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Exposure to secondhand smoke (SHS) is a significant threat to public health, and represents a danger for both the development and health status of children and adolescents. Taking the above into account, our aim was to quantify Greek adolescents’ exposure to SHS using serum cotinine levels. During 2006, 341 adolescents aged 13-17 were randomly selected from high schools in Heraklion and agreed to participate as part of the European Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study. Blood samples were drawn from a random sample of 106 adolescents, while serum cotinine/nicotine concentrations were measured by Gas Chromatography—Mass Spectrometry (GC-MS). The mean levels of serum cotinine and nicotine were calculated at 1.60 ± 2.18 ng/mL and 4.48 ± 4.00 ng/mL, respectively, while 97.7% of the non-smoker adolescents were found to have measureable levels of serum cotinine indicating exposure to SHS. The analysis revealed that their paternal (p = .001) and maternal smoking habits (p = .018) as also the existence of a younger brother or sister (p = .008) were the main modifiers of SHS exposure during adolescence. Conclusively, almost all of the measured Greek adolescents were exposed to SHS, even when their parents were non-smokers. This finding indicates the need for both community and school-based educational programmes as also the implementation of a comprehensive ban on smoking in public places.

On September 29, 2011, acknowledged experts in the field of vitamin D, mainly European, were brought together in order to discuss the recent scientific advances in relation to vitamin D: the current requirements and associations with various health outcomes. In this article, the discussions resulting from the meeting are summarized. INTRODUCTION: Several groups at risk for developing vitamin D insufficiency have been identified. Accordingly, reviews indicate that a significant percentage of the population worldwide have serum 25-hydroxyvitamin D levels below 50 nmol/l. In addition to the role of vitamin D in bone health, recent studies suggest that it may play a pivotal role in other systems, e.g., the cardiovascular system, pancreas, muscle, immune system and brain. Most evidence, however, is obtained from observational studies and yet inconclusive. METHODS: To exchange and broaden knowledge on the requirements for vitamin D and its effect on various health outcomes, a workshop entitled "Vitamin D Expert Meeting: Do we get enough?", was organized. RESULTS: Despite low vitamin D levels worldwide, consensus on the definition of deficiency is not yet reached. In order to define cut-off points for vitamin D whilst taking into account extraskeletal health effects, randomized controlled trials in these fields are warranted. The experts do emphasize that there is evidence to suggest an important role for vitamin D in the maintenance of optimal bone health at all ages and that vitamin D supplementation, in most studies co-administered with calcium, reduces fracture risk in the senior population. CONCLUSION: To reach a serum 25-hydroxyvitamin D level of 50 nmol/l older adults aged >/=65 years are therefore recommended to meet a mean daily vitamin D intake of 20 mug (800 IU), which is best achieved with a supplement.

Optimal nutrition is an important prerequisite for a top-level performance in sports. Of primary importance in this connection is the bioavailability of carbohydrates and fats as a source of energy so that the muscles can produce ATP. The amount of glycogen in the liver and skeletal muscles and possibly the intramuscular triglyceride levels play a pivotal role in this process. Gradually decreasing the amount of training during the last 6-7 days before an important game and simultaneously increasing the amount of dietary carbohydrates results in a higher physical performance. Studies have shown that carbohydrate-electrolyte solutions with 6-8% carbohydrate by weight and an osmolarity of 250-350 mosmol/l result in a maximal carbohydrate oxidation from the solution of about 1.0-1.1 g/min and a significantly enhanced endurance. A combination of carbohydrates and proteins or amino acids has proven to be very effective to accelerate recovery after exhausting exercise. Functional food ingredients such as caffeine and creatine result in a significantly enhanced performance. This is contrast to many other ingredients and products for which the extravagant claims have not been substantiated. Hence, in addition to a few functional sports supplements for which the value has been scientifically demonstrated, sound nutrition remains an absolute prerequisite for an optimal performance in sports.

The aim of this study was to elucidate the roles of the beta(1)- and the beta(2)-adrenoceptors in thermogenesis and lipid utilization in obesity. The beta(1)-adrenoceptor study was performed in 9 obese and 10 lean men and consisted of 4 30-min periods during which subjects received consecutive infusions of 0, 3, 6, and 9 microg/kg fat-free mass (FFM).min dobutamine. Energy expenditure, lipid oxidation, and plasma nonesterified fatty acids and glycerol concentrations increased similarly in both groups during beta(1)-adrenergic stimulation. The beta(2)-adrenoceptor study was performed in 10 obese and 11 lean men and involved 3 45-min periods during which 0, 50, and 100 ng/kg FFM.min salbutamol were given in combination 1.2 microg/kg FFM.min atenolol (bolus, 50 microg/kg FFM). During beta(2)-adrenergic stimulation, the increases in energy expenditure and plasma nonesterified fatty acids and glycerol concentrations were reduced in the obese group. Furthermore, lipid oxidation significantly increased in the normal weight group, but remained similar in the overweight group. In conclusion, these data suggest that beta(1)-adrenoceptor-mediated metabolic processes are similar in both groups, but beta(2)-adrenoceptor-mediated increases in thermogenesis and lipid utilization are impaired in the obese.

In a previous study the oxidation of plasma free fatty acids (FFA) under baseline conditions and during exercise was lower in type 2 diabetic subjects compared with weight-matched controls. The present study intended to investigate the effect of weight reduction (very low calorie diet) on plasma FFA oxidation in seven type 2 diabetic male subjects (body fat, 37.4 +/- 1.2%; age, 51.3 +/- 3.4 yr; plasma glucose, 7.45 +/- 0.48 mmol/L). Subjects underwent a 10-week diet period. Body composition and substrate utilization during rest and during bicycle exercise (50% of maximum aerobic capacity) were determined before and after the diet (during weight-stable conditions). FFA metabolism was studied by means of the tracer [U-(13)C]palmitate. Rates of oxidation of plasma FFA were corrected with an acetate recovery factor. Additionally, activities of mitochondrial enzymes and cytosolic fatty acid-binding protein were determined in biopsies from the vastus lateralis muscle before and after the diet. The very low calorie diet resulted in a weight loss of 15.3 kg (110.8 +/- 7.4 vs. 95.5 +/- 5.8 kg; P0.01). The basal rates of appearance and disappearance of FFA decreased as a result of diet. The rates of appearance and disappearance of FFA during exercise were not different before and after diet. The oxidation of plasma-derived fatty acids tended to decrease after diet during baseline conditions (P = 0.10), whereas the plasma FFA oxidation during exercise was not different before and after the diet (14.1 +/- 1.9 vs. 14.8 +/- 1.8 micromol/kg fat-free mass.min). Skeletal muscle cytosolic fatty acid-binding protein and the activities of muscle oxidative enzymes did not significantly change as a result of weight loss. In conclusion, considerable weight reduction did not significantly improve plasma-derived FFA oxidation under baseline conditions and during exercise, suggesting that this impairment reflects a primary defect leading to the development of type 2 diabetes mellitus rather than resulting from the type 2 diabetic state.

Sibutramine is a tertiary amine that has been shown to induce dose-dependent weight loss and to enhance the effects of a low-calorie diet for up to a year. We did a randomised, double-blind trial to assess the usefulness of sibutramine in maintaining substantial weight loss over 2 years.Eight European centres recruited 605 obese patients (body-mass index 30-45 kg/m2) for a 6-month period of weight loss with sibutramine (10 mg/day) and an individualised 600 kcal/day deficit programme based on measured resting metabolic rates. 467 (77%) patients with more than 5% weight loss were then randomly assigned 10 mg/day sibutramine (n=352) or placebo (n=115) for a further 18 months. Sibutramine was increased up to 20 mg/day if weight regain occurred. The primary outcome measure was the number of patients at year 2 maintaining at least 80% of the weight lost between baseline and month 6. Secondary outcomes included changes in uric acid concentrations and glycaemic and lipid variables. Analysis was by intention to treat.148 (42%) individuals in the sibutramine group and 58 (50%) in the placebo group dropped out. Of the 204 sibutramine-treated individuals who completed the trial, 89 (43%) maintained 80% or more of their original weight loss, compared with nine (16%) of the 57 individuals in the placebo group (odds ratio 4.64, p0.001). Patients had substantial decreases over the first 6 months with respect to triglycerides, VLDL cholesterol, insulin, C peptide, and uric acid; these changes were sustained in the sibutramine group but not the placebo group. HDL cholesterol concentrations rose substantially in the second year: overall increases were 20.7% (sibutramine) and 11.7% (placebo, p0.001). 20 (3%) patients were withdrawn because of increases in blood pressure; in the sibutramine group, systolic blood pressure rose from baseline to 2 years by 0.1 mm Hg (SD 12.9), diastolic blood pressure by 2.3 mm Hg (9.4), and pulse rate by 4.1 beats/min (11.9).This individualised management programme achieved weight loss in 77% of obese patients and sustained weight loss in most patients continuing therapy for 2 years. Changes in concentrations of HDL cholesterol, VLDL cholesterol, and triglyceride, but not LDL cholesterol, exceed those expected either from weight loss alone or when induced by other selective therapies for low concentrations of HDL cholesterol relating to coronary heart disease.

To investigate the long-term effects of changes in dietary carbohydrate/fat ratio and simple vs complex carbohydrates.Randomized controlled multicentre trial (CARMEN), in which subjects were allocated for 6 months either to a seasonal control group (no intervention) or to one of three experimental groups: a control diet group (dietary intervention typical of the average national intake); a low-fat high simple carbohydrate group; or a low-fat high complex carbohydrate group.Three hundred and ninety eight moderately obese adults.The change in body weight was the primary outcome; changes in body composition and blood lipids were secondary outcomes.Body weight loss in the low-fat high simple carbohydrate and low-fat high complex carbohydrate groups was 0.9 kg (P0.05) and 1.8 kg (P0.001), while the control diet and seasonal control groups gained weight (0.8 and 0.1 kg, NS). Fat mass changed by -1.3kg (P0.01), -1.8kg (P0.001) and +0.6kg (NS) in the low-fat high simple carbohydrate, low-fat high complex carbohydrate and control diet groups, respectively. Changes in blood lipids did not differ significantly between the dietary treatment groups.Our findings suggest that reduction of fat intake results in a modest but significant reduction in body weight and body fatness. The concomitant increase in either simple or complex carbohydrates did not indicate significant differences in weight change. No adverse effects on blood lipids were observed. These findings underline the importance of this dietary change and its potential impact on the public health implications of obesity.

In a study of the impact of aspartame, fat, and carbohydrate on appetite, we monitored blood glucose continuously for 431 (SE 16) min. Ten healthy males (19-31 years) participated in three time-blinded visits. As blood glucose was monitored, appetite ratings were scored at randomized times. On the first meal initiation, volunteers consumed one of three isovolumetric drinks (aspartame, 1 MJ simple carbohydrate, and 1 MJ high-fat; randomized order). High-fat and high-carbohydrate foods were available ad libitum subsequently. Blood glucose patterns following the carbohydrate drink (+1.78 (SE 0.28) mmol/l in 38 (SE 3) min) and high-fat drink (+0.83 (SE 0.28) mmol/l in 49 (SE 6) min) were predictive of the next intermeal interval (R 0.64 and R 0.97 respectively). Aspartame ingestion was followed by blood glucose declines (40% of subjects), increases (20%), or stability (40%). These patterns were related to the volunteers' perception of sweetness of the drink (R 0.81, P = 0.014), and were predictive of subsequent intakes (R -0.71, P = 0.048). For all drinks combined, declines in blood glucose and meal initiation were significantly associated (chi 2 16.8, P0.001), the duration of blood glucose responses and intermeal intervals correlated significantly (R 0.715, P = 0.0001), and sweetness perception correlated negatively with hunger suppression (R -0.471, P = 0.015). Effects of fat, carbohydrate, and aspartame on meal initiation, meal size, and intermeal interval relate to blood glucose patterns. Varied blood glucose responses after aspartame support the controversy over its effects, and may relate to sweetness perception.

The aim of the present study was to establish whether gastro-intestinal (GI) complaints observed during and after ultra-endurance exercise are related to gut ischaemia-associated leakage of endotoxins [lipopolysaccharide (LPS)] into the circulation and associated cytokine production. Therefore we collected blood samples from 29 athletes before, immediately after, and 1, 2 and 16 h after a long-distance triathlon for measurement of LPS, tumour necrosis factor-alpha and interleukin-6 (IL-6). As the cytokine response would trigger an acute-phase response, characteristic variables of these responses were also measured, along with creatine kinase (CK) to obtain an indicator of muscle damage. There was a high incidence (93% of all participants) of GI symptoms; 45% reported severe complaints and 7% of the participants abandoned the race because of severe GI distress. Mild endotoxaemia (5-15 pg/ml) was evident in 68% of the athletes immediately after the race, as also indicated by a reduction in IgG anti-LPS levels. In addition, we observed production of IL-6 (27-fold increase immediately after the race), leading to an acute-phase response (20-fold increase in C-reactive protein and 12% decrease in pre-albumin 16 h after the race). The extent of endotoxaemia was not correlated with the GI complaints or the IL-6 response, but did show a correlation with the elevation in C-reactive protein (r(s) 0.389; P=0.037). Creatine kinase levels were increased significantly immediately post-race, and increased further in the follow-up period. Creatine kinase levels did not correlate with those of either IL-6 or C-reactive protein. It is therefore concluded that LPS does enter the circulation after ultra-endurance exercise and may, together with muscle damage, be responsible for the increased cytokine response and hence GI complaints in these athletes.

Skeletal muscle has the ability to adapt as result of dietary, hormonal or pharmacological interventions affecting energy metabolism. The aim of the present study was to investigate the effects of energy restriction on skeletal muscle metabolic characteristics in obese women.The effects of 8 weeks' energy restriction on body composition, energy expenditure and skeletal muscle characteristics were investigated in 28 healthy obese women. Subjects were aged 37.9 +/- 1.5 years and had a body mass index of 32.0 +/- 0.8 kg m-2.Energy restriction (2800 kJ day-1) resulted in a 10.8 +/- 0.5 kg weight loss consisting of 8. 6 +/- 0.5 kg of fat mass and 2.2 +/- 0.3 kg of fat-free mass. Basal respiratory exchange ratio, sleeping metabolic rate and exercise-induced thermogenesis significantly declined in response to the diet. These changes were accompanied by an increase (P = 0.038) in the skeletal muscle content of cytosolic fatty acid-binding protein (H-FABP), whereas no changes occurred in fibre type distribution or activities of enzymes reflecting beta-oxidation and mitochondrial density (3-hydroxyacyl-CoA dehydrogenase and citrate synthase respectively).The results suggest that increased capacity of intracellular fatty acid transport in skeletal muscle cells is involved in the physiological adaptations of fat metabolism to energy restriction in obese female subjects.

If short term weight loss is the main treatment objective, it is clear that exercise does not give any success. Dietary restriction can potentially induce much faster rates of weight loss. Adding exercise and especially weight training, to a diet-induced weight loss programme induces small improvements in the change in FFM/FM and possible RMR after a relatively long period. Exercise treatment alone is an option for longterm treatment with relatively small changes in body weight and body composition. Especially in obese subjects energy intake and expenditure compensation does not occur. Although it is not the scope of this review exercise seems to be the ideal option for successful maintenance of a reduced body weight.

Intensive exercise affects digestion and absorption. Nevertheless, athletes involved in intensive endurance exercise are advised to ingest fluid and energy supplying nutrients, to compensate for the losses and to delay fatigue. The present review describes the effects of exercise on the gastrointestinal tract and the aspects which determine optimal fluid and nutrient delivery during exercise in different climatological and exercise conditions.

Resting energy expenditure (REE) was determined in 30 patients with newly detected non-small cell lung cancer. Measured values were compared with the values predicted by the Harris-Benedict (HB) formula. Mean REE was 20% higher than predicted. Sixty percent of the patients (18 patients) had an elevated REE (greater than or equal to 115%) compared with this formula. The prevalence of hypermetabolism in a group of patients with gastric and colorectal cancer was only 13% (13 of 104 patients). When corrected for fat-free mass (FFM), REE was still significantly higher (P less than 0.001) in the lung cancer group compared with the gastric and colorectal cancer group. Whereas weight loss in healthy men leads to an adaptational decrease in energy expenditure (EE), weight loss in the patients with lung cancer was accompanied by an increase in REE. Tumor stage, tumor localization, pulmonary function, or smoking behavior could not explain the observed increase in REE in patients with lung cancer. Therefore, these metabolic alterations appear to be tumor mediated.

The purpose of this study was to establish the intra-individual variation in the rate of gastric emptying (GE) by using the double sampling technique of George. Eight healthy male volunteers, all familiar with gastric intubation and testing, participated in four GE tests, using an isotonic fluid as a test meal. Conditions were kept constant during all four tests, and each test was separated by at least 48 h. The within-subjects coefficient of variation proved to be 29%. The findings demonstrate that, given standard conditions, GE is reproducible from day to day.

Weight loss after gastric partition is highly variable even when the operation itself has been successful. We studied changes in body composition in relation to energy expenditure before and one year after surgery in one woman and five men, age 20-38 years, and BMI 42-62 kg/m2. Observations were performed shortly before, and 6, 12, 27 and 54 weeks after surgery. Body composition was measured with hydrostatic weighing and isotope dilution, and energy expenditure over 24 h (24EE) and during complete rest (sleeping metabolic rate (SMR)) with a respiration chamber and in five of the six subjects under daily living conditions over two-week intervals with doubly labeled water (average daily metabolic rate (ADMR). Weight loss and fat loss over the full observation period until 54 weeks after surgery was 54 +/- 8 and 43 +/- 9 kg (mean +/- s.e.m.), respectively. There was a more than three-fold difference in fat loss between the subject losing most, i.e. 70 kg, and the subject losing least, i.e. 20 kg. Fat loss was not related to initial fat mass in this group of six subjects but there was a significant negative relation with the loss of protein mass. There was a strong negative relation between fat loss and activity level of the subjects expressed as the quotient ADMR/SMR. These results show the contrary from what would be expected. Reduction of fat mass after successful gastric partition is highest in those subjects having the lowest physical activity level (before and) after surgery; these subjects lose less fat-free mass.

In the present investigation we determined metabolic rate during sleep (SMR) as a function of physical activity (PA) in normal daily life. Subjects were nine females and six males, with an average age of 30 yr (range 19-48) and an average Quetelet Index of 32 (range 14-62). The level of SMR was expressed as an index; SMI = SMR/BMR, where SMR was measured in a respiration chamber while subjects were asleep and basal metabolic rate (BMR) was calculated with the equation from Harris and Benedict. Physical activity, calculated from average daily metabolic rate (ADMR) and BMR, was expressed as an index: PAI = ADMR/BMR, where ADMR was measured with doubly labeled water and BMR was calculated as indicated above. Individual values of SMI were 0.8-1.2. SMI was positively correlated with PAI (r = 0.85, P less than 0.001). Subjects with either a high or a low Quetelet Index were concentrated in the lower range of PAI compared with normal-weight subjects. In conclusion, subjects with an extremely low or high body weight generally show a lower than expected SMR associated with a low physical activity.

An estimate of a patient's energy needs is usually derived from equations, which predict energy expenditure (EE) by considering sex, age and body weight. Due to the increasing number of elderly people in a hospital population, more data on energy requirements in this age-group are needed. In this study resting energy expenditure (REE) of 40 healthy men and women, aged 51-82 years, was measured using a ventilated hood system. The results showed that some commonly used prediction equations underestimated REE by approximately 6 per cent. REE was highly correlated with fat free mass (FFM) (r = 0.88; P less than 0.001) and body weight (r = 0.85; P less than 0.001). A stepwise multiple regression analysis showed that the combination of body weight, sex and age resulted in the best prediction for REE; REE (kcal) = 1641 + 10.7 weight (kg)--9.0 age (years)--203 sex (1 = male, 2 = female) (r = 0.92). However, REE of an individual may be over- or underestimated by +/- 225 kcal (10-20 per cent) due to large between-subject variations. We suggest therefore that the energy requirements of elderly people should be measured rather than predicted. Due to small within-subject variations (including measurement error) a single REE measurement would suffice. Sleeping energy expenditure (SEE) was 7 per cent lower than REE.

Measurement of body composition is important in the assessment of nutritional status in cancer patients. The purpose of this study was to validate the bioelectrical impedance (BI) method for body composition estimation in 33 elderly cancer patients (mean age 66 +/- 9 years) using the deuterium dilution technique (2H2O) as the reference method. Height2/Resistance (H2/R) correlated significantly with total body water (TBW) computed from 2H2O (r = 0.89, P less than 0.001; s.e.e. = 2.4 l). The prediction equation for TBW improved significantly (P less than 0.001) by addition of H2/R to the predictor variables weight, height, age and sex. We conclude that BI is a useful measure for the assessment of body composition in cancer patients.

In the present study 44 participants (32 females and 12 males) of the studies on the effects of a diet (D) diet-exercise (DE) treatment on body composition and sleeping metabolic rate (SMR), were followed over a period of 18, 36 or 42 months post-treatment. Mean weight loss after treatment (12-14 weeks) was 12.0 and 16.5 kg for D and DE respectively (P less than 0.05; D. v. DE) and fat loss (9.5 kg and 13.5 kg for D and DE respectively, D v. DE P less than 0.05). Nine subjects dropped out during the follow-up phase. After 18, 36 or 42 months follow-up the diet group regained 90% of their initial weight loss compared to 60% of the diet-exercise group (P less than 0.05). Seven subjects out of the original diet-exercise group kept up their exercise activities, while two subjects from the diet group started exercising. These subjects (EX) gained only 23 per cent of their weight loss, but their body weight at the start of the study tended to be lower compared to the diet and the diet-exercise group (86.5 (EX) v. 91.4 and 95.2 for D and DE respectively). During the last follow-up measurement SMR of 18 subjects was determined and revealed a persistent lower SMR for nine non-exercising subjects (18.6 per cent lower than before treatment), whereas for subjects who kept on exercising, SMR was 9.8 per cent lower than baseline values. Per kg FFM SMR was almost restored to baseline values for the EX group, whereas the non-exercising subjects still showed depressed values (EX 3.7 per cent and D + DE 15.8 per cent lower than before treatment; P less than 0.05). It was concluded that exercise is one of the factors which contributes to the restoration of SMR and long term weight maintenance.

The micronutrient status of 12 obese male subjects was evaluated before and after a 14-week period of a low energy diet (3.0-3.9 MJ) with or without an exercise (5 h p/w) treatment. The subjects were matched on the basis of their body mass index (BMI kg/m2) into a diet group (D; average BMI 32.2) and a diet-exercise group (DE; average BMI 32.9). After 14 weeks both groups showed similar results in term of weight loss (D 15.1; DE 16.4 kg), fat loss (D 11.7; DE 13.6 kg) and loss of fat free mass (FFM) (D 3.4; DE 2.8 kg). With respect to changes of the micronutrients in blood plasma only the decrease in ferritin was significantly different between D and DE (P less than 0.05), with a larger decrease for DE. In both groups significant decreases of about 20% in fat soluble vitamins were observed. Water soluble vitamins demonstrated a large variation between individuals and decreases were not significant.

A compact, rugged, solid-state heart rate recorder (63 X 94 X 22 mm, 195 g) to measure normal daily heart rates over periods of up to 33 h is described. With an interval switch a selection can be a mean heart rate over 30, 60 or 120 sec. The ECG amplifier filter is equipped with an automatic gain control to eliminate R-wave amplitude changes during physical activity. A continuous acoustic check on correct electrode attachment and sufficient signal amplitude is possible by means of an earphone. Data may be stored on punch tape, tape recorder, or processed on-line, or plotted directly one a line writer to obtain a heart rate profile over the measured time. In 45 studies with adults and children the heart rate recorder has proven to be a reliable instrument.

Carbohydrate containing drinks are commonly consumed as an ergogenic aid during endurance sports activities. The efficacy of a given drink is limited by the rate of absorption, which is in turn limited by gastric emptying. A myriad of factors influence gastric emptying. The influence of several of these factors (training status, exercise intensity, and carbohydrate composition) was investigated by repeated experiments using a nasogastric tube and a modification of the technique of George. A group of well-trained bicyclists and a group of untrained subjects performed similar experiments. Three different carbohydrate containing drinks (15 g.100 ml-1 glucose (G), 15 g.100 ml-1 maltodextrin plus 3 g.100 ml-1 fructose (MD), 7 g.100 ml-1 sucrose (I] and artificially sweetened water were compared during rest and 50 and 70% Wmax bicycling. Experimental design was crossover. There was a trend for the carbohydrate drinks to empty initially more slowly under the influence of exercise. Differences in drink volume remaining in the stomach were significant (P less than 0.05), with I at 10 min (70%, mean = 48.9%; rest, mean = 30.5%) and at 20 min (70%, mean = 28.9%; rest, mean = 23.8%) and with MD at 10 min (70%, mean = 71.1%; rest, mean = 55.9%). A similar trend was also seen with 50% Wmax exercise; however, this trend was only significant with MD at 10 min (50%, mean = 72.1%; rest, mean = 55.9%). Drink composition was a much stronger inhibitor of gastric emptying. However, all drinks emptied exponentially with fast-phase initial emptying rates. No differences in gastric emptying or secretion were observed between trained and untrained subjects.

Information about habitual food intake was systematically obtained from elite endurance, strength, and team sport athletes. The athletes (n = 419) trained at least 1-2 h daily and competed on an international level. A 4- or 7-day food diary was kept. For analysis of the data, a computerized food table was used. Mean energy intake varied from 12.1-24.7 MJ per day for male and 6.8-12.9 MJ per day for female athletes. Protein intake was in agreement with or higher than the Dutch recommendations. Contribution of carbohydrate intake to total energy intake varied from 40%-63%. Fat intake tended to meet the criteria for a prudent diet (less than 35%). Snacks contributed about 35% to the total energy intake and the bread/cereals and dairy food groups were the most important energy sources. It is concluded that in general there are two major concerns. In those sports in which body composition plays an important role, energy and thus nutrient intake is often marginal. In all groups of athletes intake of carbohydrate is insufficient.

Sustained exhausting exercise is thought to depress appetite and food intake. The aim of the present investigation was to study the effect of intensive cycling exercise, with an energy expenditure comparable to values derived from the Tour de France, on food and fluid intake, energy balance, nitrogen balance, and nutrient oxidation. Thirteen highly trained cyclists consuming a normal carbohydrate (CHO)-rich diet (60 En%) were studied during a 7-day stay in a respiration chamber. Two preparation days were followed by a standardized resting day (3), after which the subjects completed two exhausting exercise days (4-5). On day 6 the standardized resting day was repeated. Food and fluid intake were measured by weighed procedure. Energy expenditure was calculated from continuous gas analysis. Energy and nitrogen losses were calculated from all measured excretes. The results showed that energy balance (EB) and nitrogen balance (NB) were positive on the first resting day and became negative on the exercise days. EB was positive again on the recovery day whereas NB remained negative. Nitrogen losses almost balanced N intakes (1.7 g.kg-1) indicating an increased protein requirement. CHO oxidation exceeded CHO intake indicating endogenous CHO depletion. Contribution of CHO to energy exchange decreased from 51.4% +/- 3.1% on day 4 to 40.6% +/- 3.4% on day 5; this decrease was compensated by an increased fat oxidation. The food consumption pattern during days 4 and 5 was not different from days 2 and 6. In-between meal consumption accounted for 30.5%-34.3% of total energy intake. Fluid consumption was adequate to compensate for the losses.(ABSTRACT TRUNCATED AT 250 WORDS)

Body composition, sleeping metabolic rate (SMR), 24-h energy expenditure (24-EE) and daily physical activity were determined in 12 obese women during and after 12 weeks of exercise (4 h per week on 55 per cent of VO2 max) and/or energy restriction (2.9-3.5 MJ/d). Diet(D) and diet-exercise (DE) groups were formed by matching the subjects on their body mass index (BMI, kg/m2; mean 30.3). After 12 weeks no significant differences were shown in loss of weight (D 12.2 and DE 13.2 kg) and loss of fat mass (D 9.4 and DE 10.9 kg). Both groups reduced their SMR (D 29.9 per cent and DE 21.7 per cent) and their metabolic rate during the entire night measured by indirect calorimetry (12-EE) (D 36.4 per cent and DE 28.6 per cent; P less than 0.05). Energy expenditure over 24 h, estimated by means of heart-rate monitoring, was reduced by 22.1 per cent for D and by 19.6 per cent for DE (n.s.). Daily physical activity, which was determined during 5 d using an actometer, was increased after 12 weeks for DE (27 per cent; P less than 0.05) and D (10 per cent; n.s.). The suggestion that a reduction in normal activities of daily life in a diet-exercise group is the explanation for the absence of significant differences in weight and fat loss between a diet-exercise and a diet group is not confirmed in this study. Daily physical activity showed a significantly higher increase for the diet-exercise group than for the diet group, while the decline of SMR and 24-EE tended to be smaller.

In the Tour de France competing cyclists must pedal about 4000 km over a period of three weeks with only one day allowed for rest. The course includes 30 mountains, the highest of which reaches an altitude of approximately 2700 m. The energy expenditure values of these cyclists range from a mean of 25.4 MJ/day to peak values of 32.7 MJ/day. These are the highest values that have ever been reported for a period longer than seven days. On the basis of the food records of 5 cyclists, it turned out that 62 En.% is derived from CHO, 15 En.% from protein, and 23 En.% from fat. Since the food choice is primarily focused on digestibility and energy content, this results in a frequent consumption of sweet cakes and CHO-rich fluids. Some 49% of the energy is consumed in between meals. Such a nutritional pattern leads to a lowering of the nutrient density especially with respect to the B-vitamins. Intake of vitamins B1, B2, B6, and C, including contribution from enriched sport drinks, was 1.97 mg, 4.96 mg, 2.40 mg, and 158 mg, respectively. Besides this, intramuscular injections of megadosis vitamins of B1, B2, B6, nicotinamide, pantothenic acid, and especially B12 did increase the intake drastically. This was reflected in high blood concentrations of vitamins. Except for folic acid, vitamins (B1, B2, B6, and B12) exceeded the upper limits of the values from a reference group, particularly B12, which exceeded the reference values by up to 400%. During the Tour, vitamin concentrations remained essentially unchanged.

In a group of 4- to 6-year-old children and a group of 8- to 12-year-old children physical performance capacity, daily physical activity, body composition, blood lipids and daily food intake were determined. Children with a high performance capacity (W170) are more active during the day and do eat more. In the 8- to 12-year-old group it turns out that these extra calories are derived from unfavorable foodstuffs. There are no differences in blood lipids between any of the groups or subgroups. In the 8- to 12-year-old group, children with a low W170 are fatter than those with a high W170. In the younger age group this was not found.