VO2 prediction and cardiorespiratory responses during underwater treadmill exercise

We compared cardiorespiratory responses to exercise on an underwater treadmill (UTM) and land treadmill (LTM) and derived an equation to estimate oxygen consumption (VO2) during UTM exercise. Fifty-five men and women completed one LTM and five UTM exercise sessions on separate days. The UTM sessions consisted of chest-deep immersion, with 0, 25, 50, 75, and 100% water-jet resistance. All session treadmill velocities increased every 3 min from 53.6 to 187.8 m x min(-1). Cardiorespiratory responses were similar between LTM and UTM when jet resistance for UTM was 50%. Using multiple regression analysis, weight-relative VO2 could be estimated as: VO2 (mLO2 c kg(-1) x min(-1)) = 0.19248 x height (cm) + 0.17422 x jet resistance (% max) + 0.14092 x velocity (m x min(-1)) -0.12794 x weight (kg)-27.82849, R2 = .82. Our data indicate that similar LTM and UTM cardiorespiratory responses are achievable, and we provide a reasonable estimate of UTM VO2.     

An objective method for depicting team performance in elite professional rugby union

Using a two-study approach, we examined a methodology for objectively depicting team performance and form in a professional rugby union side. Study 1 developed standardized indicators to examine a team's performance in a single match relative to their previous matches over a domestic season via a performance report and form chart. This resulted in standardized performance indicators that provided instant and coherent feedback on the team's performance relative to previous standards. Study 2 then utilized this methodology to compare a match between two professional sides, played the following season, to assess the extent to which the performance by one team affected that of the other. Comparison of the two teams' performances, for the match they played against each other, identified a drop in relative performance (against previous standards) for both teams on the same performance indicators. This appeared to be due to the match being a close, hard-fought contest particularly in the tackle and around the gain-line. The findings of the two studies suggest an accurate and viable methodology for depicting team performance that is superior to the global measures previously adopted. Presenting teams' current standardized performances (i.e. form) on a single visual scale also has utility for coaches within an applied setting. Future research should further investigate the effect of one team's performance on another through both individual and team outcomes.     

Hearts in the fire, heads in the fridge: a qualitative investigation into the temporal patterning of the precompetitive psychological response in elite performers

Retrospective perceptions and causal beliefs regarding the temporal patterning of precompetitive psychological responses were examined in 12 elite rugby union players. Composite sequence analysis resulted in a series of temporal networks to describe participants' cognitive, affective, and behavioural responses in a time-to-event paradigm. Match-related cognitions remained stable in the lead up to competition, while perceptions of physical symptoms peaked at the onset of performance. Affective responses were associated with feelings of anxiety and tension in the early temporal phases but excitement, confidence, and efficacy in team-mates directly before competition. Behavioural themes described activities associated with technical and physical preparation, familiarization with environmental conditions, and strategies to control activation states early on or directly before competition. The findings highlight the idiosyncratic and dynamic nature of the temporal patterning of precompetitive responses and the influence that perceptions of the team have upon individual preparation for performance. Implications are discussed in the context of the type and timing of intervention for developing individual and team preparatory routines.     

Relationship between maximal oxygen uptake and oxygen uptake attained during treadmill middle-distance running

Traditionally, it has been assumed that during middle-distance running oxygen uptake (VO2) reaches its maximal value (VO2max) providing the event is of a sufficient duration; however, this assumption is largely based on observations in individuals with a relatively low VO2max. The aim of this study was to determine whether VO2max is related to the VO2 attained (i.e. VO2peak) during middle-distance running on a treadmill. Fifteen well-trained male runners (age 23.3 +/- 3.8 years, height 1.80 +/- 0.10 m, body mass 76.9 +/- 10.6 kg) volunteered to participate in the study. The participants undertook two 800-m trials to examine the reproducibility of the VO2 response. These two trials, together with a progressive test to determine VO2max, were completed in a randomized order. Oxygen uptake was determined throughout each test using 15-s Douglas bag collections. Following the application of a 30-s rolling average, the highest VO2 during the progressive test (i.e. VO2max) was compared with the highest VO2 during the 800-m trials (i.e. VO2peak) to examine the relationship between VO2max and the VO2 attained in the 800-m trials. For the 15 runners, VO2max was 58.9 +/- 7.1 ml x kg(-1) x min(-1). Two groups were formed using a median split based on VO2max. For the high and low VO2max groups, VO2max was 65.7 +/- 3.0 and 52.4 +/- 1.8 ml x kg(-1) x min(-1) respectively. The limits of agreement (95%) for test-retest reproducibility for the VO2 attained during the 800-m trials were +/- 3.5 ml x kg(-1) x min(-1) for a VO2peak of 50.6 ml x kg(-1) x min(-1) (the mean VO2peak for the low VO2max group) and +/- 2.3 ml x kg(-1) x min(-1) for a VO2peak of 59.0 ml x kg(-1) x min(-1) (the mean VO2peak for the high VO2max group), with a bias in VO2peak between the 800-m runs (i.e. the mean difference) of 1.2 ml x kg(-1) x min(-1). The VO2peak for the 800-m runs was 54.8 +/- 4.9 ml x kg(-1) x min(-1) for all 15 runners. For the high and low VO2max groups, VO2peak was 59.0 +/- 3.3 ml x kg(-1) x min(-1) (i.e. 90% VO2max) and 50.6 +/- 2.0 ml x kg(-1) x min(-1) (i.e. 97% VO2max) respectively. The negative relationship (-0.77) between VO2max and % VO2max attained for all 15 runners was significant (P = 0.001). These results demonstrate that (i) reproducibility is good and (ii) that VO2max is related to the %VO2max achieved, with participants with a higher VO2max achieving a lower %VO2max in an 800-m trial on a treadmill.     

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.     

Metaphor use and perceived managerial effectiveness

This study examines the metaphorical language of three managers in a Northwest city government. Four communication specialists used an interpretative method to identify, categorize, and rate perceptions of metaphors in three 30‐minute transcribed interviews. The results establish a set of metaphor categories, support a theory of culturally‐shared metaphors, demonstrate managers' differences in metaphor use, and suggest an association between managers metaphor use and subordinate ratings of effectiveness.