This study examined the effects of equal anaerobic and aerobic total work outputs on the relationship between reproductive hormones in men. Nine subjects performed three randomized trials on separate days: (1) 1 h period of rest (control), (2) 1 h continuous aerobic exercise (65% VO2 max), and (3) 1 h intermittent anaerobic exercise (which included 2 min exercise periods at 110% VO2 max). The total work output of the aerobic and anaerobic trials were equated. For the 8 h after each experimental trial, blood samples were collected hourly and analysed for testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin and cortisol. Diet, physical activity and circadian influences were all controlled. Compared with the control, the aerobic and anaerobic trials significantly (P < 0.05) elevated testosterone, prolactin and cortisol; however, these changes were transient and returned to control levels within 1-2 h of recovery. Neither exercise produced significant (P > 0.05) changes from control for LH and FSH. The area under the hormonal response curves (AUC) was calculated for the 8-h recovery period. The testosterone and LH AUC results did not differ (P > 0.05) among the trials (the FSH AUC was not calculated). The prolactin AUC for the aerobic and anaerobic trials were greater (P < 0.01) than the control trial. The cortisol AUC for the anaerobic trial was greater than both the control and aerobic trials (P < 0.05), but the aerobic and control trials did not differ from one another.(ABSTRACT TRUNCATED AT 250 WORDS)

The aim of this study was to explore the effect of one bout of aerobic exercise on epinephrine, norepinephrine, cortisol, glucose, lactate, and free fatty acid (FFA) responses in breast cancer survivors and healthy controls. 9 female breast cancer survivors and 9 women without a history of cancer completed 30 min of cycle ergometry exercise at 60 % of VO2peak. Blood samples were taken pre-exercise, immediately post-exercise, and 2 h post-exercise from which plasma concentrations of study variables were measured. Immediately and 2 h post-exercise, increases were observed in epinephrine (control group only) norepinephrine (both groups), lactate (both groups), and FFA (both groups immediately post-exercise; breast cancer survivor group only at 2 h post-exercise) (p < 0.05). Cortisol decreased immediately and 2 h post-exercise in the control group while glucose decreased immediately post-exercise in the breast cancer survivor group (p < 0.05). In conclusion, breast cancer survivors appeared to display attenuated epinephrine, cortisol, and lactate responses while displaying larger magnitude changes in glucose and FFA responses compared to controls. These preliminary findings may have implications for the regulation of metabolism during exercise in breast cancer survivors.

This study examined the effects of military field operations (MFO) under different environmental conditions on anaerobic performance. US Marines were tested in the field under the following conditions: 1) noncold environment (NC; n = 30, 10-32 degrees C) and 2) cold environment (CO; n = 32, -2 to -22 degrees C). Subjects performed 30-s Wingate tests (WIN) pre- and immediately post-MFO to assess anaerobic performance. The MFO consisted of approximately 4.5 days of combat training maneuvers while carrying field equipment (packs and weapon, approximately 25 kg). WIN measures obtained were absolute and relative mean power (MP), 5-s peak power (PP), and fatigue index (% decline). Significant main effects (P less than 0.01) were observed for time (pre-post MFO). Reductions occurred in absolute MP [651.8 +/- 30.3 to 616.4 +/- 28.5 (SE) W] and PP (897.8 +/- 41.6 to 857.0 +/- 39.1 W); however, no effect on fatigue index was seen. Significant interaction effects (P less than 0.05) were observed in relative measures. Reductions (pre-post) in MP (NC = 8.64 +/- 0.16 to 8.37 +/- 0.14 W/kg; CO = 8.91 +/- 0.26 to 8.04 +/- 0.15 W/kg) and PP (NC = 11.80 +/- 0.24 to 11.61 +/- 0.33 W/kg; CO = 12.23 +/- 0.35 to 11.20 +/- 0.19 W/kg) were greater under CO than NC conditions. These changes were found despite significant (P less than 0.05) but comparable pre-post weight reductions in both CO and NC conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Kortizolis yra kortisteroidinis hormonas, kurį gamina antinksčių žievės zona fasciculata (pluoštinė zona) antinksčių liaukoje. Jis atlieka gyvybiškai svarbią mechanizmų gynybinę funkciją tada, kai tenka įveikti stresą, taip pat jis reguliuoja gliukozės kiekį kraujyje. Labai gaila, bet sporto srityje šio hormono veikla yra klaidingai suprantama. Pavyzdžiui, dažnai manoma, kad kortizolis neigiamai veikia mankštinantis, ir dėl šio hormono katabolinės prigimties, turint omeny baltymų kaitą, per treniruotes organizmas sunkiai adaptuojasi. Šio straipsnio tikslas — apžvelgti ir išsiaiškinti, kokias nepaprastai svarbias funkcijas kortizolis atlieka per treniruotes ir adaptacijos metu, taip pat bandyta paneigti keletą konkrečių klaidingų sampratų ir nuomonių, pateikiamų kai kuriuose literatūros šaltiniuose (ypač internete) apie endokrinines organizmo reakcijas treniruojantis.