Borgen, J. (2014). The LEAF questionnaire: a screening tool for the identification of female athletes at risk for the female athlete triad.

The female athlete triad (Triad), links low energy availability (EA), with menstrual dysfunction (MD), and impaired bone health. The aims of this study were to examine associations between EA/MD and energy metabolism and the prevalence of Triad-associated conditions in endurance athletes. Forty women [26.2 ± 5.5 years, body mass index (BMI) 20.6 ± 2.0 kg/m(2), body fat 20.0 ± 3.0%], exercising 11.4 ± 4.5 h/week, were recruited from national teams and competitive clubs. Protocol included gynecological examination; assessment of bone health; indirect respiratory calorimetry; diet and exercise measured 7 days to assess EA; eating disorder (ED) examination; blood analysis. Subjects with low/reduced EA (< 45 kcal/kg FFM/day), had lower resting metabolic rate (RMR) compared with those with optimal EA [28.4 ± 2.0 kcal/kg fat-free mass (FFM)/day vs 30.5 ± 2.2 kcal/kg FFM/day, P < 0.01], as did subjects with MD compared with eumenorrheic subjects (28.6 ± 2.4 kcal/kg FFM/day vs 30.2 ± 1.8 kcal/kg FFM/day, P < 0.05). 63% had low/reduced EA, 25% ED, 60% MD, 45% impaired bone health, and 23% had all three Triad conditions. 53% had low RMR, 25% hypercholesterolemia, and 38% hypoglycemia. Conclusively, athletes with low/reduced EA and/or MD had lowered RMR. Triad-associated conditions were common in this group of athletes, despite a normal BMI range. The high prevalence of ED, MD, and impaired bone health emphasizes the importance of prevention, early detection, and treatment of energy deficiency.

Total daily energy expenditure (“total expenditure”) reflects daily energy needs and is a critical variable in human health and physiology, but its trajectory over the life course is poorly studied. We analyzed a large, diverse database of total expenditure measured by the doubly labeled water method for males and females aged 8 days to 95 years. Total expenditure increased with fat-free mass in a power-law manner, with four distinct life stages. Fat-free mass–adjusted expenditure accelerates rapidly in neonates to ~50% above adult values at ~1 year; declines slowly to adult levels by ~20 years; remains stable in adulthood (20 to 60 years), even during pregnancy; then declines in older adults. These changes shed light on human development and aging and should help shape nutrition and health strategies across the life span.

A diet-induced negative energy balance triggers compensatory mechanisms, e.g., lower metabolic rate and increased appetite. However, knowledge about potential compensatory mechanisms triggered by increased aerobic exercise is limited. A randomized controlled trial was performed in healthy, sedentary, moderately overweight young men to examine the effects of increasing doses of aerobic exercise on body composition, accumulated energy balance, and the degree of compensation. Eighteen participants were randomized to a continuous sedentary control group, 21 to a moderate-exercise (MOD; 300 kcal/day), and 22 to a high-exercise (HIGH; 600 kcal/day) group for 13 wk, corresponding to ϳ30 and 60 min of daily aerobic exercise, respectively. Body weight (MOD: Ϫ3.6 kg, P Ͻ 0.001; HIGH: Ϫ2.7 kg, P ϭ 0.01) and fat mass (MOD: Ϫ4.0 kg, P Ͻ 0.001 and HIGH: Ϫ3.8 kg, P Ͻ 0.001) decreased similarly in both exercise groups. Although the exercise-induced energy expenditure in HIGH was twice that of MOD, the resulting accumulated energy balance, calculated from changes in body composition, was not different (MOD: Ϫ39.6 Mcal, HIGH: Ϫ34.3 Mcal, not significant). Energy balance was 83% more negative than expected in MOD, while it was 20% less negative than expected in HIGH. No statistically significant changes were found in energy intake or nonexercise physical activity that could explain the different compensatory responses associated with 30 vs. 60 min of daily aerobic exercise. In conclusion, a similar body fat loss was obtained regardless of exercise dose. A moderate dose of exercise induced a markedly greater than expected negative energy balance, while a higher dose induced a small but quantifiable degree of compensation.exercise; body weight regulation; compensatory mechanisms; energy balance ALTHOUGH A MODERN SEDENTARY lifestyle along with overeating has been put forward as "Big Two" factors in the etiology of obesity (3,10,29), the outcomes of structured exercise programs designed to promote weight loss are often modest (42,58). This has led to the general (mis)conception that exercise, in itself, is a poor weight management strategy (20,42,49). Apart from a potential lack of compliance, the discrepancy between predicted and observed weight loss is likely due to a combination of physiological and behavioral compensatory changes affecting energy balance. These compensatory changes cause the accumulated energy balance during an exercise intervention to be less negative than would be theoretically predicted from the exercise-induced energy expenditure (ExEE), i.e., the total amount of energy expenditure that is caused by the exercise intervention (12,32,34).Body energy stores are protected against long-term negative energy balance resulting from caloric restriction by a greater than predicted reduction in resting energy expenditure (REE) (28), a decrease in nonexercise activity thermogenesis (NEAT) (40,45), an increase in the metabolic efficiency of physical activity (16,35), and an increase in hedonic (21) and hormonal mediators o...

SummaryAchieving body-weight stability is certainly challenging in today's obesogenic environment. Every day we are surrounded and affected by stimuli that act on our behaviour. A common feature of these stimuli is that they increase our comfort and well-being, but unfortunately they promote a positive caloric balance. Intriguingly, the preponderance of sedentary lifestyles is not only a matter of the amount of calories expended. A careful examination of modern sedentary activities reveals that they also promote overconsumption of food. This is particularly the case with television viewing, video game playing, cognitive working, music listening and short sleeping. Moreover, the increased food intake in the absence of hunger observed with the practice of these modern-life activities emphasizes that the hedonic value of food intake plays an important role. These observations suggest that our quest for reward and pleasure is not fine tuned to our biology, and the development of coping strategies is needed.

Total PA, MVPA and sleep duration were independently associated with FMI, and combined associations of movement behaviors showed a synergistic effect with FMI. In the longitudinal study design, a high FMI at baseline was associated with lower PA and higher sedentary time after 200 days but not vice versa, even in normal-weight children. Our results suggest that adiposity is a better predictor of PA and sedentary behavior changes than the other way around.

Background: Video game playing has been linked to obesity in many observational studies. However, the influence of this sedentary activity on food intake is unknown. Objective: The objective was to examine the acute effects of sedentary video game play on various components of energy balance. Design: With the use of a randomized crossover design, 22 healthy, normal-weight, male adolescents (mean 6 SD age: 16.7 6 1.1 y) completed two 1-h experimental conditions, namely video game play and rest in a sitting position, followed by an ad libitum lunch. The endpoints were spontaneous food intake, energy expenditure, stress markers, appetite sensations, and profiles of appetite-related hormones. Results: Heart rate, systolic and diastolic blood pressures, sympathetic tone, and mental workload were significantly higher during the video game play condition than during the resting condition (P , 0.05). Although energy expenditure was significantly higher during video game play than during rest (mean increase over resting: 89 kJ; P , 0.01), ad libitum energy intake after video game play exceeded that measured after rest by 335 kJ (P , 0.05). A daily energy surplus of 682 kJ (163 kcal) over resting (P , 0.01) was observed in the video game play condition. The increase in food intake associated with video game play was observed without increased sensations of hunger and was not compensated for during the rest of the day. Finally, the profiles of glucose, insulin, cortisol, and ghrelin did not suggest an up-regulation of appetite during the video game play condition. Conclusion: A single session of video game play in healthy male adolescents is associated with an increased food intake, regardless of appetite sensations. The trial was registered at clinicaltrials.gov as NCT01013246.

BackgroundAs cardio-metabolic risk tracks from childhood to adulthood, a better understanding of the relationship between movement behaviors (physical activity, sedentary behavior and sleep) and cardio-metabolic risk in childhood may aid in preventing metabolic syndrome (MetS) in adulthood.ObjectiveTo examine independent and combined cross-sectional and longitudinal associations between movement behaviors and the MetS score in 8-11 year old Danish children.DesignPhysical activity, sedentary time and sleep duration (seven days and eight nights) were assessed by accelerometer and fat mass index (fat mass/height2) was assessed using Dual-energy X-ray absorptiometry. The MetS-score was based on z-scores of waist circumference, mean arterial blood pressure, homeostatic model assessment of insulin resistance, triglycerides and high density lipoprotein cholesterol. All measurements were taken at three time points separated by 100 days. Average of the three measurements was used as habitual behavior in the cross-sectional analysis and changes from first to third measurement was used in the longitudinal analysis.Results723 children were included. In the cross-sectional analysis, physical activity was negatively associated with the MetS-score (P<0.03). In the longitudinal analysis, low physical activity and high sedentary time were associated with an increased MetS-score (all P<0.005); however, after mutual adjustments for movement behaviors, physical activity and sleep duration, but not sedentary time, were associated with the MetS-score (all P<0.03). Further adjusting for fat mass index while removing waist circumference from the MetS-score rendered the associations no longer statistically significant (all P>0.17). Children in the most favorable tertiles of changes in moderate-to-vigorous physical activity, sleep duration and sedentary time during the 200-day follow-up period had an improved MetS-score relative to children in the opposite tertiles (P = 0.005).ConclusionThe present findings indicate that physical activity, sedentary time and sleep duration should all be targeted to improve cardio-metabolic risk markers in childhood; this is possibly mediated by adiposity.