Polymorphisms in Genes Encoding VDR, CALCR and Antioxidant Enzymes as Predictors of Bone Tissue Condition in Young, Healthy Men.

The aim of the study was to assess significant predictors of bone mineral content (BMC) and bone mineral density (BMD) in a group of young, healthy men at the time of reaching peak bone mass. Regression analyses showed that age, BMI and practicing combat sports and team sports at a competitive level (trained vs. untrained group; TR vs. CON, respectively) were positive predictors of BMD/BMC values at various skeletal sites. In addition, genetic polymorphisms were among the predictors. In the whole population studied, at almost all measured skeletal sites, the SOD2 AG genotype proved to be a negative predictor of BMC, while the VDR FokI GG genotype was a negative predictor of BMD. In contrast, the CALCR AG genotype was a positive predictor of arm BMD. ANOVA analyses showed that, regarding SOD2 polymorphism, the TR group was responsible for the significant intergenotypic differences in BMC that were observed in the whole study population (i.e., lower BMC values of leg, trunk and whole body were observed in AG TR compared to AA TR). On the other hand, higher BMC at L1-L4 was observed in the SOD2 GG genotype of the TR group compared to in the same genotype of the CON group. For the FokI polymorphism, BMD at L1-L4 was higher in AG TR than in AG CON. In turn, the CALCR AA genotype in the TR group had higher arm BMD compared to the same genotype in the CON group. In conclusion, SOD2, VDR FokI and CALCR polymorphisms seem to affect the association of BMC/BMD values with training status. In general, at least within the VDR FokI and CALCR polymorphisms, less favorable genotypes in terms of BMD (i.e., FokI AG and CALCR AA) appear to be associated with a greater BMD response to sports training. This suggests that, in healthy men during the period of bone mass formation, sports training (combat and team sports) may attenuate the negative impact of genetic factors on bone tissue condition, possibly reducing the risk of osteoporosis in later age.

IL-6 and HSPA1A Gene Polymorphisms May Influence the Levels of the Inflammatory and Oxidative Stress Parameters and Their Response to a Chronic Swimming Training.

The aim of the study was to evaluate whether the most common polymorphisms in the IL-6 and HSP70 genes affect the circulating heat shock protein 70 (HSP70), as well as inflammatory and prooxidant-antioxidant parameters in healthy men undergoing chronic endurance training. The subjects were randomly assigned to a 12-week swimming training (ST group) or control group (CON). Fasting blood samples were collected pre- and post-study period to assessment: superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, serum levels of lipid hydroperoxides (LHs), tumor necrosis factor α (TNFα), and HSP70. Subjects were genotyped for IL-6-174G/C, HSPA1A + 190 G/C and HSPA1B + 1538 A/G single nucleotide polymorphisms (SNPs) by real-time PCR. After a 12-week study period, a decrease in TNFα, HSP70, and GPx was observed in the ST group, but not the CON group. IL-6 SNP affected serum TNFα levels (main effect of genotype). Higher TNFα levels (pre- and post-study period) was observed in CC CON than in other IL-6 genotypes of CON and ST groups. However, a post-training decrease in TNFα was observed in both GG and CC IL-6 genotypes of ST group. In turn, only GG IL-6 genotype of the ST group was related to a post-training decrease in HSP70 (main time and genotype interaction). Moreover, pre- and post-training LHs were lower in GG than GC/CC HSPA1A genotypes of the ST group (main genotype effect). In conclusion, polymorphisms within the IL-6 and HSPA1A genes seem to affect baseline levels of some inflammatory parameters and prooxidant-antioxidant status and/or their changes after chronic swimming training. However, the results should be confirmed in a study with a larger sample size, one that includes individuals with sedentary lifestyles.

Impact of climatic conditions projected at the World Cup in Qatar 2022 on repeated maximal efforts in soccer players.

This study aimed to investigate the relationship between the climatic conditions predicted for the 2022 FIFA World Cup in Qatar and the capacity for repeated maximum effort (RSA), of soccer players. Twenty-four semi-professional soccer players participated in the study. The exercise test consisted of ten 6-second maximal efforts on a cycloergometer. A 90-second passive rest interval was used. Mechanical parameters were recorded in each repetition, and biochemical parameters at rest and even repetitions. The test was performed in a Weiss Technik WK-26 climate chamber under two different conditions: (1) thermoneutral (TNC - 20.5 °C; 58.7% humidity); (2) predicted for the 2022 World Cup in Qatar (QSC - 28.5 ± 1.92 °C; 58.7 ± 8.64% humidity). Significantly higher mean maximum power values were recorded in the second repetition under QSC conditions (1731,8 ± 214,4 W) (p = 0.025). A significantly longer time to reach maximum power was also recorded under TNC conditions compared to QSC conditions in repetition 2 (1,32 ± 0,33 s), (1,05 ± 0,29 s) (p = 0.016) and 6 (1,41 ± 0,48 s), (1,17 ± 0,25) (p = 0.036). There was a significantly higher rate of power loss, between repetition 2 (p = 0.023) and 4 (p = 0.043) under QSC conditions, compared to TNC. Considering the biochemical parameters, a significantly higher pO2 concentration was registered under QSC conditions in the 10th repetition (p = 0.006). The ambient temperature during exercise should be taken into account to determine the anaerobic exercise capacity of the athletes. At higher temperatures, there is a greater capacity for maximal effort, in terms of maximal power achieved, but with a greater decrease in performance.

Survival Training Effects on Oxidative Stress and Muscle Damage Biomarkers of Naval Cadets.

INTRODUCTION: It is important for military commanders to know the extent of fatigue experienced by soldiers undergoing a long-term military training. This knowledge can enable them to determine the level of physical capabilities of soldiers. The present study aimed to evaluate changes in the level of chosen biochemical parameters in blood during the survival training of Polish Naval Academy cadets.METHODS: Participating voluntarily in the research study were 14 cadets. All subjects were men, ages 23.1 2.0 yr. During the 36-h survival training, the subjects were deprived of sleep. The following biochemical parameters were assessed in venous blood collected from the cadets: creatine kinase (CK) activity, concentration of lipid hydroperoxides (LOOHs), superoxide dismutase activity (SOD), and glutathione peroxidase activity (GPx).RESULTS: After 36 h of training a significant increase was observed in CK (from 183.1 up to 530.2 U L1), LOOHs (from 1.72 up to 3.74 mol L1), and GPx (from 27.4 up to 36.4 U gHb1). After 12 h of rest, the level of LOOHs returned to the initial level, GPx activity did not change significantly, and CK activity was significantly higher than those at baseline (422.3 U L1).DISCUSSION: The 36-h survival training increased oxidative stress, which contributed to the damage to muscle cells in the group of cadets of the Polish Naval Academy. The intensity of postexercise changes in the level of oxidative damage indicators is dependent on the initial level of enzymatic antioxidant defense. The 12-h recovery proved to be too short to regenerate the damaged muscle tissue.Tomczak A, Jwko E, Raski P. Survival training effects on oxidative stress and muscle damage biomarkers of naval cadets. Aerosp Med Hum Perform. 2020; 91(9):720724.

Assessment of the Levels of Oxidative Stress, Muscle Damage, and Psychomotor Abilities of Special Force Soldiers during Military Survival Training.

The aim of this study was to analyze the changes in biochemical markers of oxidative stress and muscle damage, as well as psychomotor abilities during a military survival training. The study included 15 soldiers of special unit (SU), that completed 48 h military survival training combined with sleep deprivation. Before the training (P1), after 24 h (P2), and after 48 h of training (P3), blood samples were taken to measure biochemical markers. At the same time points, the measurements of divided attention and handgrip strength were conducted. Glutathione peroxidase activity decreased significantly at P3, in comparison with P1 and P2 (p < 0.0001), however, no changes were observed in other biochemical markers (i.e., lipid hydroperoxides, creatine kinase and superoxide dismutase activity) throughout the survival training (p > 0.05). The divided attention index was improved significantly at P2 and P3, as compared to P1 (p < 0.05). A tendency to change in maximum strength was found during the training period (main time effect; p = 0.08). Moreover, the strength differentiation (i.e., 50% maximum strength; 50%max) was higher at P3 than at P1 and P2 (p < 0.05). In conclusion, the 48 h survival training in the SU soldiers does not cause oxidative stress or muscle tissue damage, as well as any deterioration, and even improvement in psychomotor abilities. However, the change in strength differentiation (i.e., the production above 60%max instead of target 50%max) after the training may point to deterioration in motor control. Although it should be confirmed in further study with a more numerous group of soldiers, our findings indicate that the special unit soldiers will be able to perform, in a correct manner, specialized tasks related to their long-term activities, especially those which require divided attention. However, participation in long-term survival training, even with low workload, combined with sleep deprivation, results in a deterioration in motor control which may indicate the relevance of monitoring coordination motor abilities/skills in the training process of special unit soldiers.

Gene polymorphisms and motor levodopa-induced complications in Parkinson's disease.

OBJECTIVE: The aim of the study was to evaluate the association of individual and combined single-nucleotide polymorphisms in brain-derived neurotrophic factor (BDNF), dopamine transporter (DAT), and catechol-O-methyltransferase (COMT) genes with the occurrence of motor levodopa-induced complications (MLIC) in Parkinson's disease (PD). MATERIALS AND METHODS: We studied 76 patients with PD (MLIC occurred in 56.6%) and 60 controls. Allelic discrimination of rs6265 BDNF (Val66Met), rs397595 DAT (SLC6A3), and rs4680 COMT (Val158Met) genes were genotyped. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using multinominal logistic regression. Orthogonal partial least squares (OPLS) analysis and OPLS discriminant analysis (OPLS-DA) were used to analyze qualitative genetic data. RESULTS: The risk of PD in subjects with the AG BDNF genotype was increased sixfold (OR = 6.12, 95% CI = 2.88-13.02, p < .0001), and AG BDNF and AG DAT genotypes were correlated with PD in OPLS-DA (VIP > 1). There were no differences in distributions of BDNF, DAT and COMT genotypes between PD groups with and without MLIC, while OPLS model showed that genotype combination of AG BDNF, AG DAT, and GG COMT was correlated with MLIC and genotypes combination of GG BDNF, AA DAT, and AA COMT with lack of MLIC in PD patients (VIP > 1). CONCLUSIONS: Our results confirmed the association of rs6265 BDNF (Val66Met) with the risk of PD and suggest a synergic effect of rs6265 BDNF (Val66Met), rs397595 DAT (SLC6A3), and rs4680 COMT (Val158Met) polymorphisms on the occurrence of MLIC.

Changes in Coordination Motor Abilities of Naval Academy Cadets During Military Survival Training.

INTRODUCTION: Armed conflicts tend to be unpredictable to such an extent that the fact that seamen also have to fight for their survival on land cannot be excluded. The aim of the study was to determine the degree of changes in selected coordination motor abilities in the course of a 36-h military survival training of Naval Academy cadets.METHODS: There were 14 Polish Naval Academy cadets, ages 20-27 yr, who were examined 4 times: pretraining, after 24 h, posttraining, and after a 12-h rest. Tests related to the following issues were carried out: divided attention, shooting performance, strength of forearm muscles and ability of its differentiations, body balance, and running motor adjustment. During the training soldiers had to perform the following tasks: first aid in the battlefield, building, water crossing to the enemy base, marching to the azimuth, operations in the recon team, and conducting observations.RESULTS: The maximum strength of forearm muscles during the training decreased from 7-10% during each and every measurement. The ability to differentiate the strength of the forearm muscles after the night part of the training deteriorated (about 9%). There was a systematic deterioration of the ability to maintain balance (between P1 and P4 by 24%).CONCLUSION: A 36-h training at a survival school varied the selected coordination motor abilities. Training should include exercises that develop an ability to differentiate muscle strength, motor adjustment, and balance. These exercises fall within the scope of coordination exercises that can be performed during obligatory physical education classes.Tomczak A, Rózanski P, Jówko E. Changes in coordination motor abilities of naval academy cadets during military survival training. Aerosp Med Hum Perform. 2019; 90(7):632-636.

The effect of low level laser irradiation on oxidative stress, muscle damage and function following neuromuscular electrical stimulation. A double blind, randomised, crossover trial.

BACKGROUND: Low level laser therapy (LLLT) is among novel methods for preventing and treating muscle damage and soreness induced by volitional exercise, but little is known about using LLLT before neuromuscular electrical stimulation. The aim of this first randomised, double blind, crossover trial addressing this issue was to evaluate effects of LLLT on muscle damage and oxidative stress, as well as recovery of muscle function after a single session of isometric neuromuscular electrical stimulation(NMES). METHODS: Twenty four moderately active, healthy men aged 21-22 years received 45 electrically evoked tetanic, isometric contractions of the quadriceps femoris, preceded by LLLT or sham-LLLT. Maximal isometric voluntary muscle torques, perceived soreness, and blood samples were analysed from baseline to 96 h post intervention. We measured plasma markers of muscle damage (the activity of creatine kinase), and inflammation (C-reactive protein), and evaluated redox state parameters. RESULTS: NMES-evoked contractions induced oxidative stress, demonstrated by an increase in lipid peroxidation and impairments in enzymatic antioxidant system. LLLT irradiations had a protective effect on NMES-induced decrease in enzymatic antioxidant defence and shortened the duration of inflammation. This effect of irradiations on redox state and inflammation did not affect lipid peroxidation, muscle damage, and muscle torque. CONCLUSIONS: LLLT may protect from impairments in enzymatic antioxidant system and may shorten inflammation induced by a single NMES session in moderately active, healthy men. However, the effects of LLLT on redox state and inflammatory processes do not seem to affect muscle damage and recovery of muscle function after NMES. TRIAL REGISTRATION: The study was retrospectively registered in the Australian New Zealand Clinical Trials Registry (ANZCTR); The trial registration number: ACTRN12619000678190; date of registration: 6 May 2019.

Effects of Rhodiola rosea supplementation on mental performance, physical capacity, and oxidative stress biomarkers in healthy men.

PURPOSE: The 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. METHODS: Twenty-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). RESULTS: R. 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. CONCLUSION: Chronic 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.

Effects of a 36-h Survival Training with Sleep Deprivation on Oxidative Stress and Muscle Damage Biomarkers in Young Healthy Men.

The aim of this study was to analyze changes in oxidative stress and muscle damage markers during a 36-h survival training combined with sleep deprivation. The study included 23 male students of physical education (specialty: Physical Education for Uniformed Services), randomly divided into the survival or control group. The students in the survival group completed a 36-h survival training with moderate to low physical activity, without the possibility to sleep. The students in the control group performed only physical activity included in daily routines and had a normal sleep pattern. No significant changes in measured parameters were seen in the control group throughout the study period. In the survival group, plasma lipid hydroperoxides (LHs) and creatine kinase (CK) activity increased at 24 h and remained elevated up to 36 h (main effects for LHs: time, p = 0.006 and group × time, p = 0.00008; main effects for CK: time, p = 0.000001, group, p = 0.005, and group × time, p = 0.000001). A 12-h recovery was sufficient to normalize both LHs and CK to the pre-training level; in fact, the post-recovery LHs and CK levels were even lower than at baseline. Residual total antioxidant capacity (TAC) of plasma (without the major constituents: uric acid and albumin) was elevated at both 24 h and 36 h of survival training, but not following a 12-h recovery (main effects: group, p = 0.001 and group × time, p = 0.04). In turn, the activity of glutathione peroxidase (GPx) in whole blood and superoxide dismutase (SOD) in erythrocytes decreased between 24 h and 36 h of survival training (main group effect for GPx, p = 0.038 and SOD, p = 0.045). In conclusion, these findings imply that a 36-h survival training with sleep deprivation impairs enzymatic antioxidant defense, increases lipid peroxidation, and induces muscle damage. Our findings also indicate that at least in the case of young physically active men, a 12-h recovery after the 36-h period of physical activity with sleep deprivation may be sufficient for the normalization of oxidative and muscle damage markers and restoration of blood prooxidant-antioxidant homeostasis.

SOD2 gene polymorphism may modulate biochemical responses to a 12-week swimming training.

The aim of the study was to analyze the effect of SOD2 Val16Ala polymorphism on blood biochemical response to chronic swimming training. Healthy men (students of physical education) participated in a swimming training program (ST group) or served as a control group (CON group). The swimming training program lasted 12 weeks (1.5h per day; 4 days per week). Fasting blood samples were obtained prior to (pre) and after (post) a 12-week study period, to measure the biomarkers of oxidative stress, muscle damage and lipid profile. No significant changes in the study parameters were documented in CON group after a 12-week study period, either overall or among carriers of specific SOD2 Val16Ala genotypes. In ST group, post-training decrease in serum lipid hydroperoxides (p < 0.05) and creatine kinase activity (p < 0.05) was associated with Ala/Ala genotype of SOD2 Val16Ala polymorphism. In turn, the increase in serum activity of superoxide dismutase (p < 0.05) was associated with Val carriers, and Val/Val genotype additionally predisposed to the post-training increase in total glutathione level in whole blood (p < 0.05). Moreover, in ST group, a 12-week swimming training program induced an increase in serum concentration of total cholesterol (p < 0.05), which resulted from an increase in both high density (p < 0.05) and low density lipoprotein cholesterol (p < 0.05). The change in high density lipoprotein cholesterol level was irrespective of the genotype. Also, a tendency to post-training increase in both total and low density lipoprotein cholesterol was observed in all three genotypes, although these changes were significant solely in Ala/Val genotype carriers (p < 0.05). In conclusion, 12-week swimming training induces changes in oxidative stress and muscle damage parameters, as well as in lipid profile. These changes seem to be associated with the presence of SOD2 Val16Ala polymorphism. Presence of Ala allele, especially as homozygote, is associated with some beneficial post-training changes, such as a decrease in lipid peroxidation and less pronounced muscle damage. In turn, the influence of SOD2 Val16Ala polymorphism on the changes in lipid profile in response to chronic swimming training should be verified in further study.

SOD2 gene polymorphism and response of oxidative stress parameters in young wrestlers to a three-month training.

The aim of the study was to analyse the effect of Val 16Ala polymorphism in SOD2 gene on oxidative stress parameters and lipid profile of the blood during a three-month wrestling training. The study included 53 Polish young wrestlers. Blood samples were collected at the beginning of the programme and following three months of the training. The list of analysed parameters included erythrocyte and serum activities of superoxide dismutase (SOD), whole blood glutathione peroxidase (GPx) activity, total glutathione (tGSH) level, concentration of lipid hydroperoxides (LHs), total antioxidant capacity (TAC) and creatine kinase (CK) activity in the serum, as well as lipid profile parameters: triglycerides (TG), total cholesterol (TC), high-density (HDL-C), and low-density lipoprotein cholesterol (LDL-C). Three-month training resulted in a decrease in CK activity, an increase in serum SOD activity, as well as in unfavourable changes in serum lipid profile: an increase in TC, LDL-C, and TG, and a decrease in HDL-C. Aside from CK activity, all these changes seemed to be associated with presence of Val allele. Prior to the training programme, subjects with Ala/Ala genotype presented with lower levels of LHs, lower whole blood GPx activity, and lower serum concentrations of TC than the individuals with Ala/Val genotype. Both prior to and after three-month training, higher levels of tGSH were observed in Val/Val genotype as compared to Ala/Val genotype carriers. Moreover, multiple regression analysis demonstrated that SOD2 genotype was a significant predictor of pre-training whole blood GPx activity and erythrocyte SOD activity (Val/Val > Ala/Val > Ala/Ala). Altogether, these findings suggest that Val 16Ala polymorphism in SOD2 gene contributes to individual variability in oxidative stress status and lipid profile of the blood in young wrestlers, and may modulate biochemical response to training.

The effect of green tea extract supplementation on exercise-induced oxidative stress parameters in male sprinters.

BACKGROUND: Although research suggests that antioxidant supplementation can protect against exercise-induced muscle damage and oxidative stress, also delayed post-exercise muscle recovery and hindered adaptation to training were reported in the supplemented athletes. PURPOSE: The purpose of the study was to evaluate the effects of green tea extract (GTE) supplementation on selected blood markers of oxidative stress and muscle damage in sprinters during preparatory phase of their training cycle. METHODS: Sixteen sprinters participated in a double-blind, randomized, placebo (PL)-controlled crossover study, including two 4-week treatment periods with PL and GTE (980 mg polyphenols daily). The sprinters performed two repeated cycle sprint tests (RST; 4 × 15 s, with 1-min rest intervals), after PL and GTE supplementation. Blood was sampled before (at rest), 5 min after RST, and after the 24-h recovery. The activities of superoxide dismutase (SOD) and glutathione peroxidase were measured in erythrocytes, and total polyphenols, total antioxidant capacity (TAC), uric acid (UA), albumin (AL), malondialdehyde (MDA), and creatine kinase (CK) were determined in blood plasma. RESULTS: Repeated cycle sprint test performed after PL induced an increase in MDA, TAC, and SOD. Moreover, an increase in UA, AL, and CK was observed after RST irrespective of experimental conditions (PL, GTE). Supplementation with GTE caused an increase in total polyphenols and TAC at rest, and a decrease in MDA and SOD after RST. No significant changes in sprint performance were noted after GTE, as compared to PL. CONCLUSIONS: Supplementation with GTE prevents oxidative stress induced by RST in sprinters. Furthermore, GTE supplementation does not seem to hinder training adaptation in antioxidant enzyme system. On the other hand, neither prevention of exercise-induced muscle damage, nor an improvement in sprint performance is noted after GTE administration.

Effect of a single dose of green tea polyphenols on the blood markers of exercise-induced oxidative stress in soccer players.

PURPOSE: To evaluate the effect of acute ingestion of green tea polyphenols (GTP) on blood markers of oxidative stress and muscle damage in soccer players exposed to intense exercise. METHODS: This randomized, double-blinded study was conducted on 16 players during a general preparation period, when all athletes participated in a strength-training program focused on the development of strength endurance. After ingestion of a single dose of GTP (640 mg) or placebo, all athletes performed an intense muscle-endurance test consisting of 3 sets of 2 strength exercises (bench press, back squat) performed to exhaustion, with a load at 60% 1-repetition maximum and 1-min rests between sets. Blood samples were collected preexercise, 5 min after the muscle-endurance test, and after 24 hr of recovery. Blood plasma was analyzed for the concentrations of thiobarbituric acid-reacting substances (TBARS), uric acid (UA), total catechins, total antioxidant status (TAS), and activity of creatine kinase (CK); at the same time, erythrocytes were assayed for the activity of superoxide dismutase (SOD). RESULTS: In both groups, plasma TBARS, UA, and TAS increased significantly postexercise and remained elevated after a 24-hr recovery period. SOD activity in erythrocytes did not change significantly in response to the muscle-endurance test, whereas in both groups plasma CK activity increased significantly after 24 hr of recovery. Acute intake of GTP cased a slight but significant increase in total plasma catechins. However, GTP was found not to exert a significant effect on measured parameters. CONCLUSIONS: Acute ingestion of GTP (640 mg) does not attenuate exercise-induced oxidative stress and muscle damage.

Green tea extract supplementation gives protection against exercise-induced oxidative damage in healthy men.

The purpose of this study was to evaluate the effects of a long-term (4-week) green tea extract (GTE) supplementation in combination with strength training on selected blood markers of oxidative stress and muscular damage after a short-term exercise in previously untrained men. We hypothesized that GTE supplementation would elevate antioxidant potential and attenuate exercise-induced oxidative stress and muscular damage. Thirty-five male students were exposed to 4 weeks of strength training and received (in a randomized, double-blind design) GTE (n = 17; 640 mg polyphenols/d) or placebo (P; n = 18). Before (term I) and after 4 weeks of strength training and supplementation (term II), students performed a short-term muscular endurance test. Blood samples were collected at rest, 5 minutes after the muscular endurance test, and after 24 hours of recovery. Supplementation with GTE enhanced plasma total polyphenols at rest and 5 minutes after the muscular endurance test. Supplementation also contributed to the rise of resting total antioxidant status in plasma. Throughout the experiment (terms I and II), a reduction in plasma lipid hydroxyperoxides was observed 24 hours after the muscular endurance test. Four weeks of strength training resulted in an increase in plasma lipid hydroxyperoxides at rest, but only in the P group. In term I, the muscular endurance test induced an increase in activity of creatine kinase in plasma after 24 hours of recovery in both the P and GTE groups. In term II, plasma creatine kinase activity after 24 hours of recovery was elevated only in the P group. In conclusion, in previously untrained men, dietary supplementation with GTE (in combination with strength training) enhances the antioxidant defense system in plasma at rest and, in turn, may give protection against oxidative damage induced by both short-term muscular endurance test and long-term strength training.

Hormonal and metabolic response in middle-aged women to moderate physical effort during aerobics.

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.