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1.
Abstract

The aims of this study were to establish the physical and physiological attributes of elite and sub-elite Malaysian male badminton players and to determine whether these attributes discriminate elite players from sub-elite players. Measurements and tests of basic anthropometry, explosive power, anaerobic recovery capacity, badminton-specific movement agility, maximum strength, and aerobic capacity were conducted on two occasions, separated by at least one day. The elite (n = 12) and sub-elite (n = 12) players' characteristics were, respectively: mean age 24.6 years (s = 3.7) and 20.5 years (s = 0.7); mass 73.2 kg (s = 7.6) and 62.7 kg (s = 4.2); stature 1.76 m (s = 0.07) and 1.71 m (s = 0.05); body fat 12.5% (s = 4.8) and 9.5% (s = 3.4); estimated VO2max 56.9 ml · kg?1 · min?1 (s = 3.7) and 59.5 ml · kg?1 · min?1 (s = 5.2). The elite players had greater maximum absolute strength in one-repetition maximum bench press (P = 0.015) compared with the sub-elite players. There were significant differences in instantaneous lower body power estimated from vertical jump height between the elite and sub-elite groups (P < 0.01). However, there was no significant difference between groups in shuttle run tests and on-court badminton-specific movement agility tests. Our results show that elite Malaysian male badminton players are taller, heavier, and stronger than their sub-elite counterparts. The test battery, however, did not allow us to discriminate between the elite and sub-elite players, suggesting that at the elite level tactical knowledge, technical skills, and psychological readiness could be of greater importance.  相似文献   

2.
Abstract

The single-stage treadmill walking test of Ebbeling et al. is commonly used to predict maximal oxygen consumption ([Vdot]O2max) from a submaximal effort between 50% and 70% of the participant's age-predicted maximum heart rate. The purpose of this study was to determine if this submaximal test correctly predicts [Vdot]O2max at the low (50% of maximum heart rate) and high (70% of maximum heart rate) ends of the specified heart rate range for males and females aged 18 – 55 years. Each of the 34 participants completed one low-intensity and one high-intensity trial. The two trials resulted in significantly different estimates of [Vdot]O2max (low-intensity trial: mean 40.5 ml · kg?1 · min?1, s = 9.3; high-intensity trial: 47.5 ml · kg?1 · min?1, s = 8.8; P < 0.01). A subset of 22 participants concluded their second trial with a [Vdot]O2max test (mean 47.9 ml · kg?1 · min?1, s = 8.9). The low-intensity trial underestimated (mean difference = ?3.5 ml · kg?1 · min?1; 95% CI = ?6.4 to ?0.6 ml · kg?1 · min?1; P = 0.02) and the high-intensity trial overestimated (mean difference = 3.5 ml · kg?1 · min?1; 95% CI = 1.1 to 6.0 ml · kg?1 · min?1; P = 0.01) the measured [Vdot]O2max. The predictive validity of Ebbeling and colleagues' single-stage submaximal treadmill walking test is diminished when performed at the extremes of the specified heart rate range.  相似文献   

3.
Abstract

We assessed the agreement between maximal oxygen consumption ([Vdot]O2max) measured directly when performing the 20-m shuttle run test and estimated [Vdot]O2max from five different equations (i.e. Barnett, equations a and b; Léger; Matsuzaka; and Ruiz) in youths. The 20-m shuttle run test was performed by 26 girls (mean age 14.6 years, s = 1.5; body mass 57.2 kg, s = 8.9; height 1.60 m, s = 0.06) and 22 boys (age 15.0 years, s = 1.6; body mass 63.5 kg, s = 11.5; height 1.70 m, s = 0.01). The participants wore a portable gas analyser (K4b2, Cosmed) to measure [Vdot]O2 during the test. All the equations significantly underestimated directly measured [Vdot]O2max, except Barnett's (b) equation. The mean difference ranged from 1.3 ml · kg?1 · min?1 (Barnett (b)) to 5.5 ml · kg?1 · min?1 (Léger). The standard error of the estimate ranged from 5.3 ml · kg?1 · min?1 (Ruiz) to 6.5 ml · kg?1 · min?1 (Léger), and the percentage error ranged from 21.2% (Ruiz) to 38.3% (Léger). The accuracy of the equations available to estimate [Vdot]O2max from the 20-m shuttle run test is questionable at the individual level. Furthermore, special attention should be paid when comparisons are made between studies (e.g. population-based studies) using different equations. The results of the present study suggest that Barnett's (b) equation provides the closest agreement with directly measured [Vdot]O2max (cardiorespiratory fitness) in youth.  相似文献   

4.
Pacing strategies of elite swimmers have been consistently characterised from the average lap velocities. In the present study, we examined the racing strategies of 200 m world class-level swimmers with regard to their underwater and surface lap components. The finals and semi-finals of the 200 m races at the 2013 World Swimming Championships (Barcelona, Spain) were analysed by an innovative image-processing system (InThePool® 2.0). Free swimming velocities of elite swimmers typically decreased throughout the 200 m race laps (?0.12 m · s–1, 95% CI ?0.11 to ?0.14 m · s–1, P = 0.001, η2 = 0.81), whereas underwater velocities, which were faster than free swimming, were not meaningfully affected by the race progress (0.02 m · s–1, ?0.01 to 0.04 m · s–1, P = 0.01, η2 = 0.04). When swimming underwater, elite swimmers typically travelled less distance (?0.66 m, ?0.83 to ?0.49 m, P = 0.001, η2 = 0.34) from the first to the third turn of the race, although underwater distances were maintained on the backstroke and butterfly races. These strategies allowed swimmers to maintain their average velocity in the last lap despite a decrease in the free swimming velocity. Elite coaches and swimmers are advised to model their racing strategies by considering both underwater and surface race components.  相似文献   

5.
Abstract

The aim of this study was to compare the physiological and psychological responses of cyclists riding on a hard tail bicycle and on a full suspension bicycle. Twenty males participated in two series of tests. A test rig held the front axle of the bicycle steady while the rear wheel rotated against a heavy roller with bumps (or no bumps) on its surface. In the first series of tests, eight participants (age 19 – 27 years, body mass 65 – 82 kg) were tested on both the full suspension and hard tail bicycles with and without bumps fitted to the roller. The second series of test repeated the bump tests with a further six participants (age 22 – 31 years, body mass 74 – 94 kg) and also involved an investigation of familiarization effects with the final six participants (age 21 – 30 years, body mass 64 – 80 kg). Heart rate, oxygen consumption ([Vdot]O2), rating of perceived exertion (RPE) and comfort were recorded during 10 min sub-maximal tests. Combined data for the bumps tests show that the full suspension bicycle was significantly different (P < 0.001) from the hard tail bicycle on all four measures. Oxygen consumption, heart rate and RPE were lower on average by 8.7 (s = 3.6) ml · kg?1 · min?1, 32.1 (s = 12.1) beats · min?1 and 2.6 (s = 2.0) units, respectively. Comfort scores were higher (better) on average by 1.9 (s = 0.8) units. For the no bumps tests, the only statistically significant difference (P = 0.008) was in [Vdot]O2, which was lower for the hard tail bicycle by 2.2 (s = 1.7) ml · kg?1 · min?1. The results indicate that the full suspension bicycle provides a physiological and psychological advantage over the hard tail bicycle during simulated sub-maximal exercise on bumps.  相似文献   

6.
Abstract

Twenty-four players from the 1st/2nd (elite) and 24 players from the 3rd/4th (non-elite) university football teams were recruited to evaluate the Loughborough Soccer Passing Test (LSPT) and Loughborough Soccer Shooting Test (LSST) as tools to assess soccer skill. The LSPT requires players to complete 16 passes as quickly as possible. The LSST requires players to pass, control, and shoot the ball to targets on a full-sized goal. Participants completed two main trials each separated by at least one day. During both trials, the participants were given practice efforts before recording the mean of the next two (LSPT) or 10 (LSST) attempts as the performance score. For the LSPT, the mean time taken, added penalty time, and overall performance time were less in the elite players (elite: 43.6 s, s = 3.8; non-elite: 52.5 s, s = 7.4; P = 0.0001). For the LSST, there was no difference in the mean points scored per shot between groups (elite: 1.34, s = 0.46; non-elite: 1.28, s = 0.53). However, the elite players had higher mean shot speed (elite: 80 km · h?1, s = 4.5; non-elite: 74 km · h?1, s = 4.2; P < 0.0001) and performed each shot sequence faster (elite: 7.87 s, s = 0.29; non-elite: 8.07 s, s = 0.35; P = 0.037) than the non-elite players. Performance on both tests was more repeatable in elite players. In conclusion, the LSPT and LSST are valid and reliable protocols to assess differences in soccer skill performance.  相似文献   

7.
Abstract

This study investigated the influence of dehydration during soccer-type intermittent exercise on isokinetic and isometric muscle function. Eight soccer players performed two 90-min high-intensity intermittent shuttle-running trials without (NF) or with (FL) fluid ingestion (5 ml · kg?1 before and 2 ml · kg?1 every 15 min). Isokinetic and isometric strength and muscular power of knee flexors and knee extensors were measured pre-exercise, at half-time and post-exercise using isokinetic dynamometry. Sprint performance was monitored throughout the simulated-soccer exercise. Isokinetic knee strength was reduced at faster (3.13 rad · s?1; P = 0.009) but not slower (1.05 rad · s?1; P = 0.063) contraction speeds with exercise; however, there was no difference between FL and NF. Peak isometric strength of the knee extensors (P = 0.002) but not the knee flexors (P = 0.065) was significantly reduced with exercise with no difference between FL and NF. Average muscular power was reduced over time at both 1.05 rad · s?1 (P = 0.01) and 3.14 rad · s?1 (P = 0.033) but was not different between FL and NF. Mean 15-m sprint time increased with duration of exercise (P = 0.005) but was not different between FL and NF. In summary, fluid ingestion during 90 min of soccer-type exercise was unable to offset the reduction in isokinetic and isometric strength and muscular power of the knee extensors and flexors.  相似文献   

8.
Abstract

In this study, we examine the effect of exercise on the time and flow characteristics of the respiratory cycle profile at the point of volitional exercise termination. Eight males (mean age 29 years, s = 10; body mass 74 kg, s = 7; height 1.75 m, s = 0.04) undertook a cycle test to volitional exhaustion on a cycle ergometer, which allowed peak oxygen uptake ([Vdot]O2peak) to be measured (mean 51 ml · kg?1 · min?1, s = 7). At a later date, two sub-maximal tests to volitional exhaustion were completed in a random order at 76% (s = 6) and 86%[Vdot]O2peak (s = 7). As expected, the magnitude of the respiratory flow and time characteristics varied with the three exercise intensities, as did the point of exercise termination and terminal ventilation rates, which varied from 7 to 27 min and 112 to 132 litres · min?1 respectively. More importantly, however, at exercise termination some of the characteristics were similar, particularly the breathing frequency (at termination 49 breaths · min?1), the ratio between inspiration and total breath time (0.5), and the later occurrence of peak inspiratory flow (0.24 – 0.48 s). The coincident unity of these time and flow profile characteristics at exercise termination illustrates how the integration of timing and flow during breathing influence exercise capacity in non-elite athletes.  相似文献   

9.
Abstract

Spinning is a type of indoor fitness activity performed on stationary bikes by participants who pedal together to the rhythm of music and the motivating words of an instructor. Despite worldwide popularity of this type of recreational activity, to date there have been few, mainly non-scientific, studies of the impact of spinning on metabolic, respiratory, and cardiovascular functions. The main aim of this study was to evaluate a number of metabolic and cardiovascular variables during a standard 50-min class performed by Spinning® instructors of both sexes: six males (age 30 ± 4.8 years, body mass index 24 ± 2.5 kg · m?2; mean ± s) and six females (age 34 ± 6.3 years, body mass index 21 ± 1.9 kg · m?2). The mean power output, heart rate, and oxygen uptake during the performance were 120 ± 4 W, 136 ± 13 beats · min?1, and 32.8 ± 5.4 ml · kg?1 · min?1 respectively for males, and 73 ± 43 W, 143 ± 25 beats · min?1, and 30 ± 9.9 ml · kg?1 · min?1 respectively for females. Analysis of individual performances showed that they were compatible with physical exercise that ranged from moderate-to-heavy to very heavy, the latter conditions prevailing. The results show that this type of fitness activity has a high impact on cardiovascular function and suggest that it is not suitable for unfit or sedentary individuals, especially the middle aged or elderly, who are willing to begin a recreational physical activity programme.  相似文献   

10.
Abstract

The purpose of the present study was to measure and compare peak oxygen uptake and paddling efficiency in recreational and competitive junior male surfers. Eight male recreational surfers (mean age 18 years, s=2; mass 66.8 kg, s=13.0; height 1.75 m, s=0.10) and eight male competitive surfers (mean age 18 years, s=1; mass 68.0 kg, s=11.7; height 1.72 m, s=0.10) performed an incremental paddling test consisting of four 3-min constant load work stages followed by a ramp increase in power output of 20 W · 30 s?1 until exhaustion. The oxygen uptake–power output relationship of the four constant load work stages and peak values obtained during the incremental paddling test were used to calculate paddling efficiency. No differences (P>0.05) were observed between the recreational and competitive surfers for peak oxygen uptake (recreational: 2.52 litres · min?1, s=0.5; competitive: 2.66 litres · min?1, s=0.35) or efficiency (recreational: 24%, s=3; competitive: 21%, s=4). Blood lactate concentration was significantly greater in recreational (2.4 mmol · l?1, s=0.9) than competitive surfers (1.6 mmol · l?1, s=0.5) during submaximal paddling. There were no differences in peak oxygen uptake or paddling efficiency between recreational and competitive surfers suggesting that peak oxygen uptake and efficiency are not sensitive to differences in surfing ability. The increase in blood lactate concentration during submaximal paddling in recreational compared with competitive surfers suggests that other determinants of paddling endurance, such as blood lactate threshold, might be better at distinguishing surfers of differing ability.  相似文献   

11.
Abstract

We compared starters and non-starters for various isokinetic strength variables in elite women’s soccer players. A convenience sample of 10 starters (mean ± s; age = 20 ± 2 years; height = 170 ± 4 cm; body mass = 65 ± 5 kg) and 7 non-starters (age = 20 ± 1 years; height = 164 ± 3 cm; body mass = 63 ± 4 kg) performed maximal voluntary muscle actions of the leg extensors (concentric) and flexors (eccentric) on an isokinetic dynamometer in order to measure concentric peak torque for the leg extensors, eccentric peak torque for the leg flexors, and the functional hamstrings:quadriceps (H:Q) ratio at 1.047 rad · s-1 and 4.189 rad · s-1 concentric peak torque for the leg extensors was not different between starters and non-starters. However, it was greater at 1.047 rad · s-1 than at 4.189 rad · s-1 in both groups. Eccentric peak torque for the leg flexors was greater for the starters versus non-starters at 4.189 rad · s-1. Eccentric strength of the leg flexors at fast movement velocities may be used as an effective physiological profile and may discriminate between playing status in elite women’s soccer players.  相似文献   

12.
Abstract

Elite badminton requires muscular endurance combined with appropriate maximal and explosive muscle strength. The musculature of the lower extremities is especially important in this context since rapid and forceful movements with the weight of the body are performed repeatedly throughout a match. In the present study, we examined various leg-strength parameters of 35 male elite badminton players who had been performing resistance exercises as part of their physical training for several years. The badminton players were compared with an age-matched reference group, the members of whom were physically active on a recreational basis, and to the same reference group after they had performed resistance training for 14 weeks. Maximal muscle strength of the knee extensor (quadriceps) and flexor muscles (hamstrings) was determined using isokinetic dynamometry. To measure explosive muscle strength, the contractile rate of force development was determined during maximal isometric muscle contractions. In general, the badminton players showed greater maximal muscle strength and contractile rate of force development than the reference group: mean quadriceps peak torque during slow concentric contraction: 3.69 Nm · kg?1, s=0.08 vs. 3.26 Nm · kg?1, s=0.8 (P<0.001); mean hamstring peak torque during slow concentric contraction: 1.86 Nm · kg?1, s=0.04 vs. 1.63 Nm · kg?1, s=0.04 (P<0.001); mean quadriceps rate of force development at 100 ms: 24.4 Nm · s?1·kg?1, s=0.5 vs. 22.1 Nm·s?1 · kg?1, s=0.6 (P<0.05); mean hamstring rate of force development at 100 ms: 11.4 Nm · s?1·kg?1, s=0.3 vs. 8.9 Nm · s?1 · kg?1, s=0.4 (P<0.05). However, after 14 weeks of resistance training the reference group achieved similar isometric and slow concentric muscle strength as the badminton players, although the badminton players still had a higher isometric rate of force development and muscle strength during fast (240° · s?1) quadriceps contractions. Large volumes of concurrent endurance training could have attenuated the long-term development of maximal muscle strength in the badminton players. The badminton players had a higher contractile rate of force development than the reference group before and after resistance training. Greater explosive muscle strength in the badminton players might be a physiological adaptation to their badminton training.  相似文献   

13.
Abstract

The aim of this study was to determine if inducing metabolic alkalosis would alter neuromuscular control after 50 min of standardized submaximal cycling. Eight trained male cyclists (mean age 32 years, s = 7; [Vdot]O2max 62 ml · kg?1 · min?1, s = 8) ingested capsules containing either CaCO3 (placebo) or NaHCO3 (0.3 g · kg?1 body mass) in eight doses over 2 h on two separate occasions, commencing 3 h before exercise. Participants performed three maximal isometric voluntary contractions (MVC) of the knee extensors while determining the central activation ratio by superimposing electrical stimulation both pre-ingestion and post-exercise, followed by a 50-s sustained maximal contraction in which force, EMG amplitude, and muscle fibre conduction velocity were assessed. Plasma pH, blood base excess, and plasma HCO3 were higher (P < 0.01) during the NaHCO3 trial. After cycling, muscle fibre conduction velocity was higher (P < 0.05) during the 50-s sustained maximal contraction with NaHCO3 than with placebo (5.1 m · s?1, s = 0.4 vs. 4.2 m · s?1, s = 0.4) while the EMG amplitude remained the same. Force decline rate was less (P < 0.05) during alkalosis-sustained maximal contraction and no differences were shown in central activation ratio. These data indicate that induced metabolic alkalosis can increase muscle fibre conduction velocity following prolonged submaximal cycling.  相似文献   

14.
Assessment of movement logging devices is required to ensure suitability for the determination of court-movement variables during competitive sports performance and allow for practical recommendations to be made. Hence, the purpose was to examine wheelchair tennis speed profiles to assess data logger device applicability for court-movement quantification, with match play stratified by rank (HIGH, LOW), sex (male, female) and format (singles, doubles). Thirty-one wheelchair tennis players were monitored during competitive match play. Mixed sampling was employed (male = 23, female = 8). Friedman’s test with Wilcoxon signed-rank post hoc testing revealed a higher percentage of time below 2.5 m · s?1 [<2.5 vs. ≥2.5 m · s?1: 89.4 (5.0) vs. 1.2 (3.5)%, Z = ?4.860, P < 0.0005, r = 0.87] with the remaining time [9.0 (4.9%)] spent stationary. LOW-ranked players were stationary for longer than HIGH-ranked counterparts [12.6 (8.7) vs. 8.2 (5.1)%, U = 30.000, P = 0.011, r = 0.46] with more time at low propulsion speeds (<1.0 m · s?1). HIGH-ranked and doubles players spent more time in higher speed zones than respective counterparts. Females spent more time in the 1.0–1.49 m · s?1 zone (U = 48.000, P = 0.047, r = 0.36). Regardless of rank, sex or format, propulsion speeds during wheelchair tennis match play are consistent with data logger accuracy. Hence, data logging is appropriate for court-movement quantification.  相似文献   

15.
Abstract

Maximal oxygen uptake ([Vdot]O2max) is considered the optimal method to assess aerobic fitness. The measurement of [Vdot]O2max, however, requires special equipment and training. Maximal exercise testing with determination of maximal power output offers a more simple approach. This study explores the relationship between [Vdot]O2max and maximal power output in 247 children (139 boys and 108 girls) aged 7.9–11.1 years. Maximal oxygen uptake was measured by indirect calorimetry during a maximal ergometer exercise test with an initial workload of 30 W and 15 W · min?1 increments. Maximal power output was also measured. A sample (n = 124) was used to calculate reference equations, which were then validated using another sample (n = 123). The linear reference equation for both sexes combined was: [Vdot]O2max (ml · min?1) = 96 + 10.6 · maximal power + 3.5 · body mass. Using this reference equation, estimated [Vdot]O2max per unit of body mass (ml · min?1 · kg?1) calculated from maximal power correlated closely with the direct measurement of [Vdot]O2max (r = 0.91, P <0.001). Bland-Altman analysis gave a mean limits of agreement of 0.2±2.9 (ml · min?1 · kg?1) (1 s). Our results suggest that maximal power output serves as a good surrogate measurement for [Vdot]O2max in population studies of children aged 8–11 years.  相似文献   

16.
Abstract

In this study, video and force analysis techniques were used to distinguish between dragon boat paddlers of different ability. Six elite paddlers (three males, three females) and six sub-elite paddlers (two males, four females) were compared during high-intensity paddling (80–90 strokes · min?1). Video filming was conducted for two-dimensional kinematic analysis and an instrumented paddle was used to collect force data. Paddling efficiency, paddle force characteristics, and paddler kinematic variables were measured. Elite paddlers achieved higher paddling efficiency than sub-elite paddlers (elite: 76 ± 4%; sub-elite: 67 ± 10%; P = 0.080). Elite paddlers also showed higher peak force (elite: 16.3 ± 4.8 N · kg?2/3; sub-elite: 11.4 ± 2.6 N · kg?2/3; P = 0.052), average force (elite: 7.9 ± 2.8 N · kg?2/3; sub-elite: 5.5 ± 1.4 N · kg?2/3; P = 0.084), and impulse (elite: 3.0 ± 0.9 (N · s) · kg?2/3; sub-elite: 1.9 ± 0.4 (N · s) · kg?2/3; P = 0.026) than sub-elite paddlers, but these three results should be viewed with caution due to the small sample size and the unequal number of males and females in the two groups. Superior technique and greater strength enable the elite paddlers to achieve higher paddling efficiency. Paddlers use different joint movement patterns to develop propulsion, which are reflected in variations in the force–time curve.  相似文献   

17.
Abstract

The aims of this study were two-fold: (1) to consider the criterion-related validity of the multi-stage fitness test (MSFT) by comparing the predicted maximal oxygen uptake ([Vdot]O2max) and distance travelled with peak oxygen uptake ([Vdot]O2peak) measured using a wheelchair ergometer (n = 24); and (2) to assess the reliability of the MSFT in a sub-sample of wheelchair athletes (n = 10) measured on two occasions. Twenty-four trained male wheelchair basketball players (mean age 29 years, s = 6) took part in the study. All participants performed a continuous incremental wheelchair ergometer test to volitional exhaustion to determine [Vdot]O2peak, and the MSFT on an indoor wooden basketball court. Mean ergometer [Vdot]O2peak was 2.66 litres · min?1 (s = 0.49) and peak heart rate was 188 beats · min?1 (s = 10). The group mean MSFT distance travelled was 2056 m (s = 272) and mean peak heart rate was 186 beats · min?1 (s = 11). Low to moderate correlations (ρ = 0.39 to 0.58; 95% confidence interval [CI]: ?0.02 to 0.69 and 0.23 to 0.80) were found between distance travelled in the MSFT and different expressions of wheelchair ergometer [Vdot]O2peak. There was a mean bias of ?1.9 beats · min?1 (95% CI: ?5.9 to 2.0) and standard error of measurement of 6.6 beats · min?1 (95% CI: 5.4 to 8.8) between the ergometer and MSFT peak heart rates. A similar comparison of ergometer and predicted MSFT [Vdot]O2peak values revealed a large mean systematic bias of 15.3 ml · kg?1 · min?1 (95% CI: 13.2 to 17.4) and standard error of measurement of 3.5 ml · kg?1 · min?1 (95% CI: 2.8 to 4.6). Small standard errors of measurement for MSFT distance travelled (86 m; 95% CI: 59 to 157) and MSFT peak heart rate (2.4 beats · min?1; 95% CI: 1.7 to 4.5) suggest that these variables can be measured reliably. The results suggest that the multi-stage fitness test provides reliable data with this population, but does not fully reflect the aerobic capacity of wheelchair athletes directly.  相似文献   

18.
We analysed (i) the gender difference in cycling speed and (ii) the age of winning performers in the 508-mile “Furnace Creek 508”. Changes in cycling speeds and gender differences from 1983 to 2012 were analysed using linear, non-linear and hierarchical multi-level regression analyses for the annual three fastest women and men. Cycling speed increased non-linearly in men from 14.6 (s = 0.3) km · h?1 (1983) to 27.1 (s = 0.7) km · h?1 (2012) and non-linearly in women from 11.0 (s = 0.3) km · h?1 (1984) to 24.2 (s = 0.2) km · h?1 (2012). The gender difference in cycling speed decreased linearly from 26.2 (s = 0.5)% (1984) to 10.7 (s = 1.9)% (2012). The age of winning performers increased from 26 (s = 2) years (1984) to 43 (s = 11) years (2012) in women and from 33 (s = 6) years (1983) to 50 (s = 5) years (2012) in men. To summarise, these results suggest that (i) women will be able to narrow the gender gap in cycling speed in the near future in an ultra-endurance cycling race such as the “Furnace Creek 508” due to the linear decrease in gender difference and (ii) the maturity of these athletes has changed during the last three decades where winning performers become older and faster across years.  相似文献   

19.
Abstract

The aim of this study was to examine the effect of playing formation on high-intensity running and technical performance during elite soccer matches. Twenty English FA Premier League games were analysed using a multiple-camera computerized tracking system (n = 153 players). Overall ball possession did not differ (P > 0.05) between 4–4–2, 4–3–3 and 4–5–1 formations (50%, s = 7 vs. 49%, s = 8 vs. 44%, s = 6). No differences were observed in high-intensity running between 4–4–2, 4–3–3 and 4–5–1 formations. Compared with 4–4–2 and 4–3–3 formations, players in a 4–5–1 formation performed less very high-intensity running when their team was in possession (312 m, s = 196 vs. 433 m, s = 261 vs. 410 m, s = 270; P < 0.05) but more when their team was not in possession (547 m, s = 217 vs. 461 m, s = 156 vs. 459 m, s = 169; P < 0.05). Attackers in a 4–3–3 performed ～30% more (P < 0.05) high-intensity running than attackers in 4–4–2 and 4–5–1 formations. However, the fraction of successful passes was highest in a 4–4–2 (P < 0.05) compared with 4–3–3 and 4–5–1 formations. The results suggest that playing formation does not influence the overall activity profiles of players, except for attackers, but impacts on very high-intensity running activity with and without ball possession and some technical elements of performance.  相似文献   

20.
Abstract

Determination of the strongest possible relationship between isokinetic quadriceps and functional performance measurements in healthy females would allow sports medicine practitioners to establish normative values when examining muscular performance in injured females. Previous attempts to correlate both measurements have, however, produced inconsistent results. The purpose of this study was to examine the effects of allometric scaling, isokinetic testing velocities, reciprocal and non-reciprocal isokinetic testing on the relationship between countermovement jump (CMJ) and isokinetic quadriceps torque and power in recreational females athletes. Seventeen females (age 21.0 ± 2.0 years, body mass index 19.5 ± 1.0 kg · m?2) performed isokinetic quadriceps and CMJ tests. Isokinetic peak torque and average power were obtained reciprocally and non-reciprocally at 1.05 and 3.14 rad · s?1, and were corrected for body mass by allometric modelling. Pearson product–moment correlation (r) was used to assess the relationship between the isokinetic parameters and the CMJ measurements. Coefficients of determination (r 2) were calculated to determine the magnitude of common variance. The r-values for all non-allometrically modelled non-reciprocal parameters were greater (r = 0.58–0.63) than isokinetic parameters obtained reciprocally (r = 0.28–0.47). Using allometric scaling, non-reciprocal isokinetic data accounted for an additional 2–9% of the CMJ height variance, and statistically significant correlations were obtained at both 1.05 and 3.14 rad · s?1. Allometrically scaled, non-reciprocal isokinetic peak torque and average power at 1.05 rad · s?1 had the highest correlation with CMJ (r 2 = 0.49). At both 1.05 and 3.14 rad · s?1, non-reciprocal quadriceps parameters correlated more closely with CMJ measurements than do reciprocal contractions. Normalization for body size by allometrically scaling may further improve correlations with CMJ performance.  相似文献   

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