Lluís Capdevila

Effects of a post-weaning cafeteria diet in young rats: metabolic syndrome, reduced activity and low anxiety-like behaviour.

Among adolescents, overweight, obesity and metabolic syndrome are rapidly increasing in recent years as a consequence of unhealthy palatable diets. Animal models of diet-induced obesity have been developed, but little is known about the behavioural patterns produced by the consumption of such diets. The aim of the present study was to determine the behavioural and biochemical effects of a cafeteria diet fed to juvenile male and female rats, as well as to evaluate the possible recovery from these effects by administering standard feeding during the last week of the study. Two groups of male and female rats were fed with either a standard chow diet (ST) or a cafeteria (CAF) diet from weaning and for 8 weeks. A third group of males (CAF withdrawal) was fed with the CAF diet for 7 weeks and the ST in the 8th week. Both males and females developed metabolic syndrome as a consequence of the CAF feeding, showing overweight, higher adiposity and liver weight, increased plasma levels of glucose, insulin and triglycerides, as well as insulin resistance, in comparison with their respective controls. The CAF diet reduced motor activity in all behavioural tests, enhanced exploration, reduced anxiety-like behaviour and increased social interaction; this last effect was more pronounced in females than in males. When compared to animals only fed with a CAF diet, CAF withdrawal increased anxiety in the open field, slightly decreased body weight, and completely recovered the liver weight, insulin sensitivity and the standard levels of glucose, insulin and triglycerides in plasma. In conclusion, a CAF diet fed to young animals for 8 weeks induced obesity and metabolic syndrome, and produced robust behavioural changes in young adult rats, whereas CAF withdrawal in the last week modestly increased anxiety, reversed the metabolic alterations and partially reduced overweight.

Comparison of omega wave system and polar S810i to detect R-R intervals at rest

The present study was performed to compare R-R interval data and heart rate variability indices obtained from the Polar S810i and the Omega Wave Sport System for a total of 96 adults in a supine position. Data were simultaneously recorded with the Polar S810i and the Omega Wave Sport System and processed by unique software. Bland-Altman analysis for the R-R intervals shows minimal bias for free and paced breathing. No significant differences were observed for heart rate variability indices derived from the signal from both devices, except for the power of the high frequency band and the acceleration changes index during either free or paced breathing. Coefficients of correlations were all above 0.96. These data suggest that both systems are valid to record R-R interval signals and to obtain a valid analysis of heart rate variability. However, Omega Wave Sport System enables data to be collected without any artifacts making the analysis of heart rate variability easier than the analysis of Polar S810i. Nevertheless, Polar S810i continues to be more practical in clinical and applied situations due to the affordability of the device.

Facial Video-Based Photoplethysmography to Detect HRV at Rest.

Our aim is to demonstrate the usefulness of photoplethysmography (PPG) for analyzing heart rate variability (HRV) using a standard 5-min test at rest with paced breathing, comparing the results with real RR intervals and testing supine and sitting positions. Simultaneous recordings of R-R intervals were conducted with a Polar system and a non-contact PPG, based on facial video recording on 20 individuals. Data analysis and editing were performed with individually designated software for each instrument. Agreement on HRV parameters was assessed with concordance correlations, effect size from ANOVA and Bland and Altman plots. For supine position, differences between video and Polar systems showed a small effect size in most HRV parameters. For sitting position, these differences showed a moderate effect size in most HRV parameters. A new procedure, based on the pixels that contained more heart beat information, is proposed for improving the signal-to-noise ratio in the PPG video signal. Results were acceptable in both positions but better in the supine position. Our approach could be relevant for applications that require monitoring of stress or cardio-respiratory health, such as effort/recuperation states in sports.

Return to Play After Soleus Muscle Injuries.

Background Soleus muscle injuries are common in different sports disciplines. The time required for recovery is often difficult to predict, and reinjury is common. The length of recovery time might be influenced by different variables, such as the involved part of the muscle. Hypothesis Injuries in the central aponeurosis have a worse prognosis than injuries of the lateral or medial aponeurosis as well as myofascial injuries. Study Design Case series; Level of evidence, 4. Methods A total of 61 high-level or professional athletes from several sports disciplines (soccer, tennis, track and field, basketball, triathlon, and field hockey) were reviewed prospectively to determine the recovery time for soleus muscle injuries. Clinical and magnetic resonance imaging evaluation was performed on 44 soleus muscle injuries. The association between the different characteristics of the 5 typical muscle sites, including the anterior and posterior myofascial and the lateral, central, and medial aponeurosis disruption, as well as the injury recovery time, were determined. Recovery time was correlated with age, sport, extent of edema, volume, cross-sectional area, and retraction extension or gap. Results Of the 44 patients with muscle injuries who were analyzed, there were 32 (72.7%) strains affecting the myotendinous junction (MT) and 12 (23.7%) strains of the myofascial junction. There were 13 injuries involving the myotendinous medial (MTM), 7 affecting the MT central (MTC), 12 the MT lateral (MTL), 8 the myofascial anterior (MFA), and 4 the myofascial posterior (MFP). The median recovery time (±SD) for all injuries was 29.1 ± 18.8 days. There were no statistically significant differences between the myotendinous and myofascial injuries regarding recovery time. The site with the worst prognosis was the MTC aponeurosis, with a mean recovery time of 44.3 ± 23.0 days. The site with the best prognosis was the MTL, with a mean recovery time of 19.2 ± 13.5 days (P < .05). There was a statistically significant correlation between recovery time and age (P < .001) and between recovery time and the extent of retraction (P < .05). Conclusion Wide variation exists among the different types of soleus injuries and the corresponding recovery time for return to the same level of competitive sports. Injuries in the central aponeurosis have a significantly longer recovery time than do injuries in the lateral and medial aponeurosis and myofascial sites.

Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats

Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders.

An application of fractional differintegration to heart rate variability time series

Fractional differintegration is used as a new tool to characterize heart rate variability time series. This paper proposes and focuses in two indexes (αc and fnQ) derived from the fractional differintegration operator. Both indexes are applied to fractional Gaussian noise (fGn) and actual RR time series in order to test their behavior. In the analysis of monofractal time series, αc is linearly related with the Hurst exponent and the estimation of the exponent by the proposed index has lower variance than by using Detrended Fluctuation Analysis (DFA) or the periodogram. The other index fnQ quantifies how the time series adjust to a monofractal time series. Age, postural changes and paced breathing cause significant changes on fnQ while αc only shows significant changes due to posture. In the analyzed actual HRV time series, αc shows good correlation with the short term scaling exponent obtained by DFA, LF/HF and RMSSD while no correlations have been found for fnQ.

Calidad de vida en adolescentes supervivientes de cáncer infantojuvenil

BACKGROUND AND OBJECTIVE To assess health-related quality of life of adolescent survivors of childhood cancer, compared to adolescents health-related quality of life who had no history of cancer. PATIENTS AND METHOD A total of 372 adolescents aged between 14 and 19 years, 34 cancer survivors and a comparison group of 338 peers without a history of cancer, were assessed. All of them filled in the SF-12v(2) in a cross-sectional study. RESULTS Survivors revealed significantly higher mean values compared to the normative group for the Mental Component Scale (MCS) from the SF-12v(2) (52,60 vs. 47,85; p=0,004; IC 95%, -7,9--1,6). No significant differences between groups were found for the Physical Component Scale (PCS), even though adolescent survivors of childhood cancer showed higher mean scores (54,03 vs. 52,72). CONCLUSIONS Adolescent cancer survivors showed a satisfactory quality of life (mean scores around the normative values), and, specifically, they reported greater perception of psychological wellbeing compared to peers.

Treadmill Intervention Attenuates the Cafeteria Diet-Induced Impairment of Stress-Coping Strategies in Young Adult Female Rats

The current prevalence of diet-induced overweight and obesity in adolescents and adults is continuously growing. Although the detrimental biochemical and metabolic consequences of obesity are widely studied, its impact on stress-coping behavior and its interaction with specific exercise doses (in terms of intensity, duration and frequency) need further investigation. To this aim, we fed adolescent rats either an obesogenic diet (cafeteria diet, CAF) or standard chow (ST). Each group was subdivided into four subgroups according to the type of treadmill intervention as follows: a sedentary group receiving no manipulation; a control group exposed to a stationary treadmill; a low-intensity treadmill group trained at 12 m/min; and a higher intensity treadmill group trained at 17 m/min. Both the diet and treadmill interventions started at weaning and lasted for 8 weeks. Subjects were tested for anxiety-like behavior in the open field test and for coping strategies in the two-way active avoidance paradigm at week 7 and were sacrificed at week 8 for biometric and metabolic characterization. CAF feeding increased the weight gain, relative retroperitoneal white adipose tissue (RWAT %), and plasma levels of glucose, insulin, triglycerides and leptin and decreased the insulin sensitivity. Treadmill intervention partially reversed the RWAT% and triglyceride alterations; at higher intensity, it decreased the leptin levels of CAF-fed animals. CAF feeding decreased the motor activity and impaired the performance in a two-way active avoidance assessment. Treadmill intervention reduced defecation in the shuttle box, suggesting diminished anxiety. CAF feeding combined with treadmill training at 17 m/min increased the time spent in the center of the open field and more importantly, partially reversed the two-way active avoidance deficit. In conclusion, this study demonstrates that at doses that decreased anxiety-like behavior, treadmill exercise partially improved the coping strategy in terms of active avoidance behavior in the CAF-fed animals. This effect was not observed at lower doses of treadmill training.

Perceived Tiredness and Heart Rate Variability in Relation to Overload during a Field Hockey World Cup

The aim of the study was to examine the utility of perceived tiredness to predict cardiac autonomic response to overload among field hockey players during the 2006 World Cup. The French Society for Sports Medicine (SFMS) questionnaire was administered at the start of the Cup to evaluate perception of tiredness. Autonomic function was assessed nine days later at the semifinal match by time and frequency domain analysis of heart rate variability. An anxiety questionnaire was administered so that the effect of precompetitive anxiety on heart rate variability could be controlled. Results showed a negative correlation between perceived tiredness scores and time domain indexes, and a positive correlation of perceived tiredness scores and the high frequency component ratio (LF/HF ratio) of heart rate variability. Anxiety did not influence the precompetitive cardiac response despite somatic anxietys correlation with sympathetic response (LF/HF ratio) and tiredness scores. Perceived tiredness predicted the autonomic cardiac response to competitive overload. Thus, the perceived tiredness assessment would be a good early marker of fatigue and overload states during competition.

Surviving cancer: The psychosocial outcomes of childhood cancer survivors and its correlates

This study assessed the psychosocial outcomes of adolescent cancer survivors and their relationship with personal and socio-familiar factors. Using a cross-sectional design, 41 survivors answered the four psychosocial dimensions of the KIDSCREEN-52 questionnaire and measures for social support and coping. Similarly, 41 parents answered coping and cancer-related distress measures. All psychosocial scores were within normative values (50 ± 10). Multiple linear regression analyses revealed four models with a range of explained variance between 9.4 percent and 31.9 percent that include the informative and emotional support, parental distress, and coping. This study contributes to the understanding of psychosocial outcomes of childhood cancer survivors and its correlates.