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A Casey

Publications and source records attributed to A Casey.

At least 55 records · Page 3Linked to original sources
PubMed1998

Transfer effects across contextual and linguistic boundaries: evidence from poor readers.

We report two experiments that are consistent with two hypotheses about poor, nonfluent readers: (1) fluency gains in text reading skill transfer across contextual and linguistic boundaries and (2) these fluency gains enable higher-order comprehension operations to function in the processing of text. We conclude that unlike the fluent reader, the nonfluent reader does not completely integrate the surface characteristics (words) of the text and the message of the text. Word-level representations remain free to support transfer across various processing episodes. Thus, a variety of reading experiences aimed at promoting word recognition fluency will provide benefits to the developing reader.

Analysis of Variance↗
PubMed1998

Stimulatory effect of insulin on creatine accumulation in human skeletal muscle.

This study investigated the effect of insulin on plasma and muscle creatine accumulation and limb blood flow in humans after creatine administration. Seven men underwent a 300-min euglycemic insulin clamp combined with creatine administration on four separate occasions. Insulin was infused at rates of 5, 30, 55, or 105 mU. m-2. min-1, and on each occasion 12.4 g creatine was administered. During infusion of insulin at rates of 55 and 105 mU. m-2. min-1, muscle total creatine concentration increased by 4.5 +/- 1.4 (P < 0. 05) and 8.3 +/- 1.0 mmol/kg dry mass (P < 0.05), and plasma creatine concentrations were lower at specific time points compared with the 5 mU. m-2. min-1 infusion rate. The magnitude of increase in calf blood flow (plethysmography) was the same irrespective of the rate of insulin infusion, and forearm blood flow increased to the same extent as the three highest infusion rates. These findings demonstrate that insulin can enhance muscle creatine accumulation in humans but only when present at physiologically high or supraphysiological concentrations. This response is likely to be the result of an insulin-mediated increase in muscle creatine transport rather than creatine delivery.

Adult↗
PubMed1998

Global concerns.

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Australia↗
PubMed1996

The effect of repeated muscle biopsy sampling on ATP and glycogen resynthesis following exercise in man.

The present study investigated the effect of repeated biopsy sampling on muscle adenosine 5'-triphosphate (ATP) and glycogen resynthesis following prolonged submaximal exercise. In one group of subjects (Ia, n = 7), biopsy specimens were obtained from the vastus lateralis immediately and 48 h after exhaustive one-legged cycling from both the non-exercised (control) and exercised legs. Additional samples were obtained from the exercised leg at 3, 10 and 24 h post-exercise. In a second group of subjects (Ib, n = 6), biopsy specimens were obtained immediately after exercise from both the control and exercised legs and at 48 h post-exercise from the exercised leg. All muscle biopsies were separated by a distance of 2.5 cm. In group Ia, ATP in the exercised leg was still lower after 48 h of recovery compared with the control leg (P <0.05), but complete restoration had occurred in group Ib (P > 0.05). Glycogen super compensation was not observed in group Ia. However, at the end of recovery, in group Ib glycogen in the exercised leg was 42 percent greater than in the control leg (P <0.01). Thus, following exhaustive dynamic exercise, repeated muscle biopsy sampling impaired ATP and glycogen resynthesis for several days, which may have been a result of the distance separating each biopsy site. The inhibition of ATP resynthesis appeared to be associated mainly with type II muscle fibres. The finding that, in contrast to muscle glycogen, ATP did not return to the basal level during the 48 h of recovery, suggests that the measurement of ATP may be a more sensitive measure of muscle damage than that of glycogen.

Adenosine Triphosphate↗
PubMed1996

The effect of glycogen availability on power output and the metabolic response to repeated bouts of maximal, isokinetic exercise in man.

The relationship of glycogen availability to performance and blood metabolite accumulation during repeated bouts of maximal exercise was examined in 11 healthy males. Subjects performed four bouts of 30 s maximal, isokinetic cycling exercise at 100 rev.min-1, each bout being separated by 4 min of recovery. Four days later, all subjects cycled intermittently to exhaustion [mean (SEM) 106 (6) min] at 75% maximum oxygen uptake (VO2max). Subjects were then randomly assigned to an isoenergetic low-carbohydrate (CHO) diet [7.8 (0.6)% total energy intake, n = 6] or an isoenergetic high-CHO diet [81.5 (0.4)%, n = 5], for 3 days. On the following day, all subjects performed 30 min cycling at 75% VO2max and, after an interval of 2 h, repeated the four bouts of 30 s maximal exercise. No difference was seen when comparing total work production during each bout of exercise before and after a high-CHO diet. After a low-CHO diet, total work decreased from 449 (20) to 408 (31) J.kg-1 body mass in bout 1 (P < 0.05), from 372 (15) to 340 (18) J.kg-1 body mass in bout 2 (P < 0.05), and from 319 (12) to 306 (16) J.kg-1 body mass in bout 3 (P < 0.05), but was unchanged in bout 4. Blood lactate and plasma ammonia accumulation during maximal exercise was lower after a low-CHO diet (P < 0.001), but unchanged after a high-CHO diet. In conclusion, muscle glycogen depletion impaired performance during the initial three, but not a fourth bout of maximal, isokinetic cycling exercise. Irrespective of glycogen availability, prolonged submaximal exercise appeared to have no direct effect on subsequent maximal exercise performance.

Adult↗