The effect of diminished metabolic acidosis on thermoregulatory response during exercise.

It was reported that metabolic acidosis inhibits the activity of warm-sensitive hypothalamic neurons. The present study was designed to test the hypothesis that metabolic alkalosis may improve heat loss during intensive exercise in men. Fifteen male subjects aged 22-24 years were submitted to incremental exercise on two randomized occasions one week apart. During the bicarbonate trial exercise was preceded by ingestion of NaHCO3 at a dose 250 mg/kg whilst during the placebo trial lactose was administered. Exercise load was increased every 3 min by 30 W until volitional exhaustion. Ambient temperature was kept at 23-24°C and humidity 50-60%. Tympanic and skin temperatures were recorded and the rate of sweating was assayed by humidity measurement of nitrogen flowing through a capsule attached to the mid posterior chest. Total sweat loss was determined by the changes in body mass. Venous blood samples were taken before exercise and at the end of each workload for determination of acid-base parameters. The subjects attained similar maximal workload in the two tests (260 ± 6 W) with heart rate 185 ± 6 beats/min. Blood concentration of hydrogen ions was lower (p < 0.001) in the bicarbonate than in the placebo trial throughout the whole exercise period. There were no significant differences between these tests in tympanic and mean skin temperatures, sweating rate and total sweat loss. The present data showed that in men attenuation of metabolic acidosis by bicarbonate ingestion did not influence thermoregulation during incremental exercise performed until volitional exhaustion, possibly due to too short duration of exertional uncompensated metabolic acidosis.

Psychomotor Performance after 30 h of Sleep Deprivation Combined with Exercise.

Sleep deprivation (SD) usually impairs psychomotor performance, but most experiments are usually focused on sedentary conditions. The purpose of this study was to evaluate the influence of 30 h of complete SD combined with prolonged, moderate exercise (SDE) on human psychomotor performance. Eleven endurance-trained men accustomed to overnight exertion were tested twice: in well-slept and non-fatigued conditions (Control) and immediately after 30 h of SDE. They performed a multiple-choice reaction time test (MCRT) at rest and during each workload of the graded exercise test to volitional exhaustion. At rest, the MCRT was shorter after SDE than in the Control (300 ± 13 ms vs. 339 ± 11 ms, respectively, p < 0.05). During graded exercise, there were no significant differences in MCRT between groups, but the fastest reaction was observed at lower workloads after SDE (158 ± 7 W vs. 187 ± 11 W in Control, p < 0.05). The total number of missed reactions tended to be higher after SDE (8.4 ± 0.7 vs. 6.3 ± 0.8 in Control, p = 0.06). In conclusion, SDE is different from SD alone; however, well-trained men, accustomed to overnight exertion can maintain psychomotor abilities independently of the extent of central fatigue. Exercise can be used to enhance psychomotor performance in sleep-deprived subjects in whom special caution is required in order to avoid overload.

ANGPTL4, IL-6 and TNF-α as regulators of lipid metabolism during a marathon run.

The aim of the study was to reveal whether marathon running influences regulators of lipid metabolism i.e. angiopoietin-like protein 4 (ANGPTL4), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α). Plasma concentration of ANGPTL4, IL-6, TNF-α and lipids were determined in samples collected from 11 male runners before the marathon, immediately after the run and at 90 min of recovery. Plasma ANGPTL4 increased during exercise from 55.5 ± 13.4 to 78.1 ± 15.0 ng/ml (P < 0.001). This was accompanied by a significant increase in IL-6, TNF-α, free fatty acids (FFA) and glycerol (Gly) and a decrease in triacylglycerols (TG). After 90 min of recovery ANGPTL4 and TG did not differ from the exercise values, while plasma IL-6, TNF-α, FFA and Gly concentration were significantly lower. The exercise-induced increase in plasma concentration of ANGPTL4 correlated positively with the rise in plasma IL-6, TNF-α, FFA and Gly and negatively with the duration of the run. The increase in plasma IL-6 and TNF-α correlated positively with the rise in Gly. Summarizing, marathon running induced an increase in plasma ANGPTL4 and the value was higher in faster runners. The increase in plasma FFA, IL-6 and TNF-α concentration during a marathon run may be involved in plasma ANGPTL4 release, which could be a compensatory mechanism against FFA-induced lipotoxicity and oxidative stress. All of the analyzed cytokines may stimulate lipolysis during exercise.

Sports Elite Means Vaccine Elite? Concerns and Beliefs Related to COVID-19 Vaccines among Olympians and Elite Athletes.

(1) Background: The purpose of this study was to investigate the concerns and beliefs of Olympians and elite athletes toward COVID-19 vaccination. (2) Methods: The study was framed by a quantitative method and was conducted using the PAPI (pen and paper interview) technique among 895 Polish elite athletes representing 34 sports. (3) Results: Three-quarters (76.3%) of the athletes were vaccinated against COVID-19; statistically participants were more likely to be women, and athletes who participated in the Olympic Games. Four in ten (39.2%) were in favor of vaccination. Athletes were mainly concerned that COVID-19 would exclude them from training/competition (19.3%) and could have a long-term impact on their health (17.2%). Athletes who were vaccinated reported much higher confidence in the composition of the vaccine and the doctors who recommended vaccination than unvaccinated athletes. Athletes who competed at the Olympic level were more likely than others to disbelieve that vaccines were produced too quickly and were not well tested. National-level athletes showed the highest degree of distrust in the government regarding COVID-19 vaccination, with one in six respondents distrusting doctors with respect to COVID-19 vaccination. Four in ten respondents said they were in favor of vaccination. (4) Conclusions: Athletes' attitudes toward COVID-19 vaccination were significantly influenced by their environment-especially coaches and relatives. The power of social norms with respect to the decision to vaccinate against COVID-19 was very strong. Therefore, it is essential to build awareness about preventive policies among athletes and their social environment.

Vaccine versus infection - COVID-19-related loss of training time in elite athletes.

OBJECTIVES: To determine the number of training days lost due to COVID-19 and vaccination against COVID-19 in elite athletes. DESIGN: Retrospective cohort study. METHODS: The questionnaire on the impact of vaccination and COVID-19 on training plans was filled out by 1073 elite Polish athletes who underwent routine medical screening between September and December 2021. RESULTS: COVID-19 was diagnosed in 421 subjects (39 %), of whom 26 % were asymptomatic. On the 10-point scale, <1 % of athletes had perceived severity of the disease above 8, whereas for 64 % it was 4 or below. Vaccination against COVID-19 was administered in 820 athletes (76 %), and adverse events were observed more frequently after the first dose than the second (69 % vs. 47 %). Influence on training (modified or lost) was declared by 369 of 421 (88 %) COVID-19 athletes, and by 226 of 820 vaccinated athletes (28 %). During the observation period, the average number of lost training days was 8.1 for COVID-19 and 2.6 for vaccination (p < 0.001). The cumulative number of person-days lost due to COVID-19 was 1041 versus 295 after vaccination thus, the average loss ratio was 1041/1073 = 0.97 vs. 295/820 = 0.36, respectively, p < 0.01. CONCLUSIONS: Athletes have a considerable loss of training days due to COVID-19. Vaccination against COVID-19 causes significantly smaller and predictable loss. This supports the inclusion of vaccination into prevention policies for athletes whenever they are available.

Elite athletes with COVID-19 - Predictors of the course of disease.

OBJECTIVES: The aim of the study was to identify predictors determining the course of COVID-19 and antibody response in elite athletes. DESIGN: Observational study. METHODS: Routine medical screening with physical examination, resting ECG, and laboratory tests including antibody response was performed 12-68 days after the diagnosis of COVID-19 in 111 athletes of different sports. RESULTS: Clinical symptoms were observed in 84% of subjects. The severity of COVID-19 was mild in 82% of athletes and moderate in 2% of cases. Athletes aged above 26 and male were more likely to develop symptomatic COVID-19. Asymptomatic subjects were younger and predominantly female. In 18% of subjects, symptoms were still present 20 (12-68) days (median and range) since positive diagnosis. Antibody response was observed in 88% of athletes, and its magnitude correlated with time since diagnosis of COVID-19 (RT-PCR), fatigue, fever, and conjunctivitis. There were no differences in antibody response between groups distinguished by sports discipline (p = 0.50), and sex (p = 0.59), and antibody response did not correlate with BMI (p = 0.12), age (p = 0.13), the number of symptoms (p = 0.43) or their duration (p = 0.19). CONCLUSIONS: The severity of COVID-19 in elite athletes is predominantly mild and without complications. Athletes can return to sport after two symptom-free weeks and additional heart screening is usually not required. Determination of antibodies has been shown to be a useful indicator of a previous COVID-19 disease, and some symptoms can be used as predictors of antibody response.

Safety and Impact on Training of the Influenza Vaccines in Elite Athletes Participating in the Rio 2016 Olympics.

OBJECTIVE: The aim of the study was to evaluate the safety and tolerance of influenza vaccines for the northern and southern hemispheres in Polish elite athletes participating in the Rio 2016 Olympics. DESIGN: Prospective, observational, cohort study. SETTING: Institutional level. PARTICIPANTS: Ninety-seven athletes vaccinated only with the northern hemisphere vaccine; 98 athletes received the southern hemisphere vaccine alone, whereas 39 athletes were vaccinated with both vaccines. INTERVENTIONS: The athletes were vaccinated with a trivalent, inactivated influenza vaccine recommended for the northern hemisphere 2015/2016 and then with the vaccine recommended for the southern hemisphere 2016. Athletes kept a diary of adverse events and effects (if any) on training for 6 days after vaccination. MAIN OUTCOME MEASURES: The percentage of general and local adverse events, number of lost or modified training sessions. RESULTS: Significantly more local adverse events (pain and redness) were found in the group immunized with the vaccine for the northern hemisphere. There were no differences in the frequency of general adverse events and influence on training between groups. Of total 273 athletes who had 1911 training days during 6 days after vaccination, 6 athletes (2.2%) lost 13 training days (0.7%) and 16 athletes (5.9%) had to modify 34 (1.7%) training days within first 2 days after vaccination. CONCLUSIONS: Athletes tolerated influenza immunization well. If they are going to travel to the other hemisphere during the influenza season, the use of the second influenza vaccine should be advised. Athletes should anticipate modification of trainings for 2 days after vaccination.

Is vitamin D status reflected by testosterone concentration in elite athletes?

Vitamin D is a nutrient whose active form affects tissues as a hormone and possibly enhances performance. One plausible mechanism is by increasing testosterone concentration, which is established as an important factor for athletic performance. Therefore the aim of the study was to examine the relationship between plasma concentration of 25(OH)D and testosterone in Polish elite track and field athletes depending on vitamin D status, season, training period, body composition, sex, type of training, sun exposure and vitamin D supplementation. Plasma concentrations of 25(OH)D and testosterone were measured in all seasons within two years in athletes (70 females, 79 males) who represent strength (n = 103) and endurance (n = 46) kinds of sports, in the preparatorycompetitive season and transition period. There were no differences in 25(OH)D concentration between male and female athletes, insufficiency [25(OH)D < 30 ng/ml] was observed in 32.9%, whereas deficiency [25(OH)D < 20 ng/ ml] in 3.2%. Circannual rhythm was noted for vitamin D but not for testosterone concentration; no correlations between them were found either in strength or endurance athletes or between 25(OH)D and body composition. Testosterone concentration was higher in the transition period than in the preparatory-competition period only in male athletes. Higher 25(OH)D was observed in athletes who trained during winter in Africa (higher sun exposure) or used oral supplementation, whereas the respective testosterone levels were unchanged. In athletes, testosterone concentration did not reflect vitamin D status. The widespread of inadequate vitamin D status among athletes, makes it vital to recommend them the regular monitoring of 25(OH)D concentration and use of reasonable supplementation.

Vitamin B12 Status and Optimal Range for Hemoglobin Formation in Elite Athletes.

BACKGROUND: Athletes and coaches believe in the ergogenic effect of vitamin B12 (which results from enhanced erythropoiesis) and they often insist on its unjustified supplementation. Therefore, our study aimed to assess the vitamin B12 status in Polish elite athletes and its influence on red blood cell parameters. METHODS: In total, 1131 blood samples were collected during six years from 243 track and field athletes divided into strength and endurance groups, as well as according to the declared use of vitamin B12 injections. RESULTS: An average vitamin B12 concentration in all subjects was 739 ± 13 pg/mL, with no cases of deficiency. A weak but significant relationship was found between vitamin B12 and hemoglobin concentrations. A significant increase in hemoglobin appeared from very low vitamin B12 concentration and up to approx. 400 pg/mL, while hemoglobin did not significantly change from 700 pg/mL and onwards. Vitamin B12 injections were used by 34% of athletes, significantly more often by endurance than by strength athletes. In athletes who declared no use of injections, a higher concentration of vitamin B12 was observed in the endurance group. CONCLUSION: The main finding of the present study is the determination of the range of vitamin B12 concentration which may favor better hemoglobin synthesis in athletes. They should regularly monitor vitamin B12 concentration and maintain the range of 400-700 pg/mL as it may improve red blood cell parameters. We might suggest application of a supplementation if necessary. Special attention is required in athletes with a vitamin B12 concentration below 400 pg/mL.

The Neglected Leg Lymphatic Vascular Changes in the Pathomechanism of Delayed Onset Muscle Soreness in Runners.

Background: Delayed onset muscle soreness (DOMS) in runners is classified as a leg muscle strain injury and presents with tenderness or stiffness to palpation and movement limitation. Most attention is directed at muscles but not at the mass of other limb soft tissues, including their lymphatic vasculature, although they undergo mechanical stress and bruises, edema, nail destruction, and pains contributing to symptoms. Methods and Results: The study was done on lower limbs of long-distance runners suffering from DOMS complaints. There were 16 runners, 11 males and 5 females, age 22-28, practicing long-distance running over the last 5 years, with body mass index (BMI) 23 ± 4. Inclusion criteria: three to five marathon runs per year and daily 3-5 km slow runs. Last long distance run 3 to 7 days before the investigation. Controls were six subjects initiating running, of the same age group and BMI. Testing of blood and lymph flow was done before and after standard ergometer 300 W 30 minutes cycling. The measurement methods were leg and big toe venous plethysmography, big toe capillary Doppler, tonometry of skin and deep tissues, lymphoscintigraphy, and indocyanine green (ICG) fluorescent lymphography. (a) Strain gauge plethysmography of the calf and big toe revealed a two- to three-times higher venous capacity in runners than in controls, (b) the increased toe venous capacity was confirmed by point Doppler recordings showing two- to three-times higher blood capillary flow compared to controls, (c) lymphoscintigraphy revealed retention of tracer in feet, dilated superficial and deep lymphatics, and enlarged popliteal and inguinal lymph nodes, and (d) ICG lymphograms showed confluents of accumulated fluid in foot and calf subcutaneous tissue with fluorescence level reaching 40%-50% compared to 20% in controls. Conclusion: Our results show that, 3-5 days after run, not only muscles but also skin and subcutaneous tissue reveal major tissue fluid accumulation, an overload bringing about functional lymphatic transport insufficiency. This may be an additional factor responsible for DOMS symptoms.

Antibody Response to Trivalent Influenza Vaccine in the Northern and the Southern Hemisphere in Elite Athletes.

Being frequent travelers, the elite athletes are advised to undergo an influenza vaccination. The aim of the study was to describe the antibody response to repeated trivalent, inactivated, split influenza vaccine, of different antigenic content, recommended for the Northern and the Southern Hemisphere, administered to sportsmen before the Olympic Games in Brasil in 2016. Fourteen athletes were included in the study. For both A/California/7/209/pdm09 A/H1N1/ antigen and A/Switzerland/971593/2013/A/H3N2/ antigen, higher seroconversion rates were obtained after the first than the second vaccination (10.2 vs. 1.5 and 10.6 vs. 3.0, respectively; p < 0.05 both). Conversion rates for B/Phuket/3073/2013, B/Brisbane/60/2008, and A/HongKong/4801/2014/A/H3N2/ antigens were lower. Nonetheless, the protection rate was greater than 70% for all antigens contained in both vaccines. The proportion of individuals demonstrating a high level of both protection rate and response rate was greater after the first than the second vaccination. We conclude that the immunological response after influenza vaccination is good in elite athletes and remains so after a second influenza vaccination required due to a different vaccine composition recommended for different hemispheres.

Psychomotor performance of Polish Air Force cadets after 36 hours of survival training.

INTRODUCTION: The preparation of Polish Air Force cadets for survival in isolation is a necessary element of their training, to demonstrate just how difficult can be the conditions they could encounter in a combat situation. Objective. The aim of the research was to assess the effect of long-term survival training on selected coordination motor skills in Air Force cadets. MATERIAL AND METHODS: Fifteen air force cadets aged 19.6±0.3 years exercised for 36 hours during survival training without the possibility to sleep. They were examined 4 times: Day 1 - before effort (training), Day 2 - after 24 hours training, Day 3 - directly after 36 hours training, Day 4 - next day, after an all night rest. They were examined for shooting and reaction time, the ability to maintain body balance, running motor adjustment, handgrip force differentiation, and on Days 1 and 3, exercise capacity was evaluated with a 1 mile walking test. RESULTS: The survival training resulted in significant decreases in maximum handgrip strength, corrected 50% max handgrip, maintenance of body balance and heart rate. No changes occurred in reaction time, running motor adjustment and shooting performance. Overnight rest did not result in recovery of any of the examined factors to the values observed on Day 1. CONCLUSIONS: Survival training combined with sleep deprivation mostly affected peripheral factors depending on strong action from both muscles and nervous system, whereas complex tasks involving short-term central alertness and moderate exertion were maintained. In order to improve performance, more endurance strength training, if possible combined with sleep deprivation, should be introduced in military training.

Seasonal Vitamin D Status in Polish Elite Athletes in Relation to Sun Exposure and Oral Supplementation.

Vitamin D does not only influence the musculoskeletal health and mineral homeostasis but it also affects cardiovascular, endocrine, nervous, immune and mental functions, thus it is of considerable importance for both physically active people and elite athletes. However, vitamin D deficiency is common worldwide and results from inadequate endogenous skin synthesis (insufficient ultraviolet B exposure) and diet. To improve the vitamin D status elite athletes often travel to lower latitude during winter. The aim of the study was to evaluate the seasonal vitamin D status in Polish elite athletes according to the sun exposure and oral supplementation. Serum concentration of 25-hydroxyvitamin D (25(OH)D) was measured in the years 2010-2014 in 409 elite athletes, who were divided into the following groups: OUTD-outdoor sports, represented by track and field athletes, who trained in Poland; IND-weightlifters, handball and volleyball players who trained indoors in Poland; SUN-track and field athletes who trained during Polish winter in lower latitude with high sunshine exposure; SUPL-track and field athletes who trained in Poland, had an inadequate vitamin D status (25(OH)D < 30 ng/ml) and were supplemented orally. Inadequate Vitamin D status was observed in 80% of OUTD and 84% of IND athletes in winter, whereas in summer the values amounted to 42% and 83%, respectively. The athletes exposed to sun in winter had significantly higher vitamin D concentration than OUTD group. Oral supplementation improved vitamin D concentration by 45%, whereas winter sun exposure caused its increase by 85%. Except for a few summer months an inadequate status of vitamin D was found in the majority of Polish elite athletes, with the deficiency level being similar to the one observed in non-athletic population. The most serious deficiency was observed in indoor disciplines. Adequate vitamin D status can be achieved by both increased sun exposure, especially in winter, and oral supplementation. Athletes should therefore routinely assess their vitamin D status and be educated how to approach their sunlight exposure, diet and supplementation.

Effects of supplementation with branched chain amino acids and ornithine aspartate on plasma ammonia and central fatigue during exercise in healthy men.

INTRODUCTION: Our previous studies showed only slight improvement in central fatigue, measured indirectly by psychomotor performance, after branched chain amino acids (BCAA) supplementation during various efforts in healthy men. It is hypothesised that hyperammonaemia resulting from amino acids metabolism may attenuate their beneficial effect on psychomotor performance; therefore, the L-ornithine L-aspartate (OA) as an ammonia decreasing agent was used. The aim of this study was to investigate the effectiveness of oral BCAA + OA supplementation to reduce plasma ammonia concentration and enhance psychomotor performance during exhaustive exercise in healthy men. MATERIAL AND METHODS: Eleven endurance-trained men (mean age 32.6 ± 1.9 years) performed two sessions (separated by one week) of submaximal cycloergometer exercise for 90 minutes at 60% of maximal oxygen uptake followed by graded exercise until exhaustion with randomised, double-blind supplementation with a total of 16 g BCAA and 12 g OA (BCAA + OA trial) or flavoured water (placebo trial). Before exercise, during both efforts and after 20 minutes of recovery multiple choice reaction time (MCRT), perceived exertion, heart rate and oxygen uptake were measured and venous blood samples were taken for plasma leucine, valine, isoleucine, ornithine, aspartate, free tryptophan (fTRP), ammonia, lactate and glucose determination. RESULTS: After ingestion, during both efforts and after 20 minutes of recovery the plasma concentrations of all supplemented amino acids were significantly increased, while the fTRP/BCAA ratio decreased in the BCAA + OA trial more than in the placebo trial. At the end of graded exercise plasma fTRP was lower and MCRT shorter in BCAA + OA than in the placebo trial (p < 0.05). At the end of prolonged exercise the plasma ammonia concentration was higher in BCAA + OA than in placebo trial (p < 0.05). Decreases in plasma ammonia during recovery were significantly higher in BCAA + OA than in the placebo trial. Plasma ammonia positively correlated with the total plasma BCAA and MCRT only in the BCAA + OA trial. The fTRP/BCAA ratio positively correlated with MCRT only in the placebo trial. CONCLUSIONS: Supplementation with BCAA and OA is a useful way to improve MCRT during high-intensity exercise and accelerate the elimination of ammonia at the recovery stage after exercise in healthy young men.

Thermogenic effect of glucose in hypothyroid subjects.

The importance of thyroid hormone, catecholamines, and insulin in modification of the thermogenic effect of glucose (TEG) was examined in 34 healthy and 32 hypothyroid subjects. We calculated the energy expenditure at rest and during oral glucose tolerance test. Blood samples for determinations of glucose, plasma insulin, adrenaline (A), and noradrenaline (NA) were collected. It was found that TEG was lower in hypothyroid than in control group (19.68 ± 3.90 versus 55.40 ± 7.32 kJ, resp., P < 0.0004). Mean values of glucose and insulin areas under the curve were higher in women with hypothyroidism than in control group (286.79 ± 23.65 versus 188.41 ± 15.84 mmol/L·min, P < 0.003 and 7563.27 ± 863.65 versus 4987.72 ± 583.88 mU/L·min, P < 0.03 resp.). Maximal levels of catecholamines after glucose ingestion were higher in hypothyroid patients than in control subjects (Amax-0.69 ± 0.08 versus 0.30 ± 0.07 nmol/L, P < 0.0001, and NAmax-6.42 ± 0.86 versus 2.54 ± 0.30 nmol/L, P < 0.0002). It can be concluded that in hypothyroidism TEG and glucose tolerance are decreased while the adrenergic response to glucose administration is enhanced. Presumably, these changes are related to decreased insulin sensitivity and responsiveness to catecholamine action.

Influence of aerobic training on neurohormonal and hemodynamic responses to head-up tilt test and on autonomic nervous activity at rest and after exercise in patients after bypass surgery.

BACKGROUND: Little is known about the influence of aerobic training on the neurohormonal and hemodynamic responses to head-up tilt (HUT) and on autonomic balance at rest and after exercise in optimally treated, low risk post-coronary artery bypass grafting (CABG) patients. METHODS: One hundred male patients, mean age 56 ± 6 years, 3 months after CABG, were randomized to either 6-week training on cycloergometer, 3 times a week, at 70-80% of max tolerated heart rate (HR) (training group, n = 50) or to a control group (n = 50). At baseline and at the end of the study, all patients underwent: (1) cardiopulmonary exercise test with HR recovery (HRR) assessment; (2) 60% HUT during which HR, blood pressure (BP), stroke volume (SV by impedance cardiography) were monitored and blood samples were taken for determination of plasma catecholamines and ANP levels, and plasma renin activity; (3) assessment of HR variability (HRV) in the time and frequency domains at rest. RESULTS: During the final tests, HUT-induced changes in HR, BP, SV, cardiac output, total peripheral resistance, and noradrenaline were significantly lower in training group than in controls. In addition, after training faster post-exercise HRR, increased SDNN and a tendency towards an increase in the high frequency HRV power spectrum were found. CONCLUSIONS: Aerobic training improved neurohormonal and hemodynamic responses to head-up tilt test and favorably modified sympatho-vagal balance in low risk post-CABG patients.

The effect of branched chain amino acids on psychomotor performance during treadmill exercise of changing intensity simulating a soccer game.

The present study was designed to determine changes in the multiple-choice reaction time (MRT) during treadmill running simulating locomotor activity during a soccer game and to examine the effect of branched chain amino acids (BCAA) ingestion on psychomotor performance during the effort. Ten male soccer players were submitted to BCAA and placebo trials at 1-week intervals in a randomized order. BCAA (7 g) or placebo were given 1 h before exercise in a double blind manner. The running test consisted of two 45 min exercise bouts separated by a 15-min passive rest period and the whole test ended with 20-min active recovery. Running-walking speed changed from 0 to 6.4 m·s⁻¹ according to the time-motion analysis of soccer match. During the test, blood samples were taken for lactate, glucose, free fatty acid, and catecholamine determination. Following placebo treatment, MRT shortened from 320 ± 18 to 271 ± 11 ms (p < 0.001) during the first exercise bout then it increased during the resting break to 303 ± 138 ms (p < 0.05). During the second bout, MRT decreased to 280 ± 13 ms (p < 0.001). During active recovery, further shortening of MRT was noted. During BCAA trial, MRT was shorter than during placebo trial by ~10% (p < 0.05) before and during exercise. No significant differences were found between BCAA and placebo trials in biochemical indices. It is concluded that BCAA supplementation might be recommended in sport activities that change in intensity and require quick responses to external signals (e.g., soccer and other team games).

Influence of dynamic training on hemodynamic, neurohormonal responses to static exercise and on inflammatory markers in patients after coronary artery bypass grafting.

BACKGROUND: Little is known about the influence of dynamic training on the hemodynamic and neurohormonal responses to static exercise and on inflammatory markers in optimally treated post-coronary artery bypass grafting (CABG) patients. METHODS AND RESULTS: One hundred and twenty male patients, aged 55±6 years, 3 months after receiving CABG, were randomized to either 6 weeks of aerobic training on a cycloergometer, 3 times a week, at a 70-80% of the maximum tolerated heart rate (HR) (training group, n=60) or to a control group (n=60). At baseline and at the end of the study, all patients underwent: (1) a cardiopulmonary test; (2) handgrip at 30% of maximal voluntary contraction for 3min in a sitting position during in which HR, blood pressure (BP), stroke volume (SV, by impedance cardiography), cardiac output (CO) and total peripheral resistance (TPR) were monitored; and (3) plasma level assessment of catecholamines, nitric oxide and inflammatory markers. During the final tests, handgrip-induced increases in HR, BP, and TPR (14% vs 27%, P<0.01) were lower, whereas SV and CO were higher (by 13% and 15%, respectively, P<0.05) in trained patients compared with controls. Moreover, a higher increase in nitric oxide level (46% vs 14%, P<0.01) and a lower increase in noradrenaline (11% vs 20%, P<0.05) were observed in trained patients compared with controls. Accordingly, training caused significant improvement in peak oxygen uptake per kilogram body weight (peak VO(2)) and inflammatory markers. CONCLUSIONS: Short-term dynamic training caused significant improvement of hemodynamic and neurohormonal responses to handgrip, cardiovascular fitness and inflammatory state.

[The most important clinical interactions among medicines used in cardiologic practice]. / Najwazniejsze interakcje pomiedzy lekami stosowanymi w kardiologii.

This article presents a review of the most important (from the cardiologic practice point of view) interactions among medicines administered to the patients suffering from cardiovascular diseases, in particular among medicines with cytochrome P450 (and its isoenzymes) dependent metabolism. Cardiovascular patients, often advanced in age, usually affected by concomitant diseases and compelled to take many different medicines are particularly exposed to side effects dependent on these interactions. The article describes both beneficial and unprofitable interactions among medicines administered in cardiology.