K. Kuoppasalmi

Plasma cortisol, androstenedione, testosterone and luteinizing hormone in running exercise of different intensities

Changes in plasma cortisol, androstenedione, testosterone and luteinizing hormone (LH) were measured in five young male sprinters after maximal short-term running and in five young male long-distance runners after moderate (90 min, 4.3 min/km) and intense (45 min, 3.3 min/km) long-term running. Short-term running increased mean plasma cortisol (27%) and androstenedione (19%) significantly; no appreciable changes were found in mean plasma testosterone or LH levels. Intense long-term running caused considerable increases in mean plasma cortisol (43%) and androstenedione (53%). Immediately after the long-term runs mean plasma testosterone and LH did not show nay significant changes, but half an hour later mean plasma LH was found to have dropped significantly below the preceding level, by 42% after the moderate run and by 45% after the intense run. At this time the intense long-term run caused a significant decrease in mean plasma testosterone, which remained depressed up to 3 h after the end of the exercise. This study implies that the changes in plasma hormone levels depend more on the intensity of the exercise than on its duration. The activity of the pituitary-adrenocortical system appears to be a good indicator of the effort expended during the exercise. In the pituitary-testicular system, in contrast, the effort expended may be more accurately reflected by changes during the recovery period.

Plasma cortisol, testosterone, androstenedione and luteinizing hormone (LH) in a non-competitive marathon run.

Abstract Plasma cortisol, testosterone, androstenedione and LH were determined in 14 men (27–58 years old) taking part in a non-competitive marathon (42.2 km). After the run the mean values showed a rise in cortisol and androstenedione and a fall in testosterone; these changes were statistically highly significant. After the marathon a significant correlation was found between the values for testosterone and androstenedione. Comparisons of the changes in cortisol, testosterone and androstenedione in relation to the control level show that significant correlations existed between the percentage increases in cortisol and androstenedione, and between the percentage decrease in testosterone and percentage increase in androstenedione. Plasma LH response varied, but the mean value after the run did not differ from the mean control value at the same time of day. One very fit subject, who ran the marathon in only 182 min, did not show any decrease in testosterone and his LH increased by more than 100%. One subject, who collapsed after running 15 km, had very low testosterone and LH values, although his cortisol value was unchanged as compared with his control value. The results suggest that during prolonged strenuous exercise LH and androgens, in addition to cortisol, play some role in promoting endurance in men.

Effect of strenuous anaerobic running exercise on plasma growth hormone, cortisol, luteinizing hormone, testosterone, androstenedione, estrone and estradiol

Abstract Plasma growth hormone (GH), cortisol, luteinizing hormone (lutropin, LH), testosterone, androstenedione, estrone and estradiol levels were investigated before and after strenuous anaerobic running exercise of short duration in five male runners. After the exercise there were statistically significant increases in the mean plasma concentrations of GH (233%), LH (49%), testosterone (13%) and androstenedione (34%). Plasma cortisol increased only slightly. The testosterone and androstenedione concentrations in the samples taken 6 h after exercise were below the control levels (51 and 40%, respectively). This effect was more pronounced than during the day of normal activity when in the same subjects the testosterone concentration decreased only 12%, and the androstenedione concentration did not change at all. Exercise affected plasma estradiol levels in the same way as it did testosterone and estrone levels in the same way as cortisol. Control values were not reattained for some of the hormones until more than 24 h after the run. In this study the most fit runner showed greater LH, testosterone, androstenedione and cortisol response than the least fit runner, who had a more elevated GH level after the run.

Plasma testosterone and sex-hormone-binding globulin capacity in physical exercise

Plasma testosterone (T) levels, sex-hormone-binding globulin (SHBG) capacities and T/SHBG ratios were measured in fifteen athletes during and after short- and long-term running exercises. Plasma SHBG did not change either during or after the running tests. In contrast, exercises of high intensity resulted in a slightly higher T/SHBG ratio during the exercise and a significantly lower T/SHBG ratio a few hours after the exercise. No difference in mean plasma SHBG capacity was found between trained and untrained men. This study indicates that increases or decreases in total plasma testosterone levels in exercise are associated with parallel changes in the free testosterone fraction.

High-energy phosphate compounds during exercise in human slow-twitch and fast-twitch muscle fibres

Concentrations of ATP and creatine phosphate, the high-energy phosphates, were investigated in slow-twitch (ST) and fast-twitch (FT) muscle fibres in sprinters and in long-distance runners at rest, during light sprinting exercise and during an extremely exhaustive running exercise. At rest the long-distance runners had significantly (P less than 0.005) more creatine phosphate in ST than in FT muscle fibres. Both the light and the exhaustive exercise induced breakdown of creatine phosphate to very low levels (10-15 mmol/kg; dry weight) in FT muscle fibres. In response to the exhaustive exercise, creatine phosphate in the ST fibres of the sprinters fell to a significantly (P less than 0.05) lower value than of the long-distance runners in the ST fibres. During the recovery period the synthesis of creatine phosphate seemed to be more rapid in FT than ST muscle fibres in light exercise (P less than 0.02) and in sprinters in exhaustive exercise (P less than 0.05). This study suggests that (1) during short-term exercise FT muscle fibres consume more of their creatine phosphate stores than ST muscle fibres, (2) in vigorous exercise athletes trained for sprinting are able to recruit not only the FT but also the ST muscle fibres, and (3) in such trained sprinters creatine phosphate is possibly resynthesized more rapidly in FT than in ST muscle fibres.

Plasma glucagon and catecholamines during exhaustive short-term exercise

SummaryPlasma glucagon and catecholamine levels were measured in male athletes before and after exhaustive 15 min continuous running and strenuous intermittent short-term exercise (3×300 m). Blood lactate levels were higher after the intermittent exercise (mean 16.7 mmol×l−1) than after the continuous running (mean 7.1 mmol×l−1). Plasma glucagon concentration increased during continuous running and intermittent exercise by 41% and 55%, respectively, and the increases in plasma noradrenaline concentration were 7.7- and 9.1-fold compared with the respective pre-exercise values. Immediately after the exercises plasma cyclic AMP, blood glucose and alanine levels were elevated significantly.The data suggest that the sympathoadrenal system is of major importance for liver glucose production during high-intensity exercises. Catecholamines directly stimulate liver glucose production and may indirectly stimulate it by enhancing the secretion of glucagon.

Pituitary and gonadal function during physical exercise in the male rat

The effects of training and acute exercise on serum testosterone, luteinizing hormone (LH) and corticosterone levels and on testicular endocrine function in male rats were studied. In the first part of the study, the rats were trained progressively on a treadmill, over 8 weeks. Training did not change the basal levels of serum testosterone, LH and corticosterone, or the testicular concentrations of testosterone and its precursors progesterone and androstenedione. The levels of testicular LH (30.3 +/- 2.6 ng/g wet wt, mean +/- SEM) and lactogen (150 +/- 14 pg/g) receptors were unchanged after training. However, the capacity of testicular interstitial cell suspensions to produce cAMP and testosterone increased by 20-30% during in vitro gonadotropin stimulation. In the second part, the trained and untrained control animals underwent acute exhaustive exercise. Serum testosterone levels decreased by 74 and 42% in trained and untrained rats, respectively (P less than 0.02), and corticosterone rose by 182% in trained and 146% in untrained rats (P less than 0.01), whereas the LH level was unchanged. Testicular levels of testosterone and its precursors decreased, with the exception of unchanged androstenedione, in trained rats; the cAMP concentration was unchanged. In both trained and untrained rats, acute exercise decreased the capacity of interstitial cell suspensions to produce cAMP, whereas there were no consistent effects on testosterone production. Acute exercise had no effect on LH or lactogen receptors in testis tissue. In conclusion, training had no effect on serum or testicular androgen concentrations, but increased Leydig cell capacity to produce testosterone and cAMP. Acute exercise decreased serum and testicular testosterone concentrations without affecting serum LH. A direct inhibitory effect of the increased serum corticosterone level on the hypothalamic-pituitary level and/or testis may be the explanation for this finding.

Plasma renin activity, angiotensin II, and aldosterone during the hypnotic suggestion of running

The plasma renin activity (PRA), angiotensin II and aldosterone concentrations, heart rate and blood pressure of four male athletes were measured before, during and after a hypnotically suggested run. While under hypnosis the test subjects were once again brought through a training exercise of 3 × 300 m sprints that they had run about one year earlier. This hypnotic ‘run’ caused changes in the renin-angiotensin-aldosterone (R-A-A) system of the athletes similar to but smaller than accused by the actual exercise. The maximal mean increase in PRA, found 30 min after the hypnotic ‘run’, was 26.7% (P<0.05) and that in plasma angiotensin II concentration 136% (P<0.05) when compared to the values before the ‘warming-up’ period. However, the hypnotic suggestions of running caused no significant increase in plasma aldosterone concentrations. ‘Running’ also caused a significant increase in the heart rate (37.9%; P<0.05) and systolic blood pressure (8.7%; P<002) and a decrease in diastolic blood pressure (12.1%; P<...