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Endocrine response to an ultra-marathon in pre- and post-menopausal women.

Copeland JL, Verzosa ML - Biol Sport (2014)

Bottom Line: Total IGF-I decreased after the race (P < 0.01) and remained lower in recovery.Postmenopausal women had significantly lower estradiol at baseline, but there were no other group differences.Further research is needed to confirm the effect of these endocrine changes on health and performance.

View Article: PubMed Central - PubMed

Affiliation: Dept. of Kinesiology, University of Lethbridge, 4401 University Drive, Lethbridge AB, Canada.

ABSTRACT
Ultra-endurance competitions are becoming increasingly popular but there is limited research on female participants. The purpose of this study was to examine changes in estrogen and the IGF-I system in women after an ultra-marathon. Six pairs of pre- and post- menopausal women were matched for race finish times;mean finish time was 20 hours. Blood samples were drawn 24 hours before the race, at the finish, and 24 hours into recovery. Samples were analysed for estradiol, total IGF-I, IGFBP-1, and intact IGFBP-3. There was a significant increase in estradiol following the race in both groups (P < 0.05). Total IGF-I decreased after the race (P < 0.01) and remained lower in recovery. IGFBP-1 increased after the race (P < 0.001) but returned to pre-race levels after 24 hours, while intact IGFBP-3 was significantly lower post-race and in recovery (P < 0.001). Postmenopausal women had significantly lower estradiol at baseline, but there were no other group differences. These results demonstrate that among recreational female runners, an ultra-marathon is associated with IGF system changes that are consistent with an energy-deficient, catabolic state. Further research is needed to confirm the effect of these endocrine changes on health and performance.

No MeSH data available.


Related in: MedlinePlus

SERUM IGF-I (PANEL A), IGFBP-1 (PANEL B) AND INTACT IGFBP-3 (PANEL C) CONCENTRATIONS BEFORE, AFTER, AND 24 HOURS AFTER AN ULTRA-MARATHON IN PRE- AND POST-MENOPAUSAL WOMEN.Note:Data are expressed as means ± SEM. Black bars and pre-race values, dark grey bars are immediately post-race values and light grey bars are 24 hour recovery values.* Significantly greater than post-race (P < 0.01) and recovery (P < 0.05)† Significantly greater than pre-race and 24 hour recovery (P < 0.001)†† Significantly greater than post-race and 24 hour recovery (P < 0.01).& Significantly lower than corresponding value in pre-menopausal women (P < 0.05)
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Figure 0003: SERUM IGF-I (PANEL A), IGFBP-1 (PANEL B) AND INTACT IGFBP-3 (PANEL C) CONCENTRATIONS BEFORE, AFTER, AND 24 HOURS AFTER AN ULTRA-MARATHON IN PRE- AND POST-MENOPAUSAL WOMEN.Note:Data are expressed as means ± SEM. Black bars and pre-race values, dark grey bars are immediately post-race values and light grey bars are 24 hour recovery values.* Significantly greater than post-race (P < 0.01) and recovery (P < 0.05)† Significantly greater than pre-race and 24 hour recovery (P < 0.001)†† Significantly greater than post-race and 24 hour recovery (P < 0.01).& Significantly lower than corresponding value in pre-menopausal women (P < 0.05)

Mentions: Figure 3 shows the pre- and post-race concentrations of IGF-I, IGFBP-3, and IGFBP-1 in both groups. Circulating IGF-I decreased by 21% (-9.9% with plasma volume correction) after the race compared to pre-race values (P < 0.01) and remained significantly lower than pre-race concentrations after 24 hours of recovery (P < 0.05). There was no difference in IGF-I between groups, although there was a significant correlation between pre-race concentrations of estradiol and IGF-I (ρ = 0.685, P < 0.05) and a negative correlation between estradiol and IGFBP-1 (ρ= -0.678, P < 0.05). Circulating concentrations of IGFBP-1 increased substantially (∼700%;650% with plasma volume correction) after the race in both groups (P < 0.001) but had returned to pre-race levels after 24 hours of recovery. Before the race, intact IGFBP-3 was significantly higher in the pre-menopausal group compared to the post-menopausal group (Figure 3, P < 0.05). IGFBP-3 was significantly lower after the race in both groups (P < 0.001), with an average decrease of 48% (41% with plasma volume correction) and concentrations remained lower than pre-race concentrations after 24 hours of recovery (P < 0.001). The molar volume ratio of IGF-I to intact IGFBP-3 was significantly greater immediately after the race and 24 hours after the race compared to the pre-race ratio (P < 0.01), with no difference between groups (Figure 4). The group x time interaction was not statistically significant for any component of the IGF system.


Endocrine response to an ultra-marathon in pre- and post-menopausal women.

Copeland JL, Verzosa ML - Biol Sport (2014)

SERUM IGF-I (PANEL A), IGFBP-1 (PANEL B) AND INTACT IGFBP-3 (PANEL C) CONCENTRATIONS BEFORE, AFTER, AND 24 HOURS AFTER AN ULTRA-MARATHON IN PRE- AND POST-MENOPAUSAL WOMEN.Note:Data are expressed as means ± SEM. Black bars and pre-race values, dark grey bars are immediately post-race values and light grey bars are 24 hour recovery values.* Significantly greater than post-race (P < 0.01) and recovery (P < 0.05)† Significantly greater than pre-race and 24 hour recovery (P < 0.001)†† Significantly greater than post-race and 24 hour recovery (P < 0.01).& Significantly lower than corresponding value in pre-menopausal women (P < 0.05)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4042659&req=5

Figure 0003: SERUM IGF-I (PANEL A), IGFBP-1 (PANEL B) AND INTACT IGFBP-3 (PANEL C) CONCENTRATIONS BEFORE, AFTER, AND 24 HOURS AFTER AN ULTRA-MARATHON IN PRE- AND POST-MENOPAUSAL WOMEN.Note:Data are expressed as means ± SEM. Black bars and pre-race values, dark grey bars are immediately post-race values and light grey bars are 24 hour recovery values.* Significantly greater than post-race (P < 0.01) and recovery (P < 0.05)† Significantly greater than pre-race and 24 hour recovery (P < 0.001)†† Significantly greater than post-race and 24 hour recovery (P < 0.01).& Significantly lower than corresponding value in pre-menopausal women (P < 0.05)
Mentions: Figure 3 shows the pre- and post-race concentrations of IGF-I, IGFBP-3, and IGFBP-1 in both groups. Circulating IGF-I decreased by 21% (-9.9% with plasma volume correction) after the race compared to pre-race values (P < 0.01) and remained significantly lower than pre-race concentrations after 24 hours of recovery (P < 0.05). There was no difference in IGF-I between groups, although there was a significant correlation between pre-race concentrations of estradiol and IGF-I (ρ = 0.685, P < 0.05) and a negative correlation between estradiol and IGFBP-1 (ρ= -0.678, P < 0.05). Circulating concentrations of IGFBP-1 increased substantially (∼700%;650% with plasma volume correction) after the race in both groups (P < 0.001) but had returned to pre-race levels after 24 hours of recovery. Before the race, intact IGFBP-3 was significantly higher in the pre-menopausal group compared to the post-menopausal group (Figure 3, P < 0.05). IGFBP-3 was significantly lower after the race in both groups (P < 0.001), with an average decrease of 48% (41% with plasma volume correction) and concentrations remained lower than pre-race concentrations after 24 hours of recovery (P < 0.001). The molar volume ratio of IGF-I to intact IGFBP-3 was significantly greater immediately after the race and 24 hours after the race compared to the pre-race ratio (P < 0.01), with no difference between groups (Figure 4). The group x time interaction was not statistically significant for any component of the IGF system.

Bottom Line: Total IGF-I decreased after the race (P < 0.01) and remained lower in recovery.Postmenopausal women had significantly lower estradiol at baseline, but there were no other group differences.Further research is needed to confirm the effect of these endocrine changes on health and performance.

View Article: PubMed Central - PubMed

Affiliation: Dept. of Kinesiology, University of Lethbridge, 4401 University Drive, Lethbridge AB, Canada.

ABSTRACT
Ultra-endurance competitions are becoming increasingly popular but there is limited research on female participants. The purpose of this study was to examine changes in estrogen and the IGF-I system in women after an ultra-marathon. Six pairs of pre- and post- menopausal women were matched for race finish times;mean finish time was 20 hours. Blood samples were drawn 24 hours before the race, at the finish, and 24 hours into recovery. Samples were analysed for estradiol, total IGF-I, IGFBP-1, and intact IGFBP-3. There was a significant increase in estradiol following the race in both groups (P < 0.05). Total IGF-I decreased after the race (P < 0.01) and remained lower in recovery. IGFBP-1 increased after the race (P < 0.001) but returned to pre-race levels after 24 hours, while intact IGFBP-3 was significantly lower post-race and in recovery (P < 0.001). Postmenopausal women had significantly lower estradiol at baseline, but there were no other group differences. These results demonstrate that among recreational female runners, an ultra-marathon is associated with IGF system changes that are consistent with an energy-deficient, catabolic state. Further research is needed to confirm the effect of these endocrine changes on health and performance.

No MeSH data available.


Related in: MedlinePlus