Influence of testing sequence on a child's ability to achieve maximal anaerobic and aerobic power

The aim of the study was to examine the order of testing sequence on a child's ability to achieve maximal anaerobic and aerobic power. Thirty-two children (20 females, 12 males) between 7 - 11 years of age participated in this study. All subjects were tested on three separate occasions as follows: anaerobic power session - Wingate Anaerobic Test (WAnT) only; aerobic power session - maximal oxygen consumption (V.O (2max)) test only; and experimental session - WAnT followed by a V.O (2max) test (WAnT/V.O (2max)) or a V.O (2max) test followed by a WAnT (V.O (2max)/WAnT), each with 20 minutes of rest between the assessments. No significant differences were observed between the baseline WAnT or V.O (2max) between the two groups. No significant differences were observed for WAnT power values in either group regardless of testing sequence. Children in the WAnT/V.O (2max) group had significantly lower experimental V.O (2max) (38.6 +/- 7.6 vs. 40.6 +/- 7.4 mL . kg (-1) . min (-1); p < 0.05), RER (1.10 +/- 0.08 vs. 1.13 +/- 0.07; p < 0.05), and exercise time (472 +/- 87 vs. 511 +/- 79 s; p < 0.01) values when compared to the baseline V.O (2max) test. The results of this study indicate that when assessing a child's anaerobic and aerobic power during the same testing session, the testing sequence is of importance. However, it appears that a V.O (2max) test can be performed 20 minutes prior to the WAnT without affecting anaerobic power in children.     

Field test evaluation of aerobic, anaerobic, and wheelchair basketball skill performances

Forty-six male wheelchair basketball players performed a set of field tests to evaluate aerobic capacity (25 m shuttle run), anaerobic capacity (30s sprint), and six specific wheelchair basketball skills. Overall test-retest reliability (n = 20) ranged from r = 0.65 to r = 0.97. To study the validity (criterion related evidence) of the shuttle run test, heart rate (HR) was recorded for 15 subjects, who also performed a continuous, multistage arm cranking exercise until volitional fatigue. Moderate to high correlations were calculated between shuttle run distances covered (1375 243,6 m) and VO2max (2208+/-461.6 mL/min) and POmax (93.8+/-17.97 W), measured during maximal arm cranking (respectively r = 0.64 and r = 0.87). Maximal HR during shuttle run (174.9+/-16.6 B/min) and arm cranking (169+/-14.21 B/min) were correlated (r = 0.78). High correlations between shuttle run test and anaerobic field tests, however, indicate high implication of anaerobic and wheelchair maneuverability performances. The 30 s sprint test was validated (n = 15) against a Wingate Anaerobic Test (WAnT) on a roller ergometer. Comparing distance (field test: 90+/-6.7 m) with mean power output (WAnT: 852.1+/-234.9 W) the correlation was r = 0.93. Principal components factor analysis identified 'wheelchair propulsion dynamics' and 'eye-hand-coordination' as the underlying constructs of the six skill proficiency measurements, accounting for 80.1% of the variance. In conclusion, the newly developed field test battery is a reliable and valid tool for anaerobic capacity and skill proficiency assessment in wheelchair basketball players.     

Comparison of human impact response in restraint systems with and without a negative G strap

A test program to assess the influence of a negative G strap on restraint dynamics and human impact response was conducted at AFAMRL. There were 131 experimental-level impact tests with volunteer subjects performed in eight different test conditions. Forward-facing (-Gx) impacts were carried out on a horizontal accelerator, while vertical (+Gz) impact tests were done on a vertical drop tower facility. In both axes, the experimental exposure was an approximate half-sine waveform with peak acceleration up to 10 G and velocity change up to 9.2 m X s-1. Subjects were restrained to the test vehicle using either the PCU-15/P torso harness and lap belt, which is used operationally in such aircraft as the A-20 and F-15, or a conventional double shoulder strap and lap belt configuration. In one half of the test conditions, fixed-length negative G straps were incorporated into these restraint systems. In the other test conditions, the unmodified restraint systems were evaluated. Adding the negative G strap to either restraint system had clearly beneficial effects. These included decreasing the tendency toward submarining in forward-facing impacts, providing better occupant-seat coupling during free falls, and improving vertical impact protection. Sufficient benefits appear to result from use of the negative G strap to warrant a recommendation for its incorporation into selected USAF restraint systems, such as the PCU-15/P torso harness and lap belt. Additional data analysis revealed that the conventional double shoulder strap and lap belt restraint provided better forward-facing and vertical impact protection than the PCU-15/P torso harness and lap belt configuration. Further research at AFAMRL is planned to identify restraint harness features which may improve the performance of current and future impact protection systems.     

A simple multistage field test for the prediction of anaerobic capacity in female games players

Objective: To establish the validity of a 15 m multistage shuttle run test (MSRT) as a predictor of anaerobic capacity (expressed as mean power output (MPO) from the 30 second Wingate anaerobic test (WAnT)) in female university standard games players.     

Energy metabolism during anaerobic exercise in children with cystic fibrosis and asthma.

PURPOSE: The nature of a child's daily physical activity requires both aerobic and anaerobic energy metabolism. Aerobic exercise becomes compromised with advancing airway obstruction in children with cystic fibrosis (CF) and asthma (AS). Whether children with CF will have altered metabolic responses to supramaximal exercise when compared with asthmatics or healthy controls is still undetermined. METHODS: Twenty-five children with CF, 22 with AS, and 23 healthy controls (CN) performed an incremental graded aerobic and Wingate anaerobic test (WAnT) on a cycle ergometer. Analysis of gas exchange and ventilatory data was collected and averaged every 5 s to estimate ventilatory kinetics and energy system contributions during both tests. RESULTS: The CF and AS groups had mild lower airway obstruction (FEF25-75% < 80%) as compared with the CN. All three groups demonstrated similar anaerobic (mean and peak power during the WAnT) and aerobic exercise performance (peak oxygen consumption). In contrast to the AS or CN groups, children with CF used a lower percentage of their peak VO2 and V(E) during each phase of the WAnT, suggesting a preferential use of ATP/phosphocreatine and glycolytic energy stores compared with aerobic pathways. Greater reliance on anaerobic pathways during the WAnT in children with CF could be due to the physiologic sequelae underlying chronic obstructive lung disease. CONCLUSIONS: Oxygen uptake kinetics appeared similar for all three groups. Although the energy needed to perform the WAnT can be met by subjects with CF, abnormalities in energy metabolism may exist for this group during exercise.     

Standard anaerobic exercise tests

Anaerobic tests are divided into tests measuring anaerobic power and anaerobic capacity. Anaerobic power tests include force-velocity tests, vertical jump tests, staircase tests, and cycle ergometer tests. The values of maximal anaerobic power obtained with these different protocols are different but generally well correlated. Differences between tests include factors such as whether average power or instantaneous power is measured, active muscle mass is the same in all the protocols, the legs act simultaneously or successively, maximal power is measured at the very beginning of exercise or after several seconds, inertia of the devices and body segments are taken into account. Force-velocity tests have the advantage of enabling the estimation of the force and velocity components of power, which is not possible with tests such as a staircase test, a vertical jump, the Wingate test and other long-duration cycle ergometer protocols. Maximal anaerobic capacity tests are subdivided into maximal oxygen debt test, ergometric tests (all-out tests and constant load tests), measurement of oxygen deficit during a constant load test and measurement of peak blood lactate. The measurement of the maximal oxygen debt is not valid and reliable enough to be used as an anaerobic capacity test. The aerobic metabolism involvement during anaerobic capacity tests, and the ignorance of the mechanical efficiency, limit the validity of the ergometric tests which are only based on the measurement of work. The amount of work performed during the Wingate test depends probably on glycolytic and aerobic power as well as anaerobic capacity. The fatigue index (power decrease) of the all-out tests is not reliable and depends probably on aerobic power as well as the fast-twich fibre percentage. Reliability of the constant load tests has seldom been studied and has been found to be rather low. In theory, the measure of the oxygen deficit during a constant load test is more valid than the other tests but its reliability is unknown. The validity and reliability of postexercise blood lactate as a test of maximal anaerobic capacity are probably not better than that of the current erogmetric tests. The choice of an anaerobic test depends on the aims and subjects of a study and its practicability within a testing session.     

Anaerobic power and muscle strength in young hemophilia patients

PURPOSE: The purpose of this study was to evaluate muscle strength and anaerobic power in young boys with hemophilia compared with healthy boys. METHODS: Thirteen boys with severe hemophilia (H) (mean (+/- SD) age = 12.0 +/- 3.17 yr) and 16 control (C) boys (age = 11.9 +/- 2.8 yr) performed elbow and knee flexion and extension on the Biodex System II dynamometer at two angular velocities. They also performed a Wingate Anaerobic Test (WAnT) for the legs and for the arms. All H subjects received prophylactic factor VIII treatment in the 24 h pretesting, and no test was performed in the presence of hemorrhage. RESULTS: C were consistently stronger than H in all dynamic strength measures (e.g., elbow flexors: 0.47 +/- 0.15 vs 0.36 +/- 0.08 N x m x kg(-1) for C and H, respectively, P < 0.05). Anaerobic mean power was also higher in C compared with H in both upper and lower extremities (arms: 3.08 +/- 0.99 vs 2.22 +/- 0.46 W x kg(-1) for C and H, respectively; legs: 6.94 +/- 1.62 vs 5.54 +/- 1.03 W x kg(-1) for C and H, respectively, P < 0.05). Upper and lower extremity strength, as well as anaerobic power, increased with age in C but not in H. By using the Godin Leisure-Time Exercise Questionnaire, H were found to be much less active, especially in intense activities, compared with C. CONCLUSION: Children and adolescents with hemophilia are characterized by lower muscle strength and anaerobic power compared with age-matched controls. This may be related to their lower leisure-time activity.     

Does upper body strength and power influence upper body Wingate performance in men and women?

The aim of this study was to determine the influence of muscular strength and power on upper body Wingate performance in men and women. Muscular strength (1 repetition maximum bench press), muscular power (bench throws) and upper body anaerobic performance (Wingate Anaerobic Test (WAnT)) was assessed in 24 men and 16 women. Men had significantly ( P<0.001) higher absolute and relative peak and mean power and blood lactate concentration during the WAnT compared to their female counterparts. Men also produced significantly ( P<0.001) higher strength and absolute and relative peak and mean power during the bench press and throw, respectively, compared to the female participants. For men body mass and mean power produced during the bench throw explained approximately 84% and 87% of the variance in Wingate peak ( P<0.001 and P=0.039, respectively) and mean ( P<0.001 and P=0.028, respectively) power. For women mean power produced during the bench throw explained approximately 72% and 52% of the variance in Wingate peak ( P=0.002) and mean ( P=0.017) power, respectively. For men body mass and to a lesser extent muscular power best predicts upper body Wingate performance while for women only muscular power predicts upper body Wingate performance.     

Anaerobic contribution during maximal anaerobic running test: correlation with maximal accumulated oxygen deficit

The aims of this study were: (i) to measure energy system contributions in maximal anaerobic running test (MART); and (ii) to verify any correlation between MART and maximal accumulated oxygen deficit (MAOD). Eleven members of the armed forces were recruited for this study. Participants performed MART and MAOD, both accomplished on a treadmill. MART consisted of intermittent exercise, 20 s effort with 100 s recovery, after each spell of effort exercise. Energy system contributions by MART were also determined by excess post-exercise oxygen consumption, lactate response, and oxygen uptake measurements. MAOD was determined by five submaximal intensities and one supramaximal intensity exercises corresponding to 120% at maximal oxygen uptake intensity. Energy system contributions were 65.4±1.1% to aerobic; 29.5±1.1% to anaerobic a-lactic; and 5.1±0.5% to anaerobic lactic system throughout the whole test, while only during effort periods the anaerobic contribution corresponded to 73.5±1.0%. Maximal power found in MART corresponded to 111.25±1.33 mL/kg/min but did not significantly correlate with MAOD (4.69±0.30 L and 70.85±4.73 mL/kg). We concluded that the anaerobic a-lactic system is the main energy system in MART efforts and this test did not significantly correlate to MAOD.     

Effects of kinesio taping on anaerobic power recovery after eccentric exercise

The aim of the study was to evaluate the effectiveness of kinesio taping (KT) in anaerobic power recovery after eccentric exercise. The study was carried out on 10 healthy men. The participants performed two 60-min downhill runs with a constant intensity. Peak anaerobic power (PP) and mean power (MP) were measured before and five times after eccentric exercise. Anaerobic power was evaluated with the Maximal Cycling Sprint Test. After the downhill run, passive recovery (PR) and KT (lymphatic application) were applied in random order. A significant decrease in PP and MP was observed at least for 24 h after PR, compared to baseline. After the KT application 24 h after eccentric exercises, anaerobic power was already similar to the baseline measurement. The application of KT significantly improved anaerobic power recovery time after eccentric exercise compared to the period of passive rest immediately prior to testing.     

11～18岁男女青少儿无氧功能的年龄和性别特征的研究

本文用目前国际上常采纳的Wingate无氧实验方法,对265名11～18岁的男女青少儿进行了无氧功能的测试。结果显示,在此年龄段,男性无氧功率的绝对值和相对值均随年龄增长,女性无氧功率的绝对值也随年龄增长,但相对值出现停滞现象。在13～18岁阶段,男性的无氧功率显著高于女性。     

No effect of moderate hypohydration or hyperthermia on anaerobic exercise performance

PURPOSE: This study examined the effects of hypohydration and moderate hyperthermia (core temperature elevation) on anaerobic exercise performance in a temperate environment. METHODS: Eight active males completed two passive heat exposure trials (180 min, 45 degrees C, 50% rh) with (EUH) and without (HYP) fluid replacement. A single 15-s Wingate anaerobic test (WAnT) was used to assess anaerobic performance (peak power, mean power, and fatigue index) before (-180 min) and again at three time points after passive heat exposure to include immediately (0 min), 30 min, and 60 min after in a temperate environment (22 degrees C). Rectal temperature (Tc) was measured throughout the experiment. RESULTS: HYP reduced body mass (2.7+/-0.7%) (P<0.05) but had no effect on any WAnT performance measure. Passive heat exposure elicited moderate hyperthermia in both trials (EUH: 0.6 degrees C; HYP: 1.0 degrees C) and returned to baseline within 30-60 min following similar decay curves. HYP Tc remained higher (0.4 degrees C) than EUH throughout testing (P<0.05), but moderate hyperthermia itself produced no independent effect on anaerobic exercise performance in either trial. CONCLUSIONS: This study demonstrates that neither moderate HYP nor the moderate hyperthermia accompanying HYP by passive heat exposure affect anaerobic exercise performance in a temperate environment.     

无氧功与肌电图MPF、IEMG

本文观察了44名男青少年运动员在1分钟无氧功实验中肌电图的变化,指出运动专项对无氧功下降有着明显影响,无氧功下降斜率可反映肌肉的抗疲劳能力。     

利用低氧帐篷进行"高住低练"对划船运动员运动能力影响的初探

目的探讨"高住低练"(运动员睡在相当于2500m的高度,训练则在平原)与"低住低练"对划船运动员运动能力影响的差别.通过对20名划船运动员的对比研究,发现运动员在进行为期4周的高住低练过程中,实验组在实验第15天、第30天,红细胞数、红细胞压积及血红蛋白水平均明显高于实验前水平,对照组则在上述时间段无明显变化.HiLo组运动员4mmol/L乳酸无氧阈功率明显高于实验前,比实验前平均增长了31W,对照组仅增长了10.5W,与实验前相比无明显差异,实验组的增长值明显高于对照组.两组运动员的无氧作功能力无明显差异.实验组和对照组2000m成绩与实验前比较,均无显著性差异,但实验组的平均成绩提高幅度要大于对照组;5000m成绩两组与实验前比较都有明显提高,但是实验组出现十分显著的提高,提高值显著高于对照组.以上结果表明,高住低练能明显提高运动员的有氧耐力和专项耐力成绩.     

A semi-tethered test for power assessment in running

We analyzed the usefulness of a semi-tethered field running test (STR) and the relationships between indices of anaerobic power, anaerobic capacity and running performance in 9 trained male sprinters (22.2 ± 2.9 yrs, 176 ± 1 cm, 68.0 ± 9.4 kg). STR involved an all out 120 m run attached to an apparatus that enabled power calculation from force and velocity measures. Subjects also carried out a cycloergometer Wingate Anaerobic Test (WT), an all out 300 m run and had accessed their maximal accumulated oxygen deficit (MAOD) on a treadmill. Peak and mean powers attained in STR (1720 ± 221 and 1391 ± 201 W) were greater but significantly related (r = 0.82; P < 0.01) to those in the WT (808 ± 130 and 603 ± 87 W). In addition, power measures derived from the STR were stronger related to running performance compared to those from the WT (r = 0.81-0.94 vs. 0.68-0.84; P < 0.05). Relationships between MAOD and most power indices were only weak to moderate. These results support the usefulness of STR for specific power assessment in field running and suggest that anaerobic power and capacity are not related entities, irrespective of having been evaluated using similar or dissimilar exercise modes.     

Maximal anaerobic power in Indian national hockey players.

Anaerobic power in relation to field position of 90 Indian hockey players has been studied. These players included 10 goalkeepers, 16 backs, 20 half-backs and 44 forwards. The goalkeepers possess maximum and forwards possess minimum anaerobic power while in vertical velocity, the former are the fastest and the latter are the slowest. In body weight the backs are heaviest followed by half-backs, goalkeepers and forwards. Among backs, the lefts are heavier, faster and have more anaerobic power than rights. In half-line players, the centre-half-backs are followed by left-half-backs and right-half-backs both in body weight and anaerobic power, while in vertical velocity, the left-half-backs are the fastest and centre-half-backs are the slowest. Among forwards, the centre-forwards are heaviest with maximum anaerobic power and are followed by inside-forwards and outside-forwards, whereas, in vertical velocity the inside-forwards are fastest followed by centre-forwards and outside-forwards.     

Assessing accuracy of measurements for a Wingate Test using the Taguchi method

The purpose of this study was to establish the effects of four variables on the results obtained for a Wingate Anaerobic Test (WAnT). This study used a 30 second WAnT and compared data collection and analysed in different ways in order to form conclusions as to the relative importance of the variables on the results. Data was collected simultaneously by a commercially available software correction system manufactured by Cranlea Ltd., (Birmingham, England) system and an alternative method of data collection which involves the direct measurement of the flywheel velocity and the brake force. Data was compared using a design of experiments technique, the Taguchi method. Four variables were examined - flywheel speed, braking force, moment of inertia of the flywheel, and time intervals over which the work and power were calculated. The choice of time interval was identified as the most influential variable on the results. While the other factors have an influence on the results, the decreased time interval over which the data is averaged gave 9.8% increase in work done, 40.75% increase in peak power and 13.1% increase in mean power.     

Locomotion in simulated microgravity: gravity replacement loads

BACKGROUND: When an astronaut walks or runs on a treadmill in microgravity, a subject load device (SLD) is used to return him or her back to the treadmill belt. The gravity replacement load (GRL) in the SLD is transferred, via a harness, to the pelvis and/or the shoulders. This research compared comfort and ground reaction forces during treadmill running in a microgravity locomotion simulator at GRLs of 60%, 80%, and 100% of body weight (BW). Two harness designs (shoulder springs only (SSO) and waist and shoulder springs (WSS)) were used. HYPOTHESES: 1) The 100% BW gravity replacement load conditions would be comfortably tolerated and would result in larger ground reaction forces and loading rates than the lower load conditions, and 2) the WSS harness would be more comfortable than the SSO harness. METHODS: Using the Penn State Zero Gravity Locomotion Simulator (ZLS), 8 subjects ran at 2.0 m x s(-1) (4.5 mph) for 3 min at each GRL setting in each harness. Subjective ratings of harness comfort, ground reaction forces, and GRL data were collected during the final minute of exercise. RESULTS: The 100% BW loading conditions were comfortably tolerated (2.3 on a scale of 0-10), although discomfort increased as the GRL increased. There were no overall differences in perceived comfort between the two harnesses. The loading rates (27.1, 33.8, 39.1 BW x s(-1)) and the magnitudes of the first (1.0, 1.4, 1.6 BW) and second (1.3, 1.7, 1.9 BW) peaks of the ground reaction force increased with increasing levels (60, 80, 100% BW respectively) of GRL. CONCLUSIONS: Subjects were able to tolerate a GRL of 100% BW well. The magnitude of the ground reaction force peaks and the loading rate is directly related to the magnitude of the GRL.     

Anticipatory pacing strategies during supramaximal exercise lasting longer than 30 s

PURPOSE: This study assessed whether pacing strategies are adopted during supramaximal exercise bouts lasting longer than 30 s. METHODS: Eight healthy males performed six Wingate anaerobic tests (WAnT). Subjects were informed that they were performing four 30-s WAnT, a 33-s, and a 36-s WAnT. However, they actually completed two trials of 30, 33, and 36 s each. Temporal feedback in the deception trials was manipulated so that subjects were unaware of the time discrepancy. Power output was determined from the angular displacement of the flywheel. The peak power (PPI), mean power (MPI), and fatigue (FI) indices were calculated for each trial. RESULTS: Power output was similar for all trials up to 30 s. However, at 36 s, the power output was significantly lower in the 36-s deception trial compared with the 36-s informed trial (392 +/- 32 W vs 470 +/- 88 W) (P < 0.001). The MPI was significantly lower in the 36-s trials (714 +/- 76 W and 713 +/- 78 W) compared with the 30-s trials (745 +/- 65 W and 764 +/- 82 W) although they were not different at 30 s (764 +/- 83 W and 755 +/- 79 W). The significant reduction in FI was greatest in the 36-s deception trial. CONCLUSIONS: The significant reduction in power output in the last 6 s of the 36-s deception trial, but not in the 36-s informed trial, indicates the presence of a preprogrammed 30-s "end point" based on the anticipated exercise duration from previous experience. The similarity in pacing strategy suggests that the pacing strategy is centrally regulated.