Manchester Metropolitan University

About: Manchester Metropolitan University is a education organization based out in Manchester, Manchester, United Kingdom. It is known for research contribution in the topics: Population & Context (language use). The organization has 5435 authors who have published 16202 publications receiving 442561 citations. The organization is also known as: Manchester Polytechnic & MMU.

Influence of continuous and interval training on oxygen uptake on-kinetics.

Abstract: Purpose To examine the relative effectiveness of moderate-intensity continuous training and high-intensity interval training on pulmonary O2 uptake (VO2) kinetics at the onset of moderate- and severe-intensity cycle exercise in previously sedentary subjects. Methods Twenty-three healthy subjects (11 males; mean +/- SD age 24 +/- 5 yr; VO2peak 34.3 +/- 5.5 mL x kg(-1) x min(-1)) were assigned to one of three groups: a continuous training group that completed three to four sessions per week of 30-min duration at 60% VO2peak (LO); an interval training group that completed three to four sessions per week involving 20 x 1-min exercise bouts at 90% VO2peak separated by 1-min rest periods (HI); or a control group (CON). Before and after the 6-wk intervention period, all subjects completed a series of step exercise tests to moderate and severe work rates during which pulmonary VO2 was measured breath-by-breath. Results ANOVA revealed that continuous and interval training were similarly effective in reducing the phase II VO2 time constant during moderate (LO: from 31 +/- 8 to 23 +/- 5 s; HI: from 32 +/- 9 to 21 +/- 4 s; both P Conclusions Six weeks of low-intensity continuous training and high-intensity interval training were similarly effective in enhancing VO2 on-kinetics following step transitions to moderate and severe exercise in previously untrained subjects.

Effects of prior exercise and recovery duration on oxygen uptake kinetics during heavy exercise in humans.

Abstract: Prior heavy exercise (above the lactate threshold, LT) reduces the amplitude of the pulmonary oxygen uptake (VO2) slow component during heavy exercise, yet the precise effect of prior heavy exercise on the phase II VO2 response remains to be established. This study was designed to test the hypotheses that (1) prior heavy exercise increases the amplitude of the phase II VO2 response independently of changes in the baseline VO2 value and (2) the effect of prior exercise depends on the amount of external work done during prior exercise, irrespective of the intensity of the prior exercise. Nine subjects performed two 6 min bouts of heavy cycling exercise separated by 6 min baseline pedalling recovery (A), two 6 min heavy exercise bouts separated by 12 min recovery (6 min rest and 6 min baseline pedalling, B), and a bout of moderate exercise (below the LT) in which the same amount of external work was performed as during the prior heavy exercise, followed by 6 min heavy exercise (C). In both tests A and B, prior heavy exercise significantly increased the absolute VO2 amplitude at the end of phase II (by approximately 150 ml x min(-1)), and reduced the amplitude of the VO2 slow component by a similar amount. Following 12 min of recovery (B), baseline VO2, but not blood [lactate], had returned to pre-exercise levels, indicating that these effects occurred independently of changes in baseline VO2. Prior moderate exercise (C) had no effect on either the VO2 or blood [lactate] responses to subsequent heavy exercise. The VO2 response to heavy exercise was therefore dependent on the intensity of prior exercise, and the effects on the amplitudes of the phase II and slow VO2 components persisted for at least 12 min following prior heavy exercise.

Retention of oral microorganisms on cobalt-chromium alloy and dental acrylic resin with different surface finishes.

Abstract: STATEMENT OF PROBLEM: The effect of surface finish of dental materials on the subsequent contamination by microorganisms. PURPOSE: This study compared the retention of Streptococcus oralis, Actinomyces viscosus, and Candida albicans on polished, sandblasted (fine and coarse) and electrobrightened cobalt-chromium alloy and dental acrylic resin to assess in vitro the effect of such techniques on prosthesis contamination. MATERIAL AND METHODS: Standardized cell suspensions were incubated with test materials for 1 hour at 37 degrees C, after which retained cells were counted by using image analysis (percentage area of a microscopic field covered by cells). RESULTS: Retention of bacterial cells was substantial (S oralis 12% to 20% and A viscosus 9% to 16%) irrespective of surface finish. Maximal retention was observed on cobalt-chromium alloy that had undergone fine sandblasting and electrobrightening (P < .01). For C albicans, an increase in surface roughness (0.15 to 3.53 microns) resulted in an increase in retention (3% to 9%). CONCLUSION: Cell size and the type of roughening significantly affected the retention of microorganisms on surfaces. Electrobrightening of cobalt-chromium alloy did not reduce the surface roughness or subsequent cell attachment.