Open Access
Effects of time-restricted eating and resistance training on skeletal muscle tissue quantity, quality and function in postmenopausal women with overweight or obesity: a study protocol
(Elsevier, 2024-12-30) Alfaro-Magallanes, Víctor Manuel; Medrano Echeverría, María; Echarte Medina, Jon; Osés Recalde, Maddi; Izquierdo Rodríguez, Claudia; Concepción Álvarez, Mara de la Caridad; Galbete Jiménez, Arkaitz; Idoate, Fernando; Zugasti Murillo, Ana; Petrina Jáuregui, María Estrella; Goñi Gironés, María Elena; Ribelles, María Jesús; Amasene, María; Arenaza Etxeberría, Lide; Tejada Garrido, Clara Isabel; Elejalde, E.; Azcárate Jiménez, Unai Xabier; Ruiz Sarrias, Oskitz; Sayar-Beristain, Onintza; García-Ramos, Amador; Martínez Labari, Cristina; Armendáriz Brugos, Cristina; Villanueva Larre, Arantxa; Ruiz, Jonatan R.; Cabeza Laguna, Rafael; Labayen Goñi, Idoia; Ciencias de la Salud; Osasun Zientziak; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
Background & aims: time-restricted eating (TRE) shows promise for weight loss and improving menopauserelated body composition and cardiometabolic health, but its effects on skeletal muscle tissue (SMT) in postmenopausal women are unknown. This study investigates the effects of three weight loss interventions over 12 weeks on SMT quantity, quality, function, and cardiometabolic health in postmenopausal women with overweight/obesity, with effects persistence evaluated at a 12-month follow-up. Methods and results: in this randomized controlled trial, 78 postmenopausal women (50–65 years; BMI 25–40 kg/m2; sedentary lifestyle; eating window ≥12 h/day; no severe metabolic impairments) will be recruited. Participants will be randomly assigned to one of three groups for 12 weeks: TRE, TRE + resistance training, or CR + resistance training. The TRE groups will reduce their eating window to 8 h and receive nutritional advice to adhere to a Mediterranean diet. The CR group will follow a personalized hypocaloric diet (− 500 kcal/day). Resistance training groups will perform supervised resistance training 3 times/week. Primary Outcome: Change in SMT quantity measured by MRI at baseline and after 12 weeks. Secondary Outcomes: intermuscular adipose tissue (IMAT), strength, power, body weight and composition, and cardiometabolic risk factors. Conclusion: this study will illustrate the effects of TRE and TRE combined with resistance exercise compared with the currently recommended obesity-lifestyle treatment on SMT quantity, quality, function, and cardiometabolic markers. The results will offer insights into dietary strategies to combat obesity and metabolic diseases without increasing sarcopenia risk in postmenopausal women, a sparsely studied and particularly affected population.
Open Access
Low cost gaze estimation: knowledge-based solutions
(IEEE, 2020) Martinikorena Aranburu, Ion; Larumbe Bergera, Andoni; Ariz Galilea, Mikel; Porta Cuéllar, Sonia; Cabeza Laguna, Rafael; Villanueva Larre, Arantxa; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Eye tracking technology in low resolution scenarios is not a completely solved issue to date. The possibility of using eye tracking in a mobile gadget is a challenging objective that would permit to spread this technology to non-explored fields. In this paper, a knowledge based approach is presented to solve gaze estimation in low resolution settings. The understanding of the high resolution paradigm permits to propose alternative models to solve gaze estimation. In this manner, three models are presented: a geometrical model, an interpolation model and a compound model, as solutions for gaze estimation for remote low resolution systems. Since this work considers head position essential to improve gaze accuracy, a method for head pose estimation is also proposed. The methods are validated in an optimal framework, I2Head database, which combines head and gaze data. The experimental validation of the models demonstrates their sensitivity to image processing inaccuracies, critical in the case of the geometrical model. Static and extreme movement scenarios are analyzed showing the higher robustness of compound and geometrical models in the presence of user’s displacement. Accuracy values of about 3◦ have been obtained, increasing to values close to 5◦ in extreme displacement settings, results fully comparable with the state-of-the-art.
Open Access
Accurate pupil center detection in off-the-shelf eye tracking systems using convolutional neural networks
(MDPI, 2021) Larumbe Bergera, Andoni; Garde Lecumberri, Gonzalo; Porta Cuéllar, Sonia; Cabeza Laguna, Rafael; Villanueva Larre, Arantxa; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Remote eye tracking technology has suffered an increasing growth in recent years due to its applicability in many research areas. In this paper, a video-oculography method based on convolutional neural networks (CNNs) for pupil center detection over webcam images is proposed. As the first contribution of this work and in order to train the model, a pupil center manual labeling procedure of a facial landmark dataset has been performed. The model has been tested over both real and synthetic databases and outperforms state-of-the-art methods, achieving pupil center estimation errors below the size of a constricted pupil in more than 95% of the images, while reducing computing time by a 8 factor. Results show the importance of use high quality training data and well-known architectures to achieve an outstanding performance.
Open Access
Models for gaze tracking systems
(Hindawi Publishing Corporation, 2007) Villanueva Larre, Arantxa; Cabeza Laguna, Rafael; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
One of the most confusing aspects that one meets when introducing oneself into gaze tracking technology is the wide variety, in terms of hardware equipment, of available systems that provide solutions to the same matter, that is, determining the point the subject is looking at. The calibration process permits generally adjusting nonintrusive trackers based on quite different hardware and image features to the subject. The negative aspect of this simple procedure is that it permits the system to work properly but at the expense of a lack of control over the intrinsic behavior of the tracker. The objective of the presented article is to overcome this obstacle to explore more deeply the elements of a video-oculographic system, that is, eye, camera, lighting, and so forth, from a purely mathematical and geometrical point of view. The main contribution is to find out the minimum number of hardware elements and image features that are needed to determine the point the subject is looking at. A model has been constructed based on pupil contour and multiple lighting, and successfully tested with real subjects. On the other hand, theoretical aspects of video-oculographic systems have been thoroughly reviewed in order to build a theoretical basis for further studies.
Open Access
Fisiopatología y técnicas de registro de los movimientos oculares
(Gobierno de Navarra, 2009) Gila Useros, Luis; Villanueva Larre, Arantxa; Cabeza Laguna, Rafael; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
En el control de la motilidad ocular intervienen varios sistemas funcionales. Los reflejos vestíbulo-oculares y optocinéticos son respuestas automáticas para compensar los movimientos de la cabeza y del entorno visual y poder estabilizar la imagen retiniana sobre un determinado punto de fijación. Los movimientos sacádicos son rápidos desplazamientos de la fijación de un punto a otro del campo visual. Los movimientos de persecución lenta consisten en el seguimiento de estímulos móviles con la mirada. Finalmente, existen movimientos involuntarios de muy escasa amplitud que se producen durante el mantenimiento de la fijación. Cada modalidad funcional de movimiento depende de circuitos neuronales específicos que trabajan coordinadamente para codificar la contracción de los músculos oculomotores correspondiente a la posición adecuada en cada momento. Estos sistemas neuronales pueden verse alterados por múltiples procesos neurológicos de diferente naturaleza y localización dando lugar a una variada gama de trastornos oculomotores. Se revisan los aspectos más destacados de la fisiopatología y de los sistemas de registro de los movimientos oculares.
Open Access
Effects of exercise on bone marrow adipose tissue in children with overweight/obesity: role of liver fat
(Oxford University Press, 2024-08-07) Labayen Goñi, Idoia; Cadenas-Sánchez, Cristina; Idoate, Fernando; Gracia-Marco, Luis; Medrano Echeverría, María; Alfaro-Magallanes, Víctor Manuel; Alcántara Alcántara, Juan Manuel; Rodríguez Vigil, Beatriz; Osés Recalde, Maddi; Ortega, Francisco B.; Ruiz, Jonatan R.; Cabeza Laguna, Rafael; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura; Ciencias de la Salud; Osasun Zientziak; Institute of Smart Cities - ISC; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Gobierno de Navarra / Nafarroako Gobernua
Context: Exercise reduces adiposity, but its influence on bone marrow fat fraction (BMFF) is unknown; nor is it known whether a reduction in liver fat content mediates this reduction. Objectives: This work aimed to determine whether incorporating exercise into a lifestyle program reduces the lumbar spine (LS) BMFF and to investigate whether changes in liver fat mediate any such effect.Methods Ancillary analysis of a 2-arm, parallel, nonrandomized clinical trial was conducted at primary care centers in Vitoria-Gasteiz, Spain. A total of 116 children with overweight/obesity were assigned to a 22-week family-based lifestyle program (control group [n = 57]) or the same program plus an exercise intervention (exercise group [n = 59]). The compared interventions consisted of a family-based lifestyle program (two 90-minute sessions/month) and the same program plus supervised exercise (three 90-minute sessions/week). The primary outcome examined was the change in LS-BMFF between baseline and 22 weeks, as estimated by magnetic resonance imaging. The effect of changes in hepatic fat on LS-BMFF were also recorded.Results Mean weight loss difference between groups was 1.4 +/- 0.5 kg in favor of the exercise group. Only the children in the exercise group experienced a reduction in LS-BMFF (effect size [Cohen d] -0.42; CI, -0.86 to -0.01). Importantly, 40.9% of the reductions in LS-BMFF were mediated by changes in percentage hepatic fat (indirect effect: beta=-0.104; 95% CI, -0.213 to -0.019). The effect of changes in hepatic fat on LS-BMFF was independent of weight loss.Conclusion The addition of exercise to a family-based lifestyle program designed to reduce cardiometabolic risk improves bone health by reducing LS-BMFF in children with overweight or obesity. This beneficial effect on bone marrow appears to be mediated by reductions in liver fat.
Open Access
Synthetic gaze data augmentation for improved user calibration
(Springer, 2021) Garde Lecumberri, Gonzalo; Larumbe Bergera, Andoni; Porta Cuéllar, Sonia; Cabeza Laguna, Rafael; Villanueva Larre, Arantxa; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
In this paper, we focus on the calibration possibilitiesó of a deep learning based gaze estimation process applying transfer learning, comparing its performance when using a general dataset versus when using a gaze specific dataset in the pretrained model. Subject calibration has demonstrated to improve gaze accuracy in high performance eye trackers. Hence, we wonder about the potential of a deep learning gaze estimation model for subject calibration employing fine-tuning procedures. A pretrained Resnet-18 network, which has great performance in many computer vision tasks, is fine-tuned using user’s specific data in a few shot adaptive gaze estimation approach. We study the impact of pretraining a model with a synthetic dataset, U2Eyes, before addressing the gaze estimation calibration in a real dataset, I2Head. The results of the work show that the success of the individual calibration largely depends on the balance between fine-tuning and the standard supervised learning procedures and that using a gaze specific dataset to pretrain the model improves the accuracy when few images are available for calibration. This paper shows that calibration is feasible in low resolution scenarios providing outstanding accuracies below 1.5 ∘ ∘ of error.
Open Access
Differences in specific abdominal fat depots between metabolically healthy and unhealthy children with overweight/obesity: the role of cardiorespiratory fitness
(Wiley, 2023) Cadenas-Sánchez, Cristina; Medrano Echeverría, María; Villanueva Larre, Arantxa; Cabeza Laguna, Rafael; Idoate, Fernando; Osés Recalde, Maddi; Rodríguez Vigil, Beatriz; Álvarez de Eulate, Natalia; Alberdi Aldasoro, Nerea; Ortega, Francisco B.; Labayen Goñi, Idoia; Ciencias de la Salud; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Institute of Smart Cities - ISC; Osasun Zientziak; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Objectives: Fat depots localization has a critical role in the metabolic health status of adults. Nevertheless, whether that is also the case in children remains under- studied. Therefore, the aims of this study were: (i) to examine the differ-ences between metabolically healthy (MHO) and unhealthy (MUO) overweight/obesity phenotypes on specific abdominal fat depots, and (ii) to further explore whether cardiorespiratory fitness plays a major role in the differences between metabolic phenotypes among children with overweight/obesity. Methods: A total of 114 children with overweight/obesity (10.6 ±1.1 years, 62 girls) were included. Children were classified as MHO (n=68) or MUO. visceral (VAT), abdominal subcutaneous (ASAT), intermuscular abdominal (IMAAT), psoas, hepatic, pancreatic, and lumbar bone marrow adipose tissues were measured by magnetic resonance imaging. Cardiorespiratory fitness was assessed using the 20 m shuttle run test. Results: MHO children had lower VAT and ASAT contents and psoas fat fraction compared to MUO children (difference =12.4%– 25.8%, all p<0.035). MUO- unfit had more VAT and ASAT content than those MUO- fit and MHO- fit (difference =34.8%– 45.3%, all p<0.044). MUO- unfit shows also greater IMAAT fat fraction than those MUO- fit and MHO- fit peers (difference =16.4%– 13.9% respectively, all p≤0.001). In addition, MHO- unfit presented higher IMAAT fat fraction than MHO- fit (difference =13.4%, p<0.001). MUO- unfit presented higher psoas fat fraction than MHO- fit (difference =29.1%, p=0.008). Conclusions: VAT together with ASAT and psoas fat fraction, were lower in MHO than in MUO children. Further, we also observed that being fit, regardless of metabolic phenotype, has a protective role over the specific abdominal fat depots among children with overweight/obesity.
Open Access
SeTA: semiautomatic tool for annotation of eye tracking images
(ACM, 2019) Larumbe Bergera, Andoni; Porta Cuéllar, Sonia; Cabeza Laguna, Rafael; Villanueva Larre, Arantxa; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Availability of large scale tagged datasets is a must in the field of deep learning applied to the eye tracking challenge. In this paper, the potential of Supervised-Descent-Method (SDM) as a semiautomatic labelling tool for eye tracking images is shown. The objective of the paper is to evidence how the human effort needed for manually labelling large eye tracking datasets can be radically reduced by the use of cascaded regressors. Different applications are provided in the fields of high and low resolution systems. An iris/pupil center labelling is shown as example for low resolution images while a pupil contour points detection is demonstrated in high resolution. In both cases manual annotation requirements are drastically reduced.
Open Access
Gaze tracking system model based on physical parameters
(World Scientific Publishing, 2007) Villanueva Larre, Arantxa; Cabeza Laguna, Rafael; Porta Cuéllar, Sonia; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
In the past years, research in eye tracking development and applications has attracted much attention and the possibility of interacting with a computer employing just gaze information is becoming more and more feasible. Efforts in eye tracking cover a broad spectrum of fields, system mathematical modeling being an important aspect in this research. Expressions relating to several elements and variables of the gaze tracker would lead to establish geometric relations and to find out symmetrical behaviors of the human eye when looking at a screen. To this end a deep knowledge of projective geometry as well as eye physiology and kinematics are basic. This paper presents a model for a bright-pupil technique tracker fully based on realistic parameters describing the system elements. The system so modeled is superior to that obtained with generic expressions based on linear or quadratic expressions. Moreover, model symmetry knowledge leads to more effective and simpler calibration strategies, resulting in just two calibration points needed to fit the optical axis and only three points to adjust the visual axis. Reducing considerably the time spent by other systems employing more calibration points renders a more attractive model.