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1.
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2.
Running on side-sloped surfaces is a common obstacle in the environment; however, how and to what extent the lower extremity kinematics adapt is not well known. The purpose of this study was to determine the effects of side-sloped surfaces on three-dimensional kinematics of hip, knee, and ankle during stance phase of running. Ten healthy adult males ran barefoot along an inclinable runway in level (0°) and side-sloped (10° up-slope and down-slope inclinations, respectively) configurations. Right hip, knee, and ankle angles along with their time of occurrence were analysed using repeated measures MANOVA. Up-slope hip was more adducted (p = 0.015) and internally rotated (p = 0.030). Knee had greater external rotations during side-sloped running at heel-strike (p = 0.005), while at toe-off, it rotated externally and internally during up-slope and down-slope running, respectively (p = 0.001). Down-slope ankle had greatest plantar flexion (p = 0.001). Up-slope ankle had greatest eversion compared with down-slope (p = 0.043), while it was more externally rotated (p = 0.030). These motion patterns are necessary to adjust the lower extremity length during side-sloped running. Timing differences in the kinematic events of hip adduction and external rotation, and ankle eversion were observed (p = 0.006). Knowledge on these alterations is a valuable tool in adopting strategies to enhance performance while preventing injury.  相似文献   

3.
Abstract

The purpose was to evaluate the traditional method, of visually focusing on the ball, in comparison to focusing on the hole, during the putting stroke. The study design consisted of a pretest, a 4-week practice period, and a posttest. Participants (n = 31, handicap: 18.7 ± 10.4) practised using only one of the two gaze techniques. Testing consisted of having all participants putt using both gaze techniques from both a 1.22 m and a 4 m distance. Five putts were executed for each gaze technique/putt length combination for a total of 20 putts in each testing session per participant. The kinematics of every putting stroke executed during testing (1240 strokes) were captured using a TOMI® system. There was a significant improvement in putting success for both groups following practice (P = 0.001). Practising while visually focusing on the hole, resulted in a statistically significant reduction in putter speed variability in comparison to practising while visually focusing on the ball (P = 0.017). Visually focusing on the hole did not meaningfully (nor statistically) affect the quality of impact as assessed by the variability in face angle, stroke path, and impact spot at the precise moment the putter head contacted the ball.  相似文献   

4.
The purpose of this study was to examine the test-retest reliability, internal consistency and concurrent validity of the Athletic Skills Track (AST). During a regular PE lesson, 930 4- to 12-year old children (448 girls, 482 boys) completed two motor skill competence tests: (1) the Körperkoordination-Test für Kinder (KTK) and (2) an age-related version of the AST (age 4–6 years: AST-1, age 6–9 years: AST-2, and age 9–12 years: AST-3). The test-retest reliability of the AST was high (AST-1: ICC = 0.881 (95% CI: 0.780–0.934); AST-2: ICC = 0.802 (95% CI: 0.717–0.858); and AST-3: ICC = 0.800 (95% CI: 0.669–0.871). The internal consistency, concerning the three age-bands of the AST was above the acceptable level of Cronbach’s α > 0.70 (AST-1: α = 0.764; AST-2: α = 0.700; and AST-3: α = 0.763). There was a moderate to high correlation between the time to complete the AST, and the age- and gender-related motor quotients of the KTK (AST-1: r = ?0.747, p = 0.01; AST-2: r = ?0.646, p = 0.01; and AST-3: r = ?0.602, p = 0.01). The Athletic Skills Track is a reliable and valid assessment tool to assess motor skill competence among 4- to 12-year old children in the PE setting.  相似文献   

5.
In the golf instructional literature, the putting stroke is typically given higher priority than green reading and aiming. The main purpose of this study was to assess the importance of the putting stroke for direction consistency in golf putting. Kinematic stroke parameters were recorded from 71 elite golf players (mean handicap = 1.8, s = 4.2) on 1301 putts from about 4 m. Of the different factors deciding stroke direction consistency, face angle was found to be the most important (80%), followed by putter path (17%) and impact point (3%). This suggests that improvements in consistency of putter path and impact point will have very little effect on overall putting direction consistency and should not be prioritized in the training of elite players. In addition, mean stroke direction variability for an elite player (European Tour) was found to be 0.39 degrees, which is good enough to hole about 95% of all 4-m putts. In practice, however, top professionals in tournaments only hole about 17% of 4-m putts. We conclude that the putting stroke of elite golfers has a relatively minor influence on direction consistency.  相似文献   

6.
Groin injuries are common in soccer and often cause time-loss from training. While groin injuries have been linked to full effort kicking, the role of inside passing is unclear. Therefore, the purpose of this study was to investigate hip joint kinematics and muscle force, stress and contraction velocity for adductor longus and gracilis during inside passing. 3D kinematics of ten soccer players (23.4 yrs; 77.5 kg; 1.81 m) were captured with a motion capture system inside a Footbonaut. Muscle force and contraction velocity were determined with AnyBody Modelling System. Gracilis muscle forces were 9% lower compared to adductor longus (p = 0.005), but muscle stress was 183% higher in gracilis (p = 0.005). Contraction velocity reveals eccentric contraction of gracilis in the last quarter of the swing phase. Considering the combination of eccentric contraction, high muscle stress and the repetitive nature of inside passing, gracilis accumulates high loads in matches and training. These results indicate that the high incidence of groin injuries in soccer could be linked to isolated pass training. Practitioners need to be aware of the risk and refrain from sudden increases in the amount of pass training. This gives the musculoskeletal system time to adapt and might avoid career threatening injuries.  相似文献   

7.
The aim of this study was to explore the relationships between lower limb joint kinetics, external force production and starting block performance (normalised average horizontal power, NAHP). Seventeen male sprinters (100 m PB, 10.67 ± 0.32 s) performed maximal block starts from instrumented starting blocks (1000 Hz) whilst 3D kinematics (250 Hz) were also recorded during the block phase. Ankle, knee and hip resultant joint moment and power were calculated at the rear and front leg using inverse dynamics. Average horizontal force applied to the front (r = 0.46) and rear (r = 0.44) block explained 86% of the variance in NAHP. At the joint level, many “very likely” to “almost certain” relationships (r = 0.57 to 0.83) were found between joint kinetic data and the magnitude of horizontal force applied to each block although stepwise multiple regression revealed that 55% of the variance in NAHP was accounted for by rear ankle moment, front hip moment and front knee power. The current study provides novel insight into starting block performance and the relationships between lower limb joint kinetic and external kinetic data that can help inform physical and technical training practices for this skill.  相似文献   

8.
Abstract

The purpose of this study was to determine the validity and reliability of a new method for measuring three-dimensional (3D) putting stroke kinematics using the TOMI® device. A putting robot and a high-speed camera were used to simultaneously collect data for the validity evaluation. The TOMI® device, when used in conjunction with standard 3D coordinate data processing techniques, was found to be a valid and reliable method for measuring face angle, stroke path, putter speed, and impact spot at the moment of ball contact. The validity of the TOMI® measurement system was quantified using the 95% limits of agreement method for each aforementioned variable. The practical significance of each validity score was assessed by incorporating the maximum estimated measurement error into the stroke of the putting robot for 10 consecutive putts. All putts were executed from a distance of 4 m on a straight and flat synthetic putting surface. Since all putts were holed successfully, the measurement error for each variable was deemed to be negligible for the purposes of measuring putting stroke kinematics. The influence of key kinematic errors, at impact, on the outcome of a putt was also determined.  相似文献   

9.
Abstract

Although the effects of lateral biases in visual attention (“pseudoneglect”) have been examined in real-world settings, this phenomenon has yet to be considered within the realm of sporting performance. In the present study, we investigated the effects of pseudoneglect on putting errors in golf. Novice golfers (n = 30) performed 90 putting trials followed by a series of pseudoneglect tasks: requiring participants to bisect lines manually and with a biomechanical bisection tool. All pseudoneglect measures were performed with both the left and right hands. Results demonstrated a leftward bias for all the pseudoneglect tasks, and a rightward bias for putting error. Moreover, the results revealed that individuals who bisected lines to the left on the Bisection Tool (the typical class of pseudoneglect error for humans) with the left hand (the hand that typically produces the greatest pseudoneglect bias) displayed significantly smaller rightward putting errors. Moreover, these individuals also holed more putts. No other pseudoneglect tasks were shown to impact on putting performance. Our findings suggest that lateralized attentional biases have a significant effect on sport performance; they appear to influence a wide range of precision-based sports (e.g. shooting, archery). Findings are also discussed in terms of the processes that are likely to be involved in this effect.  相似文献   

10.
The present retrospective study intended to determine age, performance, the role of nationality and participation trends across calendar years in runners competing in “Comrades Marathon”, the ultra-marathon with the longest tradition and the highest number of finishers worldwide. We analysed 235,467 finishers (40,211 women and 195,256 men) competing between 1994 and 2017. In women and men, Russians were the fastest (12.55 ± 2.03 km/h and 12.24 ± 2.93 km/h, respectively) and Indians the slowest (7.87 ± 0.64 km/h and 7.91 ± 0.60 km/h) (p < 0.001, η2 = 0.053 and η2 = 0.010, small effect size, ES). Also, Russians were the youngest (33.9 ± 4.6 and 36.3 ± 5.9 years, respectively) and Japanese the oldest (49.3 ± 9.6 and 51.4 ± 12.3 years, respectively) (p < 0.001, η2 = 0.011, small ES). Performance improved (r = 0.90 in women and r = 0.92 in men), age of finishers (r = 0.91 in women and r = 0.97 in men), participation (r = 0.92 in women and r = 0.87 in men) and sex difference in age increased (r = 0.71), whereas men-to-women ratio (r = ?0.91) and sex difference in performance (r = ?0.68) decreased across calendar years (p < 0.001). In summary, runners from Russia were the fastest and the youngest in both sexes. The knowledge of the relationship of nationality with performance, age and participation trends of finishers, and changes across calendar years are of practical importance for ultra-runners and coaches working with them.  相似文献   

11.
Numerous skill batteries assess fundamental motor skill (e.g., kick, hop) competence. Few skill batteries examine lifelong physical activity skill competence (e.g., resistance training). This study aimed to develop and assess the content validity, test-retest and inter-rater reliability of the “Lifelong Physical Activity Skills Battery”. Development of the skill battery occurred in three stages: i) systematic reviews of lifelong physical activity participation rates and existing motor skill assessment tools, ii) practitioner consultation and iii) research expert consultation. The final battery included eight skills: grapevine, golf swing, jog, push-up, squat, tennis forehand, upward dog and warrior I. Adolescents (28 boys, 29 girls; M = 15.8 years, SD = 0.4 years) completed the Lifelong Physical Activity Skills Battery on two occasions two weeks apart. The skill battery was highly reliable (ICC = 0.84, 95% CI = 0.72–0.90) with individual skill reliability scores ranging from moderate (warrior I; ICC = 0.56) to high (tennis forehand; ICC = 0.82). Typical error (4.0; 95% CI 3.4–5.0) and proportional bias (r = ?0.21, p = .323) were low. This study has provided preliminary evidence for the content validity and reliability of the Lifelong Physical Activity Skills Battery in an adolescent population.  相似文献   

12.
Abstract

This study compared reactive agility between higher-standard (n = 14) and lower-standard (n = 14) Australian footballers using a reactive agility test incorporating a life-size video image of another player changing direction, including and excluding a feint. Mean agility time in the feint trials was 34% (509 ± 243 ms; p < 0.001; effect size 3.06) longer than non-feint trials. In higher-standard players, agility time was shorter than for lower-standard players in both feint (114 ± 140 ms; p = 0.18; effect size 0.52; likely beneficial) and non-feint (32 ± 44 ms; p = 0.22; effect size 0.47; possibly beneficial) trials. Additionally, the inclusion of a feint resulted in movement time increasing over three times more in the lower-standard group (197 ± 91 ms; p = 0.001; effect size 1.07; almost certainly detrimental) than the higher-standard group (62 ± 86 ms; p = 0.23; effect size 0.66; likely detrimental). There were weak correlations between the feint and non-feint trials (r = ?0.13–0.14; p > 0.05), suggesting that reactive agility involving a feint is a unique skill. Also, higher-standard players are more agile than their lower-standard peers, whose movement speed deteriorates more as task complexity increases with the inclusion of a feint. These results support the need for specific training in multi-turn reactive agility tasks.  相似文献   

13.
This study determined whether backward grinding performance in America's Cup sailing could be improved using a training intervention to increase power capability in the upper-body pull movement. Fourteen elite male sailors (34.9 ± 5.9 years; 98.1 ± 14.4 kg; 186.6 ± 7.7 cm) were allocated into experimental (speed-focussed) and control groups. Grinding performance was assessed using a grinding ergometer and an instrumented Smith machine measured force, velocity and power during the bench pull exercise. Conventional training produced significant improvements in bench pull 1 RM (5.2 ± 4.0%; p = 0.016) and maximum force production (5.4 ± 4.0%; p = 0.014). Speed-focussed training improved maximum power (7.8 ± 4.9%; p = 0.009), power at 1RM (10.3 ± 8.9%; p = 0.019) and maximum velocity (8.4 ± 2.6%; p = 0.0002). Backward grinding performance showed greater improvements in the experimental group than the control group for moderate (+1.8%) and heavy load (+6.0%) grinding. Changes in maximum power output and power at 1 RM had large correlations (r = 0.56–0.61) with changes in both moderate and heavy load grinding performance. Time to peak force had the strongest relationship, explaining 70% of the change in heavy load grinding performance. Although the performance benefit was not entirely clear the likelihood of a detrimental effect was low ( < 5%) and therefore implementation could be recommended.  相似文献   

14.
Carbohydrate (CHO) availability during endurance exercise seems to attenuate exercise-induced perturbations of cellular homeostasis and might consequently diminish the stimulus for training adaptation. Therefore, a negative effect of CHO intake on endurance training efficacy seems plausible. This study aimed to test the influence of carbohydrate intake on the efficacy of an endurance training program on previously untrained healthy adults. A randomized cross-over trial (8-week wash-out period) was conducted in 23 men and women with two 8-week training periods (with vs. without intake of 50g glucose before each training bout). Training intervention consisted of 4x45 min running/walking sessions/week at 70% of heart rate reserve. Exhaustive, ramp-shaped exercise tests with gas exchange measurements were conducted before and after each training period. Outcome measures were maximum oxygen uptake (VO2max) and ventilatory anaerobic threshold (VT). VO2max and VT increased after training regardless of CHO intake (VO2max: Non-CHO 2.6 ± 3.0 ml*min?1*kg?1 p = 0.004; CHO 1.4 ± 2.5 ml*min?1*kg?1 p = 0.049; VT: Non-CHO 4.2 ± 4.2 ml*min?1*kg?1 p < 0.001; CHO 3.0 ± 4.2 ml*min?1*kg?1 p = 0.003). The 95% confidence interval (CI) for the difference between conditions was between +0.1 and +2.1 ml*min?1*kg?1 for VO2max and between ?1.2 and +3.1 for VT. It is concluded that carbohydrate intake could potentially impair the efficacy of an endurance training program.  相似文献   

15.
ABSTRACT

The aim of this study was to identify the key kinematic parameters which contribute to higher spin rates in elite finger spin bowling. Kinematic data were collected for twenty-three elite male finger spin bowlers with thirty kinematic parameters calculated for each delivery. Stepwise linear regression and Pearson product moment correlations were used to identify kinematic parameters linked to spin rate. Pelvis orientation at front foot contact (r = 0.674, p < 0.001) and ball release (r = 0.676, p < 0.001) were found to be the biggest predictors of spin rate, with both individually predicting 43% of the observed variance in spin rate. Other kinematic parameters correlated with spin rate included: shoulder orientation at ball release (r = 0.462, p = 0.027), and pelvis-shoulder separation angle at front foot contact (r = 0.521, p = 0.011). The bowlers with the highest spin rates adopted a mid-way pelvis orientation angle, a larger pelvis-shoulder separation angle and a shoulder orientation short of side-on at front foot contact. The segments then rotated sequentially, starting with the pelvis and finishing with the pronation of the forearm. This knowledge can be translated to coaches to provide a better understanding of finger spin bowling technique.  相似文献   

16.
The purpose of this systematic review and meta-analysis is to assess the effect of concurrent high intensity interval training (HIIT) and resistance training (RT) on strength and hypertrophy. Five electronic databases were searched using terms related to HIIT, RT, and concurrent training. Effect size (ES), calculated as standardised differences in the means, were used to examine the effect of concurrent HIIT and RT compared to RT alone on muscle strength and hypertrophy. Sub-analyses were performed to assess region-specific strength and hypertrophy, HIIT modality (cycling versus running), and inter-modal rest responses. Compared to RT alone, concurrent HIIT and RT led to similar changes in muscle hypertrophy and upper body strength. Concurrent HIIT and RT resulted in a lower increase in lower body strength compared to RT alone (ES = ?0.248, p = 0.049). Sub analyses showed a trend for lower body strength to be negatively affected by cycling HIIT (ES = ?0.377, p = 0.074) and not running (ES = ?0.176, p = 0.261). Data suggests concurrent HIIT and RT does not negatively impact hypertrophy or upper body strength, and that any possible negative effect on lower body strength may be ameliorated by incorporating running based HIIT and longer inter-modal rest periods.  相似文献   

17.
Abstract

Omentin-1 is a newly discovered protein expressed and secreted from visceral adipose tissue that increases insulin sensitivity. We examined the effects of 12 weeks of aerobic training on serum omentin-1 concentrations together with cardiovascular risk factors in overweight and obese men. Eighteen overweight and obese participants (age 43.1 ± 4.7 years, BMI ≥25 kg · m?2) were assigned to exercise training (n = 9) and control (n = 9) groups. A matched control group of normal weight participants (n = 8; age 42.2 ± 3.8 years, BMI <25 kg · m?2) were also recruited for baseline comparison. The obese exercise group participated in 12 weeks of progressive aerobic training 5 days a week. Measures of serum omentin-1, insulin resistance, lipid profiles, blood pressure, and body composition were obtained before and after the 12 weeks. At baseline, normal weight participants had significantly higher serum omentin-1 concentrations than overweight and obese participants, and there were inverse correlations between omentin-1 and each of waist circumference, fasting glucose, insulin resistance, total cholesterol, triglyceride, and systolic blood pressure (P < 0.05). After the aerobic training, waist circumference, percent body fat, fasting glucose, insulin resistance, triglyceride, total cholesterol, low-density lipoprotein cholesterol, and systolic blood pressure were all significantly decreased (P < 0.05). In contrast, serum omentin-1 concentration was significantly increased after the aerobic programme (P < 0.05), and correlated with changes in insulin resistance (r = ?0.67, P = 0.04), glucose (r = ?0.65, P = 0.05), waist circumference (r = ?0.70, P = 0.03), and aerobic fitness r = ?0.68, P = 0.04). Aerobic training resulted in an improvement in cardiometabolic risk factors in obese participants, and this improvement was accompanied by increased omentin-1 concentrations.  相似文献   

18.
运用运动学研究方法对高尔夫球推杆头部技术动作进行量化分析,进而揭示推杆技术动作的运动学特征。对韩国釜山地区15名职业男子高尔夫运动员的推杆技术动作进行了研究,每名运动员在人工果岭上进行5次10.94m距离的推杆动作。运用三维技术动作分析系统(60Hz)对5次推杆动作的推杆头部进行了运动学分析。实验结果表明,推杆头部在各个区间的所需时间和移动距离都存在差异,在时间和空间上整个动作没有像钟摆一样摆动。  相似文献   

19.
Abstract

Previous studies on the kinematics of the golf swing have mainly focused on group analysis of male golfers of a wide ability range. In the present study, we investigated gross body kinematics using a novel method of analysis for golf research for a group of low handicap female golfers to provide an understanding of their swing mechanics in relation to performance. Data were collected for the drive swings of 16 golfers using a 12-camera three-dimensional motion capture system and a stereoscopic launch monitor. Analysis of covariance identified three covariates (increased pelvis–thorax differential at the top of the backswing, increased pelvis translation during the backswing, and a decrease in absolute backswing time) as determinants of the variance in clubhead speed (adjusted r 2 = 0.965, P < 0.05). A significant correlation was found between left-hand grip strength and clubhead speed (r = 0.54, P < 0.05) and between handicap and clubhead speed (r = ?0.612, P < 0.05). Flexibility measures showed some correlation with clubhead speed; both sitting flexibility tests gave positive correlations (clockwise: r = 0.522, P < 0.05; counterclockwise: r = 0.711, P < 0.01). The results suggest that there is no common driver swing technique for optimal performance in low handicap female golfers, and therefore consideration should be given to individual swing characteristics in future studies.  相似文献   

20.
Abstract

Transverse plane rotations of the upper body are often estimated during the golf swing. The aim of this study was to determine the agreement between upper body alignments measured using markers attached to the thorax and markers on the acromion process during the golf drive. Three-dimensional coordinate data from nine markers were collected (300 Hz) during eight golf drives for 10 participants. The transverse plane alignment of the upper body was calculated using three techniques: inter-acromion vector, thorax vector, and Cardan angles. Agreement between the methods was then assessed using intra-class correlation and 95% limits of agreement. Our results suggested that the thorax vector can be used to provide an accurate estimation of thorax alignment at all stages of the golf swing (R ≥ 0.97, systematic difference < 1.0°, random difference < 3.8°). The inter-acromion vector gave an accurate estimation of thorax alignment at address (R = 0.90, systematic difference = 0.0°, random difference = 4.3°) but it should not be used to estimate thorax alignment at the top of the backswing (R = 0.32, systematic difference = ?16.0°, random difference = 8.7°) or impact (R = 0.90, systematic difference = ?5.1°, random difference = 8.3°) during the golf drive.  相似文献   

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