated volume and intensity of training of these cyclists may account for their lower GE in comparison to older professional cyclists and might not have been enough to foster higher increases of GE in cyclists with lower V̇O2max.

Open access
The Incidence and Occurrence of Injuries to Junior Rugby League Players in a Tropical Environment

Abstract

This study investigated the effect of the environment, jersey color and ground conditions on injury rates in junior rugby-league players in a tropical environment. Injury, environment and ground condition data were collected during each game, over one season (n = 12 rounds). The study investigated three teams (n = 64): one under-16 team in striped jerseys and two under-14 teams in black and orange jerseys. The injury rates for the under-16 team (83.3/1000 hrs) were higher than for the under-14 teams in black (69.9/1000 hrs) and orange (59.9/1000 hrs) jerseys. In the under-16 team, a negative correlation (r = -0.66, p < 0.05) was found between players’ injuries and heat index, while in the under-14 team in black jerseys, a positive correlation was observed (r = 0.90, p < 0.01), although in the under-14 team in orange, no significant correlation was found (r = 0.140, p > 0.05). In the under-14 team in black, a significant correlation (r = 0.80, p < 0.01) between players’ injuries and the temperature was observed. However, no correlations were found with any other variables per group (p > 0.05) and injury rates were not different between the teams (p > 0.05). While ground conditions had no effect on injury rates, it appears that the heat acted as a protection against injury for teams with striped and orange jerseys. However, black jerseys may put players at an increased risk of injury during hot and humid day games.

Open access
Is Playing Soccer More Osteogenic for Females Before the Pubertal Spurt?

Abstract

The aims of this study were to assess bone mass in children and adolescent soccer players and to evaluate the influence of both gender and pubertal status on bone mass. A total of 110 soccer players (75 males / 35 females; 12.73 ± 0.65 / 12.76 ± 0.59 years) participated in this cross-sectional study. They were divided into two groups according to their pubertal status. Bone and lean masses were measured with Dual-energy X-ray Absorptiometry. An independent t-test and an adjusted by subtotal lean and training experience multivariate analysis of covariance were used to analyse the differences in bone mass values between genders and maturity status. Female soccer players presented higher bone mass values than their male counterparts in most of the measured weight-bearing sites. Moreover, when stratifying by pubertal status, peripubertal and postpubertal females had higher subtotal body and lumbar spine bone mass than males. Comparing between pubertal status groups before adjustment, both male and female postpubertal players showed higher bone mass than their pubertal counterparts. After adjusting, these differences disappeared and, in fact results were inverted as bone mass at the femoral neck was higher in both male and female peripubertal soccer players than in postpubertal players. Bone mass seems to be more intensely stimulated by playing soccer in female than male players, particularly in the lumbar spine. The results of peripubertal players showing higher bone mass at the femoral neck after adjusting suggest that playing soccer during the peripubertal stage could be an effective activity to achieve optimal bone mass values.

Open access
Jump Performance During Official Matches in Elite Volleyball Players: A Pilot Study

Abstract

The purpose of this pilot study was to assess the types and intensity of the jumps that professional male volleyball players executed. Seven male elite volleyball players participated in this study. The sample was composed of 1599 jumps performed in 15 sets of five official matches of the regular season of a professional team. A descriptive pilot study design was implemented to analyze the types of jumps and jump heights by particular playing positions (outside hitters, setter, and middle blockers). The jump height was recorded using an inertial measurement device. No significant differences in the heights of jumps were found between the sets of the matches. Different players’ roles had different frequencies for different types of jumps and jump intensities. The data provide reference values of the type of jumps performed, their frequency, and intensity by particular playing positions in competition. The results confirm the need to individualize the practice and training of volleyball players according to the players’ roles. Extensive studies are needed to provide more information about repeated jump ability in volleyball players.

Open access
Mouth Rinsing Cabohydrates Serially does not Improve Repeated Sprint Time

Abstract

Sensing carbohydrates via the oral cavity benefits performance outcomes during brief high intensity bouts of exercise. However, the extent to which carbohydrates need to be present in the oral cavity to influence sprint performance is less understood. The purpose of this study was to determine if serial increases in carbohydrate rinse time across sprint sets attenuates increases in sprint time compared to no serial increases in carbohydrate rinse time across sprint sets. Fifteen sprint trained participants completed three repeated anaerobic sprint tests (RAST), 3 sets of 6 x 35-m sprints, under two different carbohydrate mouth rinsing (CMR) conditions; (1) rinsing for only 5 seconds (s), and (2) rinsing for 5 s, 10 s and 15 s (serial rinse). Prior to a RAST, participants provided perceived recovery status (PRS) and perceived feeling of arousal (FAS). Upon completion of each individual sprint, participants gave a rating of perceived exertion (RPE). A lactate sample was taken upon completion of each individual sprint set and after all 3 RASTs a session rating of perceived exertion (S-RPE) was measured. There were no significant differences in peak (p = 0.18) and average sprint time (p = 0.41). There were no significant differences in perceptual measures: RPE, PRS, FAS, S-RPE or for blood lactate concentration between CMR conditions. Overall, serial rinsing resulted in changes that were most likely trivial, but showed a 50% chance in perceiving a sprint session as less difficult. Rinsing carbohydrates in a serial manner between repeated sprint sets produces trivial changes of sprint speed and perceptual measures from sprint performance.

Open access