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1.
Ahmed Attia Younes Hachana Helmi Chaabène Abdelmajid Gaddour Zied Neji Roy J. Shephard Mohamed Souhaiel Chelly 《PloS one》2014,9(12)
The intent of this study was to evaluate relative and absolute reliability of the 20-s anaerobic test (WAnT20) versus the WAnT30 and to verify how far the various indices of the 30-s Wingate anaerobic test (WAnT30) could be predicted from the WAnT20 data in male athletes. The participants were Exercise Science majors (age: 21.5±1.6 yrs, stature: 0.183±0.08 m, body mass: 81.2±10.9 kg) who participated regularly in team sports. In Phase I, 41 participants performed duplicate WAnT20 and WAnT30 tests to assess reliability. In Phase II, 31 participants performed one trial each of the WAnT20 and WAnT30 to determine the ability of the WAnT20 to predict components of the WAnT30. In Phase III, 31 participants were used to cross-validate the prediction equations developed in Phase II. Respective intra-class correlation coefficients (ICC) for peak power output (PPO) (ICC = 0.98 and 0.95) and mean power output (MPO) (ICC 0.98 and 0.90) did not differ significantly between WAnT20 and WAnT30. ICCs for minimal power output (POmin) and fatigue index (FI) were poor for both tests (range 0.53 to 0.76). Standard errors of the means (SEM) for PPO and MPO were less than their smallest worthwhile changes (SWC) in both tests; however, POmin and FI values were “marginal,” with SEM values greater than their respective SWCs for both tests values. Stepwise regression analysis showed that MPO had the highest coefficient of predictability (R = 0.97), with POmin and FI considerable lower (R = 0.71 and 0.41 respectively). Cross-validation showed insignificant bias with limits of agreement of 0.99±1.04, 6.5±92.7 W, and 1.6±9.8% between measured and predicted MPO, POmin, and FI, respectively. WAnT20 offers a reliable and valid test of leg anaerobic power in male athletes and could replace the classic WAnT30. 相似文献
2.
Stickley CD Hetzler RK Kimura IF 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(3):958-965
The traditional 30-second Wingate anaerobic test (WAnT) is a widely used anaerobic power assessment protocol. An abbreviated protocol has been shown to decrease the mild to severe physical discomfort often associated with the WAnT. Therefore, the purpose of this study was to determine whether a 20-second WAnT protocol could be used to accurately predict power values of a standard 30-second WAnT. In 96 college females, anaerobic power variables were assessed using a standard 30-second WAnT protocol. Maximum power values as well as instantaneous power at 10, 15, and 20 seconds were recorded. Based on these results, stepwise regression analysis was performed to determine the accuracy with which mean power, minimum power, 30-second power, and percentage of fatigue for a standard 30-second WAnT could be predicted from values obtained during the first 20 seconds of testing. Mean power values showed the highest level of predictability (R2 = 0.99) from the 20-second values. Minimum power, 30-second power, and percentage of fatigue also showed high levels of predictability (R2 = 0.91, 0.84, and 0.84, respectively) using only values obtained during the first 20 seconds of the protocol. An abbreviated (20-second) WAnT protocol appears to effectively predict results of a standard 30-second WAnT in college-age females, allowing for comparison of data to published norms. A shortened test may allow for a decrease in unwanted side effects associated with the traditional WAnT protocol. 相似文献
3.
Negrete RJ Hanney WJ Kolber MJ Davies GJ Ansley MK McBride AB Overstreet AL 《Journal of strength and conditioning research / National Strength & Conditioning Association》2010,24(12):3318-3325
The purpose of this study was to examine the test-retest reliability, minimal detectable change (MDC), and determine normative values of 3 upper extremity (UE) tests of function and power. One hundred eighty participants, men (n = 69) and women (n = 111), were tested on 3 UE strength and power maneuvers in a multicenter study to determine baseline normative values. Forty-six subjects returned for a second day of testing within 5 days of the initial assessment for the reliability component of the investigation. Explosive power was assessed via a seated shot-put test for the dominant and nondominant arms. Relationships between the dominant and nondominant arms were also analyzed. A push-up and modified pull-up were performed to measure the amount of work performed in short (15-second) bursts of activity. The relationship between the push-up and modified pull-up was also determined. Analysis showed test-retest reliability for the modified pull-up, timed push-up, dominant single-arm seated shot-put tests, and nondominant single-arm seated shot-put tests to be intraclass correlation coefficient(3,1) 0.958, 0.989, 0.988, and 0.971, respectively. The MDC for both the push-up and modified pull-up was 2 repetitions. The MDCs for the shot put with the dominant arm and the nondominant arm were 17 and 18 in., respectively. The result of this study indicates that these field tests possess excellent reliability. Normative values have been identified, which require further validation. These tests demonstrate a practical and effective method to measure upper extremity functional power. 相似文献
4.
Sands WA McNeal JR Ochi MT Urbanek TL Jemni M Stone MH 《Journal of strength and conditioning research / National Strength & Conditioning Association》2004,18(4):810-815
The purpose of this study was to compare the Wingate cycling and Bosco repeated jumps anaerobic tests. Eleven men (21.36 +/- 1.6 years; 179.1 +/- 9.3 cm; 78.7 +/- 11.0 kg) and 9 women (21.89 +/- 3.66 years; 171.8 +/- 10.0 cm; 75.9 +/- 21.4 kg), all university athletes, volunteered to participate. Subjects performed each test in random order. The tests consisted of a 30-second Wingate test and a 60-second Bosco test. The Wingate test was conducted using a Monark cycle ergometer and the Bosco test was conducted on a force platform. Following the performance of each test, peak lactate concentrations were determined. Average and peak power values were statistically greater in men and on the Bosco test. Peak lactate values were statistically greater in men but did not differ based on test. Correlations between peak lactate concentrations between tests and lactate values with peak or average power were not statistically significant. The relationship between peak power between tests was statistically significant among men, but not women. The results of the study indicated that the Bosco and Wingate tests, which both measure anaerobic characteristics, appear to measure different aspects of anaerobic power and capacity. The Bosco test also may be inappropriate for athletes who are not well trained in jumping. 相似文献
5.
Taylor JD Bandy WD Whittemore JD 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(5):1465-1469
Measurement of graded exercise test duration is clinically important and can be assessed by maximal graded exercise testing. Yet, limitations of maximal graded exercise testing exist. An alternative to maximal graded exercise testing is submaximal graded exercise testing. However, no studies have investigated the reliability of a submaximal graded exercise test in the measurement of graded exercise test duration. The purpose of this study was to determine the test-retest reliability and minimal detectable change (MDC) of a novel submaximal graded exercise test in the measurement of graded exercise test duration. Fifteen people (4 men, 11 women) with a mean age of 26.20 years (SD = 9.04) participated in this study. A novel submaximal graded exercise test was used to measure graded exercise test duration for each participant. Endpoints of the test were either 85% of age-predicted maximum heart rate or voluntarily stopping the test, whichever endpoint occurred first. Heart rate and graded exercise test duration were constantly measured throughout the test. Graded exercise test duration was defined as the total duration (minutes) of the test. For all participants, the submaximal graded exercise test was conducted at baseline and 48-72 hours thereafter. The intraclass correlation coefficient for the test-retest reliability of the test in determining graded exercise test duration was 0.94 (95% CI = 0.83-0.98). The MDC of the test in the measurement of graded exercise test duration was 0.86 minutes. The results suggest that clinicians can use this novel submaximal graded exercise test to reliably measure graded exercise test duration with a measurement error, as expressed by the MDC, of 0.86 minutes. 相似文献
6.
Lorino AJ Lloyd LK Crixell SH Walker JL 《Journal of strength and conditioning research / National Strength & Conditioning Association》2006,20(4):851-854
Caffeine has been shown to improve sprint time, anaerobic power, and reaction time, all integral aspects of agility. The purpose of this study was to determine whether an acute caffeine dose would enhance agility and anaerobic power. Sixteen subjects participated in a randomized, double-blind experiment and performed the proagility run and the 30-second Wingate test 60 minutes after ingestion of caffeine (6 mg.kg(-1)) or placebo. No significant change was observed in the proagility run after caffeine ingestion compared with placebo. Also, no significant change was observed in peak power, mean power, or percent power decrease. Agility is an integral component of athletic skill and any reasonable method for enhancing agility would benefit active individuals. However, results from this study indicate that a 6 mg.kg(-1) dose of caffeine does not impact agility as measured by the proagility run test or power output as measured by the 30-second Wingate test in recreationally active young adult males who are not habituated to caffeine. 相似文献
7.
Glaister M Stone MH Stewart AM Hughes M Moir GL 《Journal of strength and conditioning research / National Strength & Conditioning Association》2003,17(4):781-784
The aims of the present study were: (a) to determine the number of familiarization trials required to establish a high degree of reliability in measures of power output during maximal intermittent cycling; and (b) to examine the reliability of those same measures after familiarization had been established. On separate days over a 3-week period, 2 groups of 7 recreationally active men completed 8 trials of 1 of 2 maximal (20 x 5-second) intermittent cycling tests with contrasting recovery periods (10-seconds or 30-seconds). Significant (p < 0.05) between-trial differences were detected in post-hoc tests involving trials 1 and 2 only. Within-subject test-retest reliability was therefore assessed across trials 3-8. Apart from values of maximum power output in Protocol 1 (10-second recovery periods), all remaining measures of power output showed high degrees of within-subject test-retest reliability (coefficient of variation: 2.4-3.7%). The results of the present study indicate that in subjects unfamiliar with maximal intermittent cycling, high degrees of reliability in many performance measures can be achieved following the completion of 2 familiarization trials. 相似文献
8.
Lim JM Chia MY 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(3):993-996
There is limited evidence that the nonmotorized treadmill (NMT) test is able to elicit peak power (PP) and mean power (MP) reliably for high-intensity and short-duration exercises in untrained adults. This study aimed to establish the intra- and intersession reliability of PP and MP derived from the NMT test. Nine untrained men and 9 untrained women participated in the study. They completed 2 sessions of a 10-second NMT test on 2 separate occasions that were scheduled 2 weeks apart (intersession test). Each session consisted of 2 sprints (intrasession test). On the third session, the subjects performed two 30-second Wingate Anaerobic Tests. Inter- and intrasession power measurements were analyzed using repeatability coefficient, typical error, coefficient of variation, change in the mean, and Pearson correlation coefficient. Inter- and intrasession measurements using these statistical tests all showed high reliability of the results. The study clearly showed that PP and MP measurements derived from the NMT test was just as reliable as the current "gold standard." 相似文献
9.
Farzad B Gharakhanlou R Agha-Alinejad H Curby DG Bayati M Bahraminejad M Mäestu J 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(9):2392-2399
Increasing the level of physical fitness for competition is the primary goal of any conditioning program for wrestlers. Wrestlers often need to peak for competitions several times over an annual training cycle. Additionally, the scheduling of these competitions does not always match an ideal periodization plan and may require a modified training program to achieve a high level of competitive fitness in a short-time frame. The purpose of this study was to examine the effects of 4 weeks of sprint-interval training (SIT) program, on selected aerobic and anaerobic performance indices, and hormonal and hematological adaptations, when added to the traditional Iranian training of wrestlers in their preseason phase. Fifteen trained wrestlers were assigned to either an experimental (EXP) or a control (CON) group. Both groups followed a traditional preparation phase consisting of learning and drilling technique, live wrestling and weight training for 4 weeks. In addition, the EXP group performed a running-based SIT protocol. The SIT consisted of 6 35-m sprints at maximum effort with a 10-second recovery between each sprint. The SIT protocol was performed in 2 sessions per week, for the 4 weeks of the study. Before and after the 4-week training program, pre and posttesting was performed on each subject on the following: a graded exercise test (GXT) to determine VO(2)max, the velocity associated with V(2)max (νVO(2)max), maximal ventilation, and peak oxygen pulse; a time to exhaustion test (T(max)) at their νVO(2)max; and 4 successive Wingate tests with a 4-minute recovery between each trial for the determination of peak and mean power output (PPO, MPO). Resting blood samples were also collected at the beginning of each pre and posttesting period, before and after the 4-week training program. The EXP group showed significant improvements in VO(2)max (+5.4%), peak oxygen pulse (+7.7%) and T(max) (+32.2%) compared with pretesting. The EXP group produced significant increases in PPO and MPO during the Wingate testing compared with pretesting (p < 0.05). After the 4-week training program, total testosterone and the total testosterone/cortisol ratio increased significantly in the EXP group, whereas cortisol tended to decrease (p = 0.06). The current findings indicate that the addition of an SIT program with short recovery can improve both aerobic and anaerobic performances in trained wrestlers during the preseason phase. The hormonal changes seen suggest training-induced anabolic adaptations. 相似文献
10.
Arslan C 《Journal of strength and conditioning research / National Strength & Conditioning Association》2005,19(3):658-666
The aim of this study was to investigate a possible relation between power performance of the Wingate test (WT) and isometric leg strength (ILS) and explosive leg strength (ELS) characteristics in young men and women with different physical fitness levels. A total of 166 subjects, including 98 young men and 68 young women, were included in the study. The subjects were divided into a regular exercise group and a sedentary group. The physical and body mass index characteristics of the subjects were not different, and they had not taken part in the directed jumping. When the regular exercise and sedentary groups were considered together with men, women, and total population groups, no significant correlation existed between WT anaerobic fatigue index and ILS and ELS (p > 0.05), but significant positive correlations existed among peak power, peak power per weight, mean power, mean power per weight, and WT power, which were recorded in 5-second intervals (p < 0.001). Although the 5-second WT parameters were significantly correlated with ILS and ELS for the first 15-second period, this correlation was more pronounced for the last 15 seconds for all groups (p < 0.01). As a result, this study indicated that regular physical activity has a positive significant relation on WT power, ILS, and ELS in both sedentary men and women and those engaged in regular sports activities. 相似文献
11.
Inoue A Sá Filho AS Mello FC Santos TM 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(6):1589-1593
Despite its apparent relevance, there is no evidence supporting the importance of anaerobic metabolism in Olympic crosscountry mountain biking (XCO). The purpose of this study was to examine the correlation between XCO race time and performance indicators of anaerobic power. Ten XCO riders (age: 28 ± 5 years; weight: 68.7 ± 7.7 kg; height: 177.9 ± 7.4 cm; estimated body fat: 5.7 ± 2.8%; estimated ·VO?max: 68.4 ± 5.7 ml·kg?1·min?1) participating in the Lagos Mountain Bike Championship (Brazil) completed 2 separate testing sessions before the race. In the first session, after anthropometric assessments were performed, the cyclists completed a single 30-second Wingate (WIN) test and an intermittent tests consisting of 5 × 30-second WIN tests (50% of the single WIN load) with 30 seconds of recovery between trials. In the second session, the riders performed a maximal incremental test. A significant correlation was found between race time and maximal power on the 5× WIN test (r = -0.79, IC(95%) -0.94 to -0.32, p = 0.006) and the mean average power on the 5× WIN test normalized by body mass (r = -0.63, IC(95%) -0.90 to -0.01, p = 0.048). The finding of the study supports the use of anaerobic tests for assessing mountain bikers participating in XCO competitions and suggests that anaerobic power is an important determinant of performance. 相似文献
12.
Morin JB Dupuy J Samozino P 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(7):1918-1924
When testing the ability of sportsmen to repeat maximal intensity efforts, or when designing specific training exercises to improve it, fatigue during repeated sprints is usually investigated through a number of sprints identical for all subjects, which induces a high intersubject variability in performance decrement in a typical heterogeneous group of athletes (e.g., team sport group, students, and research protocol volunteers). Our aim was to quantify the amplitude of the reduction in this variability when individualizing the sprint dose, that is, when requiring subjects to perform the number of sprints necessary to reach a target level of performance decrement. Fifteen healthy men performed 6-second sprints on a cycle ergometer with 24 seconds of rest until exhaustion or until 20 repetitions in case no failure occurred. Peak power output (PPO) was measured and a fatigue index (FI) computed. The variability in PPO decrement was compared between the 10th sprint and the sprint at which subject reached the target FI of 10%. Individual FI values after the 10th sprint were 14.6 ± 6.9 vs. 11.1 ± 1.2%, when individualizing the sprint dose, which corresponded to coefficients of interindividual variability of ~47.3 and ~10.8%, respectively. Individualizing the sprint dose substantially reduced intersubject variability in performance decrement, enabling a more standardized state of fatigue in repeated-sprints protocols designed to induce fatigue and test or train this specific repeated-sprint ability in a heterogeneous group of athletes. A direct feedback on the values of performance parameters is necessary between each sprint for the experimenter to set this individualized sprint dose. 相似文献
13.
Thatcher R Gifford R Howatson G 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(11):3089-3094
ABSTRACT: Thatcher, R, Gifford, R, and Howatson, G. The influence of recovery duration after heavy resistance exercise on sprint cycling performance. J Strength Cond Res 26(11): 3089-3094, 2012-The aim of this study was to determine the optimal recovery duration after prior heavy resistance exercise (PHRE) when performing sprint cycling. On 5 occasions, separated by a minimum of 48 hours, 10 healthy male subjects (mean ± SD), age 25.5 ± 7.7 years, body mass 82.1 ± 9.0 kg, stature 182.6 ± 87 cm, deadlift 1-repetition maximum (1RM) 142 ± 19 kg performed a 30-second sprint cycling test. Each trial had either a 5-, 10-, 20-, or 30-minute recovery after a heavy resistance activity (5 deadlift repetitions at 85% 1RM) or a control trial with no PHRE in random order. Sprint cycling performance was assessed by peak power (PP), fatigue index, and mean power output over the first 5 seconds (MPO5), 10 seconds (MPO10), and 30 seconds (MPO30). One-way analysis of variance with repeated measures followed by paired t-tests with a Bonferroni adjustment was used to analyze data. Peak power, MPO5, and MPO10 were all significantly different during the 10-minute recovery trial to that of the control condition with values of 109, 112, and 109% of control, respectively; no difference was found for the MPO30 between trials. This study supports the use of PHRE as a strategy to improve short duration, up to, or around 10-second, sprint activity but not longer duration sprints, and a 10-minute recovery appears to be optimal to maximize performance. 相似文献
14.
Sirotic AC Coutts AJ 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(1):138-144
A large number of team sports require athletes to repeatedly produce maximal or near maximal sprint efforts of short duration interspersed with longer recovery periods of submaximal intensity. This type of team sport activity can be characterized as prolonged, high-intensity, intermittent running (PHIIR). The primary purpose of the present study was to determine the physiological factors that best relate to a generic PHIIR simulation that reflects team sport running activity. The second purpose of this study was to determine the relationship between common performance tests and the generic PHIIR simulation. Following a familiarization session, 16 moderately trained (VO2max = 40.0 +/- 4.3 ml x kg(-1) x min(-1)) women team sport athletes performed various physiological, anthropometrical, and performance tests and a 30-minute PHIIR sport simulation on a nonmotorized treadmill. The mean heart rate and blood lactate concentration during the PHIIR sport simulation were 164 +/- 6 b x min(-1) and 8.2 +/- 3.3 mmol x L(-1), respectively. Linear regression demonstrated significant relationships between the PHIIR sport simulation distance and running velocity attained at a blood lactate concentration of 4 mmol x L(-1) (LT) (r = 0.77, p < 0.05), 5 x 6-second repeated cycle sprint work (r = 0.56, p < 0.05), 30-second Wingate test (r = 0.61, p < 0.05), peak aerobic running velocity (Vmax) (r = 0.69, p < 0.05), and Yo-Yo Intermittent Recovery Test (Yo-Yo IR1) distance (r = 0.50, p < 0.05), respectively. These results indicate that an increased LT is associated with improved PHIIR performance and that PHIIR performance may be monitored by determining Yo-Yo IR1 performance, 5 x 6-second repeated sprint cycle test work, 30-second Wingate test performance, Vmax, or LT. We suggest that training programs should focus on improving both LT and Vmax for increasing PHIIR performance in moderately trained women. Future studies should examine optimal training methods for improving these capacities in team sport athletes. 相似文献
15.
Ozkaya O Colakoglu M Kuzucu EO Yildiztepe E 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(5):1313-1323
The 30-second, all-out Wingate test evaluates anaerobic performance using an upper or lower body cycle ergometer (cycle Wingate test). A recent study showed that using a modified electromagnetically braked elliptical trainer for Wingate testing (EWT) leads to greater power outcomes because of larger muscle group recruitment. The main purpose of this study was to modify an elliptical trainer using an easily understandable mechanical brake system instead of an electromagnetically braked modification. Our secondary aim was to determine a proper test load for the EWT to reveal the most efficient anaerobic test outcomes such as peak power (PP), average power (AP), minimum power (MP), power drop (PD), and fatigue index ratio (FI%) and to evaluate the retest reliability of the selected test load. Delta lactate responses (ΔLa) were also analyzed to confirm all the anaerobic performance of the athletes. Thirty healthy and well-trained male university athletes were selected to participate in the study. By analysis of variance, an 18% body mass workload yielded significantly greater test outcomes (PP = 19.5 ± 2.4 W·kg, AP = 13.7 ± 1.7 W·kg, PD = 27.9 ± 5 W·s, FI% = 58.4 ± 3.3%, and ΔLa = 15.4 ± 1.7 mM) than the other (12-24% body mass) tested loads (p < 0.05). Test and retest results for relative PP, AP, MP, PD, FI%, and ΔLa were highly correlated (r = 0.97, 0.98, 0.94, 0.91, 0.81, and 0.95, respectively). In conclusion, it was found that the mechanically braked modification of an elliptical trainer successfully estimated anaerobic power and capacity. A workload of 18% body mass was optimal for measuring maximal and reliable anaerobic power outcomes. Anaerobic testing using an EWT may be more useful to athletes and coaches than traditional cycle ergometers because a greater proportion of muscle groups are worked during exercise on an elliptical trainer. 相似文献
16.
Rana SR 《Journal of strength and conditioning research / National Strength & Conditioning Association》2006,20(2):292-297
The purpose of this investigation was to examine mechanomyographic (MMG) and electromyographic (EMG) amplitude responses of the superficial quadriceps femoris muscles during the Wingate Anaerobic Test (WAnT). Ten healthy adults (age 21 +/- 1.2 years) volunteered to perform the WAnT on a calibrated Monark 894E cycle ergometer while the EMG and MMG signals were recorded. The EMG and MMG amplitude and power output (W) values per 5-second segments of the test were averaged and normalized to the highest value found during the test, respectively. The statistical analysis indicated that EMG amplitude did not change significantly over the 30-second test, but W and MMG amplitude decreased significantly. There is dissociation between EMG and MMG amplitude over the 30-second anaerobic test, providing evidence that MMG amplitude could be used as a monitor of W during such a task. MMG amplitude could potentially be used as a direct monitor of mechanical activity, which could be of benefit to those who train athletes when a direct assessment of mechanical contribution from a given muscle to a fatiguing activity is desired (such as when monitoring an injury), but it must be studied under various conditions, such as the current study, before such applications are made. 相似文献
17.
18.
Mohammad Al-Amri Hilal Al Balushi Abdulrhman Mashabi 《Computer methods in biomechanics and biomedical engineering》2017,20(16):1669-1677
Self-paced treadmill walking is becoming increasingly popular for the gait assessment and re-education, in both research and clinical settings. Its day-to-day repeatability is yet to be established. This study scrutinised the test-retest repeatability of key gait parameters, obtained from the Gait Real-time Analysis Interactive Lab (GRAIL) system. Twenty-three male able-bodied adults (age: 34.56 ± 5.12 years) completed two separate gait assessments on the GRAIL system, separated by 5 ± 3 days. Key gait kinematic, kinetic, and spatial-temporal parameters were analysed. The Intraclass-Correlation Coefficients (ICC), Standard Error Measurement (SEM), Minimum Detectable Change (MDC), and the 95% limits of agreements were calculated to evaluate the repeatability of these gait parameters. Day-to-day agreements were excellent (ICCs > 0.87) for spatial-temporal parameters with low MDC and SEM values, <0.153 and <0.055, respectively. The repeatability was higher for joint kinetic than kinematic parameters, as reflected in small values of SEM (<0.13 Nm/kg and <3.4°) and MDC (<0.335 Nm/kg and <9.44°). The obtained values of all parameters fell within the 95% limits of agreement. Our findings demonstrate the repeatability of the GRAIL system available in our laboratory. The SEM and MDC values can be used to assist researchers and clinicians to distinguish ‘real’ changes in gait performance over time. 相似文献
19.
The traditional warm-up (WU) used by athletes to prepare for a sprint track cycling event involves a general WU followed by a series of brief sprints lasting ≥ 50 min in total. A WU of this duration and intensity could cause significant fatigue and impair subsequent performance. The purpose of this research was to compare a traditional WU with an experimental WU and examine the consequences of traditional and experimental WU on the 30-s Wingate test and electrically elicited twitch contractions. The traditional WU began with 20 min of cycling with a gradual intensity increase from 60% to 95% of maximal heart rate; then four sprints were performed at 8-min intervals. The experimental WU was shorter with less high-intensity exercise: intensity increased from 60% to 70% of maximal heart rate over 15 min; then just one sprint was performed. The Wingate test was conducted with a 1-min lead-in at 80% of optimal cadence followed by a Wingate test at optimal cadence. Peak active twitch torque was significantly lower after the traditional than experimental WU (86.5 ± 3.3% vs. 94.6 ± 2.4%, P < 0.05) when expressed as percentage of pre-WU amplitude. Wingate test performance was significantly better (P < 0.01) after experimental WU (peak power output = 1,390 ± 80 W, work = 29.1 ± 1.2 kJ) than traditional WU (peak power output = 1,303 ± 89 W, work = 27.7 ± 1.2 kJ). The traditional track cyclist's WU results in significant fatigue, which corresponds with impaired peak power output. A shorter and lower-intensity WU permits a better performance. 相似文献
20.
Buchheit M Lefebvre B Laursen PB Ahmaidi S 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(5):1457-1464
The purpose of this study was to examine the reliability, usefulness, and validity of the 30-15 Intermittent Ice Test (30-15(IIT)) in 17 young elite ice hockey players. For the reliability and usefulness study, players performed the 30-15(IIT) 7 days apart. For the validity study, data derived from the first 30-15(IIT) were compared with those obtained from the 30-15 Intermittent Fitness Test (30-15(IFT), the running version of this test used as a reference marker for its ability to assess cardiovascular fitness in the field, that is, VO?peak). Maximal speed, heart rate at exhaustion (HR(peak)) and postexercise blood-lactate levels ([La](b)) were collected for all tests, whereas submaximal HR was taken at stages 4 and 8 (HR(stage4) and HR(stage8)) during the 30-15(IIT). All intra-class correlation coefficients were >0.94. Coefficients of variation were 1.6% (90% CI, 1.3-2.3), 1.7% (1.3-2.8), 1.4% (1.0-2.2), and 0.7% (0.5-1.1) for maximal skating speed, HR(stage4), HR(stage8), and HR(peak), respectively. Correlations between maximal velocities and HR(peak) obtained for the 30-15(IIT) vs. 30-15(IFT) were very large (r = 0.72) and large (r = 0.61), respectively. Maximal skating speed was also largely correlated to estimated VO?peak (r = 0.71). There was however no correlation for [La](b) values between both tests (r = 0.42). These results highlight the specificity of the on-ice 30-15(IIT) and show it to be a reliable and valid test for assessing cardiorespiratory fitness in young elite players. Coaches could interpret a change in performance of at least 2 stages, or a change in submaximal HR of more than 8% (≈8 b·min?1) during the eighth stage to be a meaningful change in skating fitness. 相似文献