Facultad de Ciencias de la Salud
Permanent URI for this communityhttps://hdl.handle.net/10637/2790
Search Results
- The effect of combining vibratory platform and unstable footwear on static balance in active young people
2022-03-10 Vibratory platforms (VPs) and unstable footwear (UF) have both shown benefits on balance in some populations. However, there is no evidence about the combined effects of using UF while training on an VP in healthy and physically active young people. We aimed to evaluate the effects of wearing unstable footwear (UF) while training on a whole-body VP on balance in healthy, physically active young people. 23 participants were randomized into groups assigned UF (n = 11) or stable footwear (SF; n = 12). Both groups followed the same training program on an VP with the assigned footwear type twice a week for 12 weeks. The training consisted of performing 8 isometric exercises for progressively longer periods and higher oscillation amplitudes (15–60 s, 1–3 mm), at a fixed vibration frequency (20 Hz). The main outcomes were the antero-posterior and medio-lateral velocities of the center of pressure (COP) recorded using a plantar pressure corridor at baseline, post-treatment and 1-month follow-up. We found a statistically significant difference in the antero-posterior velocity during the monopodal test in the UF group between the different time-points (χ2(2) = 13.282, p = 0.001). Mediolateral COP velocity ranking during the bipodal test was lower for UF than for SF group (U = 19.50, z = − 2.86, p = 0.003) at follow-up. The traditional vibratory platform training does not seem to be effective to improve static balance in physically active young people, however, adding UF provided slightly greater effect.
- Effects of movement representation techniques on motor learning of thumb-opposition tasks
2020-07-23 The present work is the first study that assess long run change after motor learning. The study’s main objective was to evaluate the short to medium-term impact of motor imagery (MI) and action observation (AO) on motor learning of a sequence of thumb-opposition tasks of increasing complexity. We randomly assigned 45 participants to an AO, MI, or placebo observation (PO) group. A sequence of 12 thumb-opposition tasks was taught for 3 consecutive days (4 per day). The primary outcome was accuracy. The secondary outcomes were required time and perfect positioning. The outcomes were assessed immediately after the intervention and at 1 week, 1 month and 4 months postintervention. Regarding the primary outcome, AO group had significantly higher accuracy than the MI or PO group until at least 4 months (p < 0.01, d > 0.80). However, in the bimanual positions, AO was not superior to MI at 1 week postintervention. Regarding secondary outcomes, AO group required less time than the MI group to remember and perform the left-hand and both-hand gestures, with a large effect size (p < 0.01, d > 0.80). In terms of percentage of perfect positions, AO group achieved significantly better results than the MI group until at least 4 months after the intervention in the unimanual gestures (p < 0.01, d > 0.80) and up to 1 month postintervention in the bimanual gestures (p = 0.012, d = 1.29). AO training resulted in greater and longer term motor learning than MI and placebo intervention. If the goal is to learn some motor skills for whatever reason (e.g., following surgery or immobilization.), AO training should be considered clinically.
- Wearable sensors detect differences between the sexes in lower limb electromyographic activity and pelvis 3D kinematics during running
2020-11-12 Each year, 50% of runners su er from injuries. Consequently, more studies are being published about running biomechanics; these studies identify factors that can help prevent injuries. Scientific evidence suggests that recreational runners should use personalized biomechanical training plans, not only to improve their performance, but also to prevent injuries caused by the inability of amateur athletes to tolerate increased loads, and/or because of poor form. This study provides an overview of the di erent normative patterns of lower limb muscle activation and articular ranges of the pelvis during running, at self-selected speeds, in men and women. Methods: 38 healthy runners aged 18 to 49 years were included in this work. We examined eight muscles by applying two wearable superficial electromyography sensors and an inertial sensor for three-dimensional (3D) pelvis kinematics. Results: the largest di erences were obtained for gluteus maximus activation in the first double float phase (p = 0.013) and second stance phase (p = 0.003), as well as in the gluteus medius in the second stance phase (p = 0.028). In both cases, the activation distribution was more homogeneous in men and presented significantly lower values than those obtained for women. In addition, there was a significantly higher percentage of total vastus medialis activation in women throughout the running cycle with the median (25th–75th percentile) for women being 12.50% (9.25–14) and 10% (9–12) for men. Women also had a greater range of pelvis rotation during running at self-selected speeds (p = 0.011). Conclusions: understanding the di erences between men and women, in terms of muscle activation and pelvic kinematic values, could be especially useful to allow health professionals detect athletes who may be at risk of injury.
- Impact attenuation during gait wearing unstable vs traditional shoes
2019-01-13 Introduction: Impact force generates acceleration waves that travel through the body, and possible relationships may be exist between these acceleration waves and injuries. Several studies have analyzed the impact forces on the lower limb in healthy subjects wearing unstable shoes, but there is not accelerometric study analyzing the transmission of these impact forces along the locomotive system. The aim of the present study is to compare the acute effects of wearing unstable shoes (US) vs traditional shoes (TS), on maximum vertical acceleration, impact attenuation, cadence and stride length during gait. Methods: Fourty-three asymptomatic adults participated in the cross-sectional study. Subjects underwent gait analysis with simultaneously collecting heel and tibia peak acceleration, impact magnitude and acceleration rate, as well as shock attenuation and stride parameters (stride length, stride rate). Results: The results showed that wearing US increased cadence (10.99 steps/min; p<0.01), and decreased stride length (0.04 m; p<0.01). Additionally, an increase in maximum tibia peak acceleration, tibia impact magnitude and tibia acceleration rate were reported in the US condition compared to the TS condition, with a decrease of tibia attenuation in the US (p<0.05). Conclusion: Regarding shockwave transmission of ground reaction forces, a lower shock attenuation from the heel to the tibia was reported in the US vs TS condition. Bearing this in mind, it should be pointed that, while it is not yet clear if increased tibia acceleration is harmful to the musculoskeletal system, the US should be used with caution. / Introducción: La fuerza de impacto genera ondas de aceleración que viajan a través del cuerpo, pudiendo existir una relación entre estas ondas y determinados tipos de lesión. Varios estudios han analizado las fuerzas de impacto en el miembro inferior, en sujetos sanos empleando calzado inestable, pero no existen estudios que analicen la transmisión de las aceleraciones a lo largo del aparato locomotor. El objetivo del presente estudio es comparar los efectos agudos del uso de calzado inestable (US) frente al calzado tradicional (TS), sobre la aceleración máxima vertical, la atenuación del impacto, la cadencia y la longitud de la zancada durante la marcha. Método: Cuarenta y tres adultos asintomáticos participaron en el estudio transversal. Los sujetos fueron analizados durante la marcha con la recogida simultánea de la aceleración máxima del talón y la tibia, la magnitud del impacto y la ratio de aceleración, así como la disminución del impacto y determinados parámetros durante la zancada (longitud, frecuencia). Resultados: Los resultados mostraron que el uso de US aumentó la cadencia (10,99 pasos/min; p<0,01) y disminuyó la longitud de la zancada (0,04 m; p<0,01). Adicionalmente, se muestra un aumento en la aceleración máxima, la magnitud del impacto y la ratio de aceleración en la tibia con el calzado US en comparación con la condición de TS, con una disminución en la tibia en los US (p<0.05). Conclusión: La disminución del impacto desde el talón hasta la tibia en la condición de US frente a TS fue menor. Teniendo esto en cuenta, debe señalarse que aunque no está claro si el aumento de la aceleración de la tibia es perjudicial para el sistema musculoesquelético, los US deberían ser empleados con precaución.