Soluble tumour necrosis factor receptor-1 (sTNFR1) levels are positively associated with exercise intensity in athletes after strenuous off-road cycling.

AIM: Strenuous exercise can enhance plasma levels of pro- and anti-inflammatory cytokines. Increases in plasma tumor necrosis factor-alpha (TNF-α) are followed rapidly by a rise in its natural inhibitors, soluble TNF receptors (sTNFRs). These inhibitors likely prevent an over-response to the cytokine. Aims of the present study were: 1) analyze plasma sTNFR1 at different time-points in response to a strenuous off-road cycling competition; 2) evaluate whether plasma levels of sTNFR1 correlate to increased blood lactate levels on completion of the exercise. METHODS: Eight trained off-road cyclists took part in this study and the data collection occurred during an official off-road race. Blood samples were collected pre-race, immediately post-race, and 1 h, 2 h and 24 h during the recovery period, for plasma sTNFR1 and blood lactate determination. RESULTS: Increase in sTNFR1 plasma levels were observed immediately post-race, 1 h and 2 h post-race (P<0.01), returning to baseline levels at the end of the recovery period (24 h). Significant correlation between plasma levels of sTNFR1 and blood lactate concentration were observed at the end of the race (r=0.925; P<0.001). CONCLUSION: An off-road cycling race stimulated an increase in plasma sTNFR1 and this anti-inflammatory molecule was positively correlated to blood lactate concentration. This result reinforces the view that exercise intensity influences the increase in plasma anti-inflammatory molecules.

Signs of overload after an intensified training.

This study investigated effects of a 9-week intensified aerobic training and 3-weeks of recovery on signs of overload in 9 healthy active young males. Blood and saliva samples were collected and psychological questionnaires were administered during baseline (T1), intermediate load (T2), maximal load (T3), and recovery (T4) periods. Maximal oxygen uptake increased and blood lactate concentration decreased in T3, while running time in a 3 000 m track field test was significantly shorter. No significant changes were found in hematocrit, haemoglobin concentration, white blood cell count, lactate dehydrogenase, transaminases, interleukin-6, tumour necrosis factor-α, myeloperoxidase and markers of oxidative stress in plasma, or salivary cortisol and testosterone. Increases in different negative affect scales and in the total mood disturbance score of the Profile of Mood States were observed during T3. Scores in the stress scales of the Recovery-Stress Questionnaire for Athletes and in the State Anxiety Scale of the State-Trait Anxiety Inventory also showed significant increases during T3. The lack of effects in biomarkers together with the changes observed in psychological assessment indicates that an intensified training can produce psychological disturbances prone to early overreaching development. Additionally, it seems that psychological parameters are sensitive markers to detect stress produced by load increases.

Effects of resistance training in multiple sclerosis.

This study examined the effects of an eight-week progressive resistance training on different strength manifestations, muscle mass and functionality in multiple sclerosis patients. Thirteen volunteered patients (average age 43 years; range 35-51) with a confirmed diagnosis by a neurologist and mild to moderate disability participated twice a week in an eight-week progressive resistance training program after an eight-week control period without training. Intensity ranged from 40-70% of their maximal voluntary contraction. Outcome assessments included magnetic resonance image of the right and left thighs, strength manifestations (maximal voluntary contraction, muscular endurance and power), and functionality by the Up and Go test. All outcome assessments remained unaltered during the eight-week control period. After the eight-week strength training period, isometric strength (+16%, p<0.01), muscular endurance (+84%; p<0.001), maximal power (+51%, p<0.001), muscular hypertrophy from slice 6/27 to slice 11/27 of both thighs (p<0.05), and functionality (p<0.001) improved significantly. Moderate resistance training programs can improve muscle function without injuries and can be a promising therapy to delay the functional deterioration in multiple sclerosis patients.

Early explosive force reduction associated with exercise-induced muscle damage.

This study was aimed to analyze the loss of muscle explosive force in the early phase of eccentric exercise-induced damage, and its possible relationships with muscle soreness and blood creatine kinase (CK) levels. Squat jump (SJ) and countermovement jump (CMJ) heights decreased in response to an eccentric exercise (120 eccentric actions of the knee extensors), with reductions that persisted at least for 24 h. The SJ/CMJ ratio was not significantly modified. Blood CK levels changed significantly over time and CK activity was significantly higher at 6 and at 24 h when compared to values obtained immediately after the eccentric exercise. Muscle soreness perceived at 6 h was slightly higher than that experienced just after finalizing the exercise and reached a clearly upper value at 24 h. A highly significant relationship between SJ and CMJ height loss was observed. CK activity at 24 h was significantly related to the SJ height loss at 6 h and to both the SJ height loss and the CMJ height loss immediately after the exercise. In summary, eccentric exercise induced a reduction in the explosive force generating capacity that affected in a similar way the pure concentric jump (SJ) and the jump eliciting the stretch-shortening cycle (CMJ). Results obtained suggest that CK activity is a better predictor of explosive force reduction than soreness, at least when values close to the peak are used.

Anaerobic energy provision does not limit Wingate exercise performance in endurance-trained cyclists.

The aim of this study was to evaluate the effects of severe acute hypoxia on exercise performance and metabolism during 30-s Wingate tests. Five endurance- (E) and five sprint- (S) trained track cyclists from the Spanish National Team performed 30-s Wingate tests in normoxia and hypoxia (inspired O(2) fraction = 0.10). Oxygen deficit was estimated from submaximal cycling economy tests by use of a nonlinear model. E cyclists showed higher maximal O(2) uptake than S (72 +/- 1 and 62 +/- 2 ml x kg(-1) x min(-1), P < 0.05). S cyclists achieved higher peak and mean power output, and 33% larger oxygen deficit than E (P < 0.05). During the Wingate test in normoxia, S relied more on anaerobic energy sources than E (P < 0.05); however, S showed a larger fatigue index in both conditions (P < 0.05). Compared with normoxia, hypoxia lowered O(2) uptake by 16% in E and S (P < 0.05). Peak power output, fatigue index, and exercise femoral vein blood lactate concentration were not altered by hypoxia in any group. Endurance cyclists, unlike S, maintained their mean power output in hypoxia by increasing their anaerobic energy production, as shown by 7% greater oxygen deficit and 11% higher postexercise lactate concentration. In conclusion, performance during 30-s Wingate tests in severe acute hypoxia is maintained or barely reduced owing to the enhancement of the anaerobic energy release. The effect of severe acute hypoxia on supramaximal exercise performance depends on training background.

Effects of long-distance running on serum bilirubin.

This study was undertaken to determine the effects of long-distance running on serum bilirubin fractions. Thirteen male ultramarathon runners participating in a 100-km race volunteered for the study. Venous blood samples were obtained shortly before and immediately after the race. Decreased serum haptoglobin levels (-66%) indicated the presence of hemolysis. After accounting for plasma-volume loss, significant post-race increases were found for creatine kinase (+20-fold), creatine kinase-MB (+252%), alanine aminotransferase (+42%), aspartate aminotransferase (+193%), gammaglutamyl transpeptidase (+56%), and glutamate dehydrogenase (+58%) serum activities, suggesting that running causes alterations of both muscle and liver tissues. Serum concentration of total bilirubin was significantly elevated (+106%) following the race, with changes corresponding to both unconjugated (+96%) and conjugated esters (+283%) of the pigment and significant increases in the ratio of esterified to total bilirubin. Our data show that long-distance running causes increases in the different serum bilirubin fractions which can be accounted for both hemolysis and hepatic disturbances.

Effects of oral contraceptives on fibrinolytic response to exercise.

In this study the influence of low-dose oral contraceptives (OC) on the different components of the fibrinolytic system before and immediately after maximal exercise was examined in a group of 18 moderately active women. Nine women using OC and nine control women performed a maximal effort treadmill protocol. Comparison of the resting parameters revealed higher plasma FbDP, plasminogen, alpha 2-antiplasmin and protein C concentrations, and lower PAI activity in the OC group. No differences were observed in plasma concentrations of t-PA antigen, t-PA activity, PAI antigen, antithrombin III, and protein S. Acute maximal exercise resulted in significant increases in t-PA antigen, t-PA activity, t-PA/PAI complexes, and FbDP in both groups of subjects, while PAI activity was reduced. No significant differences were found for the change in those parameters between control and OC users. Exercise induced no variation in any of the groups for PAI antigen, alpha 2-antiplasmin, plasminogen, protein C, or protein S. Our data suggest that changes in the fibrinolytic system induced by physical exercise are not affected by oral contraceptives.

Relationship of measures of leisure time physical activity to physical fitness indicators in Spanish adults.

BACKGROUND: The purpose of our study was to examine the association between estimates of energy expenditure obtained by the Minnesota Leisure Time Physical Activity questionnarie (LTPA) and physical fitness indicators. METHODS. PARTICIPANTS: An adaptation of the LTPA was assessed in a sample of Spanish population: male (n = 44) and female (n = 38). INTERVENTIONS: the LTPA 1 year recall questionnaire was administered twice with a 12-month interval and participants also responded monthly the Four Week Physical Activity History (FWH) questionnaire. MEASURES: test-retest reliability of the LTPA and the relationships between changes in V.O2max, percent body fat and leisure time physical activity were examined. RESULTS: Corresponding components of the LTPA and the FHW were highly correlated and scores in heavy leisure time activities and household chores showed a relatively low variance ratio, indicating an acceptable reliability of the questionnaire. Heavy intensity physical activity and household chores were highly related to V.O2max and there was a weaker association to moderate or light activity. CONCLUSIONS: Our results suggest that the Spanish version of the LTPA is a relatively valid and reliable measure of regular physical activity and a valid estimator of cardiorespiratory fitness in adults.

Effects of aerobic and anaerobic physical conditioning on fibrinolysis.

The effects of aerobic and anaerobic physical conditioning on fibrinolysis were studied before and immediately after physical exercise. Moderately active controls (group A) were compared with aerobically- (group B) or anaerobically-conditioned (group C) subjects. Comparison of the resting parameters revealed that FgDP were significantly higher in group B as a compared to groups A and C. FbDP did not significantly differ between groups B and C and were significantly lower in group A. t-PA antigen and PAI antigen did not significantly differ between the three groups, but t-PA activity was elevated and PAI activity and t-PA/PAI complexes were reduced in group B. Following a maximal exercise test on the treadmill both FbDP and FgDP were significantly increased in all groups, although values for FbDP in group B and values for FgDP in group C reached a higher level than in group A. t-PA antigen and t-PA activity were also increased in the three groups. PAI activity was significantly reduced in groups A and C. t-PA/PAI complexes were significantly enhanced in all cases, but increased to a lower degree in group B. These results indicate that both aerobic and anaerobic physical conditioning induce activation of the fibrinolytic system.

[Evolution of the prevalence of Mycobacterium tuberculosis infection in a penitentiary population on admission to prison from 1991 to 1996]. / Evolución de la prevalencia de la infección por Mycobacterium tuberculosis en una población reclusa al ingreso en prisión entre 1991 y 1996.

BACKGROUND: In Spanish prisons tuberculosis is a serious problem of public health. The analysis of temporal trends of tuberculous infection can show the effectiveness of interventions developed. PATIENTS, MATERIAL AND METHODS: All admissions in a prison between July 1991 and June 1996, without antecedents of chemotherapy or chemoprophylaxis, were included. We gathered sociodemographic variables as well as prison-related variables and HIV-risk factors. Tuberculin skin test was performed with 2 U of PPD RT-23 following the Spanish Consensus to Criterion of Tuberculous Infection. Statistic analysis was based on multivariate analysis (logistic regression). RESULTS: 37% of 1,459 prisoners analyzed were infected with M. tuberculosis. The tuberculous infection was more frequent among older prisoners (p < 0.001) and those with more time spent in prison (p < 0.001). Those with BCG-vaccination showed lesser levels of tuberculin reaction (p = 0.001). Temporal trends of tuberculous infection didn't show variations, but in intravenous drug users IVDU (p = 0.012) and those with time spent in prison (p = 0.08) it was increased. CONCLUSIONS: We detected a high prevalence of tuberculous infection and the time spent in prison was one of the risk factors. The infection was probably underestimate among those with BCG-vaccination because of the criterion used. The tuberculous infection was increased among IVDU and those with antecedent of time spent in prison.

The MnSOD Ala16Val SNP: relevance to human diseases and interaction with environmental factors.

The relevance of reactive oxygen species (ROS) production relies on the dual role shown by these molecules in aerobes. ROS are known to modulate several physiological phenomena, such as immune response and cell growth and differentiation; on the other hand, uncontrolled ROS production may cause important tissue and cell damage, such as deoxyribonucleic acid oxidation, lipid peroxidation, and protein carbonylation. The manganese superoxide dismutase (MnSOD) antioxidant enzyme affords the major defense against ROS within the mitochondria, which is considered the main ROS production locus in aerobes. Structural and/or functional single nucleotide polymorphisms (SNP) within the MnSOD encoding gene may be relevant for ROS detoxification. Specifically, the MnSOD Ala16Val SNP has been shown to alter the enzyme localization and mitochondrial transportation, affecting the redox status balance. Oxidative stress may contribute to the development of type 2 diabetes, cardiovascular diseases, various inflammatory conditions, or cancer. The Ala16Val MnSOD SNP has been associated with these and other chronic diseases; however, inconsistent findings between studies have made difficult drawing definitive conclusions. Environmental factors, such as dietary antioxidant intake and exercise have been shown to affect ROS metabolism through antioxidant enzyme regulation and may contribute to explain inconsistencies in the literature. Nevertheless, whether environmental factors may be associated to the Ala16Val genotypes in human diseases still needs to be clarified.

Sweat lactate, ammonia, and urea in rugby players.

The purpose of this study was to investigate sweat lactate, ammonia, and urea excretion in rugby players. Fifteen elite amateur rugby players volunteered to participate. The study was conducted during competitive matches in the official season. Plasma and sweat concentrations of lactate, ammonia, and urea were measured before and after the matches. Peak values for creatine kinase activity were observed 24 h after the match. There was no significant change between time points for blood lactate concentration but secretion rate per unit surface and time was significantly reduced after the match. Sweat ammonia concentration increased significantly during the match; values were significantly reduced after 24 h and still remained low at 72 h. Secretion rate was also reduced from 24 h. Urea concentration was significantly reduced at 48 h, while secretion rates decreased at 24 h and 48 h. Lactate in blood was significantly elevated during the match but not thereafter. Blood ammonia was significantly elevated during the match and did not differ from the resting values at 24 or 48 h. Urea in blood tended to decrease during the match, with a significant reduction at 24 h. Significant positive correlations were observed between blood and sweat concentrations for urea and ammonia but not for lactate. Sweat rate correlated positively with sweat lactate secretion. The fact that part of the ammonia formed during exercise is lost with sweat indicates the importance of the purine nucleotide cycle during rugby matches. Our data also confirm that sweat lactate concentration is not influenced by circulatory blood lactate in rugby players.

Changes in the fibrinolytic system associated with physical conditioning.

The effects of physical conditioning on plasma fibrinolytic activity were studied in two groups of subjects. Volunteers not engaged in any sport were compared with individuals having been subjected to aerobic conditioning (middle-distance runners, defined as men running more than 80 km per week). Plasma concentrations of the different components of the fibrinolytic system were evaluated before and immediately after a maximal effort treadmill protocol. Comparison of the resting parameters revealed that under basal conditions for plasma concentrations of plasminogen, fibrinogen, alpha 2-antiplasmin, protein C and protein S there were no differences between the two groups. Concentrations of the fibrin degradation products (FbDP) and fibrinogen degradation products (FgDP) were significantly higher in the runners than in the control group, indicating an increased fibrinolytic potential that seemed to be a consequence of the reduced formation of tissue plasminogen activator-plasminogen activator inhibitor (t-PA-PAI) complexes. Acute maximal exercise resulted in pronounced fibrinolysis, evidenced by the elevation of FbDP and FgDP concentrations, in both groups of subjects. The acceleration of the fibrinolytic activity was larger in conditioned individuals, which could be accounted for by a higher t-PA release and reduced formation of t-PA-PAI complexes when compared to the untrained subjects.

Secondary hypogammaglobilinemia after use of carbamazepine: case report and review.

Immunologic disorders related to anticonvulsant therapy have been described in the last three decades, including cellular and humoral alterations that result in recurrent infections; however, the physiopathologic mechanisms are not completely understood. This report describes a patient with complex partial epilepsy and hypogammaglobulinemia while in treatment with carbamazepine, with significant improvement in clinical signs and laboratory tests after substitution to sodium valproate. The authors stress the importance of clinical and laboratory evaluation of patients in continuous anticonvulsant therapy, including immunoglobulins levels and peripheral blood evaluations.