This study was aimed to investigate changes in blood markers of oxidative damage induced by short-term supramaximal anaerobic exercise and to determine whether oxidative stress was associated to activation of the redox-sensitive transcription factor nuclear factor-kappaB (NF-kappaB). Both a single Wingate test (WAnT) test and series of four WAnTs separated by 60 min rest intervals were carried out by eight professional cyclists. Leukocyte 8-OH-2-deoxyguanosine levels were significantly elevated 24 h after both exercise protocols. A significant decrease in blood reduced glutathione (GSH) concentration was observed immediately after and at 15, 60 and 120 min of the single WAnT, followed by a return to basal value after 24 h. This decrease was parallel to a significant increase of the oxidised/reduced glutathione (GSSG/GSH) ratio, to an activation of NF-kappaB and to a significant decrease in the protein level of its inhibitor IkappaB. GSH concentration and the GSSG/GSH ratio changed significantly for the first three of the WAnTs series and normalised thereafter. A significant activation of NF-kappaB and a decrease in the IkappaB protein level were also detected. We conclude that short-term supramaximal anaerobic exercise induces oxidative stress, as evidenced by non cumulative damage to macromolecules and changes in the glutathione status. Our data also indicate that high intensity anaerobic work gives rise to an activation of the transcription factor NF-kappaB accompanied by a degradation of IkappaB.

Crossover trial. To investigate the effects of whole-body vibration (WBV) on muscular activity and blood flow velocity after different vibration treatments in patients with spinal cord injury (SCI). Research Center on Physical Disability (Spain). Eight individuals with SCI received six 3-min WBV treatments depending on a combination of frequency (10, 20 or 30 Hz) and protocol (constant, that is, three consecutive minutes of WBV, or fragmented, that is, three sets of 1 min of WBV with 1 min of rest between the sets). Femoral artery blood flow velocity was registered at minutes 1, 2 and 3 of WBV, and at minutes 1 and 2 after the end of the stimulus. Electromyography activity (EMG) of vastus lateralis (VL) and vastus medialis (VM) was registered at baseline and during WBV. Peak blood velocity (PBV) increased after 1, 2 and 3 min of WBV. The 10 Hz frequency did not alter blood flow, whereas the 20 Hz frequency increased PBV after 2 and 3 min of WBV, and the 30 Hz frequency increased PBV after 1, 2 and 3 min of WBV and during the first minute after the end of the stimulus. No protocol effect was observed for blood parameters. EMG activity of VL and VM increased independently of the applied frequency or protocol. WBV is an effective method to increase leg blood flow and to activate muscle mass in SCI patients, and could be considered to be incorporated in their rehabilitation programs.

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.

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.