Celso Sánchez-Ramírez

Dr. Celso Sánchez-Ramírez

Universidad de Santiago de Chile
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
JWJan Wilke
Jan Wilke
LMLisa Mohr
Lisa Mohr
Adam S. TenfordeAdam S. Tenforde
Adam S. Tenforde
Pascal EdouardPascal Edouard
Pascal Edouard
CFChiara Fossati
Chiara Fossati
KHKarsten Hollander
Karsten Hollander
Governments have restricted public life during the COVID-19 pandemic, inter alia closing sports facilities and gyms. As regular exercise is essential for health, this study examined the effect of pandemic-related confinements on physical activity (PA) levels. A multinational survey was performed in 14 countries. Times spent in moderate-to-vigorous physical activity (MVPA) as well as in vigorous physical activity only (VPA) were assessed using the Nordic Physical Activity Questionnaire (short form). Data were obtained for leisure and occupational PA pre- and during restrictions. Compliance with PA guidelines was calculated based on the recommendations of the World Health Organization (WHO). In total, n = 13,503 respondents (39 ± 15 years, 59% females) were surveyed. Compared to pre-restrictions, overall self-reported PA declined by 41% (MVPA) and 42.2% (VPA). Reductions were higher for occupational vs. leisure time, young and old vs. middle-aged persons, previously more active vs. less active individuals, but similar between men and women. Compared to pre-pandemic, compliance with WHO guidelines decreased from 80.9% (95% CI: 80.3–81.7) to 62.5% (95% CI: 61.6–63.3). Results suggest PA levels have substantially decreased globally during the COVID-19 pandemic. Key stakeholders should consider strategies to mitigate loss in PA in order to preserve health during the pandemic.

JWJan Wilke
Jan Wilke
LMLisa Mohr
Lisa Mohr
Adam S. TenfordeAdam S. Tenforde
Adam S. Tenforde
Pascal EdouardPascal Edouard
Pascal Edouard
CFChiara Fossati
Chiara Fossati
GYGustavo Yuki
Gustavo Yuki
Confinement measures during the COVID-19 pandemic have caused substantial reductions in global physical activity (PA) levels. In view of the manifold health benefits of PA, the development of interventions counteracting this trend is paramount. Our survey with 15,261 participants (38 ± 15 years, 58.5% females) examined preferences towards digital home exercise programs in 14 countries affected by COVID-19. More than two-thirds of the sample (68.4%, n = 10,433) indicated being interested in home exercise, and most participants were willing to work out at least three times per week (89.3%, n = 9328). Binary logistic regression revealed that female sex, working part-time, younger age, and being registered in a gym were associated with willingness to exercise. Flexibility (71.1%, n = 7377), resistance (68.6%, n = 7116), and endurance training (62.4%, n = 6478) were the most preferred types of exercise. Our results may guide health providers in developing individually tailored PA interventions during the current and future pandemics.

1 December 2017 in International Journal of Morphology
Verified
Journal Article
Open access
Celso Sánchez-RamírezCelso Sánchez-Ramírez
Celso Sánchez-Ramírez
EAEduardo Alarcón
Eduardo Alarcón
HMHugo Morales
Hugo Morales
Se sabe que hay gran variabilidad en la morfología de las zonas del pie entre sujetos. Esto es más evidente en deportistas, ya que la práctica de deportes somete a los pies a presiones y deformaciones anatómicas mayores que las que se ejercen en actividades de la vida diaria. Por lo anterior, se desprende que el conocimiento de la morfología del pie de la población objetivo es de alto interés para la confección de calzado apropiado a su forma y dimensiones. El objetivo de esta investigación es caracterizar variables morfológicas referidas a las dimensiones del pie de deportistas seleccionados universitarios chilenos. La muestra se conformó de 169 sujetos de ambos sexos de una población de deportistas universitarios de 23,27 años, 71 kilogramos, 1,71 metros de estatura e índice de masa corporal de 24,29. En las mediciones se utilizó un antropómetro y la clasificación del Arco Plantar Longitudinal Medial (APLM) se realizó mediante el Arch Index. Se demostró que la longitud del pie en hombres y mujeres se corresponde con el 15 % de la estatura del sujeto. La variable Ancho Antepie Normalizado (AAN) equivale al 39 % de la Longitud del Pie (LP), no registrándose diferencias entre sexos. El Ancho del Retropié por su parte, fue correspondiente con el 25 % de LP. El Ancho de Retropie (AR) equivale al 63 % del Ancho Antepie (AA). En cuanto al APLM, las mujeres presentan valores de normalidad ubicados entre 0,13 y 0,24 para pie izquierdo y 0,17 y 0,24 para pie derecho. Se aprecia que la prevalencia de pies planos fue mayor en hombres (25 % a 28 %) que en mujeres (4 % a 6 %) y la prevalencia de pies cavos fue mayor en mujeres (47 % a 53 %) respecto a hombres (27 % a 31 %).

1 March 2023 in Footwear Science
Verified
Journal Article
Closed access
Celso Sánchez-RamírezCelso Sánchez-Ramírez
Celso Sánchez-Ramírez
CRCodi Ramsey
Codi Ramsey
VPValentina Palma-Oyarce
Valentina Palma-Oyarce
EHEduardo Herrera-Hernández
Eduardo Herrera-Hernández
Esteban Aedo-MuñozEsteban Aedo-Muñoz
Esteban Aedo-Muñoz
Heel-to-toe drop (HTD) values may modify the running biomechanics. However, more than twenty additional footwear characteristics may contribute to this too. The aim of this review was to identify and systematise the specific effects caused by different HTDs on running biomechanics. A systematic search was carried out in seven online databases and Footwear Science according to PRISMA protocol for studies that included the practice of endurance running in running shoes with different HTD types. A modified Downs and Black checklist was used to assess the risk of bias. Characteristics of the studies and footwear, the equipment used, and biomechanical outcomes were extracted for qualitative synthesis. Twelve studies were included. Only one had a randomised control trial design, which was classified as ‘good’ (score = 24) quality. The studies reported thirty-nine kinematic and sixteen kinetic variables. HTD ranged between −8 to 16 mm. HTDs did not produce modifications in contact and flight time, stride frequency, and stride length. Some controversial evidence supports that the foot strike pattern changes towards forefoot strike only with HTD 0 compared to HTD 8–10. All evidence indicates that HTD values modified neither ankle, knee, or hip kinematics. Greater evidence supports that the modification of HTD in running shoes does not modify the values of GRF. Despite the controversial nature of the data, the trend is that a lower HTD shows a higher vertical loading rate. The different HTDs modified neither of the joint moments. The negative HTD could be an interesting variable to consider for future research. In addition, it is necessary to study the relationship between the HTD values and different combinations of heel height and forefoot height.

1 June 2020 in International Journal of Morphology
Verified
Journal Article
Open access
PDF file
Celso Sánchez-RamírezCelso Sánchez-Ramírez
Celso Sánchez-Ramírez
XAXavier Aguado
Xavier Aguado
IHIgnacio Hormazábal-Aguayo
Ignacio Hormazábal-Aguayo
EAEduardo Alarcón
Eduardo Alarcón
The objective of this research is to relate the performance in three vertical jump events with morphological variables of the foot and stature. A total of 177 practitioners of 12 sporting events aged 24.5 ±8.0 years, with 71.01 ±13.00 kg of body mass, 1.71±0.09 m height, and BMI of 24.29±3.24 kg·m-2 were evaluated with an anthropometer in terms of foot length (FL), forefoot width (FW), navicular height (NH), and hindfoot width (HW). These variables were normalized to the height of the subjects. From the footprint record the arch index (AI) was obtained, which indicates the morphology of the medial longitudinal foot arch (MLFA). Performance was evaluated in three vertical jump events: countermovement jump (CMJ), squat jump (SJ), and drop jump (DJ), recording the height reached. FL, FW and HW show a weak positive correlation (r<0.4; p<0.05) with the heights achieved in the three types of jump. The stature is strongly associated with FL, FW and HW (r=0.8; r=0.7 and r=0.6; respectively; p<0.05) and with the height in CMJ, SJ, and DJ (r=0.37; r=0.41 and r=0.32, respectively, p<0.05). The only normalized morphological foot variable that maintained consistency in the correlations analysis was the normalized foot length (NFL) with CMJ (r = 0.2, p<0,05). The subjects whose left foot length was equivalent to 14 % of the stature jumped 27.94 ±6.63 cm, those with 15 % jumped 30.96 ±7.4 cm, and those with 16 % jumped 31.03 ±7.8 cm. FL, FW, HW, and stature are moderately correlated with performance in vertical jump events. However, after discarding the stature of the subjects, only the foot length maintained its relation with performance in CMJ.

12 June 2025 in Biomechanics
Verified
Journal Article
Open access
PDF file
FRFelipe Ignacio Inostroza Ríos
Felipe Ignacio Inostroza Ríos
PMPablo Merino
Pablo Merino
Celso Sánchez-RamírezCelso Sánchez-Ramírez
Celso Sánchez-Ramírez
AGAlejandro Bustamante Garrido
Alejandro Bustamante Garrido
JPJorge Pérez-Contreras
Jorge Pérez-Contreras
CBCiro Jose Brito
Ciro Jose Brito
The running cycle is distinguished from the gait cycle by the presence of a flight phase and distinct biomechanical characteristics. Despite existing frameworks for the temporal segmentation of running, these models remain underutilized in comprehensive biomechanical analyses, particularly for delineating phases, subphases, and key events. This study aims to provide a review of historical and contemporary temporal models of the running cycle and to introduce a unified structure designed to enhance analytical precision. The proposed framework divides the running cycle into two primary phases: (a) contact (subdivided into braking and propulsion subphases) and (b) flight, together with three critical events: (1) initial contact, (2) transition of braking–propulsion, (3) toe-off. While leg swing is not considered a phase in this framework due to temporal overlap with other phases, its recognized importance in running mechanics warrants its integrated analysis under the proposed temporal phase delineation. Additionally, methodologies for identifying these events through dynamometry and motion capture are evaluated, emphasizing their role in contextualizing kinetic and kinematic data. By integrating this temporal structure, the study aims to standardize biomechanical assessments of running technique, fostering more consistent comparisons across studies. Such integration has the potential to not only refine interpretations of running mechanics but also to enable practical advancements in athletic training, injury mitigation, and performance optimization.