scholarly journals The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis

2020 ◽  
Vol 50 (10) ◽  
pp. 1813-1827 ◽  
Author(s):  
Kelly Lee McNulty ◽  
Kirsty Jayne Elliott-Sale ◽  
Eimear Dolan ◽  
Paul Alan Swinton ◽  
Paul Ansdell ◽  
...  
Keyword(s):  
Systematic Review ◽  
Menstrual Cycle ◽  
Effect Size ◽  
Exercise Performance ◽  
Meta Analysis ◽  
Experimental Studies ◽  
Follicular Phase ◽  
Effect Sizes ◽  
Cycle Phase ◽  
Early Follicular Phase

Abstract Background Concentrations of endogenous sex hormones fluctuate across the menstrual cycle (MC), which could have implications for exercise performance in women. At present, data are conflicting, with no consensus on whether exercise performance is affected by MC phase. Objective To determine the effects of the MC on exercise performance and provide evidence-based, practical, performance recommendations to eumenorrheic women. Methods This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Four databases were searched for published experimental studies that investigated the effects of the MC on exercise performance, which included at least one outcome measure taken in two or more defined MC phases. All data were meta-analysed using multilevel models grounded in Bayesian principles. The initial meta-analysis pooled pairwise effect sizes comparing exercise performance during the early follicular phase with all other phases (late follicular, ovulation, early luteal, mid-luteal and late luteal) amalgamated. A more comprehensive analysis was then conducted, comparing exercise performance between all phases with direct and indirect pairwise effect sizes through a network meta-analysis. Results from the network meta-analysis were summarised by calculating the Surface Under the Cumulative Ranking curve (SUCRA). Study quality was assessed using a modified Downs and Black checklist and a strategy based on the recommendations of the Grading of Recommendations Assessment Development and Evaluation (GRADE) working group. Results Of the 78 included studies, data from 51 studies were eligible for inclusion in the initial pairwise meta-analysis. The three-level hierarchical model indicated a trivial effect for both endurance- and strength-based outcomes, with reduced exercise performance observed in the early follicular phase of the MC, based on the median pooled effect size (ES0.5 = − 0.06 [95% credible interval (CrI): − 0.16 to 0.04]). Seventy-three studies had enough data to be included in the network meta-analysis. The largest effect was identified between the early follicular and the late follicular phases of the MC (ES0.5 = − 0.14 [95% CrI: − 0.26 to − 0.03]). The lowest SUCRA value, which represents the likelihood that exercise performance is poor, or among the poorest, relative to other MC phases, was obtained for the early follicular phase (30%), with values for all other phases ranging between 53 and 55%. The quality of evidence for this review was classified as “low” (42%). Conclusion The results from this systematic review and meta-analysis indicate that exercise performance might be trivially reduced during the early follicular phase of the MC, compared to all other phases. Due to the trivial effect size, the large between-study variation and the number of poor-quality studies included in this review, general guidelines on exercise performance across the MC cannot be formed; rather, it is recommended that a personalised approach should be taken based on each individual's response to exercise performance across the MC.

scholarly journals The Effects of Oral Contraceptives on Exercise Performance in Women: A Systematic Review and Meta-analysis

2020 ◽  
Vol 50 (10) ◽  
pp. 1785-1812 ◽  
Author(s):  
Kirsty J. Elliott-Sale ◽  
Kelly L. McNulty ◽  
Paul Ansdell ◽  
Stuart Goodall ◽  
Kirsty M. Hicks ◽  
...  
Keyword(s):  
Menstrual Cycle ◽  
Exercise Performance ◽  
Meta Analysis ◽  
Group Analysis ◽  
Comparison Method ◽  
Follicular Phase ◽  
Current Evidence ◽  
Early Follicular Phase ◽  
Menstruating Women ◽  
Meta Analyses

Abstract Background Oral contraceptive pills (OCPs) are double agents, which downregulate endogenous concentrations of oestradiol and progesterone whilst simultaneously providing daily supplementation of exogenous oestrogen and progestin during the OCP-taking days. This altered hormonal milieu differs significantly from that of eumenorrheic women and might impact exercise performance, due to changes in ovarian hormone-mediated physiological processes. Objective To explore the effects of OCPs on exercise performance in women and to provide evidence-based performance recommendations to users. Methods This review complied with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A between-group analysis was performed, wherein performance of OCP users was compared with naturally menstruating women, and a within-group analysis was conducted, wherein performance during OCP consumption was compared with OCP withdrawal. For the between-group analysis, women were phase matched in two ways: (1) OCP withdrawal versus the early follicular phase of the menstrual cycle and (2) OCP consumption versus all phases of the menstrual cycle except for the early follicular phase. Study quality was assessed using a modified Downs and Black Checklist and a strategy based on the recommendations of the Grading of Recommendations Assessment Development and Evaluation working group. All meta-analyses were conducted within a Bayesian framework to facilitate probabilistic interpretations. Results 42 studies and 590 participants were included. Most studies (83%) were graded as moderate, low or very low quality, with 17% achieving high quality. For the between-group meta-analysis comparing OCP users with naturally menstruating women, posterior estimates of the pooled effect were used to calculate the probability of at least a small effect (d ≥ 0.2). Across the two between-group comparison methods, the probability of a small effect on performance favouring habitual OCP users was effectually zero (p < 0.001). In contrast, the probability of a small effect on performance favouring naturally menstruating women was moderate under comparison method (1) (d ≥ 0.2; p = 0.40) and small under comparison method (2) (d ≥ 0.2; p = 0.19). Relatively large between-study variance was identified for both between-group comparisons ($$\tau$$ τ 0.5 = 0.16 [95% credible interval (CrI) 0.01–0.44] and $$\tau$$ τ 0.5 = 0.22 [95% CrI 0.06–0.45]). For the within-group analysis comparing OCP consumption with withdrawal, posterior estimates of the pooled effect size identified almost zero probability of a small effect on performance in either direction (d ≥ 0.2; p ≤ 0.001). Conclusions OCP use might result in slightly inferior exercise performance on average when compared to naturally menstruating women, although any group-level effect is most likely to be trivial. Practically, as effects tended to be trivial and variable across studies, the current evidence does not warrant general guidance on OCP use compared with non-use. Therefore, when exercise performance is a priority, an individualised approach might be more appropriate. The analysis also indicated that exercise performance was consistent across the OCP cycle.

Systematic Reviews and Meta-Analyses of Crime Prevention Evaluations

2018 ◽  
Author(s):  
Anthony Petrosino ◽  
Claire Morgan ◽  
Trevor Fronius
Keyword(s):  
Systematic Review ◽  
Systematic Reviews ◽  
Effect Size ◽  
Meta Analysis ◽  
Experimental Studies ◽  
Small Sample ◽  
Effect Sizes ◽  
What Works ◽  
Management Procedures ◽  
Meta Analyses

Systematic reviews and meta-analyses have become a focal point of evidence-based policy in criminology. Systematic reviews use explicit and transparent processes to identify, retrieve, code, analyze, and report on existing research studies bearing on a question of policy or practice. Meta-analysis can combine the results from the most rigorous evaluations identified in a systematic review to provide policymakers with the best evidence on what works for a variety of interventions relevant to reducing crime and making the justice system fairer and more effective. The steps of a systematic review using meta-analysis include specifying the topic area, developing management procedures, specifying the search strategy, developing eligibility criteria, extracting data from the studies, computing effect sizes, developing an analysis strategy, and interpreting and reporting the results. In a systematic review using meta-analysis, after identifying and coding eligible studies, the researchers create a measure of effect size for each experimental versus control contrast of interest in the study. Most commonly, reviewers do this by standardizing the difference between scores of the experimental and control groups, placing outcomes that are conceptually similar but measured differently (e.g., such as re-arrest or reconviction) on the same common scale or metric. Though these are different indices, they do measure a program’s effect on some construct (e.g., criminality). These effect sizes are usually averaged across all similar studies to provide a summary of program impact. The effect sizes also represent the dependent variable in the meta-analysis, and more advanced syntheses explore the role of potential moderating variables, such as sample size or other characteristics related to effect size. When done well and with full integrity, a systematic review using meta-analysis can provide the most comprehensive assessment of the available evaluative literature addressing the research question, as well as the most reliable statement about what works. Drawing from a larger body of research increases statistical power by reducing standard error; individual studies often use small sample sizes, which can result in large margins of error. In addition, conducting meta-analysis can be faster and less resource-intensive than replicating experimental studies. Using meta-analysis instead of relying on an individual program evaluation can help ensure that policy is guided by the totality of evidence, drawing upon a solid basis for generalizing outcomes.

scholarly journals Sex Differences and Menstrual Cycle Phase-Dependent Modulation of Craving for Cigarette: An fMRI Pilot Study

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Adrianna Mendrek ◽  
Laurence Dinh-Williams ◽  
Josiane Bourque ◽  
Stéphane Potvin
Keyword(s):  
Sex Differences ◽  
Menstrual Cycle ◽  
Parietal Lobe ◽  
Follicular Phase ◽  
Cycle Phase ◽  
Functional Neuroanatomy ◽  
Early Follicular Phase ◽  
Hormonal Fluctuations ◽  
Women And Girls ◽  
The Right

While overall more men than women smoke cigarettes, women and girls take less time to become dependent after initial use and have more difficulties quitting the habit. One of the factors contributing to these differences may be that women crave cigarettes more than men and that their desire to smoke is influenced by hormonal fluctuations across the menstrual cycle. Therefore, the purpose of the present study was twofold: (a) to examine potential sex/gender differences in functional neuroanatomy of craving and to (b) delineate neural correlates of cigarette cravings in women across their menstrual cycle. Fifteen tobacco-smoking men and 19 women underwent a functional MRI during presentation of neutral and smoking-related images, known to elicit craving. Women were tested twice: once during early follicular phase and once during midluteal phase of their menstrual cycle. The analysis did not reveal any significant sex differences in the cerebral activations associated with craving. Nevertheless, the pattern of activations in women varied across their menstrual cycle with significant activations in parts of the frontal, temporal, and parietal lobe, during follicular phase, and only limited activations in the right hippocampus during the luteal phase.

scholarly journals Effect of menstrual cycle phase, menstrual irregularities and hormonal contraceptive use on anterior knee laxity and non-contact anterior cruciate ligament injury occurrence in women: a protocol for a systematic review and meta-analysis

2021 ◽  
Vol 7 (4) ◽  
pp. e001170
Author(s):  
Elisa Nédélec ◽  
Elvis Foli ◽  
Sandra J Shultz ◽  
Paul A Swinton ◽  
Eimear Dolan ◽  
...  
Keyword(s):  
Systematic Review ◽  
Menstrual Cycle ◽  
Cruciate Ligament ◽  
Meta Analysis ◽  
Ligament Injury ◽  
Secondary Outcome ◽  
Hormonal Contraceptives ◽  
Cycle Phase ◽  
Acl Injuries ◽  
Anterior Knee

Exercising women report three to six times more ACL tears than men, which happen, in the majority of cases, with a non-contact mechanism. This sex disparity has, in part, been attributed to the differences in reproductive hormone profiles between men and women. Many studies have shown that anterior knee (AK) laxity and the rate of non-contact ACL injuries vary across the menstrual cycle, but these data are inconsistent. Similarly, several studies have investigated the potential protective effect of hormonal contraceptives on non-contact ACL injuries, but their conclusions are also variable. The purpose of this systematic review and meta-analysis is to, identify, evaluate and summarise the effects of endogenous and exogenous ovarian hormones on AK laxity (primary outcome) and the occurrence of non-contact ACL injuries (secondary outcome) in women. We will perform a systematic search for all observational studies conducted on this topic. Studies will be retrieved by searching electronic databases, clinical trial registers, author’s personal files and cross-referencing selected studies. Risk of bias will be assessed using the Newcastle Ottawa Quality Assessment Scale for Cohort and Case–Control Studies. Certainty in the cumulative evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. The meta-analyses will use a Bayesian approach to address specific research questions in a more intuitive and probabilistic manner. This review is registered on the international database of prospectively registered systematic reviews (PROSPERO; CRD42021252365).

scholarly journals Exacerbation of Psychosis During the Perimenstrual Phase of the Menstrual Cycle: Systematic Review and Meta-analysis

2019 ◽  
Vol 46 (1) ◽  
pp. 78-90 ◽  
Author(s):  
Thomas J Reilly ◽  
Vanessa C Sagnay de la Bastida ◽  
Dan W Joyce ◽  
Alexis E Cullen ◽  
Philip McGuire
Keyword(s):  
Systematic Review ◽  
Menstrual Cycle ◽  
Random Effects ◽  
Psychotic Disorders ◽  
Meta Analysis ◽  
Psychotic Symptoms ◽  
Cycle Phase ◽  
Menstrual Cycle Phase ◽  
Psychiatric Admission ◽  
Admission Rates

Abstract Psychotic disorders can be exacerbated by the hormonal changes associated with childbirth, but the extent to which exacerbations occur with the menstrual cycle is unclear. We addressed this issue by conducting a systematic review. Embase, Medline, and PsychINFO databases were searched for studies that measured exacerbations of psychotic disorders in relation to the menstrual cycle. We extracted exacerbation measure, definition of menstrual cycle phase, and measurement of menstrual cycle phase. Standard incidence ratios were calculated for the perimenstrual phase based on the observed admissions during this phase divided by the expected number of admissions if the menstrual cycle had no effect. Random effects models were used to examine pooled rates of psychiatric admission in the perimenstrual phase. Nineteen studies, comprising 1193 participants were eligible for inclusion. Eleven studies examined psychiatric admission rates, 5 examined symptoms scores, 2 examined self-reported exacerbation, and 1 examined both admission rates and symptom scores. A random effects model demonstrated the rate of admissions during the perimenstrual phase was 1.48 times higher than expected (95% CI: 1.31–1.67), with no significant heterogeneity detected. Four of six symptom score studies reported perimenstrual worsening, but lack of consistency in timepoints precluded meta-analysis. Two studies examining self-reported menstrual exacerbations reported prevalences ranging from 20% to 32.4%. Psychiatric admission rates are significantly higher than expected during the perimenstrual phase. There is some evidence that a worsening of psychotic symptoms also occurs during this phase, but further research with more precise measurement of the menstrual cycle and symptomatology is required.

Impact of the menstrual cycle on peripheral vascular function in premenopausal women: systematic review and meta-analysis

2020 ◽  
Vol 319 (6) ◽  
pp. H1327-H1337
Author(s):  
Jennifer S. Williams ◽  
Emily C. Dunford ◽  
Maureen J. MacDonald
Keyword(s):  
Systematic Review ◽  
Menstrual Cycle ◽  
Endothelial Function ◽  
Vascular Function ◽  
Meta Analysis ◽  
Premenopausal Women ◽  
Cycle Phase ◽  
Peripheral Vascular ◽  
The Impact

Fluctuations in endogenous hormones estrogen and progesterone during the menstrual cycle may offer vasoprotection for endothelial and smooth muscle (VSM) function. While numerous studies have been published, the results are conflicting, leaving our understanding of the impact of the menstrual cycle on vascular function unclear. The purpose of this systematic review and meta-analysis was to consolidate available research exploring the role of the menstrual cycle on peripheral vascular function. A systematic search of MEDLINE, Web of Science, and EMBASE was performed for articles evaluating peripheral endothelial and VSM function across the natural menstrual cycle: early follicular (EF) phase versus late follicular (LF), early luteal, mid luteal, or late luteal. A meta-analysis examined the effect of the menstrual cycle on the standardized mean difference (SMD) of the outcome measures. Analysis from 30 studies ( n = 1,363 women) observed a “very low” certainty of evidence that endothelial function increased in the LF phase (SMD: 0.45, P = 0.0001), with differences observed in the macrovasculature but not in the microvasculature (SMD: 0.57, P = 0.0003, I2 = 84%; SMD: 0.21, P = 0.17, I2 = 34%, respectively). However, these results are partially explained by differences in flow-mediated dilation [e.g., discrete (SMD: 0.86, P = 0.001) vs. continuous peak diameter assessment (SMD: 0.25, P = 0.30)] and/or menstrual cycle phase methodologies. There was a “very low” certainty that endothelial function was largely unchanged in the luteal phases, and VSM was unchanged across the cycle. The menstrual cycle appears to have a small effect on macrovascular endothelial function but not on microvascular or VSM function; however, these results can be partially attributed to methodological differences.

scholarly journals T141. EFFECTS OF MENSTRUAL CYCLE ON RESTING STATE FUNCTIONAL CONNECTIVITY IN SCHIZOPHRENIA: A FUNCTIONAL MRI STUDY

2020 ◽  
Vol 46 (Supplement_1) ◽  
pp. S284-S285
Author(s):  
Handan Noyan ◽  
Andaç Hamamcı ◽  
Zeynep Fırat ◽  
Ayşegül Sarsılmaz Oygen ◽  
Alp Üçok
Keyword(s):  
Menstrual Cycle ◽  
Functional Connectivity ◽  
Resting State ◽  
Ovarian Hormones ◽  
Follicular Phase ◽  
Cycle Phase ◽  
Resting State Functional Connectivity ◽  
Brain Functions ◽  
Early Follicular Phase ◽  
The Mean

Abstract Background The menstrual cycle is a favorable model for examining the influence of ovarian hormones on cognition, emotion and brain functions. Ovarian hormones have substantial effects on task-related brain activity, but their impacts on functional connectivity at rest have been investigated by a few studies conducted with healthy individuals and these pre-existing findings are inconsistent. As for schizophrenia, different influences of ovarian hormones were reported. For instance, the estrogen hypothesis of schizophrenia has suggested that estrogen plays a neuroprotective role in the pathophysiology of this disorder. The present study investigates resting state functional connectivity (RS-FC) alterations related to menstrual cycle phase and/or hormone levels in patients with schizophrenia and healthy controls and aims to contribute to the understanding of the effects of ovarian hormones on the pathogenesis of schizophrenia and brain functions. Methods The study was conducted with 13 women with schizophrenia (the mean of age: 32 ± 7.67) and 13 healthy women (the mean of age: 30.08 ± 7.27). Resting state functional Magnetic Resonance Imaging (fMRI) scanning, as well as hormonal and clinical assessments, were applied to each participant twice, during two menstrual cycle phases: early follicular (Days 2–6; low estrogen/progesterone) and mid-luteal (Days 20–22; high estrogen/progesterone). The serum hormone levels of estradiol, progesterone, prolactin (only in the patients), follicle-stimulating and luteinizing were assessed. The clinical assessment interviews included the Brief Psychiatric Rating Scales, the Clinical Global Impression (only for the patients), the Global Assessment of Functioning and the Calgary Depression Rating Scale for Schizophrenia (for both groups). Results Our findings revealed that no cycle phase-related alterations existed in RS-FC in both groups. However, specific correlations between each hormone and RS-FC were found in both cycle phases for two groups. In the patients, estrogen was positively correlated with the auditory network (AN) connectivity in the left amygdala at the early follicular phase. In the controls, the positive correlations to progesterone were found in the precuneus for the connectivity of the posterior default mode network (DMN) and the left-frontoparietal network (FPN) during the early follicular phase. Also, progesterone was negatively correlated with the executive control network (ECN) connectivity in the right superior frontal gyrus at the mid-luteal phase in the controls. Furthermore, the patients had lower progesterone levels during the mid-luteal phase compared to the controls (p&lt;0.05). The severity of the psychotic symptoms of the patients didn’t change between the cycle phases. Discussion To our knowledge, this is the first study to examine the influence of the menstrual cycle on the brain’s RS-FC in schizophrenia. Our results indicated that the effects of the menstrual cycle on RS-FC were more prominent in the controls rather than the patients with schizophrenia; and that the findings for the patient group may be associated with the additional mechanisms responsible from schizophrenia. This might imply that differentiating the menstrual cycle effects is difficult in a complex disorder such as schizophrenia. The results obtained from the controls are consistent with the previous findings indicating that the menstrual cycle effects might be associated with the connectivity of the DMN and cognition-related networks. Moreover, our results suggested that estrogen might have a modulating effect on the intrinsic functional connectivity changes in the patients, while progesterone, might mediate to that in the controls.

Effect of High-Fat or High-Carbohydrate Diets on Endurance Exercise: A Meta-Analysis

2005 ◽  
Vol 15 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Matthew Erlenbusch ◽  
Mark Haub ◽  
Kathy Munoz ◽  
Susan MacConnie ◽  
Belinda Stillwell
Keyword(s):  
Endurance Exercise ◽  
Effect Size ◽  
Exercise Performance ◽  
Meta Analysis ◽  
High Carbohydrate Diet ◽  
Effect Sizes ◽  
Significant Heterogeneity ◽  
High Fat ◽  
Carbohydrate Diet ◽  
High Carbohydrate

The purpose of this investigation was to clarify, via a meta-analysis, whether the literature favors a high-fat or a high-carbohydrate diet to yield superior endurance exercise performance. Twenty published trials were analyzed to compare exercise performance under different diets. The average effect size of −0.60 indicated that subjects following a high-carbohydrate diet exercised longer until exhaustion. The training status of subjects (trained vs. untrained) was significantly related to effect size (r = −0.576, P < 0.01) and effect sizes separated between trained and untrained subjects were −0.05 and −2.84 respectively. The test for homogeneity revealed significant heterogeneity among effect sizes (χ2 [19] = 43.30, P < 0.05), indicating all of the trials are not describing the same effect. Given this significant heterogeneity, a conclusive endorsement of a high-carbohydrate diet based on the literature is difficult to make. Highly dissimilar trial protocols are the primary reason for heterogeneity.

Sign in / Sign up

Export Citation Format

Share Document