Pre-race Level Research Articles

Changes in hormone levels of participants in a 622-km ultramarathon race based on distance and recovery period.

Runners who participate in endurance sports such as marathons or ultramarathons have superior physical capabilities and health benefits compared to others. However, they may suffer long-term effects of the negative physiological changes during long-distance running. This study aimed to examine the effects of an ultramarathon on hormone levels, and the associated risks. Ten participants who completed a 622-km ultramarathon were included. Blood was collected prerace, at the 300-km mark, the 622-km mark, and on the 3rd day of recovery (RD3) and the 6th day of recovery (RD6) and analyzed for human growth hormone (HGH), cortisol, beta-endorphin, serotonin, testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels. HGH and beta-endorphin showed the highest increase at the 300-km mark compared to prerace levels, with recovery on RD3 and RD6, respectively. LH, cortisol, and serotonin showed the highest levels of increase at the 622-km mark, with recovery on RD6 for LH, and RD3 for cortisol and serotonin. FSH showed the highest level of decrease at both 300-km and 622-km marks compared to prerace levels, with recovery on RD3. Testosterone decreased the most at the 300-km mark compared to the prerace level and this decrease was below the normal levels; however, it recovered to normal levels on RD3. Hormone levels after the 622-km ultramarathon were within their normal ranges, except for testosterone. However, all the hormones recovered to prerace levels on RD3 or RD6. This study showed that running ultramarathons does not cause abnormal hormone levels.

Wheelchair half-marathon race increases natural killer cell activity in persons with cervical spinal cord injury

Non-randomized study. We reported that individuals with cervical spinal cord injury (CSCI) showed no increase in natural killer cell activity (NKCA) in response to 20-min arm exercise. It could be argued that this lack of response was owing to the short duration and intensity of the exercise. The 29th Oita International wheelchair marathon race. The present study compared the effects of wheelchair half-marathon race on natural killer (NK) cell count, NKCA and other hematological and hormonal parameters in six subjects with CSCI and seven control subjects with spinal cord injury between T4 and L1 (SCI), before, immediately after and 2 h after recovery. NK cell counts increased at both time points after the race in SCI, but not in CSCI, compared with before the race. NKCA increased immediately in both groups of subjects after the race, and then returned to the pre-race level at 2 h after the race. Plasma cortisol did not change in both groups throughout the study. Plasma adrenaline increased sharply in SCI after the race, then returned to the pre-race level at 2 h after the race, whereas no change was observed in CSCI throughout the study. The present study demonstrated that wheelchair half-marathon race increases NKCA despite the lack of increase in plasma adrenaline in CSCI, suggesting the activation of NKCA by mechanisms other than circulating adrenaline level.

Changes in serum cartilage oligomeric matrix protein (COMP), plasma CPK and plasma hs-CRP in relation to running distance in a marathon (42.195 km) and an ultra-marathon (200 km) race

Marathon running is frequently associated with numerous cellular changes, but little information is available on the effects of exercise-mediated prolonged impact-stress on cartilage integrity. This study was undertaken to evaluate muscle and cartilage damage with different running distances. Twenty male marathoners and ultra-marathoners participated in the study. Serum COMP and plasma CPK and hs-CRP were measured as markers of cartilage and muscle damage and inflammation. Serum COMP was increased 1.6-fold at 10 km during a marathon race and declined to the pre-race level after 2 days recovery. In contrast, serum COMP was increased 1.9-fold after a 200-km race and maintained until day 3 of recovery, only returning to the pre-race level on day 6. Plasma CPK was increased at 10 km of the marathon race and up to threefold at the end of the race. This was further increased on day 1, only returning to pre-race level on day 6. Plasma CPK was increased 35-fold at the end of the 200-km race and remained increased until day 5. There was no change in plasma hs-CRP during the marathon race, but this was increased 3.4-fold by day 1, returning to the pre-race level on day 4. Plasma hs-CRP increased 40-fold by the end of the 200-km race and was still increased on day 6 of recovery. Therefore, longer distance running may induce more impact-stress both on muscle and cartilage. Further, the required time for recovery may vary with running distance and the tissue type, e.g. cartilage or skeletal muscle as in this case.

Marathon running leads to partial exhaustion of ROS-generating capacity in leukocytes.

The aim of the present study was to investigate the changes occurring in leukocyte levels of reactive oxygen species (ROS) and total blood plasma antioxidant capacity (TAS) as a result of a marathon/half-marathon race. Fourteen men participating in the Oslo Marathon 2000 and 8 women and 8 men participating in the Oslo Half-Marathon 2001 were recruited to the study. Flow cytometry and the ROS-sensitive probe dihydroethidium (DHE) were used to study the intracellular levels of ROS in circulating leukocytes. Both basal ROS levels as well as the capacity of leukocytes to respond with ROS synthesis upon a defined in vitro stimulus, i.e., phorbol myristate acetate (PMA) was assessed before and immediately after the races. TAS was measured using the ABTS+ reduction assay kit. The basal levels of ROS in leukocytes were either not significantly changed (men, 3-25% reduced) or reduced 33% (women, P < 0.01) as a result of the marathon/half-marathon race. After the marathon race, the capacity of leukocytes to produce ROS upon PMA stimulation was reduced, i.e., 6% (granulocytes) (P < 0.001) and 23% (monocytes) (P < 0.01) residual capacity compared with the prerace situation. A 22-30% reduction (P < 0.05) in monocyte ROS response was seen also as a result of the half-marathon race, whereas the granulocyte ROS response was maintained at the prerace level (19% (women) and 15% (men) reduction, NS)). TAS increased significantly (11-19%, P < 0.05) after both races. The present results indicate an exhaustion of leukocyte ROS-generating mechanisms after prolonged strenuous exercise. This may partly explain the observation that athletes are more sensitive to attract infectious diseases if exposed to pathogenic micro-organisms during the immediate period after intensive physical activity.

Changes in cardiac autonomic regulation after prolonged maximal exercise.

Harmful cardiac events occurs frequently after exercise. However, the cardiac autonomic regulation after vigorous exercise is not well known. This study was designed to assess heart rate (HR) variability before and after a 75 km cross-country skiing race. HR variability was assessed by using standard statistical measures along with spectral and quantitative Poincarè plot analysis of HR variability in 10 healthy male subjects (age 36 +/- 11 years). The average HR was at the same level 1 day after the race as before the race, but on the second day, HR was significantly lower (P<0.001) compared with the prerace and 1 day after values. The normalized high-frequency (HF) spectral component of HR variability (nuHF) was lower (P<0.01) on the first day after the maximal exercise compared with the pre-exercise values but returned to or even exceeded the prerace level on the second day (P<0.01). The changes in short-term R-R interval variability analysed from the Poincaré plot were similar to those observed in the HF spectral component. The normalized low-frequency (LF) spectral component of HR variability (nuLF) was higher (P<0.01) on the first day after the exercise compared with the prerace levels and it also returned to the pre-exercise level or even dropped below it on the second day after the race. The mean time it took the HF spectral component to return to the pre-exercise level was 4.2 +/- 4.2 h (ranging from 0 to 12 h). This recovery time correlated inversely with the maximal oxygen consumption (VO2max) measured during the bicycle exercise test before the skiing race (r=-0.712, P<0.016). The cardiac vagal outflow is blunted for several hours after prolonged vigorous exercise. The recovery time of reduced vagal outflow depends on individual cardiorespiratory fitness and there is an accentuated rebound of altered autonomic regulation on the second day after prolonged exercise.

Magnesium metabolism after a full-marathon race

Japan Journal of Physical Fitness Sports Medicine; Volume 47:221-230, 1998 Abstract: We examined the relationship between serum magnesium (sMg) change and urinary Mg (uMg) excretion, lipid metabolism, and hormonal responses induced by prolonged physical exercise. Six recreational runners voluntary participated in the study, and their sMg uMg, serum lipid, and circulatory levels of plasma hormones (ACTH, cortisol, ADH, and aldosterone) were determined during a 1-wk recovery period after a full-marathon race. Immediately after the race, fall of sMg was significant but recovered to the prerace level in the next day. Urinary Mg excretion decreased significantly after the race, and the tubular reabsorption rate (%TRMg) was elevated for 1 wk. The negative correlation between sMg and %TRMg suggested that a decreased level of sMg enhanced tubular reabsorption of Mg. On the other hand, no correlation was observed between the plasma hormone levels and %TRMg; thus, hormonal responses induced by prolonged exercise had less effect on the tubular reabsorption of Mg. Therefore, fall of sMg after the full marathon race may not be a reflection of Mg depletion but seems to be the result of a Mg shift to other regions (muscle, erythrocytes, and adipose cells) from the serum. Increased level of serum FFA after the race suggested enhanced lipolysis, which might be a cause of sMg reduction.

Evidence of impaired left ventricular performance after an uninterrupted competitive 24 hour run.

The effect of extremely exhaustive exercise on left ventricular performance was studied echocardiographically in 13 experienced male ultramarathon runners who took part in a competitive 24 hr run, completing distances of 114 to 227 km. Although the left ventricular end-diastolic dimension (EDD) was reduced by 7% (54 +/- 5 to 50 +/- 7 mm; p less than .005), the end-systolic dimension (ESD) increased slightly (33 +/- 5 to 34 +/- 6 mm; NS). As a consequence, the stroke dimension (21 +/- 2 to 16 +/- 2 mm; p less than .005) and fractional shortening (38 +/- 5% to 32 +/- 5%; p less than .005) declined by 24% and 16%, respectively. The reduction in fractional shortening was related to delta ESD (r = -.66; p less than .05) but not to delta EDD (r = .22; NS). In spite of reduced afterload, the mean velocity of circumferential fiber shortening also decreased by an average of 9% (p less than .01) in proportion to the distance completed (r = -.69; p less than .01). The systolic blood pressure/ESD ratio was 21% lower after the race (4.2 +/- 0.9 to 3.3 +/- 0.6; p less than .005). Body weight loss was not related to any alterations in left ventricular dimensions or ejection phase indexes. The stroke dimension and ejection phase indexes continued to decline within the last 6 hr of the race but returned to the prerace level 2 to 3 days after the race. Total serum creatine kinase peaked at 3917 to 64740 U/liter (mean 27427) and its MB percentage peaked at 2% to 6%.(ABSTRACT TRUNCATED AT 250 WORDS)

High density lipoprotein cholesterol, total cholesterol and triglycerides in serum after a single exposure to prolonged heavy exercise.

Serum high density lipoprotein (HDL) cholesterol, total serum cholesterol and triglycerides were determined in twenty men before, immediately after, and 1, 2 and 4 days after a 70 km cross-country ski race. HDL cholesterol increased by 12% of the pre-race level immediately after the race, rose further to 17% above the initial level on the following day, and was still elevated 4 days after the race. LDL + VLDL cholesterol, however, showed a tendency to decrease immediately after the race and was reduced by 17% and 11% of the pre-race level on the following 2 days. Triglycerides were reduced by 30% of the initial level immediately after the race, were still low on the following day, but were restored to normal 2 days after the race. It is concluded that a single exposure to prolonged heavy exercise induces changes in the HDL metabolism, showing that the physical exercise per se plays an important role for the increased HDL level seen in well-trained athletes.

Biochemical changes in a 100 km run: Proteins in serum and urine

Eleven male subjects took part in a 100 km running competition. Alterations in the total plasma protein and in ten individual plasma protein concentrations in blood and urine were measured prior to the run, immediately after and after 1 day of recovery. Five individual proteins showed a 7-10%, and lysozyme a 40%, increase in the plasma after the run. On the contrary, the haptoglobin concentration fell to 40% of its pre-race level. None of these variations were correlated with the plasma volume change. The present data showed a moderate hemolysis, as evidenced by plasma lysozyme and hemoglobin-haptoglobin binding. The urinary excretion of plasma proteins was slightly increased, especially albumin and alpha1-acid-glycoprotein. The renal clearance of plasma proteins revealed that the 100 km run induced a moderate increase of glomerular permeability without any signficant change in the tubular reabsorption process.

Changes in plasma amino acid distribution and urine amino acids excretion during prolonged heavy exercise.

Venous plasma and urine amino acids and urea were measured in ten well-trained men, aged 23--45 years, in connection with a 70 km cross-country ski race, lasting 4.39--6.04 h, leading to slight dehydration. The estimated urea production rate during the race was of the order 7.6 mumol/min, kg b.wt, i.e. twice the rate for such men on ordinary protein intake, during ordinary activity, thus suggesting increased protein catabolism. The race led to a fall of the total plasma amino acid concentration to about 60% of the pre-race level. In particular, the branched chain amino acids (valine, iso-leucine, leucine) and alanine were markedly reduced, whereas the S-containing amino acids (taurine, cystine, methionine) and the aromatic (phenylalanine, tyrosine, trytophan, histidine) and glutamine/glutamate were increased, unchanged or only moderately reduced. It is concluded that prolonged heavy exercise is accompanied by increased protein catabolism and changes in the plasma amino acid concentrations similar to those observed during prolonged starvation, but differing from those seen at heavy exercise of less than 2 h duration or prolonged exercise of moderate intensity.

Serum thyroxine, triiodothyronine and thyroid stimulating hormone after prolonged heavy excerise

Serum thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone (TSH) was measured before, immediately after and on the following days after a 70 km cross-country ski race in two groups of ten well-trained men, one aged 21--29 years, taking 5.01--7.03 h, and one aged 51--57 years, taking 6.07--7.38 h. T4 was definitely increased immediately after the race, but fell to below the initial level on the following day and was not restored to the pre-race level until 4 days after the race. T3 showed essentially the same pattern, though less pronounced, a major part of the changes being possibly due to plasma volume variations. TSH showed a tendency to rise immediately after the race, but rose further to 175% of the initial level on the following day and was not restored to the initial level 4 days after the race. The pattern of changes were independent of age. It is suggested that the prolonged rise in TSH is probably due to an exercise-induced increased peripheral need for thyroid hormone.

Urea and creatinine production and excretion in urine during and after prolonged heavy exercise.

Serum and urine creatinine and urea were determined in well-trained men for several days in connection with three long-distance cross-country ski races (70–90 km). The races led to about 60 per cent increase in serum creatinine and urea, the return to the pre-race level being rapid for creatinine and taking several days for urea. The average race creatinine and urea production rates were about 60–80 per cent higher than under resting conditions, whereas the race urinary excretion was about the same as that at rest for creatinine but was markedly reduced for urea. The race urea production, the changes in serum urea and creatinine, as well as the time taken for the serum changes to return to pre-race levels rose with increasing age, whereas the race urine flow and clearance of urea and particularly of creatinine fell with age. One case, in which acute oliguric renal failure developed after a 90-km race, is included in an addendum to the report. It is concluded that the increase in serum creatinine after pro...