The influence of crank rate on peak oxygen consumption during arm crank ergometry

The aim of this study was to assess the influence of three imposed crank rates on the attainment of peak oxygen consumption ( V O 2peak ) and other physiological responses during incremental arm crank ergometry. Twenty physically active, although non-specifically trained, males volunteered for the study. They completed an exercise protocol using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands) at crank rates of 60, 70 and 80 rev·min -1 . The order of tests was randomized and they were separated by at least 2 days. Peak V O 2 was significantly higher ( P ? 0.05) at 70 and 80 rev·min -1 than at 60 rev·min -1 . Peak ventilation volume increased as a function of crank rate and was higher ( P ? 0.05) at 80 than at 60 rev·min -1 . Peak heart rate was higher ( P ? 0.05) at 70 and 80 rev·min -1 than at 60 rev·min -1 . Furthermore, 70 and 80 rev·min -1 resulted in an extended test time compared with 60 rev·min -1 . The greater physiological responses observed during the tests at the two faster crank rates might have been the result of a postponement of acute localized neuromuscular fatigue, allowing for more work to be completed. We recommend, therefore, that an imposed crank rate between 70 and 80 rev·min -1 should be used to elicit V O 2peak and other physiological responses in arm crank ergometry.     

Effect of 6 weeks of endurance training on the lactate minimum speed

The aim of this study was to assess the sensitivity of the lactate minimum speed test to changes in endurance fitness resulting from a 6 week training intervention. Sixteen participants (mean +/- s :age 23 +/- 4 years;body mass 69.7 +/- 9.1 kg) completed 6 weeks of endurance training. Another eight participants (age 23 +/- 4 years; body mass 72.7 +/-12.5 kg) acted as non-training controls. Before and after the training intervention, all participants completed: (1) a standard multi-stage treadmill test for the assessment of VO 2max , running speed at the lactate threshold and running speed at a reference blood lactate concentration of 3 mmol.l -1 ; and (2) the lactate minimum speed test, which involved two supramaximal exercise bouts and an 8 min walking recovery period to increase blood lactate concentration before the completion of an incremental treadmill test. Additionally, a subgroup of eight participants from the training intervention completed a series of constant-speed runs for determination of running speed at the maximal lactate steady state. The test protocols were identical before and after the 6 week intervention. The control group showed no significant changes in VO 2max , running speed at the lactate threshold, running speed at a blood lactate concentration of 3 mmol.l -1 or the lactate minimum speed.In the training group, there was a significant increase in VO 2max (from 47.9 +/- 8.4 to 52.2 +/- 2.7 ml.kg -1 .min -1 ), running speed at the maximal lactate steady state (from 13.3 +/- 1.7 to 13.9 +/- 1.6 km.h -1 ), running speed at the lactate threshold (from 11.2 +/- 1.8 to 11.9 +/- 1.8 km.h -1 ) and running speed at a blood lactate concentration of 3 mmol.l -1 (from 12.5 +/- 2.2 to 13.2 +/- 2.1 km.h -1 ) (all P ? 0.05). Despite these clear improvements in aerobic fitness, there was no significant difference in lactate minimum speed after the training intervention (from 11.0 +/- 0.7 to 10.9 +/- 1.7 km.h -1 ). The results demonstrate that the lactate minimum speed,when assessed using the same exercise protocol before and after 6 weeks of aerobic exercise training, is not sensitive to changes in endurance capacity.     

Development and initial validation of an instrument to assess the motivational qualities of music in exercise and sport: The Brunel Music Rating Inventory

Equivocal results of the psychophysical effects of music have been explained in part by the insensitivity of researchers to important personal and situational variables when selecting music. The aim of the present study was to operationalize a conceptual framework for the prediction of psychophysical responses to music into a music rating inventory to assess the motivational qualities of music in exercise and sport environments. An initial item pool was developed and administered to 334 aerobics instructors. Exploratory factor analysis produced a 13-item, four-factor structure (association, musicality, cultural impact and rhythm response), which accounted for 59.2% of the variance. This model demonstrated acceptable fit indices when tested using confirmatory factor analysis on 314 exercise-to-music participants, and was better than an alternative two-factor model. When cross-validated using multisample confirmatory factor analysis, the model also showed an acceptable fit overall, although some invariance in the rhythm response factor was evident that can be attributed to the exclusive use of synchronous music by aerobics instructors. The Brunel Music Rating Inventory appears to be a valid and reliable tool for both researchers and practitioners to assess the motivational qualities of music in exercise and sport environments.     

A modified incremental shuttle run test for the determination of peak shuttle running speed and the prediction of maximal oxygen uptake

The aim of this study was to determine the incidence of subject drop-out on a multi-stage shuttle run test and a modified incremental shuttle run test in which speed was increased by 0.014m.s-1 every 20-m shuttle to avoid the need for verbal speed cues. Analysis of the multi-stage shuttle run test with 208 elite female netball players and 381 elite male lacrosse players found that 13 (+/-3) players stopped after the first shuttle of each new level, in comparison with 5 (+/-2) players on any other shuttle. No obvious drop-out pattern was observed on the incremental shuttle run test with 273 male and 79 female undergraduate students. The mean difference between a test-retest condition (n= 20) for peak shuttle running speed (-0.03+/- 0.01m.s-1) and maximal heart rate (0.4+/- 0.1 beats.min-1) on the incremental test showed no bias (P > 0.05). The 95% absolute confidence limits of agreement were 0.11m.s-1 for peak shuttle running speed and +/-5 beats.min-1 for maximal heart rate. The relationship (n= 27) between peak shuttle running speed on the incremental shuttle run test (4.22+/- 0.14m.s-1) and VO2max (59.0+/- 1.7ml.kg-1.min-1) was r=0.91 (P< 0.01), with a standard error of prediction of 2.6ml.kg-1.min-1. These results suggest verbal cues during the multi-stage shuttle run test may influence subject drop-out. The incremental shuttle run test shows no obvious drop-out patten and provides a valid estimate of VO2max.     

The Arousal-Performance Relationship Revisited

Abstract

William P. Morgan reviews the arguments associated with trait psychology, in particular in the field of sport psychology. He describes the existing research including several models and their ability to predict behavior, emphasizing the viability of a mental health model. In addition, Morgan discusses a role of perception and cognition in sports and physical activity. Finally, trait theory is placed in a realistic perspective, to be applied in a multidimensional framework in studying prediction of behavior. The article by Daniel M. Landers involves a reexamination of the arousal-performance relationship. The role of attention in performing most sports skills is discussed, with particular emphasis on the attentional narrowing phenomenon. In addition, Landers discusses the measurement of anxiety, recommending that it be viewed as a multidimensional construct consisting of physical, behavioral, and cognitive components.     

Properties of Isokinetic Fatigue at Various Movement Speeds in Adult Males

Abstract

Eighteen male subjects, ages 20–28 years, engaged in three fatigue bouts using an isokinetic dynamometer (Cybex II). Maximum knee extension contractions were given for 100 s at a rate of 30 per minute. The three contraction speeds chosen were 120° · s ^–1 160° · s ^–1 and 200° · s ^–1.Peak torque at 120° · s ^–1 was significantly greater (p <.05) than at 200° · s ^–1 for the first 60 s, and 160° · s ^–1 for the first 50 s. Thereafter, no significant differences existed among conditions. All three curves were found to follow two-component exponential functions as shown by the equation y_t =a ₂ e^k2^t – a ₁ e^k1^t + c. The three curves possessed similar rate constants for both components. Time to peak torque was achieved at similar times for testing at 160 and 200° · s ^–1 (p <.05). It is concluded that peak torque varies inversely with movement speed, and that the pattern of decrement is independent of movement speed. Time to peak torque does not appear to change significantly across trials in isokinetic fatigue.     

Muscle Soreness Following Resistance Exercise With and Without Eccentric Contractions

The present study reported on translating the Exercise Identity Scale (EIS: Anderson &; Cychosz, 1994) into Greek and examining its psychometric properties and cross-cultural validity based on U.S. individuals' EIS responses. Using four samples comprising 33, 103, and 647 Greek individuals, including exercisers and nonexercisers, and a similar sample comprising 800 U.S. individuals, the concurrent validity, factor structure, internal reliability, test-retest reliability, external validity, gender invariance, and cross-cultural validity of the EIS responses were examined using confirmatory factor analytical procedures. The results supported the concurrent validity, an adequate unidimensional factor structure for the translated EIS and the internal reliability and test-retest reliability over a 6-week interval. Further, cross-gender configural, partial metric, partial strong factorial, and partial strict factorial invariance and cross-cultural configural and partial metric invariance supported the cross-cultural equivalence of the EIS versions. Moreover, the external validity of the translated EIS responses was also supported. Overall, the findings supported the validity of the exercise identity construct outside North American boundaries and the EIS items' equivalence, providing initial evidence for its cross-cultural applicability.     

Differential Effects of Three Teachers Over a Unit of Instruction

The purpose of this study was to describe the effects of three teachers on psychomotor, affective, and cognitive outcomes over a 15-lesson volleyball unit. Three intact middle school physical education classes were used. Pre- and posttests were administered for the overhead set, forearm pass, and serve psychomotor skills. A semantic differential test with four affective dimensions and a written test on the rules, strategies, and mechanics of volleyball were also administered pre- and posttest. Data on instructional characteristics were obtained using academic learning time (ALT-PE); observation system for content development (OSCD-PE), and a content analysis of lessons.

The following were key aspects of the results: (a) Teachers differed in their approaches to the content of the unit more than in the characteristics of their instruction as determined through observational data; (b) teachers differed in respect to the psychomotor skills for which they were able to produce statistically significant student gain; (c) the skill level of students played a major role in psychomotor outcomes; (d) affective measures started high and remained high from pre- to posttest with significant change occurring positively with the low-skilled in one measure; (d) cognitive learning was significant from pre- to posttest in rules and mechanics but not in strategies. Instructional characteristics, as described in this study, did not change from skill to skill, but student learning did. This led the authors to conclude that the instrumentation for instructional variables was not sensitive to differences in the way individual skills were handled by individual teachers.     

Epistemology and the Use of the .05 Level of Significance: A Rebuttal to Inductionism

In the first part of this study, the football potential of 67 football players was predicted from their scores on a football-potential test. The test battery consisted of motor ability items as well as football skill items. Substantial correlations were obtained between most test items and the test criterion, the sum of T scores. Size, as depicted by McCloy's classification index (C.I.), had a negative, nonsignificant correlation with the criterion. The discriminative power of the battery was evidenced by the highly significant correlation between the test criterion and the coaching staff's ranking of individual players (rho = .840). It was concluded that athletic potential in football can be predicted by testing. In the second part of the study, football teams from three different strata of competition were evaluated on the basis of the test battery. The battery substantiated a step-wise progression between the teams on most items, with significant differences being noted. The test showed validity, in that the test criterion (the sum of T scores) was significantly different between the teams.     

Gold Medal Volleyball: The Training Program and Physiological Profile of the 1984 Olympic Champions

Abstract

This study focused on the differences between experienced and inexperienced physical education teachers' approaches to planning, low inference indicators of teaching behavior during instruction, and global variables from the Beginning Teacher Evaluation Study. It was found experienced teachers asked many more questions before they began planning than did inexperienced teachers. Experienced teachers' plans reflected a concern about contingencies that might arise during instruction, whereas inexperienced teachers' plans did not. Interaction analysis and codings of student engagement showed marked differences between experienced and inexperienced teachers. Judging the qualities of experienced and inexperienced teachers also showed important differences. These sources of data are interrelated and give a vivid picture of how experienced and inexperienced teachers differ in accomplishment of instruction. The findings are discussed in terms of what they may mean for teacher development programs.