Assessing Trail Running Biomechanics: A Comparative Analysis of the Reliability of StrydTM and GARMINRP Wearable Devices.

This study investigated biomechanical assessments in trail running, comparing two wearable devices-Stryd Power Meter and GARMINRP. With the growing popularity of trail running and the complexities of varied terrains, there is a heightened interest in understanding metabolic pathways, biomechanics, and performance factors. The research aimed to assess the inter- and intra-device agreement for biomechanics under ecological conditions, focusing on power, speed, cadence, vertical oscillation, and contact time. The participants engaged in trail running sessions while wearing two Stryd and two Garmin devices. The intra-device reliability demonstrated high consistency for both GARMINRP and StrydTM, with strong correlations and minimal variability. However, distinctions emerged in inter-device agreement, particularly in power and contact time uphill, and vertical oscillation downhill, suggesting potential variations between GARMINRP and StrydTM measurements for specific running metrics. The study underscores that caution should be taken in interpreting device data, highlighting the importance of measuring with the same device, considering contextual and individual factors, and acknowledging the limited research under real-world trail conditions. While the small sample size and participant variations were limitations, the strength of this study lies in conducting this investigation under ecological conditions, significantly contributing to the field of biomechanical measurements in trail running.

Changes in Baropodometric Evaluation and Discomfort during the Workday in Assembly-Line Workers.

Prolonged standing at work is associated with health risks. The appearance of lower-limb and lower-back discomfort is one of the most prevalent factors in prolonged standing workers. The aim of this research was to evaluate the effect of an eight-hour workday on foot pressure and musculoskeletal discomfort in standing workers. Thirty-six assembly-line workers (six women) were recruited to participate in a cross-sectional study to assess foot pressure and surface, foot, knee, and lower-back discomfort before and after a real workday. Baropodometry outcomes (surface and pressure) were evaluated by the pressure platform SensorMedica and musculoskeletal discomfort was evaluated by Cornell's Musculoskeletal Discomfort Questionaire. Total foot surface (p = 0.01) and foot discomfort (p = 0.03) increased significantly at the end of the workday. Prolonged standing during 8 h workday increased the foot discomfort and total foot surface in assembly-line workers. No foot pressure variable (forefoot, rearfoot, or total) was significantly modified after the workday in assembly-line workers.

Running Economy in the Vertical Kilometer.

New and promising variables are being developed to analyze performance and fatigue in trail running, such as mechanical power, metabolic power, metabolic cost of transport and mechanical efficiency. The aim of this study was to analyze the behavior of these variables during a real vertical kilometer field test. Fifteen trained trail runners, eleven men (from 22 to 38 years old) and four women (from 19 to 35 years old) performed a vertical kilometer with a length of 4.64 km and 835 m positive slope. During the entire race, the runners were equipped with portable gas analyzers (Cosmed K5) to assess their cardiorespiratory and metabolic responses breath by breath. Significant differences were found between top-level runners versus low-level runners in the mean values of the variables of mechanical power, metabolic power and velocity. A repeated-measures ANOVA showed significant differences between the sections, the incline and the interactions between all the analyzed variables, in addition to differences depending on the level of the runner. The variable of mechanical power can be statistically significantly predicted from metabolic power and vertical net metabolic COT. An algebraic expression was obtained to calculate the value of metabolic power. Integrating the variables of mechanical power, vertical velocity and metabolic power into phone apps and smartwatches is a new opportunity to improve performance monitoring in trail running.

Visual Perception in Expert Athletes: The Case of Rock Climbers.

The purpose of the present study was to examine the visual perception system in expert climbers through a psychophysical optical test in a cross-sectional study. Twenty-seven male participants with an International Rock Climbing Research Association (IRCRA) best on-sight lead skill level ranging between 18 and 27 and a best red-point level ranging between 18 and 29 completed a series of psychophysical optic tests assessing their visual field, visual acuity, and contrast sensitivity. Climbers were divided by their best red-pointed lead level, and, following IRCRA recommendations, two groups were created: an advanced group (IRCRA redpoint level between 18 and 23), and an elite-high elite group (IRCRA redpoint level between 24 and 29). The elite group presented more training days per week (5.25 ± 1.28), best on-sighted lead level (24.63 ± 1.92 IRCRA), and best red-pointed lead level (26.63 ± 2.56 IRCRA) than the advanced group (3.67 ± 0.91 training days per week, 19.50 ± 1.04 IRCRA on-sighted level and 20.67 ± 1.57 IRCRA red-pointed level). Better visual perception outputs were produced by the group of elite climbers in visual field tests; no differences were observed between the two groups for visual acuity and contrast sensitivity tests. Overall, findings indicate that best climbers performed better at the visual perception tasks that tested their visual field. Such better perception from best climbers is discussed given (1) the greater time they spend coercing the visual system during practicing climbing and (2) the specific complexity of the stimuli as they are confronted to harder routes where holds are less perceptible and the time to find best hold sequences is constrained.

Spinal sagittal alignment, spinal shrinkage and back pain changes in office workers during a workday.

Purpose. Prolonged sitting is a risk factor for the appearance of lower back pain during work. The aim of this study was to observe changes in spinal sagittal alignment, height and the perception of back pain in office workers during a workday. Materials and methods. Forty-one office workers (20 women) were enrolled into a cross-sectional study. Height, sitting height and degrees of thoracic kyphosis and lumbar lordosis as well as perceived neck pain, lower back pain and upper back pain were determined, before and after an 8-h workday. Results. At the end of the day, workers had a significant decrease (p = 0.000) in height and sitting height, and upper back pain increased significantly (p = 0.023). In men, spinal shrinkage correlated with neck pain (r = 0.410, p = 0.027), and lumbar lordosis degrees in women correlated negatively with upper back pain at the end of the day (r = -0.440, p = 0.012). Conclusions. Spinal shrinkage equally affects men and women who perform the same work. There are no changes in spinal sagittal alignment throughout the workday in office workers. Office workers show significantly increased pain in the upper back at the end of the day.

Use of a Spinal Traction Device during Work Shift in Assembly Line Workers.

Increasing back discomfort and spinal shrinkage during the workday is a problem that affects assembly line workers. The aim of this research was to analyze the effect of a spinal traction system on discomfort, spinal shrinkage, and spinal sagittal alignment in assembly line workers, who are in prolonged standing conditions during a workday. A total of 16 asymptomatic males were recruited to assess spinal shrinkage, spinal sagittal alignment, and back discomfort during the workday. The measurement was carried out in two days of work, a normal day, and the other using a spinal traction device utilized in two breaks during the workday. Assembly line workers lost height significantly on both control and intervention days. No differences were found between days. No changes were found in spinal sagittal alignment on the control day. Lumbar lordosis angle increased significantly at the end of the intervention day. The use of a spinal traction device during the workday in two breaks time did not significantly reduce the spinal shrinkage of healthy workers. Lumbar lordosis angle increased significantly at the end of the spinal traction intervention day. Prospective studies would be necessary to clarify the possible benefits of the traction device.

Assessment of Spinal Range of Motion and Musculoskeletal Discomfort in Forklift Drivers. A Cross-Sectional Study.

Forklifts are commonly used in industrial supply chains to transport heavy loads. Forklift drivers have the risk of developing musculoskeletal discomfort derived from the movement pattern required at work. This research aimed to investigate the spinal range of motion (ROM) and musculoskeletal discomfort of forklift drivers and compare it with a control group. Forklift drivers (39 males) and office workers (31 males) were recruited to assess cervical, thoracic, and lumbar ROM with an electronic double inclinometer. Additionally, musculoskeletal discomfort was registered with the Cornell Discomfort Musculoskeletal Questionnaire. Forklift drivers showed a higher cervical discomfort and ROM of lateral lumbar bending than office workers. Both groups reported lower ROM in cervical and lumbar lateral bending on the right side versus the left side. No differences of asymmetry were reported for any variable between groups. Specific exercise programs may correct these mobility imbalances.

Muscle Tone and Body Weight Predict Uphill Race Time in Amateur Trail Runners.

BACKGROUND: Vertical kilometer is an emerging sport where athletes continuously run uphill. The aims of this study were to assess changes in vertical impacts caused by uphill running (UR) and the relation between the anthropometric and lower limb muscular characteristics with speed. METHODS: Ten male experienced runners (35 ± 7 years old) participated in this study. In the racetrack (4.2 km long, 565 m high), seven sections were stablished. Mean speed and impact value of sections with similar slope (≈21%) were calculated. The gastrocnemius stiffness (GS) and tone (GT); and the vastus lateralis stiffness (VS) and tone (VT) were assessed before the race. RESULTS: Pearson's correlation showed a linear relationship between vs. and VT (r = 0.829; p = 0.000), GT and GS (r = 0.792; p = 0.001). Mean speed is correlated with weight (r = -0.619; p = 0.024) and GT (r = 0.739; p = 0.004). Multiple linear regressions showed a model with weight and GT as dependent variables of mean speed. Mean impacts decreased significantly between sections along the race. CONCLUSIONS: The vertical impacts during UR were attenuated during the race. Moreover, body weight and GT were associated with the time-to-finish, which supports that low weight alone could not be enough to be faster, and strength training of plantar flexors may be a determinant in UR.

Modifications of viscoelastic properties and physiological parameters after performing uphill and downhill running trials.

BACKGROUND: Trail running performance depends on many factors, including energy cost of running, biomechanical parameters and stiffness. The aim of this study was to examine the influence of different positive and negative slopes on metabolic cost, tight hemoglobin saturation, viscoelastic properties, and vertical peak impacts in physically active young runners. METHODS: Nine healthy male volunteers (26±5 years) performed two separate uphill and downhill sessions on an instrumented treadmill; both sessions were completed in a random order at a constant running speed with variable slopes from 0% to ±20%. Oxygen uptake (V̇O2), carbon dioxide production (V̇CO2), pulmonary ventilation (V̇E), respiratory exchange ratio, heart rate (HR), muscle oxygen saturation, vertical impacts, and muscle tone and stiffness were assessed. RESULTS: During downhill running, V̇O2peak and V̇CO2 significantly decreased, and impacts higher than 6G significantly increased with a negative slope. During uphill running, V̇O2peak, V̇CO2, V̇E, and maximum HR significantly increased. Minimum values of oxygen saturation and the vastus medialis tone significantly decreased and impacts of 4-5 G significantly increased with a positive slope. CONCLUSIONS: Metabolic demand increased proportionally with the uphill slope and showed a linear negative relationship with a light and moderate downhill slope. Vertical impacts of high G-forces increased during downhill running, data that indicate the importance of our ability to attenuate impacts. Finally, muscle tone and stiffness remained stable at all times, results that demonstrated their acute adaptation to running in the absence of extreme fatigue.

Adapted exercises versus general exercise recommendations on chronic low back pain in industrial workers: A randomized control pilot study.

BACKGROUND: Exercise has been demonstrated as effective for the treatment of low back pain (LBP) in workers. OBJECTIVE: The purpose of this study was to investigate whether an exercise program adapted to the characteristics of the workplace is a useful supplement to general exercise recommendations in assembly line workers with chronic LBP. METHODS: Workers were randomly assigned to intervention group-adapted exercises plus general exercise recommendations (n = 10), and control group-general exercise recommendations (n = 8). Both received 8-week exercise program through a mobile application (APP) to manage the intervention. Outcome was based on lumbar disability (Oswestry Disability Index), interference and lumbar pain intensity (Brief Pain Inventory), and kinematic parameters. RESULTS: Significant differences were obtained for the intervention group in the "pain interference" variable, in the "mood" and "enjoyment" sub-variables, as well as in "flexion angle" variable. For the control group, significant differences occurred in the "pain intensity" variable. Adapted exercise plus general recommendations seems more effective than the general recommendations for the improvement of lumbar flexion. CONCLUSIONS: An adapted exercise program for assembly line workers with chronic LBP could be an effective treatment. Future studies with a larger sample size and with an exhaustive control of the exercise adherence are required to confirm the findings of this pilot study.

Static Balance Modification during the Workday in Assembly Chain Workers with and without Current Low Back Pain.

BACKGROUND: Low back pain (LBP) is a common recurrent pathology among assembly chain workers. This population tends to spend most of the workday in a static standing posture and handling loads, with balance being essential for correct job performance. LBP is related to poorer postural control, so balance could be affected in this condition. METHODS: The purpose of the present study is to analyze the deterioration of static balance generated by work activity in a prolonged standing position. We assess sway with a pressure platform at three moments of the workday (before, during, and after work), comparing the different balance parameters in 22 manufacturing plant workers with (17) and without (5) LBP. RESULTS: In the pre-work capture, an independent t-test showed no significant differences between the pain and non-pain groups' static balance parameters. Between the pre- and mid-workday captures, a two-way ANOVA with repeated measures showed a significant decrease in the medial-lateral center of pressure displacement with open eyes in workers with LBP. CONCLUSIONS: workers with low back pain do not show a greater deterioration in static balance than workers without pain during the workday.

Combined Preimplantation Genetic Testing for Autosomal Dominant Polycystic Kidney Disease: Consequences for Embryos Available for Transfer.

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary kidney disease and presents with genetic and clinical heterogeneity. ADPKD can also manifest extra-renally, and seminal cysts have been associated with male infertility in some cases. ADPKD-linked male infertility, along with female age, have been proposed as factors that may influence the clinical outcomes of preimplantation genetic testing (PGT) for monogenic disorders (PGT-M). Large PGT for aneuploidy assessment (PGT-A) studies link embryo aneuploidy to increasing female age; other studies suggest that embryo aneuploidy is also linked to severe male-factor infertility. We aimed to assess the number of aneuploid embryos and the number of cycles with transferable embryos in ADPKD patients after combined-PGT. The combined-PGT protocol, involving PGT-M by PCR and PGT-A by next-generation sequencing, was performed in single trophectoderm biopsies from 289 embryos in 83 PGT cycles. Transferable embryos were obtained in 69.9% of cycles. The number of aneuploid embryos and cycles with transferable embryos did not differ when the male or female had the ADPKD mutation. However, a significantly higher proportion of aneuploid embryos was found in the advanced maternal age (AMA) group, but not in the male factor (MF) group, when compared to non-AMA and non-MF groups, respectively. Additionally, no significant differences in the percentage of cycles with transferable embryos were found in any of the groups. Our results indicate that AMA couples among ADPKD patients have an increased risk of aneuploid embryos, but ADPKD-linked male infertility does not promote an increased aneuploidy rate.

Comparative study of treatment interventions for patellar tendinopathy: a protocol for a randomised controlled trial.

INTRODUCTION: Patellar tendinopathy is a degenerative disease of the patellar tendon, which affects athletes from a variety of sports, and is especially predominant in sports involving high-impact jumping. The aim of this study is to determine the additional effect of two interventions combined with eccentric exercise and compare which one is the most effective at short-term and long-term follow-up for patients with patellar tendinopathy. METHODS AND ANALYSIS: This study is a randomised controlled trial with blinded participants. Measurements will be carried out by a specially trained blinded assessor. A sample of 57 patients with a medical diagnosis of patellar tendinopathy will participate in this study and will be divided into three treatment groups. Eligible participants will be randomly allocated to receive either: (a) treatment group with percutaneous needle electrolysis, (b) treatment group with dry needling or (c) treatment group with placebo needling. In addition, all groups will perform eccentric exercise. Functionality and muscle strength parameters, pain, ultrasound appearances and patient perceived quality of life shall be evaluated using the Victorian Institute of Sports Assessment for patellar (VISA-P), jump tests, Visual Analogue Scale, ultrasound images and Short Form-36 (SF-36), respectively. Participants will be assessed at baseline, at 10 weeks and at 22 weeks after baseline. The expected findings will allow us to advance in the treatment of this injury, as they will help determine whether a needling intervention has additional effects on an eccentric exercise programme and whether any of the needling modalities is more effective than the other. ETHICS AND DISSEMINATION: This protocol has been approved by the Ethics Committee of Aragon (N° PI15/0017). The trial will be conducted in accordance with the Declaration of Helsinki. TRIAL REGISTRATION NUMBER: NCT02498795.

Spinal shrinkage, sagittal alignment and back discomfort changes in manufacturing company workers during a working day.

Prolonged standing and lifting heavy loads are risk factors for the appearance of low back pain in work. The aim of this study was to observe changes in the height, spinal sagittal alignment, and the lumbar and dorsal discomfort perception in assembly line workers. Cross-sectional study, 40 assembly line workers (6 females). Height, sitting height, grades of thoracic kyphosis and lumbar lordosis and perceived spine discomfort, before and after the working day, were determined. Thoracic and lumbar sagittal alignment was compared between discomfort developers and no developers. There was a significant decrease in the height and sitting height of the workers at the end of the day. Thoracic and lumbar curvature increased significantly, as did the perceived lumbar discomfort. Workers on the assembly line, in a prolonged standing work, suffer an increase in lumbar discomfort, and changes in height and thoracic and lumbar curvatures. Practitioner summary: Spinal shrinkage, sagittal alignment and back discomfort (upper and lower back), were analysed in assembly line workers in prolonged standing during a workday. Assembly line workers suffer a decrease in height, an increase in their thoracic and lumbar curvature, and in lumbar discomfort throughout their workday.

Effectiveness of lumbar supports in low back functionality and disability in assembly-line workers.

Low back pain (LBP) is a common problem in manufacturing workers. Several strategies have been proposed in order to reduce the pain and/or improve functionality. Among them, lumbar supports are a common solution prescribed for lumbar pain relief. Most of the studies in the literature only consider subjective sensations of the workers for evaluation assessment. This study applies biomechanical tests (a flexion-relaxation test and a functional movement evaluation test) to analyse the effectiveness of flexible lumbar supports in functionality and disability versus placebo intervention, consisting of kinesiotape placed on the low back without any stress. 28 workers participated in the study, randomised in control and intervention groups with a two months' intervention. None of the biomechanical tests showed statistical differences in between-groups pre-post changes. No benefits of wearing a flexible lumbar support during the workday have been found in these assembly-line workers versus placebo intervention.

Effects of different percentages of body weight support on spatiotemporal step characteristics during running.

This study aimed to determine the effect of different percentages of body weight support (BWS) on spatiotemporal step characteristics during running. 26 endurance runners (age: 37 ± 9 years) completed a running treadmill protocol consisting of 6 different conditions (BWS combinations: 0-50%), with velocity maintained at 12 km/h. Each condition lasted 1 minute. Step angle, ground contact time (CT), flight time (FT), step length (SL) and frequency (SF), and duration of phases during stance time (phase1: initial contact; phase2: midstance; phase3: propulsion) were measured for every step during the test using a photoelectric cell system. Compared with the baseline condition (100% BW), FT was longer, CT was shorter, SL was longer, SF was lower, and the step angle was higher with each increase in BWS (p < 0.05). Also, some changes were observed in the duration of phases during stance time: phase1 did not experience changes across experimental conditions (p = 0.096), phase2 decreased and phase3 increased as BW was supported (p < 0.05). These results indicate that as BW was supported, runners showed longer FT and SL, shorter CT, lower SF, and greater step angle as well as some changes in the phases during the ground contact. Therefore, this study highlights the effect of different percentages of BWS on spatiotemporal parameters.

Lack of Influence of Muscular Performance Parameters on Spatiotemporal Adaptations With Increased Running Velocity.

Roche-Seruendo, LE, García-Pinillos, F, Haicaguerre, J, Bataller-Cervero, AV, Soto-Hermoso, VM, and Latorre-Román, PÁ. Lack of influence of muscular performance parameters on spatiotemporal adaptations with increased running velocity. J Strength Cond Res 32(2): 409-415, 2018-This study aimed to analyze the influence of muscular performance parameters on spatiotemporal gait characteristics during running when gradually increasing speed. Fifty-one recreationally trained male endurance runners (age, 28 ± 8 years) voluntarily participated in this study. Subjects performed a battery of jumping tests (squat jump, countermovement jump, and 20-cm drop jump), and after that, the subjects performed an incremental running test (10-20 km·h) on a motorized treadmill. Spatiotemporal parameters were measured using the OptoGait system. Cluster k-means analysis grouped subjects according to the jumping test performance, by obtaining a group of good jumpers (n = 19) and a group of bad jumpers (n = 32). With increased running velocity, contact time was shorter and flight time and step length were longer, whereas cadence and stride angle were greater (p < 0.001). No significant differences between groups (p ≥ 0.05) were found at any running speed. The results obtained indicate that increased running velocity produced no differences in spatiotemporal adaptations between those runners with good jumping ability and those with poor jumping ability. Based on that, it seems that muscular performance parameters do not play a key role in spatiotemporal adaptations experienced by recreational endurance runners with increased velocity. However, taken into consideration the well-known relationship between running performance and neuromuscular performance, the authors suggest that muscular performance parameters would be much more determinant in the presence of fatigue (exhausted condition) or in the case of considering other variables such as running economy or kinetic.

The impact of next-generation sequencing technology on preimplantation genetic diagnosis and screening.

Largely because of efforts required to complete the Human Genome Project, DNA sequencing has undergone a steady transformation with still-ongoing developments of high-throughput sequencing machines for which the cost per reaction is falling drastically. Similarly, the fast-changing landscape of reproductive technologies has been improved by genetic approaches. Preimplantation genetic diagnosis and screening were established more than two decades ago for selecting genetically normal embryos to avoid inherited diseases and to give the highest potential to achieve stable pregnancies. Most recent additions to the IVF practices (blastocyst/trophectoderm biopsy, embryo vitrification) and adoption of new genetics tools such as array comparative genome hybridization have allowed setting up more precise and efficient programs for clinical embryo diagnosis. Nevertheless, there is always room for improvements. Remarkably, a recent explosion in the release of advanced sequencing benchtop platforms, together with a certain maturity of bioinformatics tools, has set the target goal of sequencing individual cells for embryo diagnosis to be a realistically feasible scenario for the near future. Next-generation sequencing technology should provide the opportunity to simultaneously analyze single-gene disorders and perform an extensive comprehensive chromosome screening/diagnosis by concurrently sequencing, counting, and accurately assembling millions of DNA reads.

Proprotein convertase 5/6 is critical for embryo implantation in women: regulating receptivity by cleaving EBP50, modulating ezrin binding, and membrane-cytoskeletal interactions.

Establishment of endometrial receptivity is vital for successful embryo implantation; its failure causes infertility. Epithelial receptivity acquisition involves dramatic structural changes in the plasma membrane and cytoskeleton. Proprotein convertase 5/6 (PC6), a serine protease of the proprotein convertase (PC) family, is up-regulated in the human endometrium specifically at the time of epithelial receptivity and stromal cell decidualization. PC6 is the only PC member tightly regulated in this manner. The current study addressed the importance and mechanisms of PC6 action in regulating receptivity in women. PC6 was dysregulated in the endometrial epithelium during the window of implantation in infertile women of three demographically different cohorts. Its critical role in receptivity was evidenced by a significant reduction in mouse blastocyst attachment of endometrial epithelial cells after PC6 knockdown by small interfering RNA. Using a proteomic approach, we discovered that PC6 cleaved the key scaffolding protein, ezrin-radixin-moesin binding phosphoprotein 50 (EBP50), thereby profoundly affecting its interaction with binding protein ezrin (a key protein bridging actin filaments and plasma membrane), EBP50/ezrin cellular localization, and cytoskeleton-membrane connections. We further validated this novel PC6 regulation of receptivity in human endometrium in vivo in fertile vs. infertile patients. These results strongly indicate that PC6 plays a key role in regulating fundamental cellular remodeling processes, such as plasma membrane transformation and membrane-cytoskeletal interface reorganization. PC6 cleavage of a crucial scaffolding protein EBP50, thereby profoundly regulating membrane-cytoskeletal reorganization, greatly extends the current knowledge of PC biology and provides substantial new mechanistic insight into the fields of reproduction, basic cellular biology, and PC biochemistry.

Human endometrial CD98 is essential for blastocyst adhesion.

BACKGROUND: Understanding the molecular basis of embryonic implantation is of great clinical and biological relevance. Little is currently known about the adhesion receptors that determine endometrial receptivity for embryonic implantation in humans. METHODS AND PRINCIPAL FINDINGS: Using two human endometrial cell lines characterized by low and high receptivity, we identified the membrane receptor CD98 as a novel molecule selectively and significantly associated with the receptive phenotype. In human endometrial samples, CD98 was the only molecule studied whose expression was restricted to the implantation window in human endometrial tissue. CD98 expression was restricted to the apical surface and included in tetraspanin-enriched microdomains of primary endometrial epithelial cells, as demonstrated by the biochemical association between CD98 and tetraspanin CD9. CD98 expression was induced in vitro by treatment of primary endometrial epithelial cells with human chorionic gonadotropin, 17-ß-estradiol, LIF or EGF. Endometrial overexpression of CD98 or tetraspanin CD9 greatly enhanced mouse blastocyst adhesion, while their siRNA-mediated depletion reduced the blastocyst adhesion rate. CONCLUSIONS: These results indicate that CD98, a component of tetraspanin-enriched microdomains, appears to be an important determinant of human endometrial receptivity during the implantation window.