Duration, frequency, and types of children’s activities: potential of a classification procedure

This study investigated the potential of a classification procedure to determine type, duration, and frequency of children's physical activity (PA) during 7 days based on accelerometer data. Hip and wrist accelerometer data (1-second epoch) were collected over a week in 41 children (age: 10.7 ± 0.9 years). The classification procedure was used to assign each second into one of the following four categories: stationary activities, walking, running, and jumping. A diary was used to assess the simultaneous activity setting. Children spent 75.5% of the time (600.9 ± 80.1 minutes/day) on stationary activities, 15.6% (124.6 ± 33.6 minutes/day) on walking, 2% (16.1 ± 8.6 minutes/day) on running, and 1% (4.7 ± 5.2 minutes/day) on jumping. The median duration of stationary activities, walking, running, and jumping was 4, 2, 1, and 1 seconds, respectively. The largest proportion of running and jumping occurred during outdoor sport training (10.7%), physical education classes (6.7%), and vigorous outdoor activity (6.1%). The classification procedure used in this study shows the potential for analyzing children's PA in free-living conditions. The study results revealed that children's PA is characterized by very short activity bouts and that providing the possibility for children to participate in structured or unstructured outdoor activities might increase their PA. Therefore, the classification procedure enhanced the analysis of the transitory nature of children's PA and the understanding of their PA behavior during different activity settings

Total Energy Expenditure, Energy Intake, and Body Composition in Endurance Athletes Across the Training Season: a Systematic Review

Background: Endurance athletes perform periodized training in order to prepare for main competitions and maximize performance. However, the coupling between alterations of total energy expenditure (TEE), energy intake, and body composition during different seasonal training phases is unclear. So far, no systematic review has assessed fluctuations in TEE, energy intake, and/or body composition in endurance athletes across the training season. The purpose of this study was to (1) systematically analyze TEE, energy intake, and body composition in highly trained athletes of various endurance disciplines and of both sexes and (2) analyze fluctuations in these parameters across the training season. Methods: An electronic database search was conducted on the SPORTDiscus and MEDLINE (January 1990–31 January 2015) databases using a combination of relevant keywords. Two independent reviewers identified potentially relevant studies. Where a consensus was not reached, a third reviewer was consulted. Original research articles that examined TEE, energy intake, and/or body composition in 18–40-year-old endurance athletes and reported the seasonal training phases of data assessment were included in the review. Articles were excluded if body composition was assessed by skinfold measurements, TEE was assessed by questionnaires, or data could not be split between the sexes. Two reviewers assessed the quality of studies independently. Data on subject characteristics, TEE, energy intake, and/or body composition were extracted from the included studies. Subjects were categorized according to their sex and endurance discipline and each study allocated a weight within categories based on the number of subjects assessed. Extracted data were used to calculate weighted means and standard deviations for parameters of TEE, energy intake, and/or body composition. Results: From 3589 citations, 321 articles were identified as potentially relevant, with 82 meeting all of the inclusion criteria. TEE of endurance athletes was significantly higher during the competition phase than during the preparation phase (p < 0.001). During the competition phase, both body mass and fat-free mass were significantly higher compared to other seasonal training phases (p < 0.05). Conclusions: Limitations of the present study included insufficient data being available for all seasonal training phases and thus low explanatory power of single parameters. Additionally, the classification of the different seasonal training phases has to be discussed. Male and female endurance athletes show important training seasonal fluctuations in TEE, energy intake, and body composition. Therefore, dietary intake recommendations should take into consideration other factors including the actual training load, TEE, and body composition goals of the athlete

Serum leptin and risk of cognitive decline in elderly italians.

Background: US studies suggest that leptin, a fat-derived hormone, may be protective against the development of dementia. Objective: To investigate the complex relationship between leptin levels and cognitive decline in elderly Italians. Methods: We studied circulating fasting leptin levels in 809 elderly adults free from dementia who participated in the prospective Italian population-based InCHIANTI study between 1998 and 2009 (mean follow-up of 8.0 years). Global cognitive decline was defined as a reduction of ≥5 points on the Mini-Mental State Examination (MMSE). Trail-Making Tests A and B were also incorporated, with cognitive decline defined as discontinued testing or the worst 10% of change from baseline. We also investigated whether any association could be explained by midlife weight and whether cognitive decline was associated with changing leptin levels. Results: The multivariate adjusted relative risk ([RR]; 95% confidence interval [CI]) of cognitive decline on the MMSE was 0.84 (95% CI 0.73–0.97) in relation to baseline sex-standardized log-leptin levels. High leptin levels showed a non-significant trend toward a reduced risk of decline on the Trail-Making Tests A (RR = 0.85, 95% CI 0.71–1.02) and B (RR = 0.90, 0.79–1.02). Adjusting for midlife weight or change in weight did not alter the pattern of results, and cognitive decline was not associated with changing leptin levels. Conclusions: High leptin levels were independently associated with a reduced risk of cognitive decline in elderly Italians.Italian Ministry of HealthU.S. National Institute on AgingAlzheimer’s AssociationNational Institute for Health Research (NIHR)National Institute of Health (Baltimore)National Institute of Health (Maryland)Mary Kinross Charitable TrustJames Tudor FoundationHalpin TrustSir Halley Stewart TrustAge Related Diseases and Health TrustNorman Family Charitable Trus

Obesity in Older People With and Without Conditions Associated With Weight Loss: Follow-up of 955,000 Primary Care Patients.

BACKGROUND: Moderate obesity in later life may improve survival, prompting calls to revise obesity control policies. However, this obesity paradox may be due to confounding from smoking, diseases causing weight-loss, plus varying follow-up periods. We aimed to estimate body mass index (BMI) associations with mortality, incident type 2 diabetes, and coronary heart disease in older people with and without the above confounders. METHODS: Cohort analysis in Clinical Practice Research Datalink primary care, hospital and death certificate electronic medical records in England for ages 60 to more than 85 years. Models were adjusted for age, gender, alcohol use, smoking, calendar year, and socioeconomic status. RESULTS: Overall, BMI 30-34.9 (obesity class 1) was associated with lower overall death rates in all age groups. However, after excluding the specific confounders and follow-up less than 4 years, BMI mortality risk curves at age 65-69 were U-shaped, with raised risks at lower BMIs, a nadir between 23 and 26.9 and steeply rising risks above. In older age groups, mortality nadirs were at modestly higher BMIs (all <30) and risk slopes at higher BMIs were less marked, becoming nonsignificant at age 85 and older. Incidence of diabetes was raised for obesity-1 at all ages and for coronary heart disease to age 84. CONCLUSIONS: Obesity is associated with shorter survival plus higher incidence of coronary heart disease and type 2 diabetes in older populations after accounting for the studied confounders, at least to age 84. These results cast doubt on calls to revise obesity control policies based on the claimed risk paradox at older ages

Respiratory quotient evolution during normal pregnancy: what nutritional or clinical information can we get out of it?

Food intake increases to a varying extent during pregnancy to provide extra energy for the growing fetus. Measuring the respiratory quotient (RQ) during the course of pregnancy (by quantifying O2 consumption and CO2 production with indirect calorimetry) could be potentially useful since it gives an insight into the evolution of the proportion of carbohydrate vs. fat oxidized during pregnancy and thus allows recommendations on macronutrients for achieving a balanced (or slightly positive) substrate intake. A systematic search of the literature for papers reporting RQ changes during normal pregnancy identified 10 papers reporting original research. The existing evidence supports an increased RQ of varying magnitude in the third trimester of pregnancy, while the discrepant results reported for the first and second trimesters (i.e. no increase in RQ), explained by limited statistical power (small sample size) or fragmentary data, preclude safe conclusions about the evolution of RQ during early pregnancy. From a clinical point of view, measuring RQ during pregnancy requires not only sophisticated and costly indirect calorimeters but appears of limited value outside pure research projects, because of several confounding variables: (1) spontaneous changes in food intake and food composition during the course of pregnancy (which influence RQ); (2) inter-individual differences in weight gain and composition of tissue growth; (3) technical factors, notwithstanding the relatively small contribution of fetal metabolism per se (RQ close to 1.0) to overall metabolism of the pregnant mother

Physical activity: the health benefits outweigh the risks

This article will summarize the current findings on the effects of physical activity on human health and well-being.; Physical activity is associated with enhanced health and reduced risk of all-cause mortality such as cardiovascular disease, hypertension, type 2 diabetes, obesity, osteoporosis, sarcopenia, cognitive disorders, and some forms of cancer. Nevertheless, the effects of exercise with respect to potential health consequences are complex. When untrained or previously sedentary persons undertake vigorous exertion suddenly, the undesired side effects of injuries, dehydration or cardiac arrest are amplified.; It is reasonable to conclude that the risk exposure through physical activity is outweighed by its overall benefits, and health authorities strongly encourage participation in moderate intensity physical activity on a daily basis. In the future, the identification and characterization of particularly inactive sub-groups of the population may facilitate and optimize the planning of public health interventions

Energy and macronutrient requirements for physical fitness in exercising subjects

Optimal nutritional intakes are critical for health- and skill-related physical fitness. This review details the effect of energy restriction and supplementation on physical fitness, discusses the optimal chronic macronutrient intakes for physical fitness in exercising subjects and finally overviews the impact of short-term intakes of carbohydrate and protein, before, during and after exercise, on physical fitness of athletes. The present standings highlight that it is essential that health care givers personalize nutritional advice to meet the specific needs of exercising individuals while applying the described recommendations. It reminds the difficulty of providing straight nutritional recommendations for physical fitness on the basis of evidence-based medicine

Energy and macronutrient requirements for physical fitness in exercising subjects

Optimal nutritional intakes are critical for health- and skill-related physical fitness. This review details the effect of energy restriction and supplementation on physical fitness, discusses the optimal chronic macronutrient intakes for physical fitness in exercising subjects and finally overviews the impact of short-term intakes of carbohydrate and protein, before, during and after exercise, on physical fitness of athletes. The present standings highlight that it is essential that health care givers personalize nutritional advice to meet the specific needs of exercising individuals while applying the described recommendations. It reminds the difficulty of providing straight nutritional recommendations for physical fitness on the basis of evidence-based medicine

Effects of physical activity on food intake

The understanding of the effect of physical activity (PA) on food intake is imperative for considering PA as an additional tool for prevention and treatment of many diseases. Prolonged strenuous PA performed on a regular basis causes an increase in overall energy turnover, and leads either to loss of body weight, or to an increased food intake. When leading to loss of body weight, PA may be used as a therapeutic adjunct in the treatment of obesity. When increasing food intake to compensate for increased energy expenditure and maintaining body weight, PA, by increasing intake of other constituents of food like minerals and vitamins, may contribute to micronutrient deficiency coverage. However, the type of activity, as well as body composition of the individuals engaging in sport, play an important role in food intake regulation and its changes with time. Some studies indicate that short-term exercise does not have the same effect on food intake as long-term exercise and that eventual increase in food intake due to increased PA does not follow the same pattern in obese as in lean individuals. To better understand the relationship between PA on food intake, current findings on this topic will be summarized in this paper