Energy expenditure and dietary intake in professional football players in the Dutch Premier League: Implications for nutritional counselling.

Selecting effective dietary strategies for professional football players requires comprehensive information on their energy expenditure (EE) and dietary intake. This observational study aimed to assess EE and dietary intake over a 14-day period in a representative group (n = 41) of professional football players playing in the Dutch Premier League (Eredivisie). Daily EE, as assessed by doubly labelled water, was 13.8 ± 1.5 MJ/day, representing a physical activity level (PAL) of 1.75 ± 0.13. Weighted mean energy intake (EI), as assessed by three face-to-face 24-h recalls, was 11.1 ± 2.9 MJ/day, indicating 18 ± 15% underreporting of EI. Daily EI was higher on match days (13.1 ± 4.1 MJ) compared with training (11.1 ± 3.4 MJ; P < 0.01) and rest days (10.5 ± 3.1 MJ; P < 0.001). Daily carbohydrate intake was significantly higher during match days (5.1 ± 1.7 g/kg body mass (BM)) compared with training (3.9 ± 1.5 g/kg BM; P < 0.001) and rest days (3.7 ± 1.4 g/kg BM; P < 0.001). Weighted mean protein intake was 1.7 ± 0.5 g/kg BM. Daytime distribution of protein intake was skewed, with lowest intakes at breakfast and highest at dinner. In conclusion, daily EE and PAL of professional football players are modest. Daily carbohydrate intake should be increased to maximize performance and recovery. Daily protein intake seems more than adequate, but could be distributed more evenly throughout the day.

Validation of the doubly labeled water method using off-axis integrated cavity output spectroscopy and isotope ratio mass spectrometry.

When the doubly labeled water (DLW) method is used to measure total daily energy expenditure (TDEE), isotope measurements are typically performed using isotope ratio mass spectrometry (IRMS). New technologies, such as off-axis integrated cavity output spectroscopy (OA-ICOS) provide comparable isotopic measurements of standard waters and human urine samples, but the accuracy of carbon dioxide production (V̇co2) determined with OA-ICOS has not been demonstrated. We compared simultaneous measurement V̇co2 obtained using whole-room indirect calorimetry (IC) with DLW-based measurements from IRMS and OA-ICOS. Seventeen subjects (10 female; 22 to 63 yr) were studied for 7 consecutive days in the IC. Subjects consumed a dose of 0.25 g H218O (98% APE) and 0.14 g 2H2O (99.8% APE) per kilogram of total body water, and urine samples were obtained on days 1 and 8 to measure average daily V̇co2 using OA-ICOS and IRMS. V̇co2 was calculated using both the plateau and intercept methods. There were no differences in V̇co2 measured by OA-ICOS or IRMS compared with IC when the plateau method was used. When the intercept method was used, V̇co2 using OA-ICOS did not differ from IC, but V̇co2 measured using IRMS was significantly lower than IC. Accuracy (~1-5%), precision (~8%), intraclass correlation coefficients ( R = 0.87-90), and root mean squared error (30-40 liters/day) of V̇co2 measured by OA-ICOS and IRMS were similar. Both OA-ICOS and IRMS produced measurements of V̇co2 with comparable accuracy and precision compared with IC.

Growth and endothelial function in the first 2 years of life.

OBJECTIVE: To test the hypothesis that the inverse association between infant growth and endothelial function at 6 months would persist to 24 months and that accelerated growth would lead to an increased percent body fat, which would, in turn, impact negatively on endothelial function. STUDY DESIGN: In a prospective observational study, 104 healthy term newborns underwent anthropometry and measurements of vascular vasodilation at 0, 6, 12, and 24 months. We recorded maximum vasodilation in response to acetylcholine (endothelium-dependent) and nitroprusside (endothelium-independent) by use of laser-Doppler vascular perfusion monitoring of the forearm skin vasculature. Additional anthropometry at 1 and 3 months was collected from child welfare centers. The data were analyzed by multilevel linear regression. RESULTS: Weight gain from 0-1 month was associated inversely with maximum perfusion in response to acetylcholine at the age of 2 years (b = -8.28 perfusion units [PU] per Δ z-score, P = .03). Weight gain from 0-1 month was related positively to maximum perfusion in response to nitroprusside (b = 10.12 PU per Δ z-score, P = .04), as was birth weight (b = 8.02 PU per z-score, P = .02). Body fat percentage did not have a significant effect in any of the perfusion models and was not related to maximum perfusion at 2 years. CONCLUSION: Infant weight gain from 0-1 month is inversely related to endothelial function in healthy term infants, at least to the age of 2 years. This relationship was not explained by an increased percentage body fat.

Oral Motor Impairments Contribute to Weight Status of Adults with Severe Cerebral Palsy.

Adults with severe cerebral palsy (CP) are susceptible to malnutrition and metabolic disorders due to limited daily physical activity and challenges related to eating. We hypothesized that the condition of being underweight arises from inadequate energy intake due to difficulties in eating, rather than heightened total energy expenditure or an elevated resting metabolic rate. The present study encompassed 17 adults with severe CP (classified as GMFSC III-V). Energy intake, utilization, and expenditure were gauged via thorough dietary recordings and double-labeled water (DLW) analyses. Resting metabolic rates were assessed through indirect calorimetry, and metabolic health was investigated via blood samples. Oral motor function, eating assessment during meals, and weight fluctuations throughout the experimental period were also evaluated. We found significant correlations between weight, oral impairments (p < 0.01), and eating difficulties (p < 0.05). While total energy expenditure and daily consumption were similar between underweight (UW) and overweight (OW) individuals, significant variability in both expenditure and intake was evident within the UW group. Particularly, those with lower BMIs experienced heightened mealtime impairments and complications. Our present findings indicate that eating difficulties are the central concern for UW status in this population.

Energy Expenditure during Extreme Endurance Exercise: The Giro d'Italia.

PURPOSE: Little data are available on doubly labeled water (DLW) assessed total daily energy expenditure (TDEE) during extreme endurance exercise. Doubly labeled water is considered the gold standard to measure TDEE, but different calculations are being used, which may have a large impact on the results. The aim of the current study was to measure TDEE during the Giro d'Italia and apply two different calculation methods. METHODS: Seven male cyclists (age, 28 ± 5 yr; body mass index, 22.1 ± 2.1 kg·m) completed the 24-d professional cycling race "Giro d'Italia" in which a total distance of 3445 km was covered, including 10 mountain stages. Total daily energy expenditure was measured over the entire duration of the race, with the ingestion of DLW at three different time points. To calculate TDEE and body composition, the isotope dilution space was calculated using two different techniques, the "plateau" and "intercept" technique. RESULTS: The %fat mass at baseline was 7.8% and 16.8% with the plateau and intercept technique respectively and did not significantly change over the course of the race. Total daily energy expenditure was on average 32.3 ± 3.4 MJ·d using the plateau technique versus 28.9 ± 3.2 using the intercept technique, resulting in an average physical activity level (PAL) of 4.37 ± 0.43 versus 3.91 ± 0.39, respectively. The dilution space ratio was on average 1.030 with the plateau and 1.060 with the intercept technique. CONCLUSIONS: Given that the observed dilution space ratio with the plateau technique is similar as the expected ratio from literature and the % fat mass of 7.8% is more realistic for the athletes being studied, we propose the application of the plateau rather than the intercept method, when using DLW during extreme endurance exercise.

Evaluation of wireless determination of skin temperature using iButtons.

Measurements of skin temperatures are often complicated because of the use of wired sensors. This is so in field studies, but also holds for many laboratory conditions. This article describes a wireless temperature system for human skin temperature measurements, i.e. the Thermochron iButton DS1291H. The study deals with validation of the iButton and its application on the human skin, and describes clinical and field measurements. The validation study shows that iButtons have a mean accuracy of -0.09 degrees C (-0.4 degrees C at most) with a precision of 0.05 degrees C (0.09 degrees C at most). These properties can be improved by using calibration. Due to the size of the device the response time is longer than that of conventional sensors, with a tau in water of 19 s. On the human skin under transient conditions the response time is significantly longer, revealing momentary deviations with a magnitude of 1 degrees C. The use of iButtons has been described in studies on circadian rhythms, sleep and cardiac surgery. With respect to circadian rhythm and sleep research, skin temperature assessment by iButtons is of significant value in laboratory, clinical and home situations. We demonstrate that differences in laboratory and field measurements add to our understanding of thermophysiology under natural living conditions. The advantage of iButtons in surgery research is that they are easy to sterilize and wireless so that they do not hinder the surgical procedure. In conclusion, the application of iButtons is advantageous for measuring skin temperatures in those situations in which wired instruments are unpractical and fast responses are not required.

Dietary restraint and control over "wanting" following consumption of "forbidden" food.

Eating behavior can be influenced by the rewarding value of food, i.e., "liking" and "wanting." The objective of this study was to assess in normal-weight dietary restrained (NR) vs. unrestrained (NU) eaters how rewarding value of food is affected by satiety, and by eating a nonhealthy perceived, dessert-specific food vs. a healthy perceived, neutral food (chocolate mousse vs. cottage cheese). Subjects (24NR age = 25.0 ± 8.2 years, BMI = 22.3 ± 2.1 kg/m(2); 26NU age = 24.8 ± 8.0 years, BMI = 22.1 ± 1.7 kg/m(2)) came to the university twice, fasted (randomized crossover design). Per test-session "liking" and "wanting" for 72 items divided in six categories (bread, filling, drinks, dessert, sweets, stationery (placebo)) was measured, before and after consumption of chocolate mousse/cottage cheese, matched for energy content (5.6 kJ/g) and individual daily energy requirements (10%). Chocolate mousse was liked more than cottage cheese (P < 0.05). After consumption of chocolate mousse or cottage cheese, appetite and "liking" vs. placebo were decreased in NR and NU (P < 0.03), whereas "wanting" was only decreased in NR vs. NU (P ≤ 0.01). In NR vs. NU "wanting" was specifically decreased after chocolate mousse vs. cottage cheese; this decrease concerned especially "wanting" for bread and filling (P < 0.05). To conclude, despite similar decreases in appetite and "liking" after a meal in NR and NU, NR decrease "wanting" in contrast to NU. NR decrease "wanting" specifically for a nonhealthy perceived, "delicious," dessert-specific food vs. a nutritional identical, yet healthy perceived, slightly less "delicious," "neutral" food. A healthy perceived food may thus impose greater risk for control of energy intake in NR.

Eating what you like induces a stronger decrease of 'wanting' to eat.

Human eating behavior may be influenced non-homeostatically by the rewarding value of foods, i.e. 'liking' (pleasure/palatability) and 'wanting' (incentive motivation). The objectives of this study were to validate a computer test for assessment of rewarding value of food, and to assess how rewarding value of food is affected by eating a dessert-specific (chocolate mousse, CM) vs. dessert non-specific, neutral food item (cottage cheese, CC). Seventy-three subjects (47f/26m, age 27.8+/-10.0 y, BMI 24.1+/-3.3 kg/m(2)), studied in a randomized cross-over design, came to the university twice, fasted. A computer test was developed to determine rewarding value, i.e. 'liking' and 'wanting', for 72 items divided in six categories (bread, filling, drinks, dessert, sweets, stationery). 'Liking' was measured by indicating relative preference of paired items (within/between categories), 'wanting' by working to earn items to choose from. Subjects completed the computer test before and after consumption of CM/CC, matched for energy content (5.6 kJ/g) and daily energy requirements (10%). 'Liking' and 'wanting' scores of all fasted subjects on the two test-days showed 62-73% reproducibility. CM was liked more than CC (p<0.001). Consumption of CM decreased 'wanting' for bread, filling, drinks and dessert (p<0.03). Consumption of CC decreased 'wanting' for bread only (p<0.05). Contrary to CC, CM decreased relative 'liking' for the dessert category (p<0.001). In conclusion, the computer test for measurement of 'liking' and 'wanting' is sufficiently valid. Eating a highly liked food item induces a more distinct decrease in 'wanting' for food items in general and category-specific 'liking', than eating a sufficiently liked neutral food item.

Heat production and body temperature during cooling and rewarming in overweight and lean men.

OBJECTIVE: To compare overweight and lean subjects with respect to thermogenesis and physiological insulation in response to mild cold and rewarming. RESEARCH METHODS AND PROCEDURES: Ten overweight men (mean BMI, 29.2 +/- 2.8 kg/m(2)) and 10 lean men (mean BMI, 21.1 +/- 2.0 kg/m(2)) were exposed to cold air for 1 hour, followed by 1 hour of rewarming. Body composition was determined by hydrodensitometry and deuterium dilution. Heat production and body temperatures were measured continuously by indirect calorimetry and thermistors, respectively. Muscle activity was recorded using electromyography. RESULTS: In both groups, heat production increased significantly during cooling (lean, p = 0.004; overweight, p = 0.006). The increase was larger in the lean group compared with the overweight group (p = 0.04). During rewarming, heat production returned to baseline in the overweight group and stayed higher compared with baseline in the lean group (p = 0.003). The difference in heat production between rewarming and baseline was larger in the lean (p = 0.01) than in the overweight subjects. Weighted body temperature of both groups decreased during cold exposure (lean, p = 0.002; overweight, p < 0.001) and did not return to baseline during rewarming. DISCUSSION: Overweight subjects showed a blunted mild cold-induced thermogenesis. The insulative cold response was not different among the groups. The energy-efficient response of the overweight subjects can have consequences for energy balance in the long term. The results support the concept of a dynamic heat regulation model instead of temperature regulation around a fixed set point.

Energy balance at high altitude: 6542 / Balance de energía en la altura: 6542

La pérdida de peso debido a malnutrición y posiblemente a malabsorción intestinal es un fenómeno conocido en escaladores de montaña. Hasta 5000 m el balance de energía es mantenido debido a que la energía por la digestión intestinal permanece normal. Se han estudiado 10 sujetos (cuatro mujeres y seis varones, 27-44 años) durante una permanencia de 21 días en el pico del Monte Sajama, Bolivia (6542 m), para observar si la energía de la digestión juega un rol importante en el déficit de energía, ingesta de energía, gasto de energía, composición corporal, y energía de la digestión. La ingesta de energía se midió durante dos intervalos de 3 días: 7-9 (EI1) y 17-19 (EI2). La pérdida de energía fecal total durante EI1 fue calculada de la energía medida por un calorímetro de bomba. La tasa metabólica diaria promedio (ADMR) en la altura fue medida en seis sujetos, dos mujeres y cuatro varones, con agua marcada con deuterio sobre un intervalo de 10 días: 9-19. La tasa metabólica basal (BMR) fue medida antes y después de la expedición por análisis de gas respirado. La composición corporal fue estimada de los panículos adiposos y de la masa corporal antes y durante la estadía en la altura. Los sujetos estuvieron en balance energético negativo durante todo el período de observación. (EI1-ADMR es igual a -2.9 +/- 1.8 MJ/d y EI2-ADMR es igual a -2.3 +/- 1.8 MJ/d, basado en una gruesa energía de digestión de 95 por ciento). La pérdida de la masa grasa (3.7 +/- 1.5 Kg) representó 74 +/- 15 por ciento de la pérdida de la masa corporal. El contenido de energía de las heces fue 21 kJ/d de peso seco y la energía gruesa de la digestión llegó a 85por ciento. El déficit de energía aumentó a 3.5 Mj/d después de corregir la disminuída energía de la digestión. En conclusión el balance enregético no fue alcanzado a 6542 m. El déficit energético resultante parece ser el resultado de malnutrición y tan sólo una determinada parte puede ser atribuhído a malabsorción.