Strength Training for Children and Adolescents: Benefits and Risks

Physical activity has proved to be an effective means of preventing several diseases and improving general health. In most cases, though, light to moderate efforts are suggested, for both youngsters and adults. Common sense advices call for late inception of intense, strength training-related activities, like weight lifting and plyometrics, which are usually postponed at the end of the growth age, even among sport practitioners. However, such advices seem to have a mainly anecdotal nature. The purpose of this review is to evaluate risks and benefits of early inception of strength training, at adolescence or even earlier, and to verify whether concerns can be grounded scientifically. Current literature does not seem to have any particular aversion against the practice of strength training by children and adolescents, provided that some safety rules are followed, like medical clearance, proper instruction from a qualified professional and progressive overload. At the same time, several studies provide consistent findings supporting the benefits of repeated, intense physical efforts in young subjects. Improved motor skills and body composition, in terms of increased fat free mass, reduced fat mass and enhanced bone health, have been extensively documented, especially if sport practice began early, when the subjects were pubescent. It can be therefore concluded that strength training is a relatively safe and healthy practice for children and adolescents

Strength Training for Children and Adolescents: Benefits and Risks

Physical activity has proved to be an effective means of preventing several diseases and improving general health. In most cases, though, light to moderate efforts are suggested, for both youngsters and adults. Common sense advices call for late inception of intense, strength training-related activities, like weight lifting and plyometrics, which are usually postponed at the end of the growth age, even among sport practitioners. However, such advices seem to have a mainly anecdotal nature. The purpose of this review is to evaluate risks and benefits of early inception of strength training, at adolescence or even earlier, and to verify whether concerns can be grounded scientifically. Current literature does not seem to have any particular aversion against the practice of strength training by children and adolescents, provided that some safety rules are followed, like medical clearance, proper instruction from a qualified professional and progressive overload. At the same time, several studies provide consistent findings supporting the benefits of repeated, intense physical efforts in young subjects. Improved motor skills and body composition, in terms of increased fat free mass, reduced fat mass and enhanced bone health, have been extensively documented, especially if sport practice began early, when the subjects were pubescent. It can be therefore concluded that strength training is a relatively safe and healthy practice for children and adolescents

Current immigration to Europe from North Africa. Health and physical activity

Immigration to Europe - especially from neighbouring North Africa - is a consistent phenomenon with social and health-related implications. Even if in many cases immigrants come from lower-income countries, their health status is better than that of European-born citizens at immigration time, given their younger age. Still, the adoption of a Western life style, with increased caloric intake and reduced physical activity, may soon lead to a deterioration of individual health. European-born individuals engage more often in leisure-time physical activity than immigrants (especially women) and follow a more healthy diet. Thus, obesity, cardiovascular diseases and diabetes may have a higher prevalence in accustomed immigrants

Age at Menarche, Growth Velocity, and Adiposity Indices in Italian Girls Aged 10 to 14

Age at menarche (AAM) is an effective marker of puberty timing but its onset could be influenced by several intrinsic and extrinsic factors. This study aimed to assess the AAM in a sample of Italian adolescents and to investigate its association with anthropometric variables. Considering the rise in overweight/obesity worldwide, special attention was paid to a possible decrease in AAM as adiposity indices increase. A longitudinal study was carried out on 117 middle school girls in Northern Italy. Data concerning menarche and anthropometric traits (standing and sitting height, weight, waist circumference, and skinfold thicknesses) were directly collected. Lower limb length and indices of adiposity and growth were calculated. The median AAM was 11.66 (95% IC: 11.31-11.68). Age-adjusted ANCOVA between mature and non-mature girls showed significant differences in growth-related traits and WHtR. No preponderance of overweight/obesity among mature participants was found. AAM was not significantly associated with weight or the growth velocity of adiposity indices in a subsample of maturers. Moreover, the median AAM of our sample was similar to that found in women born about 60 years ago in the same region. In conclusion, in addition to a stabilization of AAM since the 1960s, our results suggest that there is no significant correlation between increased adiposity and early AAM

Prediction of bench press performance in powerlifting: The role of upper limb anthropometry

The bench press (BP) is a complex, multiarticular exercise known as one of the three powerlifting specialties. Although several variables contribute to the maximum load lifted, upper limb variables may also play an important role in BP performance. In this study, a cohort of 47 male Italian classic powerlifters underwent a direct anthropometric evaluation during two official competitions. The recorded parameters included body mass index, body composition, and variables of the upper limb (indirectly evaluated cross-sectional areas and lengths). IPF-GL points and maximal strength (1RM) adjusted for weight were used as proxies for performance. Statistical comparisons between weaker and stronger powerlifters, Pearson correlation and partial correlation analyses, and multiple linear regression models were performed. The upper arm cross muscular area (r = 0.56) and fat-free mass (r = 0.31) were positively correlated with Wilks points, whereas the arm fat index was negatively correlated with 1RM BP (r = -0.37). Moreover, we proposed two new indices (UALR and UAMR) that represent the ratio between upper arm areas and length. Both univariate and multivariate analyses confirmed the strong association between these two variables and BP performance. Further improvement of this study may confirm the important role of body proportion and body composition as predictors of performance in strength sports

Assessing the Impact of COVID-19 Prevention Measures on Adolescent Growth in Italy

COVID-19 infection has caused increased morbidity and mortality worldwide. Several strategies have been adopted around the world to prevent its spread. Italy underwent a long lockdown for face-to-face educational activities, which were replaced with online classes. This longitudinal study aimed to analyze the effects of COVID-19 prevention measures on physical growth and body image perception in a sample of Italian adolescents who experienced the pandemic-induced lockdown in 2020. In particular, we wished to ascertain how lifestyle changes had affected their growth rates and health. Special attention was paid to increases in adiposity indicators (BMI, waist circumference, waist-to-height ratio) and weight caused by reduced physical activity, and consequent possible dissatisfaction with body image. We assessed the impact of school closures by comparing the annual growth rate and body image perception changes of adolescents (n = 60; age = 11.3 & PLUSMN; 0.4 years) who experienced this isolation with those in the following years who did not experience these restrictions (n = 68; age = 11.4 & PLUSMN; 0.3 years). As a consequence of the lockdown, our results indicate a greater annual growth rate in weight and other indices of adiposity (p < 0.05). As the virus is continuing to evolve and propagate, larger population studies can verify and confirm our findings. In promoting health policy to prevent the ongoing prevalence of obesity in adolescents, an accurate assessment of whether the increase in obesity rates during the pandemic is to be considered a temporary trend is highly recommended

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

Effects of breastfeeding and weaning practices on growth

The relationships between length or weight and type of feeding or weaning practices during the first 12 months of life for a cohort of 629 infants were examined. The results of analysis of variance and correlation showed that there was a significant relationship between weight and type or length of lactation. Some indication of an influence of weaning period start was also suggested