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To evaluate the effects of short-term physical training on muscle fibre size, seven males were submitted to an eight-week swimming programme. Biopsy samples from the triceps brachii muscle were obtained before and after the training period, and compared with controls. After training, free swimming maximal oxygen uptake was significantly higher in the exercise subject (3.61 to 3.76 l x min-1), whereas the type I fibre distribution in the triceps was not affected (45.5 vs 44.6%). However, a significant increase in type II fibre area was observed (23.8%) and the type II/type I fibre area ratio increased from 1.63 to 1.83 with training. Muscle succinate dehydrogenase and phosphofructokinase activities were not significantly affected by the training programme. No significant changes were observed in the control group. It is concluded that type II fibres are recruited preferentially during a short-term swim-training programme...

Myosin was isolated from heart ventricle, soleus and gastrocnemius of freshly slaughtered swine. ATPase activities (mu moles Pi/mg/min) were found to be higher in heart muscle (Ca++ activated = .39 +/- .04; EDTA activated = .59 +/- .06) than in ST soleus (Ca++ activated = .23 +/- .02; EDTA activated = .48 +/- .05) or FT gastrocnemius (Ca++ activated = .32 +/- .03; EDTA activated = .52 +/- .04). The results suggest that the myosin of swine cardiac muscle is different from the myosin of skeletal muscle, or at least, the rate of hydrolysis of ATP on the myosin sites is different between these tissues. There is a difference in relationship of ATPase between heart and skeletal muscle in swine compared to that seen in other mammalian species.

The effects of beta-blockade on muscle utilization of glycogen and triglycerides, as well as potassium metabolism, were studied in eight healthy male subjects performing long-duration exercise to exhaustion. Subjects were studied after treatment with either placebo (PLAC), beta 1-selective (atenolol, 100 mg/day, AT), or nonselective beta-blockade (nadolol, 80 mg/day, NAD) each for 1 wk according to a randomized, double-blind, cross-over design. NAD and AT caused identical decreases in exercise heart rates, but endurance (71 +/- 8 min with PLAC) decreased significantly more with NAD (-33 +/- 4%) than with AT (-14 +/- 6%). Muscle glycogen breakdown, taking exercise time into account, was unaffected by treatment. In contrast, muscle triglyceride utilization was completely blocked by NAD whereas it was unchanged with AT as compared to PLAC. Adipose tissue lipolysis was inhibited to a similar extent by the two beta-blockers. Serum potassium increased to higher levels at exhaustion and muscle potassium decreased to lower levels with NAD than with AT or PLAC. These results suggest that decreased utilization of muscle triglycerides combined with lack of an enhanced glycogenolysis to compensate as well as alterations in potassium metabolism contribute to the decreased exercise capacity with nonselective beta-blockade compared with beta 1-selective blockade.

The influence on the antibacterial activity of introducing a 6 alpha-methoxy group into carbenicillin, and various 6 alpha-substituents into sulbenicillin and piperacillin was examined. Further variations of the side chain aryl group were examined in the 6 alpha-methoxy substituted series. This led to the identification of disodium 6 beta-(D,L-2-carboxy-2-thien-3-ylacetamido)-6 alpha-methoxypenicillanate (5b) as a beta-lactamase stable derivative with useful activity against Enterobacteriaceae, and disodium 6 beta-[D-2-(4-aminophenyl)-2-sulfoacetamido]-6 alpha-methoxypenicillanate (6e) with slightly lower activity against the Enterobacteriaceae but more active against Pseudomonas aeruginosa.

The purpose of the present investigation was to study the effects of an arm ergometer training programme on several physiological variables of recreational wheelchair subjects. Ten paraplegics (5 experimental, 5 control) were tested prior to and immediately after a 2 month exercise regimen at 80% of peak heart rate (30 min per day, 5 days per week, for 8 consecutive weeks at 50 rev/min). The results demonstrated significant increases (P less than 0.05) in VO2max (1 min-1 & ml kg-1 min-1) and workload but only mild improvements in maximal heart rate and post exercise blood lactates. Body fat, vital capacity and forced expiratory volume did not change with training. Triceps lateralis fibre distribution and fast twitch (FT) fibre area were unaffected by the endurance training programme. However, slow twitch (ST) fibre area increased (P less than 0.05) with training. The results indicate that physiological variables of paraplegic subjects following an arm ergometer endurance training programme react similarly to changes previously observed in non-handicapped subjects. The values when compared with normals are low as a result of the relative inactivity of the subjects due to the lack of available exercise programmes for wheelchair people.

The purpose of the present study was to investigate the effects of 3-month sprint and endurance training programs on the vastus lateralis muscle fiber area and the activities of glycolytic (phosphofructokinase; PFK) and oxidative (succinate dehydrogenase; SDH) enzymes of adolescent boys. Enzyme activities were also determined after a subsequent 6-month detraining period. Endurance training resulted in significant increases in VO2max (58.4 to 64.3 ml . min-1 . kg-1), in ST and FTa fiber area (6.0 to 7.3 and 8.0 to 10.4 microns 2 x 10(3), respectively), and in SDH activity (6.4 to 9.1 IU). After detraining VO2max and SDH activity returned to pretraining levels. Sprint training resulted in a significant increase only in PFK activity (28.1 to 33.9 IU), which was also abolished in the detraining period. These data demonstrate that in adolescent boys skeletal muscle enzyme changes are specific to the mode of training and that they are similar in direction but different in magnitude to those found in adults.

The effects of simple-carbohydrate (CHO)- and complex-CHO-rich diets on skeletal muscle glycogen content were compared. Twenty male marathon runners were divided into four equal groups with reference to dietary consumption: depletion/simple, depletion/complex, nondepletion/simple, and nondepletion/complex. Subjects consumed either a low-CHO (15% energy [E] intake), or a mixed diet (50% CHO) for 3 days, immediately followed by a high-CHO diet (70% E intake) predominant in either simple-CHO or in complex-CHO (85% of total CHO intake) for another 3 days. Skeletal muscle biopsies and venous blood samples were obtained one day prior to the start of the low-CHO diet or mixed diet (PRE), and then again one day after the completion of the high-CHO diet (POST). The samples were analysed for skeletal muscle glycogen, serum free fatty acids (FFA), insulin, and lactate and blood glucose. Skeletal muscle glycogen content increased significantly (p less than 0.05) only in the nondepletion/simple group. When groups were combined, according to the type of CHO ingested and/or utilization of a depletion diet, significant increases were observed in glycogen content. Serum FFA decreased significantly (p less than 0.05) for the nondepletion/complex group only, while serum insulin, blood glucose, and serum lactate were not altered. It is concluded that significant increases in skeletal muscle glycogen content can be achieved with a diet high in simple-CHO or complex-CHO, with or without initial consumption of a low-CHO diet.

A game-simulated hockey task has been developed to closely approximate the actions in a hockey game including forward and backward skating, stops, starts, shooting and passing. As well, the test is similar to game conditions for number of shifts, activity time per shift, activity time per play and total active time on the ice. The purpose of this study was to measure the glycogen depletion during the task and to compare this with laboratory tasks and actual game conditions. The results demonstrate that the simulated tasks resembles on ice conditions during a game for heart rate and glycogen depletion. The preferential glycogen utilization by ST fibres but great depletion in FT fibres as well suggests that the task is strenuous enough to stimulate both FT and ST motor units.

To measure the amounts of dieldrin and carbofuran lost to the environment, we incorporated them into soils in small (0.6-1.1 ha) watersheds in separate years. The disappearance of each was monitored by periodically measuring residues in the soil, runoff, maize plants, and overlying air (dieldrin only). Soil residues were nonuniformly distributed. Best estimate for the time for 95% disappearance of dieldrin from the soil was 12.8 years. Carbofuran disappearance conformed to a first-order reaction and gave 95% disappearance times ranging from 145 to 434 days, depending on soil pH, moisture, and temperature. Runoff losses of both pesticides were highest in rainfalls during the first month after application. Over the season, dieldrin losses ranged up to 2.3% of that applied and were concentrated in the solids. Carbofuran losses in runoff occurred largely in the water and comprised up to 1.9% of the application. More than twice as much carbofuran (and metabolites) as dieldrin was accumulated in the maize plants, mainly in the leaves. Volatilization was an important route of dieldrin loss, amounting in the first year to 4.5% of that applied. Volatility of carbofuran, which was only 1/18th that of dieldrin in a laboratory test, was not measured in the field. The data show that use of optimum management practices can substantially reduce the environmental impact of agricultural applications of these pesticides.

Left ventricular size following endurance, sprint, and strength training. Med. Sci. Sports Exercise, Vol. 14, No. 5, pp. 344-347, 1982. Left ventricular dimensions in adolescent boys were determined before and after three types of training regimens: endurance (END), N = 8, means = 16.8 yr; sprint (SPR), N = 8, means = 16.3 yr; strength (STR), N = 12, means = 18.7 yr. With training the END group significantly increased VO2max in 1 X min-1 (3.71 +/- 0.27 to 4.16 +/- 0.57, P less than 0.05) and in ml X min-1 X kg-1 (58.4 +/- 5.6 to 64.2 +/- 5.5, P less than 0.05). The SPR group increased VO2max in 1 X min-1 (3.63 +/- 0.63 to 3.98 +/- 0.78, P less than 0.05) but not in ml X min-1 X kg-1 (59.5 +/- 4.1 to 63.2 +/- 5.4) because body weight increased from 61.2 +/- 10.5 to 63.1 +/- 10.7 kg (P less than 0.05) with no change in percent body fat. The STR training group significantly improved upper body strength. Despite these specific training adaptations no significant modifications were found for interventricular and left ventricular posterior wall thickness or for left ventricular internal diameter in either training group. However, calculated left ventricular mass was slightly but significantly higher by 10% and 4% in the END and STR training groups, respectively. These small increases in calculated left ventricular mass with short-term training are probably caused by small but insignificant increases in left ventricular internal diameter secondary to a training bradycardia (END group: 76 +/- 8 to 64 +/- 1 beats X min-1) and to increased diastolic filling time rather than to true cardiac hypertrophy. Significant increases in aerobic capacity and in strength can occur without modification of left ventricular dimensions.

Endurance capacity and the effects of different post-exercise states on skeletal muscle glycogen have been studied in rats trained by swimming or running and in sedentary controls. Regular endurance exercise resulted in increased skeletal muscle glycogen stores. A greater depletion was observed in trained animals than in non-trained animals after a training bout or exhaustive exercise. While muscle glycogen levels did not reflect a differential training stimulus (running vs swimming), swimming as a measure of exhaustive exercise was deemed invalid because of the ability of trained swimmers to avoid stenuous exercise by an alteration of swimming pattern.

A comparison of the influence of simple and complex carbohydrate (CHO) consumption on adipose tissue- and skeletal muscle-lipoprotein lipase activity (AT-LPLA, SM-LPLA) was examined. Twenty male marathon runners were divided into two equal dietary groups: simple-CHO and complex-CHO. Half of the subjects in each group consumed either a low-CHO (15% energy [E] intake), or a mixed diet (50% CHO) for 3 days. Immediately following this dietary period, the subjects consumed a CHO-rich diet (70% E intake) predominant in simple-CHO or in complex-CHO for an additional 3 days. Thereafter, all subjects returned to a normal mixed diet. Skeletal muscle biopsies, adipose tissue aspirations, and venous blood samples were obtained prior to dietary manipulation (PRE), upon completion of the 6 day diet (POST I), and 2 weeks after returning to a normal diet (POST II). The samples were analysed for AT-LPLA, SM-LPLA, serum insulin, and free fatty acids (FFA), and blood glucose, and lactate. SM-LPLA fell 71% from PRE values of 0.39 +/- 0.30 mu mol.g-1.h-1 to POST I values of 0.11 +/- 0.09 mu mol.g-1.h-1 (means +/- SD) (p less than 0.05), after a complex-CHO diet. However, the simple-CHO diet did not alter SM-LPLA. AT-LPLA similarly decreased (p less than 0.05) after the complex-CHO diet, and no significant decrease was noted after the simple-CHO diet.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of dietary manipulation (low- or high-carbohydrate) on performance of a short-duration exercise were studied with endurance- and intermittent-trained athletes. Eight subjects performed a depletion drill of 10 one minute workbouts at 7 W/kg and 85 rpm on a cycle ergometer. The subjects followed a dietary regimen of three days on a low-carbohydrate diet followed by three days on a high-carbohydrate diet. Muscle biopsy samples were taken immediately prior to and immediately after the testing sessions. Dietary manipulation did not affect resting muscle glycogen levels. However, subjects accustomed to continuous training regimens used less glycogen, produced less muscle lactate and exercised longer than subjects accustomed to intermittent training programs. These biochemical changes appeared to be related to the fibre type distribution and the training background of the athletes.

The sport of Greco-Roman wrestling is relatively new in North America. However, this is the national sport of seven European countries and a great deal of research literature is available. The purpose of the present investigation was to establish baseline data for Canadian Greco-Roman wrestlers for a data bank which can be used to compare with World Class wrestlers. The results indicate that the Canadian National Team is made up of athletes with only average values for the physiological measures taken. However, the correlation between wrestling success and the physiological parameters measured is 0.91.

Cardiovascular and skeletal muscle adaptations were studied before and after 6 mo of physical training in patients with coronary artery disease and exertional angina pectoris. Symptom-limited exercise capacity increased by 41% (470 +/- 30 to 665 +/- 35 kg.m.min-1; n = 29, P less than 0.001) with training as did skeletal muscle succinate dehydrogenase activity (1.75 +/- 0.24 to 3.31 +/- 0.24 IU; n = 23, P less than 0.001) and the areas of muscle fibers (type I from 43.6 +/- 3.3 to 54.4 +/- 3.3 micrometers 2 X 10(2); n = 21, P less than 0.05 and type II from 43.9 +/- 2.4 to 57.2 +/- 5.1 micrometers 2 X 10(2); P less than 0.01). At the same submaximal exercise intensity (mean 355 +/- 100 km.m.min-1), plasma catecholamines (1.31 +/- 0.14 to 1.07 +/- 0.09 ng.ml-1; n = 13, P less than 0.05), heart rate (115 +/- 3 to 97 +/- 3 beats/min; n = 29, P less than 0.001), and systolic blood pressure (171 +/- 4 to 143 +2- 4 mmHg; n = 29, P less than 0.001) were significantly reduced after training. Maximal coronary sinus blood flow (192 +/- 10 to 208 +/- 9 ml.min-1; n = 29, P less than 0.05) and left ventricular oxygen consumption (23.2 +/- 1.5 to 25.8 +/- 1.6 ml.min-1; n = 24, P less than 0.05) were increased by 8 and 11%, respectively, after training. The improvement in exercise capacity with training in patients with exercise is secondary to a reduction in myocardial oxygen requirements during subangina levels of exercise and partly to a small increase in maximal myocardial oxygen consumption. The skeletal muscle adaptations with training were not related to other indices of training such as the reduced exercise heart rate or increased symptom-limited exercise capacity.