Search Results

You are looking at 1 - 10 of 36 items for :

  • "progesterone" x
Clear All
Restricted access

Karen J. Reading, Linda J. McCargar and Vicki J. Harber

Menstrual abnormalities are associated with negative energy balance and reduced energy expenditure (REE). To examine this relationship in elite adolescent aesthetic athletes, 3 groups of females (aged 15-18 years) were studied: 10 oligo/amenorrheic athletes (OA), 11 eumenorrheic athletes (EA), and 8 non-athlete controls (C). Components of energy balance, body composition, dietary restraint, pubertal maturation, and luteal phase salivary progesterone were assessed in all groups. Both groups of athletes had a later age of menarche and lowerpubertal development score compared to the non-athletes (p < .05). With the exception of salivary progesterone (ng/ml; OA = 0.15±0.01 <EA = 0.29± 0.1 and C = 0.30 ± 0.13, /p = .007), there were no differences between the athlete groups. Energy balance (kcal/d) in the OA group was lower (−290 ± 677) compared to either EA (−5±461) or C (179 ± 592) but did not reach significance (p = .24). Dietary energy intake and absolute REE (kcal/d) were not different among groups, despite detectable differences in reproductive status, and thus could not be attributed to differences in energy balance or REE.

Restricted access

Beatriz Rael, Nuria Romero-Parra, Víctor M. Alfaro-Magallanes, Laura Barba-Moreno, Rocío Cupeiro, Xanne Janse de Jonge, Ana B. Peinado and on Behalf of the IronFEMME Study Group

Female endogenous (17β-estradiol and progesterone) and exogenous (ethinyl estradiol and progestin) hormones play a key role in the reproductive system. Furthermore, there are several nonreproductive tissues, such as the hypothalamus, cardiovascular system, kidney tubules, liver, skeletal muscle

Restricted access

Marc Sim, Brian Dawson, Grant Landers, Debbie Trinder and Peter Peeling

The trace element iron plays a number of crucial physiological roles within the body. Despite its importance, iron deficiency remains a common problem among athletes. As an individual’s iron stores become depleted, it can affect their well-being and athletic capacity. Recently, altered iron metabolism in athletes has been attributed to postexercise increases in the iron regulatory hormone hepcidin, which has been reported to be upregulated by exercise-induced increases in the inflammatory cytokine interleukin-6. As such, when hepcidin levels are elevated, iron absorption and recycling may be compromised. To date, however, most studies have explored the acute postexercise hepcidin response, with limited research seeking to minimize/attenuate these increases. This review summarizes the current knowledge regarding the postexercise hepcidin response under a variety of exercise scenarios and highlights potential areas for future research—such as: a) the use of hormones though the female oral contraceptive pill to manipulate the postexercise hepcidin response, b) comparing the use of different exercise modes (e.g., cycling vs. running) on hepcidin regulation.

Restricted access

Paola Rodriguez-Giustiniani and Stuart D.R. Galloway

attempts to address the influence of different levels of endogenous, circulating steroid hormones on this topic in women. Key hormones, such as progesterone and estrogens, could exert a profound control over the regulation of fluid and electrolyte balance ( Spruce et al., 1985 ; Stachenfeld, 2008 , 2009

Restricted access

Pamela S. Hinton, Laura S. Hillman and Rebecca D. Imhoff

We compared bone mineral density and turnover in women with exercise-associated menstrual disorders (AMD, n=10; 0–9 cycles·y−1), hormonal contraceptive users (AHC, n=16; 12 cycles·y−1), and regularly menstruating controls (AE, n=13; 10–13 cycles·y−1). Thirty-nine active women (≥ 5 h aerobic exercise/wk) participated in this cross-sectional study. BMD was lower in AMD vs. AHC and AE . Serum hormone and bone turnover markers did not differ between AMD and AE. Cortisol was elevated (P=0.0002), progesterone suppressed (P=0.05), and bone alkaline phosphatase significantly lower (P=0.03) in AHC vs. AE. Lifetime missed menstrual cycles and body weight were significant, independent predictors of lumbar spine BMD, regardless of current menstrual status (adj R2=42.8%). Exercise-associated menstrual disorders have a negative effect on BMD.

Restricted access

Claire Rechichi, Brian Dawson and Carmel Goodman

Some reports suggest variation in physiological responses and athletic performance, for female athletes at specific phases of the menstrual cycle. However, inconsistent findings are common due to the inappropriate verification of menstrual cycle phase, small subject numbers, high intra- and interindividual variability in estrogen and progesterone concentration, and the pulsatile secretion of these hormones. Therefore, the oral contraceptive (OC) cycle may provide a more stable environment in which to evaluate the acute effect of reproductive hormones on physiological variables and exercise performance. To date, most of the OC research has compared differences between OC use and nonuse, and few researchers have examined within-cycle effects of the OC. It is also apparent that OC use is becoming far more prevalent in athletes; hence the effect of the different exogenous and endogenous hormonal profiles on athletic performance should be investigated. Research to date identifies potential for variation in aerobic performance, anaerobic capacity, anaerobic power and reactive strength throughout an OC cycle. The purpose of this review is to present and evaluate the current literature on the physiology of exercise and athletic performance during the OC cycle.

Restricted access

Jason D. Vescovi and Jaci L. VanHeest

This observational case study examined the association of inter- and intraday energy intake and exercise energy expenditure with bone health, menstrual status and hematological factors in a female triathlete. The study spanned 7 months whereby energy intake and exercise energy expenditure were monitored three times (13 d); 16 blood samples were taken, urinary hormones were assessed for 3 months, and bone mineral density was measured twice. Energy availability tended to be sustained below 30 kcal/kg FFM/d and intraday energy intake patterns were often “back-loaded” with approximately 46% of energy consumed after 6 p.m. Most triiodothyronine values were low (1.1–1.2nmol/L) and supportive of reduced energy availability. The athlete had suppressed estradiol (105.1 ± 71.7pmol/L) and progesterone (1.79 ±1.19nmol/L) concentrations as well as urinary sex-steroid metabolites during the entire monitoring period. Lumbar spine (L1-L4) bone mineral density was low (age-matched Z-score −1.4 to −1.5). Despite these health related maladies the athlete was able to perform typical weekly training loads (swim: 30–40 km, bike: 120–300 km, run 45–70 km) and was competitive as indicated by her continued improvement in ITU World Ranking during and beyond the assessment period. There is a delicate balance between health and performance that can become blurred especially for endurance athletes. Education (athletes, coaches, parents) and continued monitoring of specific indicators will enable evidence-based recommendations to be provided and help reduced the risk of health related issues while maximizing performance gains. Future research needs to longitudinally examine how performance on standardized tests in each discipline (e.g., 800-m swim, 20-km time trial, 5-km run) is impacted when aspects of the female athlete triad are present.

Restricted access

Alon Eliakim

Introduction:

Competitive female athletes restrict energy intake and increase exercise energy expenditure frequently resulting in ovarian suppression. The purpose of this study was to determine the impact of ovarian suppression and energy deficit on swimming performance (400-m swim velocity).

Methods:

Menstrual status was determined by circulating estradiol (E2) and progesterone (P4) in ten junior elite female swimmers (15-17 yr). The athletes were categorized as cyclic (CYC) or ovarian-suppressed (OVS). They were evaluated every 2 weeks for metabolic hormones, bioenergetic parameters, and sport performance during the 12-week season.

Results:

CYC and OVS athletes were similar (p > .05) in age (CYC = 16.2 ± 1.8 yr, OVS = 17 ± 1.7 yr), body mass index (CYC = 21 ± 0.4 kg·m, OVS = 25 ± 0.8 kg·m), and gynecological age (CYC = 2.6 ± 1.1 yr, OVS = 2.8 ± 1.5 yr). OVS had suppressed P4 (p < .001) and E2 (p = .002) across the season. Total triiodothyronine (TT3) and insulin-like growth factor (IGF-1) were lower in OVS (TT3: CYC = 1.6 ± 0.2 nmol·L, OVS = 1.4 ± 0.1 nmol·L, p < .001; IGF-1: CYC = 243 ± 1 μg·mL, OVS = 214 μg·mL p < .001) than CYC at week 12. Energy intake (p < .001) and energy availability (p < .001) were significantly lower in OVS versus CYC. OVS exhibited a 9.8% decline in Δ400-m swim velocity compared with an 8.2% improvement in CYC at week 12.

Conclusions:

Ovarian steroids (P4 and E2), metabolic hormones (TT3 and IGF-1), and energy status markers (EA and EI) were highly correlated with sport performance. This study illustrates that when exercise training occurs in the presence of ovarian suppression with evidence for energy conservation (i.e., reduced TT3), it is associated with poor sport performance. These data from junior elite female athletes support the need for dietary periodization to help optimize energy intake for appropriate training adaptation and maximal sport performance

Restricted access

80 80 10.1123/ijsnem.12.1.73 Effect of Flavor and Awareness of Kilojoule Content of Drinks on Preference and Fluid Balance in Team Sports Michelle R. Minehan * Malcolm D. Riley * Louise M. Burke * 3 2002 12 12 1 1 81 81 92 92 10.1123/ijsnem.12.1.81 Energy Balance and Luteal Phase Progesterone

Restricted access

Nuria Romero-Parra, Victor Manuel Alfaro-Magallanes, Beatriz Rael, Rocío Cupeiro, Miguel A. Rojo-Tirado, Pedro J. Benito, Ana B. Peinado and on behalf of the IronFEMME Study Group

the 2 major phases of the menstrual cycle as follows: the follicular phase, focused on maturing a reproductive cell, and the luteal phase, focused on its regression. Thus, muscle damage response to exercise could vary accordingly. During the early follicular phase (EFP), both estrogen and progesterone