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Alejandro Lucía, María Morán, He Zihong and Jonatan R. Ruiz

Recent research has analyzed the genetic factors that influence world-class athletic status. Much of what we know comes from association studies, with the ACE I/D and ACTN3 R577X polymorphisms having been extensively studied. The association between the ACTN3 R577X variation and elite athlete status in power sports is strongly documented, yet whether the current body of knowledge on other variants can be extrapolated to athletic champion status remains to be determined. Athletic champion status is a complex polygenic trait in which numerous candidate genes, complex gene–gene interactions, and environment–gene interactions are involved. Besides the need for more studies and new approaches taking into account the complexity of the problem, we believe that factors beyond genetic endowment are likely to have a stronger influence in the attainment of athletic champion status.

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Jonatan R. Ruiz, Carmen Fiuza-Luces, Nuria Garatachea and Alejandro Lucia

For centuries, the general consensus has been that vigorous, competitive exercise was harmful and shortened life expectancy. Recent data from prospective cohort studies conducted on marathon runners, professional cyclists, and Olympic athletes indicate, however, that regular intense endurance-exercise training has protective benefits against cardiovascular disease and premature death. There are still important questions to be answered, such as what is the optimal dose, in terms of both duration and intensity of training or competition, beyond which the health benefits of regular exercise stabilize or might even potentially disappear.

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Jorge R. Fernandez-Santos, Jonatan R. Ruiz, Jose Luis Gonzalez-Montesinos and Jose Castro-Piñero

The aim of this study was to analyze the reliability and the validity of the handgrip, basketball throw and pushups tests in children aged 6–12 years. One hundred and eighty healthy children (82 girls) agreed to participate in this study. All the upper body muscular fitness tests were performed twice (7 days apart) whereas the 1 repetition maximum (1RM) bench press test was performed 2 days after the first session of testing. All the tests showed a high reproducibility (ICC > 0.9) except the push-ups test (intertrial difference = 0.77 ± 2.38, p < .001 and the percentage error = 9%). The handgrip test showed the highest association with 1RM bench press test (r = .79, p < .01; R 2 = .621). In conclusion the handgrip and basketball throw tests are shown as reliable and valid tests to assess upper body muscular strength in children. More studies are needed to assess the validity and the reliability of the upper body muscular endurance tests in children.

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Manuel Herrador-Colmenero, Manuel Pérez-García, Jonatan R. Ruiz and Palma Chillón

The first objective was to review and analyze self-reported measures used for assessing mode and frequency of commuting to and from school in youngsters (4–18.5 years old). The secondary objective was to conduct a qualitative appraisal of the identified studies. We searched five online databases: PubMed, SportDiscus, ProQuest, National Transportation Library, and Web of Knowledge. Four categories of search terms were identified: self-report, active transportation, school-aged children and school. Titles and abstracts were reviewed to determine whether the studies met the inclusion criteria. The quality of the reporting of the measures was assessed using a tailored list. The electronic search strategy produced 5,898 studies. After applying the inclusion criteria, we identified 158 studies. Sixty-three studies (39.8%) specified the question about modes of commuting to school. One hundred seven studies (67.7%) directly questioned the study subjects (i.e., children and/or adolescents). Twenty studies (12.7%) posed a valid and reliable question. The quality assessment of the self-report measures was medium. The self-report measures used in the literature for assessing commuting to school tend to be heterogeneous and make difficult interstudies comparisons. Therefore we put forward the idea of a standard question designed to elicit reliable, comparable information on commuting to school.

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José Castro-Piñero, Carmen Padilla-Moledo, Francisco B. Ortega, Diego Moliner-Urdiales, Xiaofen Keating and Jonatan R. Ruiz

Background:

We examined the association of cardiorespiratory fitness and fatness with health complaints and health risk behaviors in 691 (323 girls) Spanish children aged 6 to 17.9.

Methods:

Health complaints and health risk behaviors were self-reported using items of the Health Behavior in School-aged Children questionnaire. Weight and height were measured and body mass index was computed. Cardiorespiratory fitness was measured by the 20-m shuttle-run test, and youth categorized as fit/unfit.

Results:

Unfit youth were more likely to report health complaints sometime (OR: 2.556, 95% CI: 1.299–5.031; and OR: 1.997, 95% CI: 1.162–3.433, respectively) and health risk behaviors such as drinking alcohol sometime (OR: 5.142, 95% CI: 1.214–21.783; and OR: 2.413, 95% CI: 1.484–3.923) than their fit counterparts. Overweight-obese youth were more likely to report health complaints (OR: 1.732, 95% CI: 1.019–2.945; and OR: 1.983, 95% CI: 1.083–3.629, respectively). The analysis of the combined influence of fitness and fatness revealed that fit youth had lower health complaints index than the fat-unfit and unfat-unfit groups (all P < .05).

Conclusions:

Low fitness and overweight-obesity increased the risk of having health complaints in youth, yet high levels of cardiorespiratory fitness might overcome deleterious effects of overweight-obesity on health complaints.

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Francisco J. Amaro-Gahete, Lucas Jurado-Fasoli, Alejandro R. Triviño, Guillermo Sanchez-Delgado, Alejandro De-la-O, Jørn W. Helge and Jonatan R. Ruiz

Purpose: To analyze the diurnal variation of maximal fat oxidation (MFO) and the intensity that elicits MFO (Fatmax) in trained male athletes. Methods: A total of 12 endurance-trained male athletes age 24.7 (4.1) y participated in the study. The authors measured MFO, Fatmax, maximum oxygen uptake (VO2max), and VO2 percentage at ventilatory threshold 2 with a graded exercise protocol performed on 2 days separated by 1 wk. One test was performed in the morning and the other in the afternoon. The authors assessed the participants’ chronotype using the HÖME questionnaire. Results: MFO and Fatmax were greater in the afternoon than in the morning (Δ = 13%, P < .001 and Δ = 6%, P = .001, respectively), whereas there were similar VO2max and ventilatory threshold 2 in the morning, than in the afternoon test (Δ = 0.2%, P = .158 and Δ = 7%, P = .650, respectively). There was a strong positive association between VO2max and MFO in both morning and afternoon assessments (R 2 = .783, P = .001 and R 2 = .663, P < .001, respectively). Similarly, there was a positive association between VO2max and Fatmax in both morning and afternoon assessments (R 2 = .406, P = .024 and R 2 = .414, P = .026, respectively). Conclusion: MFO and Fatmax may partially explain some of the observed diurnal variation in the performance of endurance sports.

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Daniel A. Boullosa, Fábio Y. Nakamura, Jonatan R. Ruiz, Stephen Seiler, Jonathan Esteve-Lanao, Alejandro Lucia, John A. Hawley and David T. Martin

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Palma ChiMón, Francisco B. Ortega, Jonatan R. Ruiz, Ilse De Bourdeaudhuij, David Martínez-Gómez, Germán Vicente-Rodriguez, Kurt Widhalm, Dénes Molnar, Frédéric Gottrand, Marcela González-Gross, Dianne S. Ward, Luis A. Moreno, Manuel J. Castillo and Michael Sjöström

Chillón and Ruiz are with the Department of Physical Education and Sport, University of Granada, Spain. Chillón and Ward are with the Center for Health Promotion and Disease Prevention, University of North Carolina at Chapel Hill, NC, USA. Ortega, Ruiz and Sjöström are with the Unit for Preventive Nutrition, Department of Biosciences and Nutrition, Karolinska Institutet, Sweden. Ortega and Castillo are with the Department of Medical Physiology, University of Granada, Spain. De Bourdeaudhuij is with the Department of Movement and Sport Sciences, Ghent University, Belgium. Martínez-Gómez is with the Immunonutrition Research Group, Department of Metabolism and Nutrition, ICTAN, Spanish National Research Council (CSIC), Spain. Vicente-Rodríguez and Moreno are with Growth, Exercise, Nutrition and Development (GENUD) Research Group, Universidad de Zaragoza, Spain. Widhalm is with the Department of Paediatrics, Division of Clinical Nutrition, Medical University of Vienna, Austria. Molnar is with the Deprtment of Paediatrics, Clinical Center, University of Pécs, Hungary. Gottrand is with Inserm U995, University Lille2 and CIC-9301-CH&U-Inserm, University Hospital of Lille, France. González-Gross is with the Department of Health and Human Performance, Universidad Politécnica de Madrid, Spain.