Strength and power predictors of sports speed

For many sporting activities, initial speed rather than maximal speed would be considered of greater importance to successful performance. The purpose of this study was to identify the relationship between strength and power and measures of first-step quickness (5-m time), acceleration (10-m time), and maximal speed (30-m time). The maximal strength (3 repetition maximum [3RM]), power (30-kg jump squat, countermovement, and drop jumps), isokinetic strength measures (hamstring and quadriceps peak torques and ratios at 60 degrees .s(-1) and 300 degrees .s(-1)) and 5-m, 10-m, and 30-m sprint times of 26 part-time and full-time professional rugby league players (age 23.2 +/- 3.3 years) were measured. To examine the importance of the strength and power measures on sprint performance, a correlational approach and a comparison between means of the fastest and slowest players was used. The correlations between the 3RM, drop jump, isokinetic strength measures, and the 3 measures of sport speed were nonsignificant. Correlations between the jump squat (height and relative power output) and countermovement jump height and the 3 speed measures were significant (r = -0.43 to -0.66, p < 0.05). The squat and countermovement jump heights as well as squat jump relative power output were the only variables found to be significantly greater in the fast players. It was suggested that improving the power to weight ratio as well as plyometric training involving countermovement and loaded jump-squat training may be more effective for enhancing sport speed in elite players.     

Movement Demands of Elite U20 International Rugby Union Players

The purpose of this study was to quantify movement demands of elite international age grade (U20) rugby union players during competitive tournament match play. Forty elite professional players from an U20 international performance squad were monitored using 10Hz global positioning systems (GPS) during 15 international tournament matches during the 2014/15 and 2015/16 seasons. Data on distances, velocities, accelerations, decelerations, high metabolic load (HML) distance and efforts, and number of sprints were derived. Data files from players who played over 60 min (n = 161) were separated firstly into Forwards and Backs, and more specifically into six positional groups; FR—Front Row (prop & hooker), SR—Second Row, BR—Back Row (Flankers & No.8), HB—Half Backs (scrum half & outside half), MF—Midfield (centres), B3 –Back Three (wings & full back) for match analysis. Analysis revealed significant differences between forwards and backs positions. Backs scored higher on all variables measured with the exception of number of moderate accelerations, decelerations (no difference). The centres covered the greatest total distance with the front row covering the least (6.51 ± 0.71 vs 4.97 ± 0.75 km, p < 0.001). The front row also covered the least high speed running (HSR) distance compared to the back three (211.6 ± 112.7 vs 728.4 ± 150.2 m, p < 0.001) who covered the most HSR distance, affirming that backs cover greater distances but forwards have greater contact loads. These findings highlight for the first time differences in the movement characteristics of elite age grade rugby union players specific to positional roles.     

Physiological and anthropometric correlates of tackling ability in junior elite and subelite rugby league players

This study investigated the tackling ability of junior elite and subelite rugby league players, and determined the relationship between selected physiological and anthropometric characteristics and tackling ability in these athletes. Twenty-eight junior elite (mean ± SD age, 16.0 ± 0.2 years) and 13 junior subelite (mean ± SD age, 15.9 ± 0.6 years) rugby league players underwent a standardized 1-on-1 tackling drill in a 10-m grid. Video footage was taken from the rear, side, and front of the defending player. Tackling proficiency was assessed using standardized technical criteria. In addition, all players underwent measurements of standard anthropometry (stature, body mass, and sum of 7 skinfolds), acceleration (10-m sprint), change of direction speed (505 test), and lower body muscular power (vertical jump). Junior elite players had significantly greater (p < 0.05) tackling proficiency than junior subelite players (65.7 ± 12.5 vs. 54.3 ± 16.8%). Junior elite players tended to be taller, heavier, leaner, and have greater acceleration, change of direction speed, and muscular power, than the junior subelite players. The strongest individual correlates of tackling ability were acceleration (r = 0.60, p < 0.001) and lower body muscular power (r = 0.38, p < 0.05). When multiple linear regression analysis was performed to determine which of the physiological and anthropometric characteristics predicted tackling ability, fast acceleration was the only variable that contributed significantly (r2 = 0.24, p < 0.01) to the predictive model. These findings demonstrate that fast acceleration, and to a lesser extent, lower body muscular power contribute to effective tackling ability in junior rugby league players. From a practical perspective, strength and conditioning coaches should emphasize the development of acceleration and lower body muscular power qualities to improve tackling ability in junior rugby league players.     

Muscle cross-sectional area and torque in resistance-trained subjects

Eight elite male bodybuilders (MB), five elite female bodybuilders (FB), eight male control (MC), and eight female control recreational weight-trainers (FC) performed maximal elbow flexions on an isokinetic dynamometer at velocities between 1.02 and 5.24 rad.s-1, from which peak torque (PT) was measured. Elbow flexor cross-sectional area (CSA) was measured by computed tomographic scanning. Flexor CSA.lean body mass-1 ratios were greater in MB than in other subject groups. Correlations of PT were positively related to CSA but negatively to CSA.lean body mass-1 and to PT.CSA-1. PT.CSA-1 at low-velocity contractions were greater in MC and FC than in MB and FB groups, suggesting a training effect. The velocity-associated declines in torque between velocities of 1.02 and 5.24 rad.s-1 averaged 28.4 +/- 0.9% and were statistically identical in men and women among the subject groups, suggesting that neither gender nor training had affected this variable.     

Do skill-based conditioning games offer a specific training stimulus for junior elite volleyball players?

This study investigated the specificity of skill-based conditioning games and compared the effectiveness of skill-based conditioning games and instructional training for improving physical fitness and skill in junior elite volleyball players. Twenty-five junior volleyball players (mean age +/- SE, 15.6 +/- 0.1 years) participated in this study. Heart rate data were collected on all players during the Australian Junior Volleyball Championships. After the competition, players were randomly allocated into a skill-based conditioning games group (n = 12) or an instructional training group (n = 13). Each player participated in a 12-week training program that included 3 organized court training sessions per week. No significant differences (P > 0.05) were detected between competition and skill-based conditioning games for the percentage of time spent in low-intensity, moderate-intensity, and high-intensity activities. Skill-based conditioning games induced improvements in vertical jump, spike jump, speed, agility, upper-body muscular power, and estimated maximal aerobic power, whereas technical instruction improved only spike jump and speed. Conversely, instructional training induced meaningful improvements in all measurements of skill, whereas improvements in technical skill after skill-based conditioning games were uncommon and typically small. The results of this study show that skill-based conditioning games offer a specific training stimulus to simulate the physiological demands of competition in junior elite volleyball players. Although the improvements in physical fitness after training were greater with skill-based conditioning games, instructional training resulted in greater improvements in technical skill in these athletes. These findings suggest that a combination of instructional training and skill-based conditioning games is likely to confer the greatest improvements in fitness and skill in junior elite volleyball players.     

Development of muscle strength in relation to training level and testosterone in young male soccer players.

Isometric and functional strength of ninety-eight 11-yr-old male soccer players at an elite (E) and nonelite (NE) level were determined (3-4 times) through a 2-yr period, and the changes were related to growth and maturation. The initial isometric strength for extension with dominant leg [1,502 +/- 35 (E) vs. 1,309 +/- 39 (NE) N], extension with nondominant leg (1,438 +/- 37 vs. 1,267 +/- 45 N), extension with both legs (2,113 +/- 76 vs. 1,915 +/- 72 N), back muscles (487 +/- 11 vs. 414 +/- 10 N), abdominal muscles (320 +/- 9 vs. 294 +/- 8 N), and handgrip (304 +/- 10 vs. 259 +/- 8 N) increased by 15-40% during the period. Broad jump increased (P < 0. 05) by 15 (E) and 10% (NE). The E players had higher (P < 0.05) initial isometric strength and broad jump performance compared with NE players, and differences were maintained throughout the period (multiple ANOVA for repeated measures) also when adjustment was made for age, dimensions, testosterone, and insulin-like growth factor I (generalized estimating equations analyses). The development of strength for both E and NE players together was significantly (P < 0. 001) related to changes in serum testosterone concentrations. The present data indicate that testosterone is important for development of strength in young boys and that, independent of serum testosterone concentration, E players have developed greater muscle strength compared with NE players.     

Pure acceleration is the primary determinant of speed to first-base in major-league baseball game situations

The purposes of this research were to (a) quantify interval sprint times between Home-Plate and the Foul-Line and the Foul-Line and First-Base, (b) determine if differences exist in interval velocities and acceleration between left- and right-handed batters or between-position groupings, and (c) to quantify determinants of time to First-Base in Major-League Baseball players during actual games. A total of 1,896 sprint times to the Foul-Line (13.7 m) and First-Base (27.4 m) were recorded in 302 baseball players by a single coach, positioned in the dugout with a hand-held stopwatch. Interval velocities and accelerations were computed between Home-Plate and the Foul-Line and the Foul-Line and First-Base; average velocity and acceleration were also determined over the entire 27.4 m. Velocity and acceleration for left-handed batters were greater than for right-handed batters from Home-Plate to the Foul-Line and from Home-Plate to First-Base; however, there were no differences in velocity or acceleration from the Foul-Line to First-Base. Interval velocity was significantly greater for outfielders and infielders compared with that for catchers from Home-Plate to the Foul-Line and from the Home-Plate to First-Base. Outfielders were faster than catchers from the Foul-Line to First-Base; no other between-group differences were evident. Accelerations from Home-Plate to the Foul-Line and from Home-Plate to First-Base were greater for outfielders compared with infielders and catchers. Infielders accelerated at greater rates than did catchers between these intervals. There were no between-position differences in acceleration from the Foul-Line to First-Base. These data indicate that time to First-Base is most affected by acceleration from Home-Plate to the Foul-Line. Coaches should implement strategies that encourage players to sprint maximally over the first 13.7 m to maximize chances of successfully reaching First-Base.     

Activity profile of young soccer players during actual match play

This study investigated the activity profile of young soccer players (mean age 11.8 +/- 0.6 years; N = 12) with the aim of providing information for the development of training strategies. Data for movements of each player were obtained using 2 cameras that aimed at the subject throughout the match (Play Controller, Phromos, Italy). Encoders transmitted camera movements to a computer. The collected signals were then converted into distances, times, and speed attained at arbitrarily selected match categories. Players were monitored during official 11 vs. 11 matches (N = 12), with each match consisting of 2 halves, each lasting 30 minutes played on a regular soccer pitch. Mean total match distance amounted to 6,175 +/- 318 m. During the second half, players covered 5.5% less distance (p > 0.05). At speeds between 13.1 and 18.0 km.h(-1), players covered 12% less distance during the second half (p < 0.05). Players stood still 11% of the total time played (3,789 +/- 109 seconds). At speeds faster than 18 km.h(-1), players performed 33 +/- 4 bouts during match play, with a mean time length of 2.3 +/- 0.6 seconds per bout. Mean time interval between two successive maximal sprint bouts was 118.5 +/- 20.5 seconds. Players stood still longer during the course of the second half (229 +/- 76 seconds vs. 173 +/- 61 seconds, p < 0.05). Players tended to play in small areas of the football pitch and spent 9% of the total match time at high intensity. In order to promote a more active space coverage of the young player, at least for the age considered in the present study, the dimensions of the football pitch and the number of players should be reduced.     

Effects of electromyostimulation training on muscle strength and power of elite rugby players

The present study investigated the influence of a 12-week electromyostimulation (EMS) training program performed by elite rugby players. Twenty-five rugby players participated in the study, 15 in an electrostimulated group and the remaining 10 in a control group. EMS was conducted on the knee extensor, plantar flexor, and gluteus muscles. During the first 6 weeks, training sessions were carried out 3 times a week and during the last 6 weeks, once a week. Isokinetic torque of the knee extensors was determined at different eccentric and concentric angular velocities ranging from -120 to 360 degrees .s(-1). Scrummaging and full squat strength, vertical jump height and sprint-running times were also evaluated. After the first 6 weeks of EMS, only the squat strength was significantly improved (+8.3 +/- 6.5%; p < 0.01). After the 12th week, the -120 degrees .s(-1) maximal eccentric, 120 and 240 degrees .s(-1) maximal concentric torque (p < 0.05), squat strength (+15.0 +/- 8.0%; p < 0.001), squat jump (+10.0 +/- 9.5%; p < 0.01), and drop jump from a 40-cm height (+6.6 +/- 6.1%; p < 0.05) were significantly improved. No significant change was observed for the control group. A 12-week EMS training program demonstrated beneficial effects on muscle strength and power in elite rugby players on particular tests. However, rugby skills such as scrummaging and sprinting were not enhanced.     

The relationship between selected blood lactate thresholds and match performance in elite soccer referees

The aim of this study was to examine the relationship between selected blood lactate thresholds and competitive match activities in elite soccer referees. Eight elite-level referees (mean age, 37.6 +/- 3.4 years) were each observed during 2 Serie A matches (n = 16), and the mean of each match activity was used for analysis. Match activities were monitored using a technology similar to that reported by Ohashi and others. Blood lactate thresholds were assessed under field conditions during a progressive multistage protocol. Running velocities attained at selected blood lactate concentrations (2 and 4 mmol x L(-1), V2 and V4, respectively) were chosen because these are commonly used to assess endurance performance. Analyses of correlations were performed considering V2 and V4 values as independent variables and total distance, maximal velocity distance (runs performed at velocities faster than 24 km x h(-1)) and high-intensity activity distance (runs performed at velocities faster than 18 km x h(-1)) as dependent variables. Significance was set at p 相似文献   

Training leading to repetition failure enhances bench press strength gains in elite junior athletes

The purpose of this study was to investigate the importance of training leading to repetition failure in the performance of 2 different tests: 6 repetition maximum (6RM) bench press strength and 40-kg bench throw power in elite junior athletes. Subjects were 26 elite junior male basketball players (n = 12; age = 18.6 +/- 0.3 years; height = 202.0 +/- 11.6 cm; mass = 97.0 +/- 12.9 kg; mean +/- SD) and soccer players (n = 14; age = 17.4 +/- 0.5 years; height = 179.0 +/- 7.0 cm; mass = 75.0 +/- 7.1 kg) with a history of greater than 6 months' strength training. Subjects were initially tested twice for 6RM bench press mass and 40-kg Smith machine bench throw power output (in watts) to establish retest reliability. Subjects then undertook bench press training with 3 sessions per week for 6 weeks, using equal volume programs (24 repetitions x 80-105% 6RM in 13 minutes 20 seconds). Subjects were assigned to one of two experimental groups designed either to elicit repetition failure with 4 sets of 6 repetitions every 260 seconds (RF(4 x 6)) or allow all repetitions to be completed with 8 sets of 3 repetitions every 113 seconds (NF(8 x 3)). The RF(4 x 6) treatment elicited substantial increases in strength (7.3 +/- 2.4 kg, +9.5%, p < 0.001) and power (40.8 +/- 24.1 W, +10.6%, p < 0.001), while the NF(8 x 3) group elicited 3.6 +/- 3.0 kg (+5.0%, p < 0.005) and 25 +/- 19.0 W increases (+6.8%, p < 0.001). The improvements in the RF(4 x 6) group were greater than those in the repetition rest group for both strength (p < 0.005) and power (p < 0.05). Bench press training that leads to repetition failure induces greater strength gains than nonfailure training in the bench press exercise for elite junior team sport athletes.     

Match activities of elite women soccer players at different performance levels

We sought to study the physical demands and match performance of women soccer players. Nineteen top-class and 15 high-level players were individually videotaped in competitive matches, and time-motion analysis were performed. The players changed locomotor activity >1,300 times in a game corresponding to every ~4 seconds and covered 9-11 km in total. The top-class players ran 28% longer (P < 0.05) at high intensities than high-level players (1.68 +/- 0.09 and 1.33 +/- 0.10 km, respectively) and sprinted 24% longer (P < 0.05). The top-class group had a decrease (P < 0.05) of 25-57% in high intensity running in the final 15 minutes compared with the first four 15-minutes intervals, whereas the high-level group performed less (P < 0.05) high-intensity running in the last 15 minutes of each half in comparison with the 2 previous 15-minute periods in the respective half. Peak distance covered by high intensity running in a 5-minute interval was 33% longer (P < 0.05) for the top-class players than the high-level players. In the following 5 minutes immediately after the peak interval top-class players covered 17% less (P < 0.05) high-intensity running than the game average. Defenders performed fewer (P < 0.05) intervals of high-intensity running than midfielders and attackers, as well as fewer (P < 0.05) sprints than the attackers. In conclusion, for women soccer players (1) top-class international players perform more intervals of high-intensity running than elite players at a lower level, (2) fatigue develops temporarily during and towards the end of a game, and (3) defenders have lower work rates than midfielders and attackers. The difference in high-intensity running between the 2 levels demonstrates the importance of intense intermittent exercise for match performance in women soccer. Thus, these aspects should be trained intensively in women soccer.     

The influence of a congested calendar on physical performance in elite soccer

The aim of this study was to investigate recovery via analysis of activity profiles in a professional soccer team over an intense period of matches. A total of 172 outfield players from 27 Spanish League matches played by a professional team during the 2005-2006 season were analyzed using a multiple-camera match analysis system. The dependent variables were the distance covered by players at different intensities. Data were analyzed using an independent-sample t-test and a linear regression analysis with 5 independent variables: the number of matches played per week (1 or 2), match status (i.e., whether the team was winning, losing or drawing), match location (i.e., playing at home or away), quality of the opponents (strong or weak), and the individual playing position of the players. The main finding of this study suggests that the activity profiles of professional soccer players were not influenced by short recovery between matches. Although those players who played 2 matches a week covered less distance at maximal (>23 km·h(-1)), submaximal (19.1-23 km·h(-1)), and medium (14.1-19 km·h(-1)) intensities than those players who played 1 match a week, no significant differences were found. Moreover, results from this study seem to confirm that the elite soccer players' distance covered at various speeds is dependent on match contextual factors. The top-class players performed less high-intensity activity (>19.1 km·h(-1)) when winning than when they were losing (p < 0.05), but more distance was covered by walking and jogging when winning (p < 0.05). The home teams covered a greater distance than away teams at low intensity (<14.1 km·h(-1)) (p < 0.01). Finally, the better the quality of the opponent, the higher the distance covered by walking and jogging.     

A comparison of the magnitude and duration of linear and rotational head accelerations generated during hand-, elbow- and shoulder-to-head checks delivered by hockey players

Ice hockey has the highest rates for concussion among team sports in Canada. In elite play, the most common mechanism is impact to the head by an opposing player’s upper limb, with shoulder-to-head impacts accounting for twice as many concussions as elbow- and hand-to-head impacts combined. Improved understanding of the biomechanics of head impacts in hockey may inform approaches to prevention. In this study, we measured the magnitude and duration of linear and rotational head accelerations when hockey players (n = 11; aged 21–25) delivered checks “as hard as comfortable” to the head of an instrumented dummy with their shoulder, elbow and hand. There were differences in both peak magnitude and duration of head accelerations across upper limb impact sites, based on repeated-measures ANOVA (p < 0.005). Peak linear head accelerations averaged 1.9-fold greater for hand and 1.3-fold greater for elbow than shoulder (mean values = 20.35, 14.23 and 10.55 g, respectively). Furthermore, peak rotational head accelerations averaged 2.1-fold greater for hand and 1.8-fold greater for elbow than shoulder (1097.9, 944.1 and 523.1 rad/s², respectively). However, times to peak linear head acceleration (a measure of the duration of the acceleration impulse) were 2.1-fold longer for shoulder than elbow, and 2.5-fold longer for shoulder than hand (12.26, 5.94 and 4.98 ms, respectively), and there were similar trends in the durations of rotational head acceleration. Our results show that, in body checks to the head delivered by varsity-level hockey players, shoulder-to-head impacts generated longer durations but lower magnitude of peak head acceleration than elbow- and hand-to-head impacts.     

Body composition and physical fitness of female volleyball and basketball players of the Japan inter-high school championship teams

This study evaluated the body composition (underwater weighing) and cardiorespiratory function (VO(2)max and O(2)debt max measured by the treadmill exercise test) in 12 members of the women's volleyball team (mean age 17.4 years) and 11 members of the women's basketball team (mean age 17.6 years) that won the championship in the Japan Inter-high School Meeting. We also examined differences in the physical abilities between the members of the top teams of different events. The following results were obtained. (1) The mean values of the height and body weight were 168.7+/-5.89 cm and 59.7+/-5.73 kg in the volleyball players and 166.5+/-7.87 cm and 58.8+/-6.85 kg in the basketball players. (2) The mean %Fat was 18.4+/-3.29% in the volleyball players and 15.7+/-5.05% in the basketball players, and was similar to the reported values in elite adult players. (3) The mean VO(2)max was 2.78+/-0.32 L x min(-1) (46.5+/-2.90 ml x kg(-1) x min(-1)) in the volleyball players and 3.32+/-0.31 L x min(-1) (56.7+/-4.17 ml x kg(-1) x min(-1)) in the basketball players, and was similar to the reported values in elite adult players. (4) The mean O(2)debt max was 6.18+/-1.15 L (103.2+/-12.40 ml x kg(-1)) in the volleyball players and 7.92+/-1.80 L (134.3+/-23.24 ml x kg(-1)) in the basketball players. These values were 2.6 times and 3.3 times as high as the average values in high school students in general. (5) No significant difference was observed in any measured item of the physique, skinfold thickness, or body composition between the volleyball players and basketball players. (6) The VO(2)max and O(2)debt max were 22% and 28% higher in the basketball players than in the volleyball players.From these results, the female volleyball players and basketball players evaluated in this study had the physical abilities needed to win the championship in the Japan Inter-high School Meets, i.e. a large FFM and excellent aerobic and anaerobic work capacities. Also, basketball appears to require higher aerobic and anaerobic work capacities than volleyball.     

Time-motion analysis of small-sided training games and competition in elite women soccer players

We investigated the movement patterns of small-sided training games and compared these movement patterns with domestic, national, and international standard competition in elite women soccer players. In addition, we investigated the repeated-sprint demands of women's soccer with respect to the duration of sprints, number of sprint repetitions, recovery duration, and recovery intensity. Thirteen elite women soccer players [age (mean +/- SD) 21 +/- 2 years] participated in this study. Time-motion analysis was completed during training (n = 39) consisting of small-sided (i.e., three versus three and five versus five) training games, domestic matches against male youth teams (n = 10), Australian national-league matches (n = 9), and international matches (n = 12). A repeated-sprint bout was defined as a minimum of three sprints, with recovery of less than 21 seconds between sprints. The overall exercise to rest ratios for small-sided training games (1:13) were similar to or greater than domestic competition against male youth teams (1:15) and national-league (1:16) and international (1:12) competitions. During the international matches analyzed, 4.8 +/- 2.8 repeated-sprint bouts occurred per player, per match. The number of sprints within the repeated-sprint bouts was 3.4 +/- 0.8. The sprint duration was 2.1 +/- 0.7 seconds, and the recovery time between sprints was 5.8 +/- 4.0 seconds. Most recovery between sprints was active in nature (92.6%). In contrast to international competition, repeated-sprint bouts were uncommon in small-sided training games, domestic competition against male youth teams, and national-league competition. These findings demonstrate that small-sided training games simulate the overall movement patterns of women's soccer competition but offer an insufficient training stimulus to simulate the high-intensity, repeated-sprint demands of international competition.     

Monitoring external load in elite male handball players depending on playing positions

Monitoring workload is critical for elite training and competition, as well as preventing potential sports injuries. The assessment of external load in team sports has been provided with new technologies that help coaches to individualize training and optimize their team’s playing system. In this study we characterized the physical demands of an elite handball team during an entire sports season. Novel data are reported for each playing position of this highly strenuous body-contact team sport. Sixteen world top players (5 wings, 2 centre backs, 6 backs, 3 line players) were equipped with a local positioning system (WIMU PRO) during fourteen official Spanish first league matches. Playing time, total distance covered at different running speeds, and acceleration variables were monitored. During a handball match, wings cover the greater distance by high-speed running (> 5.0 m·s^-1): 410.3 ± 193.2 m, and by sprint (> 6.7 m·s^-1): 98.0 ± 75.4 m. Centre backs perform the following playing position that supports the highest speed intensities during the matches: high-speed running: 243.2 ± 130.2 m; sprint: 62.0 ± 54.2 m. Centre backs also register the largest number of high-intensity decelerations (n = 142.7 ± 59.5) compared to wings (n = 112.9 ± 56.0), backs (n = 105.2 ± 49.2) and line players: 99.6 ± 28.9). This study provides helpful information for professional coaches and their technical staff to optimize training load and individualize the physical demands of their elite male handball players depending on each playing position.     

Heart rate responses during small-sided games and short intermittent running training in elite soccer players: a comparative study

The purpose of this study was to compare heart rate (HR) responses within and between physical controlled (short-duration intermittent running) and physical integrated (sided games) training methods in elite soccer players. Ten adult male elite soccer players (age, 26 +/- 2.9 years; body mass, 78.3 +/- 4.4 kg; maximum HR [HRmax], 195.4 +/- 4.9 b x min(-1) and velocity at maximal aerobic speed (MAS), 17.1 +/- 0.8 km x h(-1)) performed different short-duration intermittent runs, e.g., 30-30 (30 seconds of exercise interspersed with 30 seconds of recovery) with active recovery, and 30-30, 15-15, 10-10, and 5-20 seconds with passive recovery, and different sided games (1 versus 1, 2 versus 2, 4 versus 4, 8 versus 8 with and without a goalkeeper, and 10 versus 10). In both training methods, HR was measured and expressed as a mean percentage of HR reserve (%HRres). The %HRres in the 30-30-second intermittent run at 100% MAS with active recovery (at 9 km.h with corresponding distance) was significantly higher than that with passive recovery (85.7% versus 77.2% HRres, respectively, p < 0.001) but also higher than the 1 versus 1 (p < 0.01), 4 versus 4 (p 相似文献   

Accelerated Return to Play in Professional Basketball Players With Surgically-Treated Metacarpal Shaft Fractures

BackgroundTraditional rehabilitation protocols for surgically treated metacarpal shaft fracture allow for return to play at 6-8 weeks post-operative. This may be devastating for the elite athlete. We outline a protocol that may allow for professional basketball players to successfully return to sport within four weeks following surgery.MethodsProfessional basketball players who sustained non-thumb metacarpal shaft fractures were included. All athletes underwent open reduction and internal fixation of the injured metacarpal. Patients were subsequently enrolled into an accelerated rehabilitation protocol.ResultsThe five athletes in our case series successfully passed return to sport testing within four weeks of surgery.ConclusionA plate and screw construct can potentially allow for professional basketball players to return to play in half the time. Future research studies should include a larger pool of athletes to further investigate accelerated rehabilitation following surgical fixation of metacarpal fractures. Level of Evidence: IV