Bidirectional Interactions between the Menstrual Cycle, Exercise Training, and Macronutrient Intake in Women: A Review

Effects of exercise on sex steroid hormones (estrogen, progesterone, testosterone) in eumenorrheic females: A systematic to review and meta-analysis

BACKGROUND

The sex steroid hormones fluctuate during the menstrual cycle, which affects the strength and postural stability of females and leads to injuries and risk of falls. These hormones may be modulated by exercise to impact the overall health of females.

OBJECTIVE

To determine the effects of exercise on sex steroid hormones in eumenorrheic females.

METHODS

This review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA) guidelines in Lahore, Pakistan. The full-length articles were searched using these databases/search engines (PubMed, Web of Science and Google Scholar, Sci-Hub). Randomized controlled trials along with single group experimental studies were also included. All types of exercises were compared with no exercise in the control group. The Cochrane Risk of Bias assessment tool assessed and screened the articles. The data were then analyzed. The primary outcomes were the levels of estrogen, progesterone and testosterone.

RESULTS

Eleven studies were included (5 randomized controlled trials and 6 quasi-experimental studies). The effects of exercise on free estradiol concentration and serum progesterone level were not significant [p = 0.37 (SMD = 0.33, 95% CI = 0.14 to 0.74, I2 = 0%) and p = 0.84 (S.D= -0.65, C.I= -6.92 to 5.62, I2 = 94%)] respectively, whereas, the effects on testosterone levels were significant [p value < 0.00001 (M.D = 0.89, 95% C.I= -2.16 to 3.95, I2 = 94%)].

CONCLUSION

A blinded randomized controlled trial should be conducted in which a structured approach should be followed by women along with warm-ups, cool down and rest intervals.

TRIAL REGISTRATION NUMBER

The systematic review was registered prospectively on PROSPERO with registration number CRD42023473767.

Modulatory effects of estrous cycle on ingestive behaviors and energy balance in young adult C57BL/6J mice maintained on a phytoestrogen-free diet

The estrous cycle is known to modify food, fluid, and electrolyte intake behaviors and energy homeostasis in various species, in part through fluctuations in estrogen levels. Simultaneously, commonly commercially available rodent dietary formulations greatly vary in soy protein content, and thereby the delivery of biologically active phytoestrogens. To explore the interactions among the estrous cycle, sodium, fluid, and caloric seeking behaviors, and energy homeostasis, young adult C57BL/6J female mice were maintained on a soy protein-free 2920x diet and provided water, or a choice between water and 0.15 mol/L NaCl drink solution. Comprehensive metabolic phenotyping was performed using a multiplexed Promethion (Sable Systems International) system, and estrous stages were determined via daily vaginal cytology. When provided food and water, estrous cycling had no major modulatory effects on intake behaviors or energy balance. When provided a saline solution drink choice, significant modulatory effects of the transition from diestrus to proestrus were observed upon fluid intake patterning, locomotion, and total energy expenditure. Access to saline increased total daily sodium consumption and aspects of energy expenditure, but these effects were not modified by the estrous stage. Collectively, these results indicate that when supplied a phytoestrogen-free diet, the estrous cycle has minor modulatory effects on ingestive behaviors and energy balance in C57BL/6J mice that are sensitive to sodium supply.NEW & NOTEWORTHY When provided a phytoestrogen-free diet, the estrous cycle had very little effect on food and water intake, physical activity, or energy expenditure in C57BL/6J mice. In contrast, when provided an NaCl drink in addition to food and water, the estrous cycle was associated with changes in intake behaviors and energy expenditure. These findings highlight the complex interactions among estrous cycling, dietary formulation, and nutrient presentation upon ingestive behaviors and energy homeostasis in mice.

Plyometric-Jump Training Effects on Physical Fitness and Sport-Specific Performance According to Maturity: A Systematic Review with Meta-analysis

BACKGROUND

Among youth, plyometric-jump training (PJT) may provide a safe, accessible, and time-efficient training method. Less is known on PJT effectiveness according to the maturity status.

OBJECTIVE

This systematic review with meta-analysis set out to analyse the body of peer-reviewed articles assessing the effects of PJT on measures of physical fitness [i.e., maximal dynamic strength; change of direction (COD) speed; linear sprint speed; horizontal and vertical jump performance; reactive strength index] and sport-specific performance (i.e., soccer ball kicking and dribbling velocity) according to the participants' maturity status.

METHODS

Systematic searches were conducted in three electronic databases using the following inclusion criteria: (i) Population: healthy participants aged < 18 years; (ii) Intervention: PJT program including unilateral and/or bilateral jumps; (iii) Comparator: groups of different maturity status with control groups; (iv) Outcomes: at least one measure of physical fitness and/or sport-specific performance before and after PJT; (v) experimental design with an active or passive control group, and two or more maturity groups exposed to the same PJT. The DerSimonian and Laird random-effects models were used to compute the meta-analysis. The methodological quality of the studies was assessed using the PEDro checklist. GRADE was applied to assess certainty of evidence.

RESULTS

From 11,028 initially identified studies across three electronic databases, 11 studies were finally eligible to be meta-analysed (n total = 744; seven studies recruited males; four studies recruited females). Three studies were rated as high quality (6 points), and eight studies were of moderate quality (5 points). Seven studies reported the maturity status using age at peak height velocity (PHV; pre-PHV values up to - 2.3; post-PHV up to 2.5). Another four studies used Tanner staging (from Tanner I to V). The training programmes ranged from 4 to 36 weeks, using 1-3 weekly training sessions. When compared to controls, pre-PHV and post-PHV participants obtained small-to-moderate improvements (ES = 0.35 - 0.80, all p < 0.05) in most outcomes (i.e., sport-specific performance; maximal dynamic strength; linear sprint; horizontal jump; reactive strength index) after PJT. The contrast of pre-PHV with post-PHV youth revealed that PJT was similarly effective in both maturity groups, in most outcome measures except for COD speed (in favour of pre-PHV). PJT induces similar physical fitness and sport-specific performance benefits in males and females, with a minimal exercise dosage of 4 weeks (8 intervention sessions), and 92 weekly jumps. Results of this meta-analysis are based on low study heterogeneity, and low to very low certainty of evidence (GRADE analysis) for all outcomes.

CONCLUSION

Compared to control participants, PJT resulted in improved maximal dynamic strength, linear sprint speed, horizontal jump performance, reactive strength index, and sport-specific performance (i.e., soccer ball kicking and dribbling velocity). These effects seem to occur independently of the maturity status, as both pre-PHV and post-PHV participants achieved similar improvements after PJT interventions for most outcomes. However, several methodological issues (e.g., low sample sizes and the pooling of maturity categories) preclude the attainment of more robust recommendations at the current time. To address this issue, consistency in maturity status reporting strategies must be improved in future studies with the general youth population and youth athletes.

The experiences of menstrual symptom changes among international students studying in China during the acculturation period: A phenomenology study

Objectives

Menstruation is a normal physiological phenomenon among female which could be influenced by the process of acculturation. Few studies have explored the experience of menstrual symptom changes among international female students studying in China. Therefore, this paper aims to summarize international female students' experiences of menstrual symptom changes when they were studying in China and interpret these changes through considering the influence of acculturation on their social and academic lives.

Methods

We used a descriptive phenomenology approach. Structured in-depth face-to-face interviews were conducted between May and November 2019 among ten international female students studying in one Province located in south central China. Participants were those who reported having experienced menstrual symptom changes during the acculturation period, which was defined as the first six months of living in China. All interviews were audio-recorded, transcribed verbatim, and analyzed using NVivo 11.0 with the guidance of Colaizzi's seven-step method.

Results

The international female students' experiences of menstrual symptom changes were summarized and grouped into five main categories and 13 subcategories. The main categories include: 1) demonstration of menstrual symptom changes, 2) challenges of maintaining menstrual function in the new setting, 3) coping styles to take care of menstrual health, 4) consequences of the menstrual symptom changes, and 5) culture-based attitude toward menstruation.

Conclusions

International female students reported experiences of menstrual symptom changes, including somatic and psychological symptoms during the acculturation period. Culture barriers, academic stress, and sleep patterns are common factors influencing their menstrual symptom changes. More culturally-tailored interventions should be explored to improve the menstrual health of international female students in China.

Interaction predictors of self-perception menstrual symptoms and influence of the menstrual cycle on physical performance of physically active women

OBJECTIVE

To analyze the physical performance, self-perception menstrual symptoms, of physically active eumenorrheic women with endogenous ovarian cycle in two phases of the menstrual cycle.

METHODS

Twenty-six women participated in the study (age 25.8 ± 3.9 years; height 1.64 ± 0.58 m; mass 64 ± 12.32 kg; menarche 11.69 ± 1.28 years). Assessments were performed in two phases of the menstrual cycle (MC), Early-Follicular Phase (FP) and Mid-Luteal Phase (LP), performance was assessed through total time to exhaustion (TTE), complete stages (CE), and final speed (FE), through a graded exercise test (GXT). Information on the participants' menstrual symptoms and their perceptions of the influence of MC on their performance were also collected. Data normality was assessed using the Shapiro-Wilk test. Paired analyses were conducted (t test or Wilcoxon) to examine the responses between the menstrual phases. The interaction analysis of symptom predictors was performed by multiple linear regression, with a significance level of p ≤ 0.05.

RESULTS

There was no significant difference in physical performance between the phases during the GXT in TTE (mean difference 8.50; 95% CI - 11.99 to 42; p = 0.36). During FP, women with heavy flow had shorter performance in the GXT (t = - 2.5; p = 0.01), demonstrating an r² = 0.32. In LP, for the women who reported not having the perception of the influence of the menstrual cycle on exercise, the total test time was longer (t = 2.55; p = 0.01), with an r² = 0.45.

CONCLUSION

There was no difference in physical performance between FP and LP. However, menstrual flow intensity and perception of cycle interference demonstrated a decrease in TTE.

Nutrition and Physical Exercise in Women

While the benefits of nutrition and physical exercise are commonly studied separately, their concomitant integration has the potential to produce greater benefits in women than strategies focusing only on one or the other [...]

Nutritional Intake and Training Load of Professional Female Football Players during a Mid-Season Microcycle

Football (soccer) is a high-intensity intermittent sport with large energy demands. In a repeated-measures design, we analysed the nutritional intake and training load of fourteen female football players (22.50 ± 4.38 y; 57.23 ± 8.61 kg; 164 ± 6.00 cm; 18.33 ± 2.48% of fat mass and 23.71 ± 2.51 kg of muscle mass) competing in the highest female Football Portuguese League across a typical mid-season microcycle. The microcycle had one match day (MD), one recovery session (two days after the MD, MD+2), three training sessions (MD-3, MD-2, MD-1) and two rest days (MD+1). Energy intake and CHO (g.kg.BW−1) intake were lower on the days before the competition (MD+2, MD-3, MD-2 and MD-1 vs. MD; p < 0.05; ES: 0.60−1.30). Total distance, distance covered at high-speed running (HSRD) and the high metabolic distance load (HMLD) were lower on MD+2, MD-3 and MD-1 compared with MD (p < 0.05; ES: <0.2−5.70). The internal training load was lower in all training sessions before the competition (MD+2, MD-3, MD-2 and MD-1 vs. MD; p ≤ 0.01; ES: 1.28−5.47). Despite the small sample size and a single assessment in time, the results suggest that caloric and CHO intake were below the recommendations and were not structured based on the physical requirements for training sessions or match days.

Effects of Exercise Training on the Autonomic Nervous System with a Focus on Anti-Inflammatory and Antioxidants Effects

Studies show that the autonomic nervous system (ANS) has an important impact on health in general. In response to environmental demands, homeostatic processes are often compromised, therefore determining an increase in the sympathetic nervous system (SNS)’s functions and a decrease in the parasympathetic nervous system (PNS)’s functions. In modern societies, chronic stress associated with an unhealthy lifestyle contributes to ANS dysfunction. In this review, we provide a brief introduction to the ANS network, its connections to the HPA axis and its stress responses and give an overview of the critical implications of ANS in health and disease—focused specifically on the immune system, cardiovascular, oxidative stress and metabolic dysregulation. The hypothalamic–pituitary–adrenal axis (HPA), the SNS and more recently the PNS have been identified as regulating the immune system. The HPA axis and PNS have anti-inflammatory effects and the SNS has been shown to have both pro- and anti-inflammatory effects. The positive impact of physical exercise (PE) is well known and has been studied by many researchers, but its negative impact has been less studied. Depending on the type, duration and individual characteristics of the person doing the exercise (age, gender, disease status, etc.), PE can be considered a physiological stressor. The negative impact of PE seems to be connected with the oxidative stress induced by effort.