MATIAS NOLL

Back Pain Prevalence and Its Associated Factors in Brazilian Athletes from Public High Schools: A Cross-Sectional Study

Most studies on the prevalence of back pain have evaluated it in developed countries (Human Development Index—HDI > 0.808), and their conclusions may not hold for developing countries. The aim of this study was to identify the prevalence of back pain in representative Brazilian athletes from public high schools. This cross-sectional study was performed during the state phase of the 2015 Jogos dos Institutos Federais (JIF), or Federal Institutes Games, in Brazil (HDI = 0.744), and it enrolled 251 athletes, 173 males and 78 females (14–20 years old). The dependent variable was back pain, and the independent variables were demographic, socioeconomic, psychosocial, hereditary, exercise-level, anthropometric, strength, behavioral, and postural factors. The prevalence ratio (PR) was calculated using multivariable analysis according to the Poisson regression model (α = 0.05). The prevalence of back pain in the three months prior to the study was 43.7% (n = 104), and 26% of the athletes reported feeling back pain only once. Multivariable analysis showed that back pain was associated with demographic (sex), psychosocial (loneliness and loss of sleep in the previous year), hereditary (ethnicity, parental back pain), strength (lumbar and hand forces), anthropometric (body mass index), behavioral (sleeping time per night, reading and studying in bed, smoking habits in the previous month), and postural (sitting posture while writing, while on a bench, and while using a computer) variables. Participants who recorded higher levels of lumbar and manual forces reported a lower prevalence of back pain (PR < 0.79), whereas feeling lonely in the previous year, obesity, and ethnicity exhibited the highest prevalence ratio (PR > 1.30). In conclusion, there is no association between exercise levels and back pain but there is an association between back pain and non-exercise related variables.

Monitoring the prevalence of postural changes in schoolchildren

[Purpose] The aim of this study was to identify whether postural changes are prevalent with advancing age using a photogrammetric method performing one-year follow-up study. [Subjects and Methods] Thirty-eight schoolchildren were evaluated in 2011 and 2012 in this cohort study. The subjects underwent a postural evaluation, which involved palpation of reference anatomic points, placement of reflexive markers over the anatomic points, image acquisition, and point digitalization using the Digital Image-based Postural Assessment evaluation software. For data analysis, descriptive statistics and inferential statistics were analyzed by McNemar’s test. [Results] The results showed a significant increase in postural change prevalence for the lumbar spine in the sagittal plane (from 42.2% to 81.6%) and the knees in the frontal plane (from 39.5% to 63.2%) and a significant decrease in the prevalence of scoliosis (from 68.5% to 42.2%). [Conclusion] The findings indicate an increase in the prevalence of postural changes in schoolchildren from Teutônia, RS, Brazil, in 2012 compared with 2011. The development of longitudinal investigations for long-term monitoring of the evolution of posture and of schoolchildren habits’s representing a viable alternative to subsidize health actions.

Evaluation of factors associated with severe and frequent back pain in high school athletes

Several studies have shown that half of all young athletes experience back pain (BP). However, high intensity and frequency of BP may be harmful, and the factors associated with BP severity have not been investigated in detail. Here, we investigated the factors associated with a high intensity and high frequency of BP in high school athletes. We included 251 athletes (173 boys and 78 girls [14–20 years old]) in this cross-sectional study. The dependent variables were a high frequency and high intensity of BP, and the independent variables were demographic, socioeconomic, psychosocial, hereditary, anthropometric, behavioural, and postural factors and the level of exercise. The effect measure is presented as prevalence ratio (PR) with 95% confidence interval (CI). Of 251 athletes, 104 reported BP; thus, only these athletes were included in the present analysis. Results of multivariable analysis showed an association between high BP intensity and time spent using a computer (PR: 1.15, CI: 1.01–1.33), posture while writing (PR: 1.41, CI: 1.27–1.58), and posture while using a computer (PR: 1.39, CI: 1.26–1.54). Multivariable analysis also revealed an association of high BP frequency with studying in bed (PR: 1.19, CI: 1.01–1.40) and the method of carrying a backpack (PR: 1.19, CI: 1.01–1.40). In conclusion, we found that behavioural and postural factors are associated with a high intensity and frequency of BP. To the best of our knowledge, this study is the first to compare different intensities and frequencies of BP, and our results may help physicians and coaches to better understand BP in high school athletes.

Back pain prevalence and associated factors in children and adolescents: an epidemiological population study

ABSTRACT OBJECTIVE To identify the prevalence of back pain among Brazilian school children and the factors associated with this pain. METHODS All 1,720 schoolchildren from the fifth to the eight grade attending schools from the city of Teutonia, RS, Southern Brazil, were invited to participate in the study. From these, 1,597 children participated. We applied the Back Pain and Body Posture Evaluation Instrument. The dependent variable was back pain, while the independent one were demographic, socioeconomic, behavior and heredity data. The prevalence ratio was estimated by multivariate analysis using the Poisson regression model (α = 0.05). RESULTS The prevalence of back pain in the last three months was 55.7% (n = 802). The multivariate analysis showed that back pain is associated with the variables: sex, parents with back pain, weekly frequency of physical activity, daily time spent watching television, studying in bed, sitting posture to write and use the computer, and way of carrying the backpack. CONCLUSIONS The prevalence of back pain in schoolchildren is high and it is associated with demographic, behavior and heredity aspects.

Effects of Single Vs. Multiple Sets during 10 Weeks of Water-based Resistance Training on Neuromuscular Adaptations in Young Women

This study aims to analyze the neuromuscular adaptations of sedentary young women between water-based resistance training performed with single and multiple sets. 66 women (24.72±4.33 years old) were randomly divided into 2 training groups: SS (single set of 30 s) and MS (3 sets of 30 s). Both groups performed 2 sessions per week for 10 weeks. One repetition maximal test (1RM), muscle endurance test (maximal repetitions at 60% 1RM) and muscle power test (squat and countermovement jump performance) were evaluated at pre- and post-training. To compare neuromuscular variables, a repeated measures ANOVA with a group factor (α=0.05) was used. Both groups showed significant increases in 1RM (SS: 14.59%; MS 14.86%), in 60% 1RM (SS: 31.23%; MS: 37.37%), in SJ (SS: 10.9%; MS: 8.3%) and CMJ (SS: 9.1%; MS: 6.8%), without difference between groups. There can be concluded that young and sedentary women presented improvements in different expressions of strength after 10 weeks of training, regardless the volume of training.

Postural education and behavior among students in a city in southern Brazil: student postural education and behavior.

[Purpose] The aim of the present study was to assess the knowledge of the spine and posture among adolescent female students and to determine if they had access to postural education in or outside school. [Subjects and Methods] This was an epidemiological survey of a representative sample of 495 female students aged 14 to 18 years attending a regular secondary school in São Leopoldo, RS, Brazil. Data were collected through a questionnaire. [Results] The results showed that 16.8% of teens did not know what a spine was, 8.3% had no knowledge of posture, and 61% reported receiving no posture education. Posture awareness was associated only with posture while using a computer, while having postural education class was not associated with any postural behavior. [Conclusion] The results showed that, although most students are familiar with the spine and posture, a sizable group is not, and over half had no postural education. These findings suggest that inclusion of postural education programs in schools should be encouraged in order to promote health and prevent diseases related to the spine.

Evaluation of the precision and accuracy of the DIPA software postural assessment protocol

Abstract To evaluate the repeatability and intra- and inter-rater reproducibility of the DIPA protocol for postural evaluation of the frontal and sagittal planes; and to evaluate the validity of the results of evaluating the spine in the sagittal plane using the DIPA software. To evaluate the intra- and inter-rater reproducibility and repeatability (n = 16), the DIPA protocol was conducted on the individuals by three raters, by the same rater on different two occasions and by same rater twice immediately, respectively. To evaluate validity, 54 individuals underwent X-ray evaluation of the spine in the sagittal plane and the DIPA protocol. The Intraclass Correlation Coefficient, the Standard Error of Measurement (SEM) and the Minimum Detectable Change (MDC) were used to evaluate the repeatability and reproducibility; and the Pearson’s correlation test, the independent t test and the Morgan–Pitman’s test were used to evaluate the validity. The knee angle, sagittal and scoliotic arrows presented acceptable levels of correlation, with low SEM and MDC values. When compared to X-ray examination, the results of the DIPA software were excellent, with no significant difference, random error and similar variance between measurements. The DIPA protocol is accurate and precise, and can be used by the same or different raters.

Muscle activation during resistance training with no external load - effects of training status, movement velocity, dominance, and visual feedback

OBJECTIVES To explore the acute effects of training status, movement velocity, dominance, and visual feedback on muscle activation and rating of perceived exertion (RPE) during resistance training with no external load (no-load resistance training; NLRT). METHODS Thirty-three men (17 untrained and 16 trained), performed elbow flexions in four NLRT sessions: 1) slow velocity with EMG visual feedback, 2) slow velocity without EMG visual feedback, 3) fast velocity with EMG feedback, and 4) fast velocity without EMG feedback. RPE was measured using the Borg Discomfort scale. EMG for the biceps and triceps were recorded for both arms. RESULTS EMG feedback had no influence on RPE. The peak and mean EMG values were not different for the biceps (93.8±11.5% and 50±13.1%) and triceps (93.7±23.9% and 49.6±16.2%). The results revealed a difference in the training status, with higher peak EMG for untrained than for trained participants (96.9±20% vs. 90.2±15.6%). However the values for mean EMG were not different between the untrained and trained (50.3±15.7% vs. 49.2±13.7%) participants. There was no difference in the peak (92.8±19% vs. 94.7±20.4%) and mean (49.8±15.0% vs. 49.7±14.5%) EMG values for the dominant and non-dominant sides. Peak EMG values were not different between faster and slower velocities (93.6±19.6% and 93.9±17.8%). However, mean EMG was higher for slower (50.5±14.4%) than for faster (48.5±15.4%) velocities. The peak and mean EMG during contractions with (93.3±17.5% and 49.5±14.1%) and without visual feedback (94.2±19.9% and 50±15.4%) were not significantly different. CONCLUSION NLRT produces high levels of muscle activation independent of training, status, dominance, movement velocity, and visual feedback.

Sexual dysfunction in infertile women: A systematic review and meta-analysis

OBJECTIVE This study aimed to assess the prevalence of sexual dysfunction and Female Sexual Function Index (FSFI) score in women with infertility. STUDY DESIGN A systematic search of the literature was conducted using PubMed, EMBASE, IBECS, and LILACS. The search was limited to articles published from January 2000 to September 2016, without language restriction. Data were analyzed using Stata 12.0. Random effects meta-analyses in weighted mean difference (WMD) were performed for six comparative studies (infertility versus fertility). Heterogeneity was estimated using I2. Moreover, to explore the heterogeneity sources among the studies, meta-regression analyses were also performed. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation guidelines, and risk of bias, with a graphic funnel. RESULTS Meta-analysis was performed in 11 of 13 comparative studies. The result indicated a significant association between an increase in sexual dysfunction and infertility in women (WMD=-0.16, 95% confidence interval=-0.254 to -0.084, p<0.001), and high heterogeneity between studies was noted (I2=98.6%, p<0.000). Meta-regression analysis did not indicate heterogeneity (I2=0.00%). We also performed a meta-analysis of individual FSFI domains in 10 studies. Infertile women had problems with lubrication, orgasm, and satisfaction. Meta-regression analysis also showed that heterogeneity had no influence on the final results of all the analyses. CONCLUSIONS Infertility was associated with an increase in female sexual dysfunction. The most affected areas of sexual function were lubrication, orgasm, and satisfaction.

Adaptation and validation of body maps for musculoskeletal pain location in patients with severe obesity

Background Although a variety of instruments implement body maps for the precise identification of pain symptoms, no instrument has been validated for use in people with obesity. This study reports the adaptation and validation of body maps for musculoskeletal pain location in people with obesity. Methods Nine key anatomical regions were highlighted based on the original images of the Nordic Musculoskeletal Questionnaire body maps. Adult silhouettes were generated from photographs of men and women with obesity. The body dimensions were adjusted to take into account the different body fat distribution patterns of people with obesity. The validity of the images was assessed by 12 experts. Subsequently, a data collection stage was performed with 58 patients with severe obesity from both sexes. The reproducibility of the images was tested by comparison with the original images. Results The results of the validation pilot study indicated that the adapted images facilitated the location of musculoskeletal pain in men and women with obesity. The reproducibility of the original and adapted versions of the body maps indicated good agreement for pain over the last 12 months and 7 days (80% vs. 79.7%). Pain scores in the last 12 months indicated good and high sensitivity and specificity for all body areas (60.9% vs. 89.1%). Considering pain in the last 7 days, high sensitivity and specificity for all areas of the body (85.1% vs. 70.1%). Conclusions The body maps developed in this study are reliable and valid to identify the location of pain in people with obesity.