PurposeThe objective of this study was to investigate the effects of chronic Rhodiola rosea (R. rosea) supplementation on mental and physical performance, as well as hormonal and oxidative stress biomarkers.MethodsTwenty-six healthy male students received either R. rosea extract (600 mg/day; RR) or placebo (PL) in a randomized double-blind trial. Prior to supplementation (Term I) and following 4 weeks of supplementation (Term II), the students underwent psychomotor tests for simple and choice reaction time, included in the Vienna Test System. Also, the subjects performed VO2peak test. Blood samples were obtained before and after the test to measure the hormonal profile (cortisol, testosterone, and growth hormone), as well as the biomarkers of oxidative stress (lipid hydroperoxides, total antioxidant capacity, and superoxide dismutase) and muscle damage (creatine kinase).ResultsR. rosea ingestion shortened reaction time and total response time. Moreover, a greater relative increase in the number of correct responses was observed in RR group as compared to the PL group. No changes in endurance exercise capacity and hormonal profile were observed after R. rosea ingestion. R. rosea ingestion raised plasma total antioxidant capacity. It did not, however, affect other measured parameters.ConclusionChronic R. rosea ingestion does not affect physical performance, but can improve the results of some psychomotor tests (simple and choice reaction time) in young, healthy, and physically active men. The improvements in mental performance, however, at least in our study, seem not to be related to changes in cortisol release or antioxidant activity of R. rosea extract. Thus, the specific mechanisms responsible for these effects still need to be elucidated.

This study was designed to find out whether rest intervals and prevention of dehydration during prolonged exercise inhibit a drift in metabolic rate, body temperature and hormonal response typically occurring during continuous work. For this purpose in ten healthy men the heart rate (fc), rectal temperature (Tre), oxygen uptake (VO2), as well as blood metabolite and some hormone concentrations were measured during 2-h exercise at approximately 50% maximal oxygen uptake split into four equal parts by 30-min rest intervals during which body water losses were replaced. During each 30-min exercise period there was a rapid change in Tre and fc superimposed on which, these values increased progressively in consecutive exercise periods (slow drift). The VO2 showed similar changes but there were no significant differences in the respiratory exchange ratio, pulmonary ventilation, mechanical efficiency and plasma osmolality between successive periods of exercise. Blood glucose, insulin and C-peptide concentrations decreased in consecutive exercise periods, whereas plasma free fatty acid, glycerol, catecholamine, growth hormone and glucagon concentrations increased. Blood lactate concentrations did not show any regular drift and the plasma cortisol concentration decreased during the first two exercise periods and then increased. In conclusion, in spite of the relatively long rest intervals between the periods of prolonged exercise and the prevention of dehydration several physiological and hormonal variables showed a distinct drift with time. It is suggested that the slow drift in metabolic rate could have been attributable in the main to the increased concentrations of heat liberating hormones.

The aim of this study is to estimate the metabolic and hormone response in middle-aged women to acute physical aerobic exercise accompanied by music, the so-called "aerobics." The experiment (single 60-minute aerobics session) included 11 women aged between 30 and 50. The following variables were determined in blood samples collected from the participants four times (in fasting state [I], before exercise [II], after exercise [III], and after 12 hours of rest [IV]): concentration of lactic acid, glucose, free fatty acids, leptin, insulin, growth hormone, testosterone, and cortisol. Furthermore, the measurements included body mass before and after the exercise, and body temperature was taken in the auditory canal and on the forehead. The heart rate was registered during the exercise on a continuous basis. In all cases, the heart rate did not reach its maximum level, and on average, it amounted to approximately 70% of the maximum pulse rate. Therefore, this effort can be considered as submaximal. In all cases, we observed loss of body mass (from 0.2 to 0.7 kg) (p > 0.02) increase in the temperature measured on forehead. Significantly, accompanied by nonsignificant increase in the temperature measured on the tympanic membrane was registered. Single loading gives rise to change in hormone and metabolic profiles. Furthermore, a decrease in blood concentration of glucose before and after aerobics (p > 0.001) could be observed, and if the determination taken at measurement IV of glucose in blood is taken into consideration, then the value taken in measurement I is significantly the highest in relation to other measurements. Concentration of free fatty acids were increased (p > 0.002) after exercise and remained on the same level until the following day. The levels of insulin were significantly decreased, but growth hormone levels were increased. The exercise had no impact on testosterone concentration, whereas average blood concentration of leptin in the successive measurements showed a decreasing trend, although these changes are not statistically significant.Our observations provide the possibly full view of the physiologic reaction to the applied program of complex physical exercise accompanied by music, supporting the exercise's rhythm. The research program presented requires further investigation, e.g., what is the recommended frequency of the exercises applied on a weekly basis, and when should the intensity of the same increase.

Introduction. The aim of the study was to assess the influence of an 8-week endurance training program on the functional status of the respiratory muscles and breathing efficiency. Material and methods. Thirteen healthy, untrained, male students of Physical Education volunteered to participate in the study. Before and after the subjects completed the training program, they were subjected to anthropometric and spirometric measurements, and performed an incremental stress test. The spirometric measurements included maximal inspiratory pressure (PImax), active time, passive time, and diaphragm relaxation time. Measuring PImax is a simple method of evaluating the strength of the inspiratory muscles. The 8-week training program was performed on a rowing ergometer 3 times per week, using aerobic workloads. Results. The study did not confirm a significant improvement in the measured spirometric parameters following the training program. However, we observed a trend of increase in PImax values by 12 ± 21% of borderline after the training program and a significant correlation (p < 0.05) between the changes in PImax and those in VO2 max. Following the training there was also a significant reduction in the amount of body fat by 1.4 kg and an improvement of work capacity. The response of the respiratory system to exercise was also enhanced, as breathing efficiency improved (tidal volume increased in maximal exercise, while lung ventilation, the ventilatory equivalent for oxygen, and breathing frequency decreased in submaximal exercise). Conclusions. The findings of the study suggest that traditional endurance training which is implemented over a 8 weeks is not a sufficiently strong stimulus to cause a significant increase in the strength of the inspiratory muscles.

Introduction. The aim of the study is to evaluate the metabolic and hormonal response of soccer players to maximum effort (test for determining anaerobic threshold changes -PPA) carried out under field conditions within a training cycle, which included a preparation period of about 7 weeks. Materials and methods. In blood samples of the 20 subjects the concentrations of lactate was determined, (LA) in whole blood, also including cortisol (C), testosterone (T) and growth hormone (GH) in blood plasma, during a running exercise performed according to the formula for determination of PPA. The heart rate (HR) was recorded during the running exercise. Threshold speed was determined based on OBLA. The tests were carried out twice: at the beginning and at the end of the seventh week preparatory period. Results. The training increased the threshold speed by an average of 0.4 m/s, lower concentrations of LA during the second test and less severe changes in HR. Endurance of the tested athletes increased at more favourable hormonal response with respect to cortisol nd and GH. The endurance component in the training, in the 2 test resulted in lower resting testosterone levels, which did not affect the metabolic balance. The ratio of testosterone to cortisol (T/C), its growth after the period of training, showed a more stable anabolic-catabolic balance, which justifies the validity of the training assumptions in this period. Conclusions. The study confirmed the usefulness of metabolic-endocrine indicators in the monitoring the physiological response of athletes to exercise, as well as beneficial changes in the process of adaptation of bodies of athletes subjected to training.