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15 result(s) for "Janse de Jonge, Xanne"
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Three-step method for menstrual and oral contraceptive cycle verification
Fluctuating endogenous and exogenous ovarian hormones may influence exercise parameters; yet control and verification of ovarian hormone status is rarely reported and limits current exercise science and sports medicine research. The purpose of this study was to determine the effectiveness of an individualised three-step method in identifying the mid-luteal or high hormone phase in endogenous and exogenous hormone cycles in recreationally-active women and determine hormone and demographic characteristics associated with unsuccessful classification. Cross-sectional study design. Fifty-four recreationally-active women who were either long-term oral contraceptive users (n=28) or experiencing regular natural menstrual cycles (n=26) completed step-wise menstrual mapping, urinary ovulation prediction testing and venous blood sampling for serum/plasma hormone analysis on two days, 6–12days after positive ovulation prediction to verify ovarian hormone concentrations. Mid-luteal phase was successfully verified in 100% of oral contraceptive users, and 70% of naturally-menstruating women. Thirty percent of participants were classified as luteal phase deficient; when excluded, the success of the method was 89%. Lower age, body fat and longer menstrual cycles were significantly associated with luteal phase deficiency. A step-wise method including menstrual cycle mapping, urinary ovulation prediction and serum/plasma hormone measurement was effective at verifying ovarian hormone status. Additional consideration of age, body fat and cycle length enhanced identification of luteal phase deficiency in physically-active women. These findings enable the development of stricter exclusion criteria for female participants in research studies and minimise the influence of ovarian hormone variations within sports and exercise science and medicine research.
International society of sports nutrition position stand: nutritional concerns of the female athlete
Based on a comprehensive review and critical analysis of the literature regarding the nutritional concerns of female athletes, conducted by experts in the field and selected members of the International Society of Sports Nutrition (ISSN), the following conclusions represent the official Position of the Society: 1. Female athletes have unique and unpredictable hormone profiles, which influence their physiology and nutritional needs across their lifespan. To understand how perturbations in these hormones affect the individual, we recommend that female athletes of reproductive age should track their hormonal status (natural, hormone driven) against training and recovery to determine their individual patterns and needs and peri and post-menopausal athletes should track against training and recovery metrics to determine the individuals' unique patterns. 2. The primary nutritional consideration for all athletes, and in particular, female athletes, should be achieving adequate energy intake to meet their energy requirements and to achieve an optimal energy availability (EA); with a focus on the timing of meals in relation to exercise to improve training adaptations, performance, and athlete health. 3. Significant sex differences and sex hormone influences on carbohydrate and lipid metabolism are apparent, therefore we recommend first ensuring athletes meet their carbohydrate needs across all phases of the menstrual cycle. Secondly, tailoring carbohydrate intake to hormonal status with an emphasis on greater carbohydrate intake and availability during the active pill weeks of oral contraceptive users and during the luteal phase of the menstrual cycle where there is a greater effect of sex hormone suppression on gluconogenesis output during exercise. 4. Based upon the limited research available, we recommend that pre-menopausal, eumenorrheic, and oral contraceptives using female athletes should aim to consume a source of high-quality protein as close to beginning and/or after completion of exercise as possible to reduce exercise-induced amino acid oxidative losses and initiate muscle protein remodeling and repair at a dose of 0.32-0.38 g·kg . For eumenorrheic women, ingestion during the luteal phase should aim for the upper end of the range due to the catabolic actions of progesterone and greater need for amino acids. 5. Close to the beginning and/or after completion of exercise, peri- and post-menopausal athletes should aim for a bolus of high EAA-containing (~10 g) intact protein sources or supplements to overcome anabolic resistance. 6. Daily protein intake should fall within the mid- to upper ranges of current sport nutrition guidelines (1.4-2.2 g·kg ·day ) for women at all stages of menstrual function (pre-, peri-, post-menopausal, and contraceptive users) with protein doses evenly distributed, every 3-4 h, across the day. Eumenorrheic athletes in the luteal phase and peri/post-menopausal athletes, regardless of sport, should aim for the upper end of the range. 7. Female sex hormones affect fluid dynamics and electrolyte handling. A greater predisposition to hyponatremia occurs in times of elevated progesterone, and in menopausal women, who are slower to excrete water. Additionally, females have less absolute and relative fluid available to lose via sweating than males, making the physiological consequences of fluid loss more severe, particularly in the luteal phase. 8. Evidence for sex-specific supplementation is lacking due to the paucity of female-specific research and any differential effects in females. Caffeine, iron, and creatine have the most evidence for use in females. Both iron and creatine are highly efficacious for female athletes. Creatine supplementation of 3 to 5 g per day is recommended for the mechanistic support of creatine supplementation with regard to muscle protein kinetics, growth factors, satellite cells, myogenic transcription factors, glycogen and calcium regulation, oxidative stress, and inflammation. Post-menopausal females benefit from bone health, mental health, and skeletal muscle size and function when consuming higher doses of creatine (0.3 g·kg ·d ). 9. To foster and promote high-quality research investigations involving female athletes, researchers are first encouraged to stop excluding females unless the primary endpoints are directly influenced by sex-specific mechanisms. In all investigative scenarios, researchers across the globe are encouraged to inquire and report upon more detailed information surrounding the athlete's hormonal status, including menstrual status (days since menses, length of period, duration of cycle, etc.) and/or hormonal contraceptive details and/or menopausal status.
The acute effect of the menstrual cycle and oral contraceptive cycle on measures of body composition
PurposeThis study aimed to investigate the effect of fluctuating female hormones during the menstrual cycle (MC) and oral contraceptive (OC) cycle on different measures of body composition.MethodsTwenty-two women with a natural MC and thirty women currently taking combined monophasic OC were assessed over three phases of the menstrual or oral contraceptive cycle. Body weight, skinfolds, bioelectric impedance analysis (BIA), ultrasound, dual-energy X-ray absorptiometry (DXA), and peripheral quantitative computed tomography (pQCT) measurements were performed to assess body composition. Urine specific gravity (USG) was measured as an indication of hydration, and serum oestradiol and progesterone were measured to confirm cycle phases.ResultsFive participants with a natural MC were excluded based on the hormone analysis. For the remaining participants, no significant changes over the MC and OC cycle were found for body weight, USG, skinfolds, BIA, ultrasound and pQCT measures. However, DXA body fat percentage and fat mass were lower in the late follicular phase compared to the mid-luteal phase of the MC, while for the OC cycle, DXA body fat percentage was higher and lean mass lower in the early hormone phase compared with the late hormone phase.ConclusionOur findings suggest that assessment of body fat percentage through BIA and skinfolds may be performed without considering the MC or OC cycle. Body adiposity assessment via DXA, however, may be affected by female hormone fluctuations and therefore, it may be advisable to perform repeat testing using DXA during the same phase of the MC or OC cycle.
The Effect of the Menstrual Cycle and Oral Contraceptive Cycle on Muscle Performance and Perceptual Measures
Most reproductive-aged women are exposed to fluctuating female steroid hormones due to the menstrual cycle or oral contraceptive use. This study investigated the potential effect of the menstrual cycle and combined monophasic oral contraceptive cycle on various aspects of muscle performance. Thirty active females (12 with a natural menstrual cycle, 10 taking a high-androgenicity oral contraceptive and 8 taking a low-androgenicity oral contraceptive), aged 18 to 30 years, were tested three times throughout one menstrual or oral contraceptive cycle. Counter-movement jumps, bilateral hop jumps, handgrip strength, isometric knee extensor strength and isokinetic knee flexion and extension were assessed. Perceptual ratings of fatigue, muscle soreness, pain and mood were recorded. Most variables showed no significant changes over the menstrual or oral contraceptive cycle. However, for the menstrual cycle group, isokinetic knee flexion at 240° s−1, and time of flight in bilateral hopping and counter movement jumps showed better results during the mid-luteal phase compared with the late follicular phase. For the high-androgenicity oral contraceptive group, isokinetic knee flexion at 240° s−1 was significantly higher in the late hormone phase compared with the early hormone phase. For the low-androgenicity oral contraceptive group, time of flight for the counter-movement jumps was lower in the late hormone phase compared with the early hormone phase. The findings indicate that faster and explosive aspects of muscle performance may be influenced by endogenous and exogenous female hormones.
Menstrual Cycle Phases Influence on Cardiorespiratory Response to Exercise in Endurance-Trained Females
The aim of this study was to analyse the impact of sex hormone fluctuations throughout the menstrual cycle on cardiorespiratory response to high-intensity interval exercise in athletes. Twenty-one eumenorrheic endurance-trained females performed an interval running protocol in three menstrual cycle phases: early-follicular phase (EFP), late-follicular phase (LFP) and mid-luteal phase (MLP). It consisted of 8 × 3-min bouts at 85% of their maximal aerobic speed with 90-s recovery at 30% of their maximal aerobic speed. To verify menstrual cycle phase, we applied a three-step method: calendar-based counting, urinary luteinizing hormone measurement and serum hormone analysis. Mixed-linear model for repeated measures showed menstrual cycle impact on ventilatory (EFP: 78.61 ± 11.09; LFP: 76.45 ± 11.37; MLP: 78.59 ± 13.43) and heart rate (EFP: 167.29 ± 11.44; LFP: 169.89 ± 10.62; MLP: 169.89 ± 11.35) response to high-intensity interval exercise (F2.59 = 4.300; p = 0.018 and F2.61 = 4.648; p = 0.013, respectively). Oxygen consumption, carbon dioxide production, respiratory exchange ratio, breathing frequency, energy expenditure, relative perceived exertion and perceived readiness were unaltered by menstrual cycle phase. Most of the cardiorespiratory variables measured appear to be impassive by menstrual cycle phases throughout a high-intensity interval exercise in endurance-trained athletes. It seems that sex hormone fluctuations throughout the menstrual cycle are not high enough to disrupt tissues’ adjustments caused by the high-intensity exercise. Nevertheless, HR based training programs should consider menstrual cycle phase.
Manual lymphatic drainage treatment for lymphedema: a systematic review of the literature
PurposeManual lymphatic drainage (MLD) massage is widely accepted as a conservative treatment for lymphedema. This systematic review aims to examine the methodologies used in recent research and evaluate the effectiveness of MLD for those at-risk of or living with lymphedema.MethodsThe electronic databases Embase, PubMed, CINAHL Complete and Cochrane Central Register of Controlled Trials were searched using relevant terms. Studies comparing MLD with another intervention or control in patients at-risk of or with lymphedema were included. Studies were critically appraised with the PEDro scale.ResultsSeventeen studies with a total of 867 female and two male participants were included. Only studies examining breast cancer-related lymphedema were identified. Some studies reported positive effects of MLD on volume reduction, quality of life and symptom-related outcomes compared with other treatments, while other studies reported no additional benefit of MLD as a component of complex decongestive therapy. In patients at-risk, MLD was reported to reduce incidence of lymphedema in some studies, while others reported no such benefits.ConclusionsThe reviewed articles reported conflicting findings and were often limited by methodological issues. This review highlights the need for further experimental studies on the effectiveness of MLD in lymphedema.Implications for Cancer SurvivorsThere is some evidence that MLD in early stages following breast cancer surgery may help prevent progression to clinical lymphedema. MLD may also provide additional benefits in volume reduction for mild lymphedema. However, in moderate to severe lymphedema, MLD may not provide additional benefit when combined with complex decongestive therapy.
The Effect of the Menstrual Cycle and Oral Contraceptives on Acute Responses and Chronic Adaptations to Resistance Training: A Systematic Review of the Literature
Background Resistance training is well known to increase strength and lean body mass, and plays a key role in many female athletic and recreational training programs. Most females train throughout their reproductive years when they are exposed to continuously changing female steroid hormone profiles due to the menstrual cycle or contraceptive use. Therefore, it is important to focus on how female hormones may affect resistance training responses. Objective The aim of this systematic review is to identify and critically appraise current studies on the effect of the menstrual cycle and oral contraceptives on responses to resistance training. Methods The electronic databases Embase, PubMed, SPORTDiscus and Web of Science were searched using a comprehensive list of relevant terms. Studies that investigated the effect of the menstrual cycle phase or oral contraceptive cycle on resistance training responses were included. Studies were also included if they compared resistance training responses between the natural menstrual cycle and oral contraceptive use, or if resistance training was adapted to the menstrual cycle phase or oral contraceptive phase. Studies were critically appraised with the McMasters Universities Critical Review Form for Quantitative Studies and relevant data were extracted. Results Of 2007 articles found, 17 studies met the criteria and were included in this systematic review. The 17 included studies had a total of 418 participants with an age range of 18–38 years. One of the 17 studies found no significant differences in acute responses to a resistance training session over the natural menstrual cycle, while four studies did find changes. When assessing the differences in acute responses between the oral contraceptive and menstrual cycle groups, two studies reported oral contraceptives to have a positive influence, whilst four studies reported that oral contraceptive users had a delayed recovery, higher levels of markers of muscle damage, or both. For the responses to a resistance training program, three studies reported follicular phase-based training to be superior to luteal phase-based training or regular training, while one study reported no differences. In addition, one study reported no differences in strength development between oral contraceptive and menstrual cycle groups. One further study reported a greater increase in type I muscle fibre area and a trend toward a greater increase in muscle mass within low-androgenic oral contraceptive users compared with participants not taking hormonal contraceptives. Finally, one study investigated androgenicity of oral contraceptives and showed greater strength developments with high androgenic compared with anti-androgenic oral contraceptive use. Conclusions The reviewed articles reported conflicting findings, and were often limited by small participant numbers and methodological issues, but do appear to suggest female hormones may affect resistance training responses. The findings of this review highlight the need for further experimental studies on the effects of the menstrual cycle and oral contraceptives on acute and chronic responses to resistance training.
UEFA consensus statement on menstrual cycle tracking in women’s football
Menstrual cycle tracking is increasingly recognised as an important aspect of supporting female athletes. However, its application in football remains inconsistent and under-researched. This consensus statement, initiated by the Union of European Football Associations Medical and Anti-Doping Unit, provides evidence-informed guidance on best practices for menstrual cycle tracking in women’s football. Developed using the RAND-UCLA appropriateness method, the consensus involved a multidisciplinary expert panel that reviewed the literature and reached agreement on 82 statements across five key domains: the rationale for tracking, meaningful metrics, appropriate methods, implementation strategies and methodological considerations for research. The consensus underscores that while current evidence linking menstrual cycle phases to performance or injury risk remains inconclusive, tracking can support athlete well-being by identifying menstrual irregularities, managing symptoms and enhancing player education and autonomy. Practical recommendations are provided for measuring cycle characteristics, ovulation, hormonal profiles and symptoms, whereas ethical and cultural considerations are emphasised. This statement aims to promote standardised, athlete-centred tracking protocols and establish priorities for practice and future research in female football.
Kinematics of the typical beach flags start for young adult sprinters
This study profiled beach flags start kinematics for experienced young adult sprinters. Five males and three females (age = 20.8 ± 2.1 years; height = 1.70 ± 0.06 meters [m]; mass = 63.9 ± 6.0 kilograms) completed four sprints using their competition start technique. A high-speed camera, positioned laterally, filmed the start. Data included: start time; hand clearance time; posterior movement from the start line; feet spacing during the start; elbow, hip, knee, trunk lean, and trajectory angles at take-off; and first step length. Timing gates recorded 0-2, 0-5, and 0-20 m time. Spearman's correlations identified variables relating (p ≤ 0.05) to faster start and sprint times. The beach flags start involved sprinters moving 0.18 ± 0.05 m posterior to the start line by flexing both legs underneath the body before turning. Following the turn, the feet were positioned 0.47 ± 0.07 apart. This distance negatively correlated with start (ρ = -0.647), 0-2 (ρ = -0.683), and 0-5 m (ρ = -0.766) time. Beach flags start kinematics at take-off resembled research analyzing track starts and acceleration. The elbow extension angle (137.62 ± 13.45°) of the opposite arm to the drive leg correlated with 0-2 (ρ = -0.762), 0-5 (ρ = -0.810), and 0-20 m (ρ = -0.810) time. Greater arm extension likely assisted with stability during the start, leading to enhanced sprint performance. The drive leg knee extension angle (146.36 ± 2.26°) correlated with start time (ρ = -0.677), indicating a contribution to a faster start completion. A longer first step following the start related to faster 0-5 m time (ρ = -0.690). Sprinters quicker over 0-2 and 0-5 m were also quicker over 20 m (ρ = 0.881-0.952). Beach flags sprinters must ensure their start is completed quickly, such that they can attain a high speed throughout the race. Key pointsThere are specific movement patterns adopted by beach flags sprinters during the start. Sprinters will move posterior to the start time prior to turning. Following the turn, sprinters must position their feet such that force output is optimized and low body position at take-off can be attained.The body position at take-off from the beach flags start is similar to that of established technique parameters for track sprinters leaving starting blocks, and field sport athletes during acceleration. A greater range of motion at the arms can aid with stability during the turn and at take-off from the start. Greater knee extension of the drive leg at take-off can assist with reducing the duration of the start.The beach flags start must allow for a quick generation of speed through the initial stages of the sprint, as this can benefit the later stages. A longer first step following the start can help facilitate speed over the initial acceleration period. Beach flags sprinters must also attempt to maintain their speed throughout the entirety of the race.
Restriction in lateral bending range of motion, lumbar lordosis, and hamstring flexibility predicts the development of low back pain: a systematic review of prospective cohort studies
Background Low back pain (LBP) is an increasingly common condition worldwide with significant costs associated with its management. Identification of musculoskeletal risk factors that can be treated clinically before the development of LBP could reduce costs and improve the quality of life of individuals. Therefore the aim was to systematically review prospective cohort studies investigating lower back and / or lower limb musculoskeletal risk factors in the development of LBP. Methods MEDLINE, EMBASE, AMED, CINAHL, SPORTDiscus, and the Cochrane Library were searched from inception to February 2016. No age, gender or occupational restrictions of participants were applied. Articles had to be published in English and have a 12 month follow-up period. Musculoskeletal risk factors were defined as any osseous, ligamentous, or muscular structure that was quantifiably measured at baseline. Studies were excluded if participants were pregnant, diagnosed with cancer, or had previous low back surgery. Two authors independently reviewed and selected relevant articles. Methodological quality was evaluated independently by two reviewers using a generic tool for observational studies. Results Twelve articles which evaluated musculoskeletal risk factors for the development of low back pain in 5459 participants were included. Individual meta-analyses were conducted based on risk factors common between studies. Meta-analysis revealed that reduced lateral flexion range of motion (OR = 0.41, 95% CI 0.24-0.73, p  = 0.002), limited lumbar lordosis (OR = 0.73, 95% CI 0.55-0.98, p  = 0.034), and restricted hamstring range of motion (OR = 0.96, 95% CI 0.94-0.98, p  = 0.001) were significantly associated with the development of low back pain. Meta-analyses on lumbar extension range of motion, quadriceps flexibility, fingertip to floor distance, lumbar flexion range of motion, back muscle strength, back muscle endurance, abdominal strength, erector spinae cross sectional area, and quadratus lumborum cross sectional area showed non-significant results. Conclusion In summary, we found that a restriction in lateral flexion and hamstring range of motion as well as limited lumbar lordosis were associated with an increased risk of developing LBP. Future research should aim to measure additional lower limb musculoskeletal risk factors, have follow up periods of 6-12 months, adopt a standardised definition of LBP, and only include participants who have no history of LBP.