Fitness, strength and muscle mass are diminished in kidney transplant patients, resulting in a poorer quality of life which might entail an increased risk to their health.

We analyzed the levels of fitness, muscle structure and quality of life of adults after kidney transplant and healthy adults.
Patients and methods: A total of 16 kidney transplant patients and 21 healthy controls performed several fitness test, isokinetic evaluation of knee flexion and extension and ultrasonography muscle thickness assessment. They also completed the quality of life questionnaire SF-36.

Physical fitness, muscle structure and quality of life of the kidney transplant recipients were significantly poorer than the controls. The transplant patients performed less well in the “get up and go” and “sit to stand” test (p < .001) as well as in assessments of muscle structure, strength and power. The patients had a poorer score in their quality of life assessments, differing from the controls in domains of physical function, physical role, general health and social function (p < .001).

Firman este artículo, por parte:

Sonsoles Hernández Sánchez a,∗, Juan J. Carrerob, David García López c, Juan Azael Herrero Alonso c,d, Héctor Menéndez Alegre c,d y Jonatan R. Ruiz. a

a Grupo de Investigación PROmoting FITness and Health through physical activity (PROFITH), Departamento de Educación Física y Deportiva, Facultad de Ciencias del Deporte, Universidad de Granada, Granada, España
b Renal Medicine and Baxter Novum, CLINTEC, Karolinska Institutet, Estocolmo, Suecia
c Laboratorio de Fisiología, Facultad de Ciencias de la Salud, Universidad Europea Miguel de Cervantes, Valladolid, España

d Centro de Investigación en Discapacidad Física, Valladolid, España

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Active forms of transport, such as walking and cycling, have been recognized as potential avenues to increase daily physical activity providing an alternative to more traditional physical activity domains such as sport and exercise. Active school transport has been proposed as a way to increase physical activity in children and youth at the population level, with the added benefit of reducing emissions of greenhouse gases and other pollutants.

Despite these benefits, longitudinal studies performed in the last decades have shown a decline in the rates of active transport mainly due to barriers such as the distance from home to school or family decisions. In 2011, a systematic review of 14 intervention studies to promote this behavior concluded that more research should be conducted to further evaluate interventions and to determine the most successful strategies for increasing active transport to school.

Consequently, researchers from the University of Granada in collaboration with the Department of Epidemiology, University of North Carolina (USA), carried out an update of this previous review published in 2011 by Chillon et al, publishing the update review in Preventive Medicine, an international scholarly journal that publishes original articles on the science and practice of disease prevention, health promotion, and public health policymaking.

The researchers concluded that most of the intervention studies (21/23) on walking and bicycling to/from school indicated poor quality of the study components as well as low effect size. In addition, the current systematic review study can aid researchers and practitioners who wish to create future strategies to promote this behavior and understand the effects of intervention programs on children using active transportation to school.

This article is signed by UGR, researchers Emilio Villa-González, Yaira Barranco Ruiz and Palma Chillón (senior author), in addition to Kelly Evenson from the University of North Carolina.

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The addition of physical exercise to an educational lifestyle intervention increased the number of children that improved the percentage of hepatic fat and body composition 

Among the children that participated in the exercise sessions, 54% significantly reduced their percentage of hepatic fat, in comparison with 34% of the children that only participated in the lifestyle program

Exercise and lifestyle interventions reduce fat mass, cardiovascular risk and hepatic fat in children and adolescents. Therefore, they have been recommended as a treatment option for pediatric obesity, a global pandemic that affects more than 40% of the youths in Spain.

However, not all the participants improve all the variables after performing a particular intervention. “Whereas some participants improve in one or several outcomes after an intervention (these are called responders), others do not change or even worsen their response (called non-responders to the intervention). Usually, the published studies only report the results as overall mean values of the intervention group or groups, but they do not provide individual  information of what happens to each one of the participants”- notes María Medrano, author of a recently published article in “Pediatric Diabetes”, which was part of her doctoral thesis.

This study compared the number of responders for hepatic fat, weight, total and abdominal adiposity and the GGT liver enzyme between two different interventions. “Half of all children participated in a 22-week family lifestyle and psycho-educational program, which consisted of a number of sessions and a workshop one day every two weeks. The other half of the children performed three supervised game-based high-intensity exercise sessions per week. “In total, more than 120 families participated in the study”- explains María Medrano, researcher of the IS-FOOD institute group ELIKOS (ELikadura, arIKeta fisikoa eta Osasuna: Nutrición, Actividad Física y Salud) and the person responsible for the exercise sessions. 

After participating in the intervention that included physical exercise, 54% of the children significantly reduced or were responders for hepatic fat, 90% for total adiposity and 69% for the GGT liver enzyme. The number of responders for the non-exercise intervention was significantly lower for all the aforementioned variables (34% for hepatic fat, 60% for total adiposity, ad 39% for the GGT). Moreover, it seems that cardiorespiratory fitness improvements could explain, at least in part, the differences between responders and non-responders for some variables.

The authors of this article, researchers from the Public University of Navarra and the University of Granada, highlight the importance of promoting this kind of intervention as part of childhood obesity treatment and its comorbidities such as hepatic steatosis, which increases the risk of type 2 diabetes, cardiovascular diseases and future liver complications.

What kind of intervention would benefit a higher number of people?

The aim of this research, focused on the number of responders, is to find the kind of intervention in which a higher number of the participants will reach benefits for their health after their participation. 

The article published in the cited Journal of Pediatrics shows that including physical exercise in a childhood obesity treatment program increases the number of children that improve their health after participating in the program. “The results of this work reveal that a higher number of children who are overweight or obese reduced the percentage of hepatic fat, weight, adiposity and GGT liver enzyme after participating in the intervention which included exercise in addition to the educational lifestyle program”- indicates María Medrano.

This article was signed by the researchers Idoia Labayen, Lide Arenaza Etxeberria, Robinson Ramírez-Vélez and the aforementioned cited María Medrano, from the Public University of Navarra, and Jonatan Ruiz Ruiz y Francisco B. Ortega Porcel, from the University of Granada.

It cannot be determined whether the cow’s milk consumption has a positive effect on exercise performance and recovery of muscle function.

The large heterogeneity of cow’s milk intake (amount of cow’s milk and timing of consuming the cow’s milk), the type of intervention (exercise) and the diversity of the observed results preclude determining whether the cow’s milk consumption has an effect on exercise performance and recovery of muscle function.

Although different results were observed across studies, the dairy products consumption, such as the cow’s milk, makes cow’s milk an interesting option for both, professional and amateurs athletes due to it is nutritional properties, relatively low price and high availability at the supermarkets. Of note, some of the included studies found positive results on exercise performance, recovery of muscle function, or both, as can be found on the present systematic review published in the scientific journal “Journal of the International Society of Sports Nutrition”.

The authors of this paper, who work at the University of Granada and the Public University of Navarra, highlight the relevance of dairy products consumption in physical active population, specially cow’s milk consumption, if there is no exists contraindications (allergies and/or intolerances) that may preclude their ingestion.

This paper is signed by the researchers Juan Manuel Alcántara Alcántara, Guillermo Sánchez Delgado, Borja Martínez Téllez & Jonatan Ruiz Ruiz of the University of Granada. With the collaboration of Idoia Labayen, researcher of the Public University of Navarra.

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PMID: 31060583 

PMCID: PMC6503439 

DOI: 10.1186/s12970-019-0288-5

Higher levels of physical activity and cardiorespiratory fitness are associated with higher diversity and gut microbiota composition in healthy adults 

Researchers from the University of Granada (UGR) have carried out a review to summarize the international scientific literature with the aim of knowing whether physical activity and exercise can improve the composition of the intestinal microbiota

Humans live in symbiosis with different microorganisms. The most representative in gut are Firmicutes (60%–65%), Bacteroidetes (20%–25%), and Proteobacteria (5%–10%). Something important is the term Eubiosis, which means that there is an intestinal microbial balance, associated with good health status. However, a microbial imbalance, known as dysbiosis, is present in various pathologies, such as obesity, diabetes and cardiovascular diseases. In animal models the exercise restores eubiosis, thus improving their health. 

The present systematic review included 18 studies: 9 were observational, 4 reported very short-term exercise interventions, and 5 reported medium/long-term exercise interventions, all in healthy adults. Results showed that physical activity and cardiorespiratory fitness seem to be positively associated with diversity and gut microbiota composition, whereas exercise interventions seem to be positively related to gut microbiota composition. However, the heterogeneity of the studies examined must be highlighted.

The authors of this publication, who work at the universities of Granada and Leiden, emphasize the importance of promoting changes on composition gut microbiota through exercise, as part a non-pharmaceutical treatment to improve health. 

This paper is signed by the researchers Lourdes Ortiz Alvarez and Huiwen Xu of the University of Granada. With the collaboration of Borja Martinez Tellez of the Leiden University Medical Center.

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Researchers from the University of Granada are leading a project called PREFIT (FITness assessment in PREschoolers), a multicenter Project in 10 spanish cities, which has proposed physical fitness reference standards in preschoolers. 

Results have been published in Journal of Science and Medicine in Sport, one of the best Journals in the Sports Sciences field. 

Researchers have evaluated physical fitness in more than 3000 spanish preschoolers thanks to the multicenter Project, the PREFIT Project, leaded by the University of Granada together with the collaboration of University of Cádiz, University of Almeria, Universidad de Castilla La-Mancha, Universidad Politécnica de Madrid, University Jaume I, Public University of Navarra, University of Zaragoza, University of the Balearic Islands and University of las Palmas de Gran Canaria.

Physical fitness assessment

Do you know that it is possible to assess aerobic capacity, strength, speed-agility and balance in children from 3 to 5 years? Have you already performed the assessment and you do not know how to interpret them? Researchers from the University of Granada and collaborators, have developed a pioneer worldwide study in Spanish preschoolers (3-5 years), providing reference standards by age and sex groups. Another relevant finding was that the fitness difference in physical fitness already existed in 3 years boys and girls, and it increases as the age increase.

“Physical fitness assessment in children from 3 to 5 years in a challenge, but not for being the youngest are less important. From here arose the need to create a set of tests to assess the physical fitness of preschoolers and the PREFIT project”, says Francisco B. Ortega, professor in the Department of Physical and Sports Education at the Faculty of Sports Sciences, last author of the work, and principal investigator of the PREFIT project. “ 

Cristina Cadenas-Sanchez, postdoctoral researcher, Project manager of the PREFIT project and first author of the work, affirms that “These results are of great help to all professionals related to health, sport and education as it allows them to identify those preschoolers with very low physical fitness and help them improve it to have good health in the future. “

Therefore, researchers at the University of Granada conclude that “the final message we want to spread is that we must be active to be in good physical fitness from 3 years-old”.

Signed this article, in addition to those already mentioned, Jonatan Ruiz Ruiz y Borja Martínez-Téllez (both from the University of Granada), Tim Intemann (University of Bremen), Idoia Labayen (Public University of Navarra), Ana B. Peinado (Universidad Politécnica de Madrid), Josep Vidal-Conti (University of Balears Islands), Joaquín Sanchis-Moysi (Universyt of Las Palmas de Gran Canaria), Diego Moliner-Urdiales (University Jaume I), Manuel A. Rodríguez Pérez (University of Almería), Jorge Cañete García-Prieto (Universidad de Castilla-La Mancha), Jorge del Rosario Fernández-Santos (University of Cádiz), Germán Vicente-Rodríguez (University of Zaragoza), y Marie Löf (Karolinska Institutet). 

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Link to the original article (Science direct)

Muscular strength seems to be related with this thermogenic tissue in humans

Humans have metabolically active brown adipose tissue (BAT). However, what is the relation between exercise or physical activity with this tissue remains controversial. Therefore, the main aim of the present study is to examine whether cardiorespiratory fitness and muscular strength are associated with brown adipose tissue (BAT) volume and activity after exposure to cold in young, sedentary adults. Cardiorespiratory fitness was determined in 119 young, healthy, sedentary adults (68% women) via the maximum treadmill exercise test, and their muscular strength assessed by the handgrip strength test and the 1-repetition maximum bench and leg press tests. Some days later, all subjects were exposed to 2 h of personalized exposure to cold and their cold-induced BAT volume and activity determined by a combination of 18F-fluorodeoxyglucose (18F- FDG) positron emission tomography and computed tomography scan. Cardiorespiratory fitness was associated with neither the BAT volume nor BAT activity. However, handgrip strength with respect to lean body mass was positively (though weakly) associated with BAT activity as represented by the 18F-FDG uptake. The above relationships remained after adjusting for several confounders. No other associations were found. Handgrip strength with respect to lean body mass is positively associated with BAT activity (SUVmean and SUVpeak) in young adults after exposure to cold – but only weakly. Further studies are needed to reveal the relationship between muscular fitness and human BAT characteristics.

This paper is signed by the researchers Borja Martinez-Tellez, Guillermo Sanchez-Delgado, Franciso Amaro-Gahete, Francisco M. Acosta & Jonatan Ruiz of the University of Granada.

Women are able to dissipate higher amounts of heat via the skin in comparison to men

The thermic effect of food (TEF) refers to the increase of the metabolic rate and body temperature in response to a single meal. To date, most of the studies have focused on determiníng the TEF in terms of energy expenditure, but little is known about which is the response in terms of skin temperature. The aim of this study was to analyze whether the thermic effect of food (TEF) on the skin temperature with a standardized and individualized liquid meal test is different in young adult men than in young adult women. A total of 104 young adults (36 men and 68 women, age: 18 to 25 years old) consumed a standardized and individualized liquid meal (energy intake: 50% of measured basal metabolic rate, 50% carbohydrates, 35% fat, 15% protein). The skin temperature was measured by means of 17 iButtons during 3h and 20 min. The mean, proximal, distal, and supraclavicular skin temperature, as well as the peripheral gradient, were determined as a proxy of a peripheral vasoconstriction. The participants reported the thermal sensation of the whole body, clavicular, feet, and hands zones. The body composition was measured by dual X-ray absorptiometry. 

The overall, mean, proximal, and supraclavicular skin temperature significantly increased after the meal intake. There was a postprandial peripheral vasoconstriction right after the meal intake and over the first hour and a peripheral vasodilatation during the second and third hour. Women had a higher increase in all skin temperature parameters in comparison to men, whereas there were no sex differences in the proximal skin temperature. The pattern of thermal sensation was similar between sexes, but women always felt colder than men. All of the results persisted after adjusting the analyses for body composition or menstrual cycle. 

Therefore, a standardized and individualized liquid meal test increases the skin temperature in young adults, being the thermic effect higher in women than in men.

This paper is signed by the researchers Borja Martinez-Tellez, Lourdes Ortiz-Alvarez, Guillermo Sanchez-Delgado, Huiwen Xu, Francisco M. Acosta, Elisa Merchan-Ramirez, Victoria Muñoz-Hernandez, Wendy Martinez-Avila, Miguel Contreras-Gomez, Angel Gil & Jonatan Ruiz of the University of Granada. With the collaboration of Iodia Labayen, researcher of the Public University of Navarra.

A review of the international scientific literature was carried out with the aim of knowing the main barriers that parents perceive to allow their children to travel actively to school, that is, on foot or by bicycle.

In this review, 27 studies were identified and a categorization that defines three types was created: environmental, personal and social. Environmental barriers refer to the human-made environment, such as a building block or a bike path. Personal barriers refer to your own work and school hours or the convenience of taking your children to school. And social barriers include the absence of other children on the way to school or other adults.

The main barriers that parents of Primary Education children perceive for the active transport of their children are references to the built environment and second, the traffic. However, parents of adolescents perceive the built environment, just like parents of children, as well as distance as barriers. Therefore, parents of children and adolescents see the distance, the traffic or the built environment as the main problems.

To improve these perceptions of parents, it is necessary to act with two strategies: a) making environmental changes to offer more safety to parents, making improvements and widening sidewalks, or implementing bike lanes; b) educating parents and their children to reduce these perceived barriers and increase confidence in the environment causing behavioral change by participating in pedibus or “bike train”. It is everyone’s responsibility to ensure that our children are as active as possible for a society with greater health and well-being, as well as for the physical and personal development of our schoolchildren.

This article is signed by the researchers María Jesús Aranda-Balboa, Francisco Javier Huertas-Delgado, Manuel Herrador-Colmenero, Palma Chillón Garzón, from University of Granada. Along with them they have had the researcher Greet Gardon (University of Ghent).

Aranda-Balboa, M. J., Huertas-Delgado, F. J., Herrador-Colmenero, M., Cardon, G., & Chillón, P. (2019). Parental barriers to active transport to school: a systematic review. International journal of public health, 1-12.

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Maximal fat oxidation during exercise is considered a potential marker of metabolic flexibility during exercise.

People with obesity suffer from metabolic inflexibility. However, it seems that those individuals with high levels of cardiorespiratory fitness appear to be relatively protected from this metabolic inflexibility.

Obesity is a major public health problem, and one of the most important risk factors for mortality. Traditionally, obese persons have been thought to suffer from metabolic inflexibility, which is characterized by reduced fat oxidation by the skeletal muscles under fasting conditions and in the post-prandial state. The results obtained by a recent research article published in “The Journal of Clinical Endocrinology and Metabolism” showed that “obese subjects present lower maximal fat oxidation during exercise than their normal-weight counterparts”. 

“However, individuals with obesity who present higher levels of cardiorespiratory fitness also showed greater levels of maximal fat oxidation during exercise. Cardiorespiratory fitness can be therefore considered as a protective cardiometabolic factor in obese subjects”, describes Jonatan R. Ruiz, head of the PROFITH research group, University of Granada.

The authors of this publication, who work at the University of Castilla-La Mancha, in addition to the University of Granada, highlight the importance of promoting exercise interventions to improve both metabolic flexibility and cardiorespiratory fitness levels as a potential treatment of obesity.

This research article is signed by Drs. Francisco J. Amaro-Gahete and Guillermo Sánchez-Delgado, in addition to the aforementioned Dr. Jonatan R. Ruiz. Along with them, Ignacio Ara Rollo of the University of Castilla-La Mancha has also participated in this contribution.

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This study aimed to investigate the effects of different training modalities on Klotho protein plasma levels (S-Klotho) in sedentary middle-aged adults. 

Seventy-four individuals were randomly assigned to 4 different groups: (i) control (no exercise), (ii) physical activity recommendation from the World Health Organization group, (iii) high intensity interval training (HIIT), and (iv) a HIIT + whole-body electromyostimulation.

All exercise training modalities induced an increase in S-Klotho. Moreover, a positive association was observed between changes in lean mass and changes in S-Klotho plasma levels, whereas a negative association was reported between changes in fat mass outcomes and changes in S-Klotho.