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T Vuorimaa

Publications and source records attributed to T Vuorimaa.

12 recordsLinked to original sources
PubMed2000

Comparison of physiological strain and muscular performance of athletes during two intermittent running exercises at the velocity associated with VO2max.

The purpose of this study was to examine physiological strain and muscular performance responses of well trained athletes during two intermittent running exercise protocols at the velocity associated with VO2max. Ten national level middle-distance runners (VO2max 69.4+/-5.1; mean+/-SD) performed in random order two 28 min treadmill running exercises: 14 bouts of 60 s runs with 60 s rest (IR60) and 7 bouts of 120 s runs with 120 s rest between each run (IR120). During IR120 peak oxygen uptake (12%), peak heart rate (3%) and peak blood lactate (79%) were significantly higher than during IR60 (P< 0.001) and almost the same as in the VO2max test. In IR120 the relative aerobic energy release calculated on the basis of the accumulated oxygen deficit during the running bouts was significantly higher than in IR60 (81.5+/-2.7 vs. 70.2+/-2.6%, P<0.001) likewise the sum oxygen consumption during the 14 min running (P< 0.001), while during the 14 min recovery it was as much lower (P < 0.001). There were no changes either during or between the IR60 and IR120 protocols with regard to the muscular performance parameters, stride length or height of maximal vertical jumps. In conclusion, during intermittent running at the velocity associated with VO2max doubling the duration of work and rest bouts from 60 s to 120s increased the physiological strain of well trained athletes to the same level as at exhaustion in the VO2max test but the muscular performance variables were not influenced.

Adult↗
PubMed1997

Effects of acute prolonged exercise on-serum and LDL oxidation and antioxidant defences.

We investigated the acute effects of long-distance running on oxidation of lipids and antioxidant functions in LDL and serum. Eight trained male runners who participated in a 31-km run and 22 male keep-fit runners who participated in a marathon run were enrolled into the study. Venous blood samples were taken before and immediately after the exercise. There were no changes in LDL diene conjugation (LDL-DC) or LDL antioxidant potential (LDL-TRAP) during the exercises. Serum (S-) TRAP and S-alpha-tocopherol rose during the 31-km run (by 22%, p = .0005, and by 29%, p = .011, respectively), and during the marathon (by 16%, p = .0014, and by 7%, p = .031, respectively). S-DC rose during the 31-km run (by 9%, p = .0026), but not during the marathon (p = .14). Preexercise and postexercise S-alpha-tocopherol correlated positively with pre and postexercise S-TRAP in the marathon run (r = .473, 95% CI 0.064 to 0.746, and r = .524, 95% CI 0.131 to 0.774, respectively). Thus, the paradoxical exercise-associated increase in S-TRAP is, at least in part, explained by a simultaneous rise in S-alpha-tocopherol concentration. However, acute exercise does not change LDL-DC or LDL-TRAP concentrations.

Adult↗
PubMed1997

Increased serum and low-density-lipoprotein antioxidant potential after antioxidant supplementation in endurance athletes.

We studied the effect of antioxidant supplementation on acute exercise-induced lipid peroxidation and antioxidant potential measured in serum and low-density-lipoprotein (LDL) samples. Eight endurance athletes repeated a 31-km running exercise twice with an interval of 4 wk. During the 4 wk before the runs, the subjects took in a single-blind randomized order either a combination of antioxidant supplements (the antioxidant trial; 294 mg vitamin E, 1000 mg vitamin C, and 60 mg ubiquinone daily) or placebo (the placebo trial). Venous blood samples were taken before and immediately after the 31-km run in both trials. Antioxidant supplementation raised the LDL antioxidant potential (TRAP) (40% and 30%, P = 0.0031), serum TRAP (9% and 10%, P = 0.0037), and serum alpha-tocopherol concentration (by 59% and 66%, P = 0.0004) in both pre- and postexercise samples, respectively. The supplementation did not, however, affect the concentration of LDL diene conjugation (DC) or of serum DC. Physical exercise increased serum DC (by 18% and 10%, P = 0.0004) but not LDL-DC, and the quantity of the increment of serum DC was not affected by antioxidant intervention. The major cause for the increased LDL-TRAP and serum TRAP after antioxidant supplementation is apparently the elevation of the serum alpha-tocopherol concentration.

Adult↗
PubMed1996

Comparison of three maximal anaerobic running test protocols in marathon runners, middle-distance runners and sprinters.

Three modifications of the maximal anaerobic running test (MART) were compared in sprinters (Spr, n = 5), middle-distance runners (Mid, n = 5) and marathon runners (Mar, n = 6). The MART1, MART3 and MART5 consisted of n sets of 1.20-s, 3.20-s and 5.20-s runs, respectively, on a treadmill with 40-s recovery between the runs and 100-s recovery between the sets. In each MART the velocity of the first set of runs was 3.0 m.s-1 and the slope 4 degrees. Thereafter, the velocity was gradually increased by 0.38 m.s-1 for each consecutive set until exhaustion. After each set and after exhaustion fingertip blood samples were taken to determine lactate concentration and three counter-movement jumps (CMJ) were performed. Maximal (Pmax) and submaximal (P4mM) running power in each MART was expressed as the oxygen demand (ml.kg-1.min-1) of the runs. In MART1, Mar had a significantly lower Pmax than Mid or Spr (mean +/- SD; 97.8 +/- 5.4 vs. 121.0 +/- 4.4 vs. 119.2 +/- 5.4 ml.kg-1.min-1), while in MART3 the groups did not differ significantly, and the sprinters were unable to perform MART5. Mar, Mid and Spr attained the lower Pmax the more runs per set in MART (p < 0.01). Mar had the higher peak blood lactate the more runs each set consisted of (p < 0.001). In Mid and Spr, the peak blood lactate did not differ significantly between the MARTs but was significantly higher than the corresponding peak blood lactate of the marathon runners. Pmax in MART1 correlated positively with maximal 20-m sprinting speed on a track and with CMJ height (p < 0.001, n = 16) but negatively with VO2 max (p < 0.001, n = 16) while in MART3 no significant correlations were found. It was concluded that the n.1.20-s protocol should be used to measure the maximal anaerobic power of all runners. However, in long-distance runners more runs per set may be needed to evaluate their anaerobic capacity.

Adult↗
PubMed1993

Lack of association between indices of vitamin B1, B2, and B6 status and exercise-induced blood lactate in young adults.

By means of a 5-week vitamin B-complex supplementation, associations between indices of vitamin B1, B2, and B6 status (activation coefficients [AC] for erythrocyte transketolase, glutathione reductase, and aspartate aminotransferase) and exercise-induced blood lactate concentration were studied. Subjects, 42 physically active college students (18-32 yrs), were randomized into vitamin (n = 22) and placebo (n = 20) groups. Before the supplementation there were no differences in ACs or basal enzyme activities between the groups. The ACs were relatively high, suggesting marginal vitamin status. In the vitamin group, all three ACs were lower (p < 0.0001) after supplementation: transketolase decreased from 1.16 (1.14-1.18) (mean and 95% confidence interval) to 1.08 (1.06-1.10); glutathione reductase decreased from 1.33 (1.28-1.39) to 1.14 (1.11-1.17); and aspartate aminotransferase decreased from 2.04 (1.94-2.14) to 1.73 (1.67-1.80). No changes were found after placebo. Despite improved indices of vitamin status, supplementation did not affect exercise-induced blood lactate concentration. Hence no association was found between ACs and blood lactate. It seems that marginally high ACs do not necessarily predict altered lactate metabolism.

Adolescent↗
PubMed1992

Changes in force production, blood lactate and EMG activity in the 400-m sprint.

The neural activation (iEMG) and selected stride characteristics of six male sprinters were studied for 100-, 200-, 300- and 400-m experimental sprints, which were run according to the velocity in the 400 m. Blood lactate (BLa) was analysed and drop jumps were performed with EMG registration at rest and after each sprint. Running velocity (P less than 0.001) and stride length (P less than 0.05) decreased and contact time increased (P less than 0.01) during the 400-m sprint. The increase in contact time was greatest immediately after runs of 100 and 300 m. The peak BLa increased and the rate of BLa accumulation decreased with running distance (P less than 0.001). The height of rise of the centre of mass in the drop jumps was smaller immediately after the 300 m (P less than 0.05) and the 400 m (P less than 0.01) than at rest, and it correlated negatively with peak BLa (r = -0.77, P less than 0.001). The EMG and EMG:running velocity ratio increased with running distance. It was concluded that force generation of the leg muscles had already begun to decrease during the first quarter of the 400-m sprint. The deteriorating force production was compensated for until about 200-300 m. Thereafter, it was impossible to compensate for fatigue and the speed of running dropped. According to this study, fatigue in the 400-m sprint among trained athletes is mainly due to processes within skeletal muscle rather than the central nervous system.

Adult↗
PubMed1990

Physiological performance capacity in different prepubescent athletic groups.

Endurance, strength and speed capacity were investigated among prepubescent male weight lifters (EL), endurance runners (ER) and sprint runners (SR). The subjects were selected by their coaches and all of them were classified as promising and successful junior athletes in the age groups of 10-13 years. Twelve boys belonged to athletic group (AG) and their performance capacity was compared to normally active control (C) boys (n = 9). Biological age was significantly (p less than 0.05) greater in AG (11.3 +/- 0.9 years) than in C (10.2 +/- 1.4 years) but in chronological age there was no difference between the groups. Maximal oxygen uptake was significantly (p less than 0.05) higher in AG (62.3 +/- 3.1 ml.kg-1.min-1) than in C (55.4 +/- 7.7 ml.kg-1.min-1). The endurance runners had the highest value (66.5 +/- 2.9 ml.kg-1.min-1). In anaerobic characteristics there were no significant differences. The rise of centre of gravity (0.26 +/- 0.03 m) of AG in a test for the best drop jump was clearly (p less than 0.05) higher than that (0.22 +/- 0.03 m) of C. The weight lifters and sprint runners were the best in the test for force production. AG had significantly (p less than 0.01) shorter choice reaction time (261 +/- 39 ms) than C (344 +/- 81 ms). Testosterone correlated with jump performances (p less than 0.05), biological age (p less than 0.01) and chronological age (p less than 0.001). Growth hormone correlated significantly only with biological age (p less than 0.05) and testosterone (p less than 0.001). In conclusion, endurance capacity (aerobic) and strength capacity were greater in the athletic group than in the control group and it was suggested that training background and more advanced biological maturation of the athletes affected especially their strength capacity. The parameters used in this investigation can be utilized for talent selection in sport.

Adolescent↗
PubMed1988

Heart rate and exercise intensity during sports activities. Practical application.

Variations in heart rate during exercise correlate with changes of exercise intensity and may be measured directly by radiotelemetry and continuous ECG recording. The heart rate can also be recorded in the memory of a microcomputer, which can be carried on the wrist as easily as a watch. The device has a transmitter and a receiver. By recording the heart rate during a training session or a segment of training, and calculating the average of the heart rate and comparing this average to both the maximum heart rate of the individual and his heart rate at rest, the relative heart rate to the intensity of the work load (% maximum heart rate) can be calculated. These results are useful in planning optimal training intensities for both the healthy and rehabilitating athlete. The use of target heart rate as a tool for exercise prescription is common. It represents the percentage difference between resting and maximum heart rate added to the resting heart rate. For calculating target heart rate there are also 2 other methods. The first represents the percentage of the maximum heart rate (%HRmax) calculated from zero to peak heart rate. The second represents the heart rate at a specified percentage of maximum MET (VO2max). An appropriate individual heart rate for each level of an endurance performance is best determined in the laboratory. This is carried out by increasing the speed of the runner in stages on a treadmill and by measuring the oxygen uptake, the lactic acid concentration in the blood and corresponding variations in the heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Electrocardiography↗
PubMed1977

A solid-phase radioimmunoassay for IgG and IgM antibodies against measles virus.

A solid-phase radioimmunoassay (RIA) was used to determine the presence of IgG and IgM antibodies to measles virus in human serum and cerebrospinal fluid (CSF). Purified measles virus was adsorbed on to polystyrene balls, which were then exposed to serial dilutions of test serum or CSF. The presence of antibody was measured by its capacity to bind 125I-labelled specific anti-human IgG or IgM. Serum from a variety of patients as well as measles-immune clinically healthy persons were tested; binding ratios (using negative human serum controls) were usually between 10 and 30, but with subacute sclerosing panencephalitis (SSPE) ratios were as high as 50. Of ten CSF specimens tested, all but one, which was taken early in the convalescent phase of measles infection, had detectable IgG antibody. In six patients with acute measles, IgM antibodies were found in all serum specimens taken one or more days after the onset of rash. Maximal titers of 1:10000 to 1:40000 were found about 7 days later. Thereafter, IgM titres decreased rapidly but were still detectable at 40 days. A purified ribonucleoprotein of measles virus was also used successfully as an antigen in this RIA method.

Antibodies, Viral↗
PubMedDate not supplied

Serum hormone and myocellular protein recovery after intermittent runs at the velocity associated with VO(2max).

The responses of serum myocellular proteins and hormones to exercise were studied in ten well-trained middle-distance runners [maximal oxygen consumption (VO(2max)) = 69.4 (5.1) ml x kg(-1) x min(-1)] during 3 recovery days and compared to various measures of physical performance. The purpose was to establish the duration of recovery from typical intermittent middle-distance running exercises. The subjects performed, in random, order two 28-min treadmill running exercises at a velocity associated with VO(2max): 14 bouts of 60-s runs with 60 s of rest between each run (IR(60)) and 7 bouts of 120-s runs with 120 s of rest between each run (IR(120)). Before the exercises (pre- exercise), 2 h after, and 1, 2 and 3 days after the exercises, the same series of measurements were performed, including those for serum levels of the myocellular proteins creatine kinase, myoglobin and carbonic anhydrase III (S-CK, S-Mb and S-CA III, respectively), serum hormones testosterone, Luteinizing hormone, follicle-stimulating hormone and cortisol (S-testosterone, S-LH, S-FSH and S-cortisol, respectively) and various performance parameters: maximal vertical jump height (CMJ) and stride length, heart rate and ratings of perceived exertion during an 8-min run at 15 km x h(-1) (SL(15 km x h(-1)), HR(15 km x h(-1)) and RPE(15 km x h(-1)), respectively). Two hours after the end of both exercise bouts the concentration of each measured serum protein had increased significantly (P < 0.001) compared to the pre-exercise level, but there were no changes in SL(15 km x h(-1)) or CMJ. During the recovery days only S-CK was significantly raised (P < 0.01), concomitant with a decrease in CMJ (P < 0.01) and an increase in RPE(15 km x h(-1)) (P < 0.01). Hormone levels remained unchanged compared to the pre-exercise levels during the recovery days and there were no significant differences between the two exercise bouts in any of the observed post-exercise day-to-day responses. With the exception of S-CK, after IR(120) the post-exercise responses returned to their pre-exercise levels within the 3 days of recovery. The present findings suggest that a single 28-min intermittent middle-distance running exercise does not induce changes in serum hormones of well-trained runners during recovery over 3 days, while changes in S-CK, CMJ and RPE(15 km x h(-1)) indicate that 2-3 days of light training may be needed before the recovery at muscle level is complete.

Adult↗
PubMedDate not supplied

Acute prolonged exercise reduces moderately oxidized LDL in healthy men.

We studied the effects of a 2-day walk exercise (6 h+6 h) on the serum concentration of circulating moderately oxidized LDL (LDL baseline conjugated dienes), lipids (total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride), antioxidants (alpha-tocopherol, gamma-tocopherol, beta-carotene, and ubiquinol-10), and antioxidant potential in serum (S-TRAP) and LDL (LDL-TRAP) in healthy well-trained men. The exercise was performed twice with an interval of 14 days. While 6 h walking the subjects drank 6 cl . kg (-1) water which contained either carbohydrate (CHO trial) or placebo (PLA trial). During the 2-day exercise the level of oxidized LDL decreased by 25 % (p=0.001) in the PLA trial. At the same time serum gamma-tocopherol decreased by 20 % (p=0.049), while the other measured antioxidants remained unchanged and the serum antioxidant potential increased by 22 % (p=0.018). Serum total cholesterol decreased by 3 % (p=0.017), serum triglycerides by 22 % (p=0.001), and LDL-cholesterol by 14 % (p=0.045). HDL cholesterol increased by 9 % (p=0.001). The results in the carbohydrate trial were similar to the ones in the PLA trial. The findings suggest that exercise of long duration but of low, non-exhaustive intensity decreases the concentration of circulating oxidized LDL simultaneously with an increase in serum antioxidant potential in healthy trained men. Carbohydrate ingestion during the exercise does not have any further effect on these changes.

Adult↗