Effect of Toe Clips during Bicycle Ergometry on [Vdot]O2 max

Abstract

Previous investigators have yielded conflicting results in testing the hypothesis that the use of toe clips during bicycle ergometry produces a higher maximal oxygen uptake ([Vdot]O ₂ max) than testing without toe clips. Eight men, four competitive cyclists and four competitive distance runners volunteered to participate in three randomized [Vdot]O ₂ max tests: 1) a treadmill running lest, 2) a bicycle ergometer test using standard toe clips, and 3) a test on the same ergometer without toe clips. The highest mean [Vdot]O ₂ max was observed in the treadmill condition as expected. However, no statistically significant difference in mean [Vdot]O ₂ max or performance time was observed between the toe-clip and no toe-clip conditions. Based on these results, the research hypothesis was rejected and no favorable physiological effect may be attributed to the use of toe clips.     

Effect of Caffeine Ingestion on Cardiorespiratory Endurance in Men and Women

Abstract

The effect of caffeine ingestion on submaximal endurance performance of 15 females and 13 males was investigated. After completing a [Vdot]O ₂ max test, each subject performed two submaximal cycling tests at approximately 75% of [Vdot]O ₂ max to exhaustion. For the caffeine (C) trials, 300 mg of caffeine was added to 250 ml of decaffeinated coffee and ingested one hour prior to the exercise. The decaffeinated (D) trial involved consuming 250 ml of decaffeinated coffee an hour prior to the test. The C and D trials were administered randomly using a standard double blind design. Physiological parameters were monitored each 9, 10, and 11 minute intervals throughout each trial and averaged. As expected the [Vdot]O ₂ (L · min ^?1 ), [Vdot]E and work outputs (kgm) were significantly (p < 0.001) higher for the males than the females. All other variables, time to exhaustion, [Vdot]O ₂ (ml · kg · min ^?1 ), R, HR, and rating of perceived exertion (RPE) were not significantly (p > 0.05) different between the sexes for either the C or D trials. Time to exhaustion was 14.4 and 3.1% longer for the C trials for the females and males, respectively, however these increases were not significant (p > 0.05). Furthermore, there were no significant differences (p > 0.05) for any of the measured variables during successive 10 minute work intervals between the C and D trials for either sex. These results do not support the general use of caffeine in moderate amounts as an ergogenic aid for either males or females, but from a practical point it appears that caffeine may have an ergogenic effect on specific individuals.     

Alterations in Strength and Maximal Oxygen Uptake Consequent to Nautilus Circuit Weight Training

Abstract

The purpose of this study was to determine the effects of a Nautilus circuit weight training program on muscular strength and maximal oxygen uptake ([Vdot]O ₂ max) by comparing these effects to those produced by adhering to either a free weight (FW) strength training program or a running (R) program. Male college students who voluntarily enrolled in either a FW training class (n = 11), a Nautilus (N) circuit weight training class (n= 12), or a R conditioning class (n= 13) were subjects for this investigation. All groups participated in their respective programs 3 days per week for 10 weeks. Strength was assessed using a Cybex II isokinetic dynamometer set at an angular velocity of 60° · s ^?1 and a damping of 2. The FW group served as the control group for the assessment of [Vdot]O ₂ max changes, while the R group served as controls for the assessment of strength differences. ANCOVA revealed that the N and R groups experienced significant (p < .01) increases in [Vdot]O ₂ max expressed in L · min ^?1 (10.9 and 11.4%), ml · kg ^?1 · min ^?1 (10.8 and 11.7%), and ml · kgLBW ^?1 · min ^?1 (7.1 and 7.5%) when compared to the FW group. There were no significant differences between the N and R groups. There were no significant differences among groups in final peak torque values (after covariance), and torque at the beginning and end of the range of motion for the knee extensors, knee flexors, elbow extensors, and elbow flexors. In general, isokinetic strength values elicited by the N group compared favorably to those generated by the FW group. It was concluded that for a training period of short duration, Nautilus circuit weight training appears to be an equally effective alternative to standard free weight (strength) and aerobic (endurance) training programs for untrained individuals.     

Validity of Palpation Recovery Pulse Rate to Estimate Exercise Heart Rate Following Four Intensities of Bench Step Exercise

Abstract

Previous investigations regarding activity during the post-knowledge of results (KR) interval have considered the performance of interference groups over KR-supplied acquisition trials as indicative of effects upon learning. The absence of transfer tests in these studies, however, preclude such an assumption. Indeed, the use of a retention test in the present investigation (no-KR trials following an interpolated phase) provided evidence suggesting that, while activity during the post-KR interval is detrimental to performance, no such assumption can be made regarding this effect upon learning. These findings are discussed relative to recent arguments that some of the commonly accepted “Laws of KR” may be contradictory when applied simultaneously to motor learning and performance.     

Physical Performance Tests in Job Selection a Model for Empirical Validation

Abstract

The aim of this study was to establish the net energy cost of dribbling a soccer ball. Eight male footballers ran for 5 min on a treadmill at speeds of 9, 10.5, 12 and 13.5km ·h ^–1 while dribbling a football against a rebound box; running at each of these speeds without the ball constituted controls. Oxygen uptake ([Vdot]O ₂ ), perceived exertion (RPE) and blood lactate levels were measured and compared between the two conditions. The energy expended increased linearly with speed for both exercise modes, the mean increment of 1.24 kcal·min ^–1 caused by dribbling being independent of the speed of motion. Individual differences in efficiency of dribbling could not be explained by considering different patterns of stride characteristics. Similarly, RPE showed a constant elevation for dribbling over running at each speed, and a linear increase with speed of motion for both modes. Blood lactate increased disproportionately with speed for dribbling, onset of metabolic acidosis being attained at a lower speed for the experimental task. It was concluded that dribbling a ball does significantly increase the energy cost and perceived exertion of motion, as well as inducing disproportionate rises in blood lactate when performed at high speeds.     

等摩尔连续变化法测定瓜环包结配合物的包结比

讨论了等摩尔连续变化法测定瓜环包结配合物包结比的理论依据,并利用紫外吸收光谱和荧光光谱测定了七、八元瓜环(Q [7],Q[8])与α-萘胺(q1)、β-萘胺(q1)两种异物体相互作用形成包结配合物的包结比。实验结果表明:等摩尔连续变化法较摩尔比法结果更清晰、更准确。七元瓜环与两种萘胺异构体只能形成1:1的包结,八元瓜环与苯胺两种异构体则形成1:2的包结。     

正交表Ltu[tq]的构造及正交性的证明

不同类型正交表的构造差异很大，本文从实用的角度来研究Lt^u[t^q]型正交表的构造，并对其正交性进行证明。     

孟府档案中的珍品——敕命文书

孟府档案中的敕命文书是清王朝颁给孟府主人的重要文书,也是孟府档案中的珍品,现存山东省邹城市博物馆14件。它是孟氏家族在清王朝时期家族地位状况的真实记录,是研究孟子及其家族的第一手史料,也是珍贵的文物。同时,也是我们研究清代社会状况和文书体式的标本。     

“War Through Children’s Eyes” in the Archiwum Wschodnie [Eastern Archive] Collection

In 1981, Hoover Institution Press published a collection of testimonies of Polish citizens and their children deported to the Soviet Union between 1939 and 1941. War Through Children’s Eyes contained English translations of compositions, interviews, and testimonies from the Polish Government Collection at the Hoover Institution Archives. In the 1980s efforts were underway in Poland to collect similar personal stories of survivors of Soviet deportations, including children’s testimonies. The result was the creation of the Archiwum Wschodnie [Eastern Archive] and the KARTA Center in Warsaw. The archive, legalized after the fall of Communism in 1990, is a major primary source collection dealing with the history of former Polish eastern territories. The paper discusses parts of the Archiwum Wschodnie collection focusing on the testimonies of children deported to the Soviet Union. The trauma of war and displacement is examined through personal stories and testimonies of deportees.     

河蚬蛋白酶法水解工艺的研究

以河蚬为原料,水解度和氮收率为指标,筛选出适合河蚬酶解的蛋白酶,利用二次回归正交旋转组合试验建立水解度与加酶量、酶解温度、酶解时间的数学回归模型,确定河蚬蛋白酶法水解的最佳工艺条件为：液固比3：1,混合酶（Neutrase／Alcalase）组合比例3：1,pH值7．O,加酶量1．3％。酶解温度53℃,酶解时间261rain,此时水解度为46．1％,氮收率81．2％．