Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation — Edge Hill University Skip to main navigation Skip to search Skip to main content Edge Hill University Home Help & FAQ Home Profiles Research Units Research output Projects Student theses Activities Prizes Impacts Datasets Search by expertise, name or affiliation Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation A. Sparks, N. Bridge, N. Cable, D. Doran, D. MacLaren Sport & Physical Activity Research output: Contribution to journal › Article (journal) › peer-review Overview Fingerprint Abstract Serum prolactin (PRL) concentrations become elevated following a low carbohydrate diet as well as exercise which elicits significant rises is core temperature. The effect of pre-exercise dietary manipulation on PRL responses to exercise, which significantly elevates core temperature, has not been scrutinised. Nine male subjects of mean (SD) age 28.6 (5.9) years, body mass 76.8 (8.5) kg, height 1.80 (0.7) m, and VO2max 4.8 (0.6) l.min-1 completed three laboratory simulated duathlon time trials consisting of a 5 km run, 30 km cycle, and a further 5 km run. Each time trial was separated by at least 1 one week. Subjects fasted overnight before the duathlons and were randomly given isoenergetic meals (3998 (2.2) kJ) 3.5 h before the start of exercise. The meals consisted of predominantly low carbohydrate (LCHO) or high carbohydrate (HCHO) macronutrient components, or a fasting (F) condition, in which subjects ate nothing. Rectal temperature was used as an index of core temperature (Tc). Venous blood samples were taken immediately prior to and following the final running stage, in order to determine serum prolactin responses. The analysis of PRL was performed using enzyme-linked immunosorbent assay. A general linear model ANOVA, with repeated measures was used to determine significant differences (P<0.05). Means were compared using the Bonferroni confidence interval. Relationships between variables were made using Persons correlation coefficient. PRL was unaffected prior to exercise by the meal strategies (P>0.05), but significant increases were observed following the completion of all the time trials (P<0.05). There were no significant differences in Tc as a result of the meal strategies, but the performance of the time trials caused significant increases in Tc (P<0.05). PRL was significantly correlated to Tc (r=0.81). Overall mean speed throughout the duathlons was used as an indicator of performance, but there were no significant differences as a result of the dietary conditions (6.6 (0.4) m s-1, 6.5 (0.4) m s-1, 6.4 (0.5) m s-1) for F, LCHO and HCHO, respectively (P>0.05). These data suggest that following acute dietary manipulation, the PRL response to strenuous exercise is unaffected, and post exercise elevations are likely to be a consequence of the rise in Tc. Original language English Journal The Journal of Physiology Volume 565P Publication status Published - 2005 Fingerprint Dive into the research topics of 'Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation'. Together they form a unique fingerprint. Prolactin Medicine & Life Sciences 100% Temperature Medicine & Life Sciences 58% Serum Medicine & Life Sciences 46% Meals Medicine & Life Sciences 36% Carbohydrates Medicine & Life Sciences 35% Carbohydrate-Restricted Diet Medicine & Life Sciences 29% Nutrients Medicine & Life Sciences 17% Fasting Medicine & Life Sciences 16% View full fingerprint Cite this APA Author BIBTEX Harvard Standard RIS Vancouver Sparks, A., Bridge, N., Cable, N., Doran, D., & MacLaren, D. (2005). Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation. The Journal of Physiology, 565P. Sparks, A. ; Bridge, N. ; Cable, N. et al. / Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation. In: The Journal of Physiology. 2005 ; Vol. 565P. @article{71addf5af66446048b342e229bf4031b, title = "Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation", abstract = "Serum prolactin (PRL) concentrations become elevated following a low carbohydrate diet as well as exercise which elicits significant rises is core temperature. The effect of pre-exercise dietary manipulation on PRL responses to exercise, which significantly elevates core temperature, has not been scrutinised. Nine male subjects of mean (SD) age 28.6 (5.9) years, body mass 76.8 (8.5) kg, height 1.80 (0.7) m, and VO2max 4.8 (0.6) l.min-1 completed three laboratory simulated duathlon time trials consisting of a 5 km run, 30 km cycle, and a further 5 km run. Each time trial was separated by at least 1 one week. Subjects fasted overnight before the duathlons and were randomly given isoenergetic meals (3998 (2.2) kJ) 3.5 h before the start of exercise. The meals consisted of predominantly low carbohydrate (LCHO) or high carbohydrate (HCHO) macronutrient components, or a fasting (F) condition, in which subjects ate nothing. Rectal temperature was used as an index of core temperature (Tc). Venous blood samples were taken immediately prior to and following the final running stage, in order to determine serum prolactin responses. The analysis of PRL was performed using enzyme-linked immunosorbent assay. A general linear model ANOVA, with repeated measures was used to determine significant differences (P<0.05). Means were compared using the Bonferroni confidence interval. Relationships between variables were made using Persons correlation coefficient. PRL was unaffected prior to exercise by the meal strategies (P>0.05), but significant increases were observed following the completion of all the time trials (P<0.05). There were no significant differences in Tc as a result of the meal strategies, but the performance of the time trials caused significant increases in Tc (P<0.05). PRL was significantly correlated to Tc (r=0.81). Overall mean speed throughout the duathlons was used as an indicator of performance, but there were no significant differences as a result of the dietary conditions (6.6 (0.4) m s-1, 6.5 (0.4) m s-1, 6.4 (0.5) m s-1) for F, LCHO and HCHO, respectively (P>0.05). These data suggest that following acute dietary manipulation, the PRL response to strenuous exercise is unaffected, and post exercise elevations are likely to be a consequence of the rise in Tc.", author = "A. Sparks and N. Bridge and N. Cable and D. Doran and D. MacLaren", year = "2005", language = "English", volume = "565P", journal = "Journal of Physiology", issn = "0022-3751", publisher = "Wiley-Blackwell Publishing Ltd", } Sparks, A, Bridge, N, Cable, N, Doran, D & MacLaren, D 2005, 'Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation', The Journal of Physiology, vol. 565P. Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation. / Sparks, A.; Bridge, N.; Cable, N. et al. In: The Journal of Physiology, Vol. 565P, 2005. Research output: Contribution to journal › Article (journal) › peer-review TY - JOUR T1 - Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation AU - Sparks, A. AU - Bridge, N. AU - Cable, N. AU - Doran, D. AU - MacLaren, D. PY - 2005 Y1 - 2005 N2 - Serum prolactin (PRL) concentrations become elevated following a low carbohydrate diet as well as exercise which elicits significant rises is core temperature. The effect of pre-exercise dietary manipulation on PRL responses to exercise, which significantly elevates core temperature, has not been scrutinised. Nine male subjects of mean (SD) age 28.6 (5.9) years, body mass 76.8 (8.5) kg, height 1.80 (0.7) m, and VO2max 4.8 (0.6) l.min-1 completed three laboratory simulated duathlon time trials consisting of a 5 km run, 30 km cycle, and a further 5 km run. Each time trial was separated by at least 1 one week. Subjects fasted overnight before the duathlons and were randomly given isoenergetic meals (3998 (2.2) kJ) 3.5 h before the start of exercise. The meals consisted of predominantly low carbohydrate (LCHO) or high carbohydrate (HCHO) macronutrient components, or a fasting (F) condition, in which subjects ate nothing. Rectal temperature was used as an index of core temperature (Tc). Venous blood samples were taken immediately prior to and following the final running stage, in order to determine serum prolactin responses. The analysis of PRL was performed using enzyme-linked immunosorbent assay. A general linear model ANOVA, with repeated measures was used to determine significant differences (P<0.05). Means were compared using the Bonferroni confidence interval. Relationships between variables were made using Persons correlation coefficient. PRL was unaffected prior to exercise by the meal strategies (P>0.05), but significant increases were observed following the completion of all the time trials (P<0.05). There were no significant differences in Tc as a result of the meal strategies, but the performance of the time trials caused significant increases in Tc (P<0.05). PRL was significantly correlated to Tc (r=0.81). Overall mean speed throughout the duathlons was used as an indicator of performance, but there were no significant differences as a result of the dietary conditions (6.6 (0.4) m s-1, 6.5 (0.4) m s-1, 6.4 (0.5) m s-1) for F, LCHO and HCHO, respectively (P>0.05). These data suggest that following acute dietary manipulation, the PRL response to strenuous exercise is unaffected, and post exercise elevations are likely to be a consequence of the rise in Tc. AB - Serum prolactin (PRL) concentrations become elevated following a low carbohydrate diet as well as exercise which elicits significant rises is core temperature. The effect of pre-exercise dietary manipulation on PRL responses to exercise, which significantly elevates core temperature, has not been scrutinised. Nine male subjects of mean (SD) age 28.6 (5.9) years, body mass 76.8 (8.5) kg, height 1.80 (0.7) m, and VO2max 4.8 (0.6) l.min-1 completed three laboratory simulated duathlon time trials consisting of a 5 km run, 30 km cycle, and a further 5 km run. Each time trial was separated by at least 1 one week. Subjects fasted overnight before the duathlons and were randomly given isoenergetic meals (3998 (2.2) kJ) 3.5 h before the start of exercise. The meals consisted of predominantly low carbohydrate (LCHO) or high carbohydrate (HCHO) macronutrient components, or a fasting (F) condition, in which subjects ate nothing. Rectal temperature was used as an index of core temperature (Tc). Venous blood samples were taken immediately prior to and following the final running stage, in order to determine serum prolactin responses. The analysis of PRL was performed using enzyme-linked immunosorbent assay. A general linear model ANOVA, with repeated measures was used to determine significant differences (P<0.05). Means were compared using the Bonferroni confidence interval. Relationships between variables were made using Persons correlation coefficient. PRL was unaffected prior to exercise by the meal strategies (P>0.05), but significant increases were observed following the completion of all the time trials (P<0.05). There were no significant differences in Tc as a result of the meal strategies, but the performance of the time trials caused significant increases in Tc (P<0.05). PRL was significantly correlated to Tc (r=0.81). Overall mean speed throughout the duathlons was used as an indicator of performance, but there were no significant differences as a result of the dietary conditions (6.6 (0.4) m s-1, 6.5 (0.4) m s-1, 6.4 (0.5) m s-1) for F, LCHO and HCHO, respectively (P>0.05). These data suggest that following acute dietary manipulation, the PRL response to strenuous exercise is unaffected, and post exercise elevations are likely to be a consequence of the rise in Tc. M3 - Article (journal) VL - 565P JO - Journal of Physiology JF - Journal of Physiology SN - 0022-3751 ER - Sparks A, Bridge N, Cable N, Doran D, MacLaren D. Serum prolactin responses to duathlon performance following pre-exercise dietary manipulation. The Journal of Physiology. 2005;565P. Powered by Pure, Scopus & Elsevier Fingerprint Engine™ © 2022 Elsevier B.V. We use cookies to help provide and enhance our service and tailor content. 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