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Robles-Cerdas, V.

Publications and source records attributed to Robles-Cerdas, V..

2 recordsLinked to original sources
bioRxiv2026

Does Balance Vary Across the Menstrual Cycle?: A Meta-Analysis with Implications for Women's Health.

Background: Women remain underrepresented across many domains of research, clinical science, and medicine. Sex differences other than the reproductive system, body composition, and size, are poorly understood. The menstrual cycle, for example, can be influenced using hormonal contraception methods. Hormonal fluctuations through the menstrual cycle go beyond the reproductive physiology and influence systems involved in balance and postural control. Data Sources and Methods: The search was conducted through the following databases: PubMed, Web of Science, Medline, SPORTDiscus and Scopus (up to March 6, 2026) for studies that looked for the effects of the menstrual cycle phases on balance in women using or not hormonal contraceptives. Standardized mean difference was used to estimate the effect of menstrual cycle phases on postural control and Hedges' g was reported to account for the small sample bias. Two multilevel mixed effects models, meta-regression, and sensitivity analyses were conducted. The funnel plot was used to determine if there was a publication bias. Thirteen studies were included in this meta-analysis. Results: For static balance tasks, the pooled effect size was small and not statistically significant (SMDH = -0.19, 95% CI = -0.41 - 0.02, p = .073). Similarly, no significant effect observed for dynamic balance tasks (SMDH = 0.18, 95% CI = -0.67 - 1.04, p = .44). The moderator analyses showed that contraceptive use did not significantly explain the variability in either static or dynamic balance outcomes. Conclusions: This meta-analysis demonstrated that current evidence does not establish a consistent effect of menstrual cycle phase on static or dynamic balance. High-quality studies with standardized menstrual cycle verification methods are needed to clarify the relationship between hormonal fluctuations and postural control in women. Registration: PROSPERO CRD420261402114. Keywords: Balance, postural sway, hormonal fluctuations, menstrual cycle phases, hormonal contraceptives.

neuroscience↗
bioRxiv2026

Acute molecular and chronic vastus lateralis adaptations to lengthened partial versus full range of motion resistance training in previously trained males

This study examined how lower-body lengthened partial (LP) versus full range of motion (FULL) resistance training affects acute post-exercise signaling, chronic hypertrophy, and cellular adaptations of the vastus lateralis (VL) muscle in resistance-trained men. Eight males (22{+/-}1 years old, 5.6{+/-}1.4 years training) completed a crossover study whereby VL biopsies were collected pre-exercise and 0, 3, and 24 hours following LP and FULL leg extension bouts for transcriptomic and anabolic signaling analyses (Experiment 1). Another 16 males (26{+/-}5 years old; 8.0{+/-}4.9 years training) completed an 8-week, twice-weekly lower-body intervention using a within-subject design (Experiment 2). One leg was assigned to FULL and the contralateral leg to LP training across three exercises (leg press, leg extension, and lying leg curl). Pre- and post-intervention outcomes included VL muscle cross-sectional area (mCSA) summed across five equidistant MRI-derived transverse slices and mid-thigh VL biopsy outcomes. As a secondary outcome, other hip and thigh muscles from Experiment 2 MRI scans were assessed. Condition x Time interactions for all outcomes were assessed using linear mixed-effects models. In Experiment 1, both conditions produced similar time-dependent changes in the VL transcriptome and anabolic (mTORC1 and Hippo) signaling, but minimal between-protocol interactions. In Experiment 2, VL summed mCSA significantly increased over time (mean change: 9.3 cm{superscript 2}, 95% CI [6.8, 11.8], P<0.001), but there was no clear evidence of differential change between protocols (LP-FULL change: -1.4 cm{superscript 2}, 95% CI [-6.1, 3.8], P=0.640). Additionally, no significant interactions existed for type I fiber CSA (P=0.476), type II fiber CSA (P=0.350), type I fiber myonuclei (P=0.813), type II fiber myonuclei (P=0.589), type I and II satellite cell number (P=0.102 and P=0.797, respectively), or total RNA content (P=0.537). Despite these null VL-centric findings, secondary Experiment 2 analyses provided some evidence that whole hamstring hypertrophy was greater following LP versus FULL (LP-FULL change: 3.9 cm{superscript 2}, 95% CI [-0.2, 7.9], P=0.058). In conclusion, 8 weeks of LP and FULL resistance training broadly elicit similar acute and chronic VL responses in previously trained men, though secondary hamstring findings suggest that differential responses may depend on exercises included in the resistance training program.

physiology↗