José G. Villa

Urinary Levels of 8-Hydroxydeoxyguanosine as a Marker of Oxidative Damage in Road Cycling

We have determined the urinary 8-hydroxydeoxyguanosine (8-OHdG) levels of eight professional cyclists during a 4-day and a 3-week stage races. Monitoring of heart rates was used to establish zones corresponding to different intensities of exercise. The urinary 8-OHdG excretion, expressed by body weight, increased significantly in the first day or the first week of each race, respectively, and did not show further increases thereafter. Maximum 8-OHdG levels were reached in parallel to longer times spent at high intensities of exercise. Urinary excretion of creatinine increased with exercise, and changes in 8-OHdG levels were not detected when corrected by creatinine excretion. Serum glutathione concentrations did not change significantly at any point during exercise. We conclude that road cycling courses with an oxidative damage to DNA, which is sustained as long as the exercise is repeated. Both adaptation of antioxidant defenses and a decreased capacity to maintain a high intensity of effort may contribute to explain the absence of progressive increases in 8-OHdG excretion. The results of this study also confirm that the correction procedure using the amount of creatinine excreted should not be used when studying effects of exercise on urinary 8-OHdG.

Changes in the fibrinolytic system associated with physical conditioning.

SummaryThe 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, α2-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.

Sitting time increases the overweight and obesity risk independently of walking time in elderly people from Spain.

INTRODUCTION Obesity, defined as an excess of total body fat, is a matter of concern all over the world, and its prevalence is still increasing among elderly people. OBJECTIVES To examine whether sedentary behaviour (hours sitting per day) is associated with higher risk of central obesity, overweight-obesity and overfat in a representative sample of non-institutionalized Spanish elderly population and if so, whether hours walking per day modified this association. STUDY DESIGN A cross-sectional study in a sample of 3136 people ≥65 years of age. MAIN OUTCOMES MEASURES Anthropometric measurements were obtained using standardized techniques and equipment. Active and sedentary behaviours were recorded by questionnaire. RESULTS For both men and women, the higher prevalence of overweight-obesity, central obesity and overfat was found in those who spent sitting more than 4h per day and walk less than 1h, compared with those who spent sitting less than 4h per day and walk more than 1h (all p<0.001, except for central obesity in women). In men, more than 4h sitting per day was associated with 1.7-fold higher odds of having central obesity compared with those sitting less than 4h per day (p<0.01). In women, this sedentary behaviour increased the risk of overweight-obesity and overfat by 1.5 and 1.4, respectively (p<0.01). Age or time spent walking did not significantly change these results. CONCLUSION Sitting time increases the risk of overweight-obesity and overfat in women and the risk of central obesity in men, independently of walking time.

Workload demands in professional multi-stage cycling races of varying duration

Objetive: To analyse and compare the workload exerted by professional cyclists in 5-day, 8-day and 21-day stage races (5-SR, 8-SR, 21-SR). Methods: The study subjects were 30 professional cyclists competing in 10 5-SR, 5 8-SR and 5 21-SR. Heart rate (HR) was measured during the races and categorised into three intensity zones: Z1 (below the ventilatory threshold (VT)), Z2 (between VT and the respiratory compensation threshold (RCT)) and Z3 (above RCT). The training impulse (TRIMP) was calculated by multiplying the sum of the time spent in each zone by 1, 2 and 3, respectively. Monotony (average TRIMP/SD) and strain (total TRIMP×monotony) were also calculated for each race type. Results: The average time spent in Z3 during each stage was significantly (p<0.05) higher for 5-SR (∼31 min) and 8-SR (∼28 min) than for 21-SR (∼14 min). Daily TRIMP values in 5-SR (∼400) and 8-SR (∼395) were also higher than in 21-SR (∼370). Monotony was similar across races (∼3) but strain was about three times higher for 21-SR than for 5-SR and 8-SR. Conclusions: The cyclists’ effort by stage was less for 21-SR than for 5-SR and 8-SR. Competition strain and monotony accumulated during longer races influence the choice of strategies adopted by cyclists. It is likely that the intensity of each stage is modulated by total race duration, with longer races averaging the lowest daily workload.

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.

Mutations in the hereditary haemochromatosis gene HFE in professional endurance athletes

Background: Hereditary haemochromatosis, a disease that affects iron metabolism, progresses with a greater or lesser tendency to induce iron overload, possibly leading to severe organ dysfunction. Most elite endurance athletes take iron supplements during their active sporting life, which could aggravate this condition. Objective: To determine the prevalence and discuss potential clinical implications of mutations of HFE (the gene responsible for hereditary haemochromatosis) in endurance athletes. Methods: Basal concentrations of iron, ferritin, and transferrin and transferrin saturation were determined in the period before competition in 65 highly trained athletes. Possible mutations in the HFE gene were evaluated in each subject by extracting genomic DNA from peripheral blood. The restriction enzymes SnaBI and BclI were used to detect the mutations 845G→A (C282Y) and 187C→G (H63D). Results: Our findings indicate a high prevalence of HFE gene mutations in this population (49.2%) compared with sedentary controls (33.5%). No association was detected in the athletes between mutations and blood iron markers. Conclusions: The findings support the need to assess regularly iron stores in elite endurance athletes.

Physical exercise and improvement of liver oxidative metabolism in the elderly.

Abstract Drug metabolizing capacity is generally reduced in the elderly, and physical exercise has been reported to increase drug oxidative metabolism. The purpose of this investigation was to study the effects of engagement in a program of regular physical exercise on the clearance and metabolite excretion of antipyrine, a marker of oxidative metabolism, in elderly subjects. The saliva clearance of antipyrine and the production clearances of antipyrine metabolites were studied in 37 elderly women (mean age 66 years). Subjects attended 60-min sessions three times a week for 12 weeks. Each session consisted of both aerobic (training of cardiorespiratory capacity) and nonaerobic (training of muscular strength/endurance and flexibility/coordination) exercises performed at 50–75% of maximum oxygen uptake. Antipyrine was administered orally and pharmacokinetic parameters were obtained from saliva and urine samples. After 3 months of participation in the exercise program, salivary antipyrine clearance was significantly increased by 17% mean (SEM) 0.42 (0.02) vs 0.36 (0.02) ml/min/kg; P < 0.05) and the half-life of antipyrine was significantly reduced by 18% (17.9 (1.1) vs 22.3 (1.3) h; P < 0.05). No significant change with exercise was observed in the renal clearance of antipyrine or in the norantipyrine formation clearance, but significant increases were found for hydroxymethylantipyrine [42 (5) vs 32 (4) μl/kg/min; P < 0.05; +31%] and 4-hydroxyantipyrine [243 (18) vs 194 (17) μl/kg/min; P < 0.05; +25%] formation clearances. These findings indicate that regular exercise leads to increased disposition of antipyrine in the elderly and that the main metabolic pathways of the compound are changed differentially.

Relationship Between the Talk Test and Ventilatory Thresholds in Well-Trained Cyclists

Abstract Rodríguez-Marroyo, JA, Villa, JG, García-López, J, and Foster, C. Relationship between the Talk Test and ventilatory thresholds in well-trained cyclists. J Strength Cond Res 27(7): 1942–1949, 2013—The aim of this study was to extend the range of populations where the Talk Test (TT) might be used as a marker of physiologic thresholds. Eighteen highly trained cyclists underwent 2 incremental tests. One test included measurement of respiratory gas exchange to determine the ventilatory (VT) and respiratory compensation thresholds (RCTs). On a separate day, a TT was performed using the same exercise protocol. During TT, subjects read a standard paragraph at the end of each stage. The first stage at which the cyclists could not talk comfortably and could definitely not talk were referred to as the equivocal (EQ) and the negative stages (NEG), respectively. There were no significant differences in workload, heart rate, lactate, and rating of perceived exertion between VT (3.7 ± 0.4 W·kg−1, 150 ± 10 b·min−1, 1.6 ± 0.3 mm·L−1, and 4.1 ± 1.4, respectively) vs. EQ (3.6 ± 0.4 W·kg−1, 148 ± 12 b·min−1, 1.3 ± 0.5 mm·L−1, and 3.8 ± 1.2, respectively) and RCT (5.3 ± 0.4 W·kg−1, 177 ± 7 b·min−1, 4.0 ± 0.9 mm·L−1, and 7.2 ± 1.0, respectively) vs. NEG (5.3 ± 0.5 W·kg−1, 176 ± 10 b·min−1, 4.2 ± 1.3 mm·L−1, and 6.8 ± 1.5, respectively). We found significant relationships (p < 0.01) between VT and EQ and RCT and NEG for workload (r = 0.86 and 0.94, respectively), heart rate (r = 0.79 and 0.92, respectively), and rating of perceived exertion (r = 0.79 and 0.88, respectively). In conclusion, the present study showed that the EQ and NEG stages of TT can be used as a simple and practical surrogate of the VT and RCT in highly trained cyclists.

The effect of physical conditioning on antipyrine clearance

The effects of physical conditioning on antipyrine clearance were studied in two groups of subjects. Healthy men not engaged in the systematic practice of any sport were compared with endurance runners (defined as men running >80 km/week). Studies were carried out at three different periods of the annual plan training at 4-month intervals. Antipyrine was administered orally and pharmacokinetic parameters were obtained from saliva samples by the multiple-sample method. Endurance performance, expressed in terms of the maximal oxygen uptake (V˙O2max), the ventilatory threshold and the 4-mM · l−1 lactate threshold (OBLA), was higher in trained than in control subjects at each of the three periods. Antipyrine clearance was also significantly elevated and antipyrine half-life reduced in runners during all periods. No significant difference in V˙O2max or antipyrine clearance was found between the various periods in either trained or control subjects. Both ventilatory threshold and OBLA increased significantly along the training period in conditioned subjects. Significant correlations were found between antipyrine clearance and V˙O2max, ventilatory threshold and OBLA. In summary, these results indicate an association between aerobic conditioning and increased hepatic oxidative metabolism of low-clearance drugs.

Exercise intensity and load during different races in youth and junior cyclists.

Rodríguez-Marroyo, JA, Pernía, R, Cejuela, R, García-López, J, Llopis, J, and Villa, JG. Exercise intensity and load during different races in youth and junior cyclists. J Strength Cond Res 25(2): 511-519, 2011-This study analyzed and compared the exercise intensity exerted by Youth and Junior cyclists in single-day and stage races. Heart rate was measured during the races and categorized according to 3 intensity zones: Z1 (below the ventilatory threshold [VT]), Z2 (between the VT and the respiratory compensation threshold [RCT]), and Z3 (above the RCT). The training impulse (TRIMP) was calculated by multiplying the sum of the time spent in each zone by 1, 2, and 3, respectively. Time spent in Z1, Z2, and daily TRIMP were significantly higher (p < 0.05) in Junior than in Youth in both single-day races (21.6 ± 1.9 min vs. 14.8 ± 1.6 min, 55.4 ± 2.3 min vs. 34.7 ± 1.9 min, and 257 ± 6 vs. 194 ± 6, respectively) and stage races (49.2 ± 3.4 min vs. 23.5 ± 4.7 min, 51.2 ± 2.6 min vs. 35.3 ± 3.7 min, and 201 ± 10 vs. 147 ± 7, respectively). In Youth and Junior, time and percentage time spent in Z3 and daily TRIMP were also significantly higher (p < 0.05) in single-day races (39.0 ± 1.9 min, 40.2 ± 1.9% and 225 ± 7) than in stage races (13.9 ± 1.8 min, 15.2 ± 1.8% and 174 ± 8). In conclusion, the present study showed that races in both Youth and Junior categories are highly demanding and that their intensity and exercise load are related to the total race duration.