Changes in aerobic and anaerobic fitness in the Polish army paratroopers during their military service.

BACKGROUND: The purpose of this study was to estimate changes in the aerobic- and anaerobic-dependent performance tasks in paratroopers during 18 mo of their military service. METHODS: There were 39 Polish Army recruits, enlisted to the paratroops, who volunteered for this study. The subjects were examined on enlisting and then after 3, 12, and 18 mo of the service. Anthropometry, aerobic capacity (V(O2max), V(O2OBLA), PWC170), anaerobic power and capacity (using Wingate test), performance in the repeated supramaximal exercises and motor performance indices (battery tests for locomotory endurance, agility, explosive power, strength and muscular endurance) were assessed. RESULTS: Military training produced a significant (p) < 0.05) increase in the body weight (by 4%), lean body mass (by 5.7%) and selected body girths. This was associated by the decrease in body fat from 15% to 13.1%). No significant changes in the aerobic fitness indices were noted. The studied soldiers showed significant increases in anaerobic power (by 5.9%) and anaerobic capacity (by 9.7%) accompanied by a substantial improvement in the performance in the repeated supramaximal exercises. There were also striking improvements in the variables which reflected muscular endurance and explosive power (by 32 78%), a substantial increase in the variables which reflected locomotory endurance (by 12.4%), agility (by 13.7%) and speed (by 11%), and a small rise in the static strength (by 4%). CONCLUSIONS: Overall, the present results show that the military training for paratroopers improves the motor performance and the anaerobic-dependent performance tasks and leads to favorable changes in the body composition but does not result in the improvement of aerobic fitness.

Effect of ubiquinone on exercise-induced lipid peroxidation in rat tissues.

Changes in the amount of thiobarbituric acid-reactive substances (TBARS), an index of the lipid peroxidation, were estimated in liver, heart, and the red and white components of gastrocnemius muscle of control (C) and ubiquinone-treated rats (T, 10 mg.kg-1 daily, for 4 weeks) at rest, and 3 and 24 h after running until the rats were exhausted. The activity of creatine kinase in serum and the level of the non-protein sulphhydryl groups (NP-SH) in the above organs were also determined. The running time until exhaustion was longer in T than in C [83.0 (SD 13.8) vs 72.2 (SD 14.8) min, P < 0.05]. The exercise resulted in a significant increase (P < 0.01) in the TBARS amounts in all the tissues obtained from C and in the liver and heart of T. The postexercise amounts of TBARS were significantly higher (P < 0.01) in C than in T. The resting amounts of NP-SH in the heart and liver were significantly higher (P < 0.05) in C compared to T. The exercise led to a decrease in the NP-SH content in the heart and liver (P < 0.05) of C but did not seem to affect the NP-SH contents in these tissues in T. No effect of ubiquinone treatment on postexercise increase in the serum creatine kinase concentration was found. It was concluded that in rats ubiquinone treatment markedly suppresses exercise-induced lipid peroxidation in such organs as liver, heart and gastrocnemius muscle.

Changes in concentrations of tissue free radical marker and serum creatine kinase during the post-exercise period in rats.

Changes in the concentrations of thiobarbituric acid-reactive substances (TBARS), an index of lipid peroxidation in liver, heart and soleus muscle, were studied in trained (T) and untrained (U) rats throughout a period of 48-72 h following running until exhaustion. Creatine kinase (CK) concentration in serum was also determined. The running time till exhaustion in group T was significantly longer than in group U [174.5 (SEM 9.8) vs 92.7 (SEM 8.3) min, P < 0.01]. In group U TBARS concentration in investigated tissues increased significantly (P < 0.01) after exercise with the peak values observed 3 h after running. The postexercise increase in the TBARS concentration persisted longer in the soleus muscle (48 h) than in the liver or heart (3 h). A postexercise increase of TBARS was observed in group T only in the liver. The influence of training on the TBARS content depended on the kind of tissue. The TBARS concentrations in the liver at rest and immediately after the exercise were lower in group U than in group T. In contrast, TBARS concentrations in the heart and soleus muscle were higher in group U than in group T. The exercise resulted, in both groups, in a rise of serum CK concentration, peak values being observed 3 h following the exercise. Postexercise concentrations of CK were considerably lower in group T than in group U [3 h postexercise: 1740 (SEM 170) vs 2750 (SEM 231) U.l-1 P < 0.01]. A positive correlation (r = 0.66, P < 0.05) between TBARS content in muscle and serum CK concentration was found only in group U. The results obtained indicated that the generation of lipid peroxidation products in the soleus muscle was intensified for a relatively long time after the exercise. Endurance training decreased the susceptibility of tissues to the action of free radicals. However, this influence of training was more pronounced in the heart and soleus muscle than in the liver.

Changes in some haematological and metabolic indices in young horses during the first year of jump-training.

Effects of an 18 min exercise test, on three separate occasions during a one year jump-training programme, was studied in seven horses. Determinations were carried out on venous blood for packed cell volume, haemoglobin, total protein, lactate and pyruvate, glucose, free fatty acids, insulin, glucagon, blood gases, bicarbonate, pH, aldolase, aspartate aminotransferase and alanine amino-transferase. Exercise caused a slight increase in lactate and pyruvate, total protein, aldolase, alanine aminotransferase, pO2, bicarbonate and pH. Glucose, free fatty acids and pCO2 levels decreased. Training caused no significant difference in these changes. However, during the year, increases in lactate and decreases in pH (resting levels) were observed.

Physiological responses to working with fire fighting equipment in the heat in relation to subjective fatigue.

Heart rate (HR), rectal temperature (Tre), blood pressure, temperature and relative humidity changes inside clothing were measured on 18 professional firemen (mean age 29.4 +/- 7.4 yr, VO2 max 41.4 + 8.8 ml kg-1 min-1) wearing fire fighter's uniforms (SU) or aluminized, fire resistant, impermeable clothing with self contained breathing apparatus (FE). The subjects exercised on a cycle ergometer with a work load of 1.5 W kg-1, at 39 +/- 1 degree C and at 70 +/- 5% relative humidity. They stopped exercising at a point of subjective fatigue and overheating which--according to their judgement--would cause them to stop working during real fire fighting. The working time until fatigue for subjects wearing FE was considerably lower than the corresponding value for SU. The HR and Tre values rose progressively throughout the exercise with no tendency to reach a plateau. In some cases the HR reached near maximal level. The Tre continued to rise even during 10 min of recovery and in many subjects exceeded 39 degrees C. These data showed that despite spontaneous termination of exercise, the limit of tolerance was reached by most of the subjects.

Fluostigmine effect on glycogen level in the skeletal muscle.

Fluostigmine in a dose not producing evident toxicity reduced the glycogen content in the gastrocnemius muscle in rats, with a consequent decrease of glycogen utilization during contractions of the muscle induced with direct tetanic stimuli. Administration of atropine or atropine with obidoxime failed to change this effect of fluostigmine. The authors suggest that the effect is not due to disturbances of the cholinergic system function.

[Toxicity of volatile thermal degradation products of conveyer belts studied in guinea pigs]. / Badania toksycznosci dla swinek morskich lotnych produktów spalania pasów przenosnikowych.

The toxicity to guinea pigs of the thermal degradation products of conveyor belts, preliminarily filtered through mining gas-mask container, has been tested. The smoke from rubber belts was more toxic than that from polyvinyl chloride. Addition of coal during burning decreased the toxicity of smoke. The test products caused an increase in serum aspartate and alanine aminotransferase, and pulmonary emphysema and edema. In the animals that survived the early period post intoxication, bronchopneumonia as well as pneumonia of parenchymatous type and small degeneration lesions in the liver and kidney have been found.

[Further studies of the toxicity of volatile thermal degradation products of conveyor belts]. / Dalsze badania toksycznosci lotnych produktów spalania pasów przenosnikowych.

Toxic effects of the thermal degradation products of polivinyl chloride and rubber conveyor belts, preliminarily filtered through modified mining gas-mask container were studied in guinea pigs. The smoke concentration was approximate to the one found in mines near the fire during minimal ventilation (0.15 m/sec.) Within 60 min. exposure the test products showed slight irritative effects and caused a moderate lung injury and small degenerative lesions in the liver and kidney. All these changes were rather reversible and did not involve any risk to the animals' lives. The modified container reduced the toxicity of the test substances much more than did the hitherto used mining gas-mask container.

[Toxic effect of volatile products of thermooxidizing decomposition of conveyor belts]. / Badania toksycznego dzialania lotnych produktów termooksydacyjnego rozkladu pasów przenosnikowych.

Toxic effects of thermo-oxidizing decomposition products of conveying belts made of PVC and rubber have been tested. The resultant smokes were passed through a protective absorber. During 14-days' post-exposure observation, an increased activity of asparagine, aminotransferase and in some animal alanine aminotransferase was found. Moderately increased pathomorphological changes were found in lungs (emphysema, oedema interstitial and bronchogenic inflammations), along with slight degenerative changes in the liver and kidneys. In the peripheral blood, increased amounts of erythrocytes and leukocytes were found.

Neuromuscular function in fluostigmine intoxication.

In experiments with isolated nerve-diaphragm preparation and intact anterior tibial muscle of the rat, it was found that repeated administration of fluostigmine (1 to 30 days) caused a decrease of the indirectly elicited tetanic response and post-tetanic depression of twitch response. Impairment of neuromuscular transmission increased during the first days of treatment. In the following period marked recovery occurred in spite of further fluostigmine administration. The recovery of neuromuscular function was much more pronounced in diaphragm preparation than in the anterior tibial muscle. It was not associated with any recovery in the activity of inhibited acetylcholinesterase. The sensitivity of the neuromuscular junction to carbachol increased during the first days of treatment and then decreased in the later stage. The sensitivity to d-tubocurarine in the diaphragm preparation decreased on the tenth day of treatment and returned to normal value after 30 days. In the anterior tibial muscle the sensitivity to d-tubocurarine slightly decreased on the fifth day, and after 20 to 30 days, was markedly increased. The underlying mechanisms are discussed.

Adaptation of the neuromuscular junction to chronic acetylcholinesterase inhibition due to phospholine treatment.

The disturbances of neuromuscular transmission due to chronic (1 to 30 days) administration of phospholine to rats were investigated upon the isolated diaphragm preparation. Phospholine treatment impaired the ability of the muscle to maintain tetanic contraction in response to indirect stimulation and caused post-tetanic depression of twitch responses. In the later stage marked recovery of neuromuscular function occurred in spite of further phospholine administration. This recovery was not accompanied by any increase in the already lowered acetylcholinesterase activity. The concentration of d-tubocurarine needed to block twitch response increased during the first days of phospholine treatment and then, during the following period gradually returned to the normal level. The concentration of carbachol needed to block twitch response during 2 to 30 days of continued treatment was higher than that in control animals. The possible explanations for the spontaneous recovery of neuromuscular function are discussed.

The effect of certain electrolytes on neuromuscular transmission disturbances evoked by direct action of phospholine on synaptic structures.

In an isolated preparation of rat diaphragm stimulated indirectly (12 impulses per minute) after total inactivation of acetylcholinesterase phospholine reduced the amplitude of the response proportional to its concentration. The rise in the concentration of potassium, magnesium or calcium in the incubation fluid failed to alleviate the disturbances produced by phospholine. Phospholine increased significantly reduction of response amplitude caused by increased calcium and magnesium concentration and increased to a small extent response depression caused by raised potassium concentration. The obtained results, point out that phospholine exerts a direction on the neuromuscular junction which is connected with the postsynaptic action of this agent.

Preliminary screening of anticholinergic effect of new 1,3-dioxolane and 1,3,-dioxane derivatives.

Some of the 28 investigated new derivatives show distinct anticholinergic activity. The greatest activity, that of 2-cyclohexyl-2-phenyl-5-piperidinodioxane-1,3 was greater than of the atropine sulfate.

Preliminary screening of anticholinergic effect of some new derivatives of glycolic and aminoacetic acids.

The anticholinergic effect of some new alkylaminoalkyl esters of benzilic, cyclohexyl, 1-hydroxycyclohexyl, piperidino-and morpholino acetic acids (Table 1) was evaluated. Only benzilic acid esters were active and the 2-N-piperidinoaminoethyl benzilate hydrochloride (ANC-30) has the highest pA2 value.

Central therapeutic effects of dihydroderivative of pralidoxime (pro-2-PAM) in organophosphate intoxication.

Central actions of pro-2-PAM (dihydroderivative of 2-PAM) and 2-PAM in poisonings with DFP have been studied. It was shown that pro-2-PAM significantly increased activity of DFP inhibited acetylcholinesterase in the brain, quickly ceased the DFP-induced paralysis of respiration, partially normalized the DFP-induced abnormalities in electrocorticogram and increased the convulsive dosis of DFP. Effects of 2-PAM in these experiments were negligible.

Protective effects of a series of new pyridinium derivatives against inhibition of acetylcholinesterase by fluostigmine.

The protective effects of a series of new pyridinium derivatives against inhibition of acetylcholinesterase (AChE) by fluostigmine was studied in vitro on human erythrocytes. It was stated that some of these compounds exhibit protective action for AChE against inhibition by fluostigmine. The best protective index had N-methyl-4-[gamma-pyridyl]-pyridinium iodide.

Central anticholinergic effects of N-ethyl-2-pyrrolidylmethyl-cyclopentylphenyl glycollate.

The following effects of N-ethyl-2-pyrrolidyl-methyl-cyclopentylphenyl glycollate (PMCG) have been studied: effects on aggressive behaviour in mice and on general behaviour in rats, protective effects against central action of arecoline and nicotine in mice, thermo-regulatory effects in mice, protective action in poisonings with fluostigmine in mice and rats, and effects on bioelectrical activity of the brain in cats. It was stated that PMCG possesses a strong central anticholinergic activity blocking predominantly central muscarinic receptors; PMCG had also strong protective effects in anticholinesterase intoxications. It is suggested that this drug could have antiemotional and antiparkinsonian properties.