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- Acute effects of dynamic stretching on knee joint position sense and dynamic balance in recreational runners: A randomized controlled trialPublication . Simões, Edgar; Tavares, Nuno; Saraiva, MarinaObjectives: Proprioception and dynamic balance are crucial elements of neuromuscular control during running, supporting movement precision and postural adjustments. Dynamic stretching is commonly used in warm-ups to enhance muscle activation and sensorimotor readiness, but its acute effects on proprioception and balance remain unclear. Design: Randomized controlled trial. Participants: Sixty-two healthy recreational runners (25–45 years; ≥20 km/week), randomly assigned to a Dynamic Stretching group (n = 31) or a control group performing light walking (n = 31). Main outcome measures: Joint position sense was assessed through active joint repositioning using 2D video analysis, with Absolute Angular Error, Relative Angular Error, and Variable Angular Error as outcomes. Balance was evaluated using the Y-Balance Test, including anterior, posteromedial, and posterolateral reach directions, as well as a composite score. Results: The Dynamic Stretching group showed significant reductions in Absolute Angular Error (p < 0.05) and Variable Angular Error (p < 0.001), with a between-group difference in Relative Angular Error (p = 0.043). Both groups improved Y-Balance Test scores, but the Dynamic stretching group achieved significantly greater gains in posteromedial reach and Composite Score (p < 0.001). Conclusions: Dynamic stretching acutely improves proprioceptive accuracy and dynamic balance in recreational runners, supporting its inclusion in warm-up routines.
- Non-lethal heat shock induces cross-tolerance to different stressors in two strains of Brachionus koreanus (Rotifera: Monogononta): Mechanisms of increased tolerance to hydrogen peroxidePublication . Granada, Luana; Morão, Inês F.C.; Lemos, Marco F. L.; Bossier, Peter; Novais, Sara C.The rotifer Brachionus sp. is of great importance for aquaculture, as the reproduction cycle under rearing conditions of many economically important species larvae depends on the use of rotifers as first live feed. Establishing a protocol that results in an improved tolerance of rotifers to environmental stressors will allow for a more stable rotifer production. The exposure to non-lethal heat shocks (NLHS) already proved to enhance the tolerance, not only to heat stress, but also to other stressors in several aquatic species, by activating the heat shock response and epigenetic mechanisms. This study aimed to determine the potential of a single NLHS to induce tolerance to different abiotic stressors in two strains of B. koreanus (MRS10 and IBA3) and to evaluate possible molecular mechanisms involved in the achievement of increased tolerance to hydrogen peroxide induced by NLHS. Cross-tolerance was achieved for both strains, namely to high salinity, cadmium chloride, and hydrogen peroxide. Scale-up tests resulted in increased tolerance to hydrogen peroxide only for MRS10. During the exposure to this substance, heat-shocked MRS10 rotifers showed an up-regulation of genes related to oxidative stress response and histone modifications, increased production of HSP70, and higher levels of total acetylation of histone H3. A single NLHS proved to induce epigenetic effects when rotifers were exposed to other stressor later in life. However, further studies should elucidate if the NLHS conditions used in this study can yield a persistent outcome, allowing the establishment of tolerant rotifer strain lines and, consequently, a more stable production.