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Objectives: This study aimed to identify factors related to changes in walking performance in individuals 3 months after a stroke or TIA. Design: Cross-sectional study with post hoc analysis of a randomised controlled study. Setting: University Hospital, Sweden. Participants 79 individuals, 64 (10) years, 37% women, who were acutely hospitalised because of stroke or TIA between November 2016 and December 2018. Inclusion criteria were patients aged 18 or above and the major eligibility criterion was the ability to perform the 6 min walking test. Intervention: The intervention group received standard care plus daily mobile phone text messages (short message service) with instructions to perform regular outdoor walking and functional leg exercises in combination with step counting and training diaries. The control group received standard care. Outcome measures Multivariate analysis was performed and age, sex, group allocation, comorbidity, baseline 6 min walk test, body mass index (BMI), cognition and chair-stand tests were entered as possible determinants for changes in the 6 min walk test. Results: Multiple regression analyses showed that age (standardised beta -0.33, 95% CI -3.8 to -1.05, p<0.001), sex (-0.24, 95% CI -66.9 to -8.0, p=0.014), no comorbidity (-0.16, 95% CI -55.5 to 5.4, p=0.11), baseline BMI (-0.29, 95% CI -8.1 to -1.6, p=0.004), baseline 6 min walk test (-0.55, 95% CI -0.5 to -0.3, p<0.001) were associated with changes in 6 min walk test 3 months after the stroke event. The regression model described 36% of the variance in changes in the 6 min walk test. Conclusions: Post hoc regression analyses indicated that younger age, male sex, lower BMI and shorter 6 min walk test at baseline and possible no comorbidity contributed to improvement in walking performance at 3 months in patients with a recent stroke or TIA. These factors may be important when planning secondary prevention actions.

Objective The aim of this study was to evaluate the effect of a novel, oral, modified-release formulation of the lipase inhibitor orlistat and the glucosidase/amylase inhibitor acarbose (denoted EMP16) on relative body weight after 26 weeks compared with placebo. Methods The randomized, double-blind, placebo-controlled trial had a 26-week treatment period, with dose escalation up to 6 weeks. Participants, adults between ages 18 and 75 years, with BMI >= 30 kg/m(2) or >= 28 kg/m(2) with risk factors, were randomly assigned to EMP16 120-mg orlistat/40-mg acarbose (EMP16-120/40), EMP16-150/50, or placebo. The primary end point was relative weight loss from baseline to week 26 assessed in participants with at least one post-baseline weight measurement. Results Of 156 randomized participants, 149 constituted the intention-to-treat population. The mean (95% CI) estimated treatment difference to placebo in relative weight loss after 26 weeks in the intention-to-treat population was -4.70% (-6.16% to -3.24%; p < 0.0001) with EMP16-120/40 and -5.42% (-6.60% to -4.24%; p < 0.0001) with EMP16-150/50. Conclusions This trial indicates that orlistat and acarbose can be successfully combined in a modified-release formulation to provide efficacious weight loss with no unexpected safety issues. EMP16 may be a promising candidate among other medications for improved weight management.

OBJECTIVE: To evaluate whetherdaily mobile-phone delivered messages with training instructions during three months increase physical activity and overall mobility in patients soon after stroke or transient ischemic attack. DESIGN: Randomised controlled trial with intention-to-treat analyses. SETTING: University hospital. Data collection from November 2016 until December2018. SUBJECTS: Seventy-nine patients (mean (SD) age 63.9 (10.4) years, 29 were women) were allocated to either intervention (n = 40) or control group (n = 39). Participants had to be independent (modified Ranking Scale ⩽2) and able to perform the six-minute walking test at discharge from the hospital. INTERVENTIONS: The intervention group received standard care and daily mobile phone instructional text messages to perform regular outdoor walking and functional leg exercises. The control group received standard care; that is, primary care follow-up. MAIN MEASURES: Walking performance by six-minute walking test (m), lower body strength by five times chair-stand test (s), the short physical performance battery (0-12 points) and 10-metres walk test (m/s) were assessed at baseline and after three months. RESULTS: The estimated median difference in the six-minute walking test was in favour of the intervention group by 30 metres (95% CI, 55 to 1; effect size 0.64; P = 0.037) and in the chair-stand test by 0.88 seconds (95% CI, 0.02 to 1.72; effect size 0.64; P = 0.034). There were no differences between groups on the short physical performance battery or in 10-metres walking time. CONCLUSIONS: Three months of daily mobile phone text messages with guided training instructions improved composite mobility measures; that is, walking performanceand lower body strength. CLINICAL TRIAL REGISTRY: The study is registered with ClinicalTrials.gov, number NCT02902367.

The safety of a novel modified-release oral capsule with orlistat and acarbose (MR-OA) was investigated in 67 obese middle-aged White men with a body mass index of 32 to 40 kg/m2 or 30 to 32 kg/m2 plus waist circumference >102 cm. The purpose of this investigation was to compare MR-OA with the existing conventional orlistat regarding systemic safety defined as plasma orlistat concentration at the end of the treatment period of 14 days. Participants took the MR-OA fixed-dose combination formulation 3 times a day together with a major meal. Three different doses of MR-OA were evaluated-60/20, 90/30, and 120/40 (mg orlistat/mg acarbose)-as well as 1 reference group who received the conventional orlistat, Xenical, with 120 mg of orlistat. Blood plasma was sampled on days 1 and 14. The orlistat plasma concentrations of the MR-OA dose showed a delayed absorption and were lower compared with conventional orlistat at the end of the study. All doses were safe and well tolerated without any unexpected adverse events and no serious adverse events. The delay in the rise of orlistat plasma concentration indicates that the modified-release properties of the MR-OA formulation are effective. The systemic exposure of orlistat resulting from MR-OA was similar, albeit a bit lower than the conventional orlistat with 120 mg of orlistat. We can therefore assume that the safety profile regarding the orlistat moiety of MR-OA is comparable to the conventional orlistat and a promising approach for weight control in obese patients. Further clinical evaluation is underway.

Objectives To evaluate effects of mobile phone text-messaging exercise instructions on body composition, cardiometabolic risk markers and self-reported health at 3 months after stroke. Design Randomised controlled intervention study with per-protocol analyses. Setting University Hospital in Sweden. Participants Seventy-nine patients (mean (SD) age 64 (10) years, 37% female) >= 18 years with good motor function (modified Rankin Scale <= 2) and capable to perform 6 min walking test at hospital discharge were randomised to either intervention (n=40) or control group (n=39). Key exclusion criteria: subarachnoid bleeding, uncontrolled hypertension, severe psychiatric problems or cognitive limitations. Interventions The intervention group received beyond standard care, daily mobile phone instructional text messages to perform regular outdoor walking and functional leg exercises. The control group received standard care. Main outcome measures Fat mass and fat-free mass were estimated by bioelectric impedance analysis. Cardiometabolic risk factors like blood lipids, glycated haemoglobin and blood glucose were analysed at baseline and after 3 months. Results Both groups changed favourably in fat-free mass (1.83 kg, 95% CI 0.77 to 2.89; p=0.01, effect size (ES)=0.63 vs 1.22 kg, 95% CI 0.39 to 2.0; p=0.05, ES=0.54) and fat mass (-1.30 kg, 95% CI -2.45 to -0.14; p=0.029, ES=0.41 vs -0.76 kg, 95% CI -1.74 to 0.22; p=0.123, ES=0.28). Also, many cholesterol related biomarkers improved; for example, total cholesterol -0.65 mmol/L, 95% CI -1.10 to -0.2; p=0.06, ES: 0.5 vs -1.1 mmol/L, 95% CI -1.47 to -0.56; p>0.001, ES=0.8. However, there were no between-group differences. At 3 months, 94% and 86%, respectively, reported very good/fairly good health in the text messaging and control groups. Conclusions No clear effect of 3 months daily mobile phone delivered training instructions was detected on body composition, cardiovascular biochemical risk factors or self-perceived hea

Objective There is an unmet medical need for a safe and effective weight loss product with minimal systemic side-effects. In this study, the effect of a novel modified-release fixed-dose combination of orlistat and acarbose (MR-OA) was compared with conventional orlistat (CO) regarding tolerability, appetite and glucose metabolism. Methods Sixty-seven men with obesity, aged 24 to 60 years with body mass indexes (BMIs) 33 to 40 kg m(-2) or BMIs 30 to 32 kg m(-2) and waist circumference above 102 cm were included. They were randomized to either three different doses of the test formulation MR-OA (60 mg orlistat/20 mg acarbose, 90/30 and 120/40) or CO (Xenical, 120 mg orlistat) for a 2-week study of daily treatment. The participants spent days 1 and 14 at the clinical research centre where they received standardized meals, had blood sampling and filled in questionnaires regarding tolerability and appetite after meals. In days 2 to 13, the participants were at home and continued to fill in the questionnaires daily. Results In the MR-OA groups, reports of liquid and oily stools as well as faecal incontinence were fewer, whereas reports of gastric distension and flatulence were higher, compared with the CO group. More participants reported decreased hunger in the 90/30 and 120/40 MR-OA, and postprandial plasma glucose concentration was reduced in all MR-OA groups compared with CO. Conclusions This study shows that by using a modified-release dosage form, orlistat and acarbose can be combined without compromising tolerability. Furthermore, MR-OA shows promising effects regarding reduction of appetite and reduces postprandial glucose. Tolerability is coupled to compliance and thereby efficacy of a treatment; therefore, this novel combination MR-OA could be an effective approach for weight loss treatment. A follow-up study in a more diverse population and for a longer duration with weight loss as primary outcome variable is planned.

AIM: To investigate if occurrence of newly diagnosed exercise induced bronchoconstriction (EIB) would affect adolescents' ability to assess their physical activity. METHODS: 99 selected adolescents with and 47 adolescents without self-reported exercise induced dyspnea were included. All of the 146 adolescents then performed a standardized exercise challenge test on a treadmill with dry-air inhalation to detect EIB. Free living physical activity was assessed during seven days with both accelerometer (objective assessment) and a validated activity diary (subjective assessment). Height, weight and subjective sleep were recorded. RESULTS: Out of the 146 adolescents 49 were diagnosed with EIB. Forty-six of the adolescents with EIB (35 girls and 11 boys) and 84 of the control adolescents (45 girls and 39 boys) had complete 7 day activity diary and accelerometer data. There were no differences in age, BMI and sleep between EIB and control adolescents. Boys with EIB overestimated subjective assessment compared to objective assessment more than girls with EIB. No difference was seen between control boys and girls. Furthermore, boys with EIB reported a much higher frequency of high intensity exercise than girls with EIB, but no difference was observed between control boys and girls. CONCLUSION: Adolescent boys with newly diagnosed EIB overestimated their physical activity compared to EIB girls. Caution may thus be used when choosing methods measuring level of physical activity in this group and especially when investigating gender differences.

BACKGROUND: Concerns for the possibility of an excessive loss of fat-free mass (FFM) and resting metabolic rate (RMR) after bariatric surgery, such as Roux-en-Y gastric bypass (RYGB) and duodenal switch (BPD/DS), have been raised. OBJECTIVES: This study aims to examine body composition and RMR in patients after RYGB and BPD/DS and in non-operated controls. METHODS: Body composition and RMR were studied with Bod Pod and indirect calorimetry in weight-stable RYGB (n = 15) and BPD/DS patients (n = 12) and compared with non-operated controls (n = 17). All patients were 30-55 years old and weight stable with BMI 28-35 kg/m(2). RESULTS: FFM% was 58% (RYGB), 61% (BPD/DS), and 58% (controls). Body composition did not differ after RYGB and BPD/DS compared to controls, despite 27 and 40% total body weight loss, respectively. No difference in RMR or RMR/FFM was observed (1539, 1617, and 1490 kcal/24 h; and 28.9, 28.4, and 28.8 kcal/24 h/kg). CONCLUSION: Weight-stable patients with BMI 28-35 kg/m(2) after RYGB and BPD/DS have a body composition and RMR similar to that of non-operated individuals within the same BMI interval.

Background: Age-related losses of muscle mass, strength, and function (sarcopenia) pose significant threats to physical performance, independence, and quality of life. Nutritional supplementation could positively influence aspects of sarcopenia and thereby prevent mobility disability. Objective: To test the hypothesis that a specific oral nutritional supplement can result in improvements in measures of sarcopenia. Design: A multicenter, randomized, controlled, double-blind, 2 parallel-group trial among 380 sarcopenic primarily independent-living older adults with Short Physical Performance Battery (SPPB; 0-12) scores between 4 and 9, and a low skeletal muscle mass index. The active group (n = 184) received a vitamin D and leucine-enriched whey protein nutritional supplement to consume twice daily for 13 weeks. The control group (n = 196) received an iso-caloric control product to consume twice daily for 13 weeks. Primary outcomes of handgrip strength and SPPB score, and secondary outcomes of chair-stand test, gait speed, balance score, and appendicular muscle mass (by DXA) were measured at baseline, week 7, and week 13 of the intervention. Results: Handgrip strength and SPPB improved in both groups without significant between-group differences. The active group improved more in the chair-stand test compared with the control group, between-group effect (95% confidence interval): -1.01 seconds (-1.77 to -0.19), P = .018. The active group gained more appendicular muscle mass than the control group, between-group effect: 0.17 kg (0.004-0.338), P = .045. Conclusions: This 13-week intervention of a vitamin D and leucine-enriched whey protein oral nutritional supplement resulted in improvements in muscle mass and lower-extremity function among sarcopenic older adults. This study shows proof-of-principle that specific nutritional supplementation alone might benefit geriatric patients, especially relevant for those who are unable to exercise. These results warrant further in

AimThis study compared daily activity energy expenditure (AEE) in children with cerebral palsy with a control group and investigated whether the children achieved healthy levels of physical activity. MethodsWe enrolled eight children with bilateral cerebral palsy, from eight to 10years of age, and a group of controls matched for age and gender. For three days, physical activity was simultaneously measured by accelerometers and self-reports using a diary. The daily AEE results were compared between groups and methods. The number of children that achieved healthy physical activity levels in each group was explored. ResultsChildren with cerebral palsy had significantly lower daily AEE, as measured by accelerometers, than the controls, and they did not achieve the healthy moderate to heavy physical activity level defined in the Nordic Nutrition Recommendations. Self-reports using the diaries resulted in an overestimation of physical activity compared with the ankle accelerometer measurements in both groups. ConclusionOur investigation of physical activity in children with cerebral palsy and controls using accelerometers and a diary found low levels of daily AEE and physical activity, and these results were most prominent in the group with cerebral palsy. The diaries overestimated physical activity in both groups.

Background: Ghrelin and obestatin are derived from the same peptide hormone precursor and are mainly produced by the gastric mucosa. Ghrelin is involved in many biological processes, whereas the physiological function of obestatin needs further investigation. The aims of the present study were to establish the incidence of ghrelin- and obestatin-immunoreactive cells in a comprehensive panel of human neuroendocrine tumors (NETs) and to investigate if blood obestatin concentrations are influenced during a standardized meal stimulation test in healthy individuals and patients with NETs. Materials and Methods: The expression of ghrelin and obestatin was investigated in NETs (n = 149) and other endocrine-related disorders (n = 3) using immunohistochemistry with specific polyclonal antibodies. Coexpression of the peptides was evaluated by double immunofluorescence. Concentrations of obestatin in blood were measured during a meal test in 6 healthy individuals and 5 patients with pancreatic NETs. Results: Ghrelin and obestatin were expressed in 14/152 and 19/152 tumor tissues, respectively, mainly representing NETs of foregut origin and in pancreatic tissue from a nesidioblastosis patient. Double immunofluorescence staining showed colocalization of the peptides. During the meal test, obestatin levels in blood were unchanged in all patients but decreased significantly in the healthy individuals. Conclusion: Only a minority of NETs express ghrelin and obestatin. However, analysis of patients with tumors originating from tissues that express the peptides in normal conditions could be of importance. The results from the meal test indicate that the hormone levels are affected by food intake in healthy individuals, whereas obestatin levels remained unchanged in pancreatic NET patients.

Background: Short sleep duration has been linked to impaired glucose metabolism in many experimental studies. Moreover, studies have reported indications of an increased metabolic stress following sleep restriction. Objective: We aimed to investigate the effects of partial sleep deprivation on markers of glucose metabolism. Additionally, we aimed to investigate if short sleep duration induces a state of endocrine stress. Design: A randomized crossover design, with 2 experimental conditions: 3 consecutive nights of short sleep (SS, 4 h/night) and long sleep (LS, 9 h/night) duration. Subjects and Measurements: In 21 healthy, normal-weight male adolescents (mean +/- SD age: 16.8 +/- 1.3 y) we measured pre- and post-prandial glucose, insulin, C-peptide, and glucagon concentrations. Furthermore, we measured fasting cortisol, 24-h catecholamines, and sympathovagal balance. Results: Fasting insulin was 59% higher (P = 0.001) in the SS than the LS condition as was both fasting (24%, P < 0.001) and post-prandial (11%, P = 0.018) C-peptide. Pre- and post-prandial glucose and glucagon were unchanged between conditions. The homeostasis model assessment of insulin resistance (HOMA-IR) index was 65% higher (P = 0.002) and the Matsuda index was 28% lower (P = 0.007) in the SS condition compared to the LS condition. The awakening cortisol response and 24-h norepinephrine were not affected by sleep duration, whereas 24-h epinephrine was 24% lower (P = 0.013) in the SS condition. Neither daytime nor 24-h sympathovagal balance differed between sleep conditions. Short wave sleep was preserved in the SS condition. Conclusion: Short-term sleep restriction is associated with decreased insulin sensitivity in healthy normal-weight adolescent boys. There were no indications of endocrine stress beyond this.

A growing body of observational evidence suggests that short sleep duration is a risk factor for the development of obesity. Although increased energy intake is the most prevailing causal explanation for this association, we should also consider possible effects on energy metabolism to understand fully the potential impact of short sleep duration on the regulation of energy balance. We performed a search of the literature from 1970 to 2011, including original papers, investigating the relation between short sleep and energy metabolism in animals and humans. Although the limited number of experimental studies in humans precludes any definitive conclusions about causality, short sleep duration does not seem to substantially affect total daily energy expenditure, nor is there sufficient evidence in support of any meaningful effect of restricted sleep on the specific components of energy metabolism (i.e. resting metabolic rate, intentional as well as unintentional physical activity, diet-induced thermogenesis, and substrate utilization). As studies on rats suggest that other factors that can potentially influence energy metabolism could be affected (i.e. hormonal systems and thermoregulation), we included these factors in our literature search and found some indications in support of an up-regulation of thyroid hormones and glucocorticoids as well as increased heat dissipation following total or severe sleep deficit. Although we found some evidence also in humans that suggests a possible effect on energy metabolism, the limitations of the studies make it difficult to draw conclusions on the effect of short sleep on energy metabolism under relevant free living conditions. To explore this area further, more studies using suitable methodology under relevant conditions to mimic real-life situations are needed.

Background: A short sleep (SS) duration has been linked to obesity in observational studies. However, experimental evidence of the potential mechanisms of sleep restriction on energy balance is conflicting and, to our knowledge, nonexistent in adolescents. Objective: We investigated the effects of 3 consecutive nights of partial sleep deprivation on components of energy balance. Design: In a randomized, crossover design, 21 healthy, normal-weight male adolescents (mean +/- SD age: 16.8 +/- 1.3 y) completed the following 2 experimental conditions, each for 3 consecutive nights: an SS (4 h/night) and a long sleep (LS; 9 h/night) duration. Endpoints were 24-h energy expenditure (EE), spontaneous physical activity (SPA), postintervention diet-induced thermogenesis (DIT), appetite sensations, ad libitum energy intake (EI), and profiles of plasma ghrelin and leptin. Results: The 24-h EE on day 3 was 370 +/- 496 kJ higher in the SS condition than in the LS condition (P = 0.003). This difference in EE was explained by prolonged wakefulness in the SS condition and a 19% higher SPA (P = 0.003). In a postintervention breakfast-meal challenge, there was a 0.19-kJ/min smaller incremental AUC in DIT over 4 h in the SS condition than in the LS condition (P = 0.012) with no time X condition effect (P = 0.29). Subjects consumed 13% less energy in the ad libitum meal in the SS condition (P = 0.031), with a concomitant decreased motivation to eat. Concentrations of ghrelin and leptin remained unchanged with sleep restriction. Conclusion: Short-term sleep restriction in male adolescents is associated with a small negative energy balance driven by increased EE from prolonged wakefulness and a concomitant decreased El and motivation to eat. This trial was registered at clinicaltrials.gov as NCT01198431.

Compared to individuals who work during the day, shift workers are at higher risk of a range of metabolic disorders and diseases (eg, obesity, cardiovascular disease, peptic ulcers, gastrointestinal problems, failure to control blood sugar levels, and metabolic syndrome). At least some of these complaints may be linked to the quality of the diet and irregular timing of eating, however other factors that affect metabolism are likely to play a part, including psychosocial stress, disrupted circadian rhythms, sleep debt, physical inactivity, and insufficient time for rest and revitalization. In this overview, we examine studies on food and nutrition among shift workers [ie, dietary assessment (designs, methods, variables) and the factors that might influence eating habits and metabolic parameters]. The discussion focuses on the quality of existing dietary assessment data, nutritional status parameters (particularly in obesity), the effect of circadian disruptions, and the possible implications for performance at work. We conclude with some dietary guidelines as a basis for managing the nutrition of shift workers.

Background: Disturbed sleep is a major risk factor for metabolic disturbances, including type 2 diabetes, but the involved mechanisms are still poorly understood. We investigated how an acute shift of sleep to the daytime affected IGF-binding protein 1 (IGFBP1), which is a risk factor for diabetes. Methods: Seven healthy men (age, 22-32 years) participated in a night sleep condition (sleep 2300-0700 h) and a day sleep condition (0700-1500 h) with hourly blood samples taken for 25 h (starting at 1900 h) and isocaloric meals every 4th hour awake. The blood samples were analyzed for IGFBP1, insulin, GH, glucose, and cortisol. Result: The acute shift of sleep and meal timing (to 8 h) shifted the 24-h patterns of IGFBP1, glucose, insulin, and GH to a similar degree. However, the day sleep condition also resulted in elevated levels of IGFBP1 (area under curve (AUC)+22%, P < 0.05), and reduced glucose levels (AUC-7%, P < 0.05) compared with nocturnal sleep. Sleeping during the day resulted in elevated cortisol levels during early sleep and reduced levels in late sleep, but also in increased levels the subsequent evening (P's < 0.05). Conclusion: Sleep-fasting seems to be the primary cause for the elevation of IGFBP1, irrespective of sleep timing. However, sleeping during the day resulted in higher levels of IGFBP1 than nocturnal sleep, suggesting altered metabolism among healthy individuals, which may have implications for other groups with altered sleep/eating habits such as shift workers. Moreover, sleep and meal times should be accounted for while interpreting IGFBP1 samples.

Aims To study if there is a change in paediatric overweight/obesity prevalence from 1982 to 2002 in a population with a high proportion of post-graduate education. Design Two samples of children in Uppsala County, Sweden, were compared: children who were 4, 10 and 16 year old in 1982; or 4, 10 and 16 year old in 2002. Mean BMI (in the lowest 10%, middle 50% and highest 10%) and ISO-BMI ('age adjusted BMI') cut-off values were calculated in each age and gender group. Results Using the mean BMI or ISO-BMI cut-off values, the BMI-distribution shifted from 1982 to 2002. More 4- and 10-year-old girls and boys were overweight/obese, although this shift was larger in girls. No shift was seen in the 16-year-olds, only the middle 50% group in the 16-year-old girls had a slight increase of their mean BMI. In the 2002 4-year-old, and both 10-year-old samples, a higher proportion of the girls were overweight/obese compared to the boys, but no difference was seen in the 16-year-old sample. Conclusion Young children, especially girls, have become much more overweight/obese during the past 20 years, despite a high proportion of post-graduate education in the population. The lack of major change in 16-year-olds may suggest a rather recent change in the children's environment/lifestyle.

Background: Sleep exerts important modulatory effects on neuroendocrine function and glucose regulation. During the past few decades, sleep curtailment has become a very common behavior in industrialized countries. This trend toward shorter sleep times has occurred over the same time period as the dramatic increases in the prevalence of obesity and diabetes. Aims: This article will review rapidly accumulating laboratory and epidemiologic evidence indicating that chronic partial sleep loss could play a role in the current epidemics of obesity and diabetes. Conclusions: Laboratory studies in healthy young volunteers have shown that experimental sleep restriction is associated with a dysregulation of the neuroendocrine control of appetite consistent with increased hunger and with alterations in parameters of glucose tolerance suggestive of an increased risk of diabetes. Epidemiologic findings in both children and adults are consistent with the laboratory data.

Physical activity has been shown to favorably affect metabolic risk markers, including blood lipids. The impact of high-energy turnover, without influencing the traditionally used markers of exercise training effects, on blood lipids is still unclear. The aim was to study the effect of high-volume low-intensity physical activity on the blood lipid pattern, with a tight control of diet and energy balance. Eight untrained men [42.5 (12.1) years, body mass index 24.2 (2.8) kg m(-2)] were tested in two different 6-week protocols. In the sedentary protocol, the subjects were instructed to limit their everyday physical activity. In the activity protocol, a 2-h physical activity bout was performed 5 days week(-1) (~40% of VO(2max); equivalent of an additional 21 MJ week(-1) in energy expenditure). The diet for both protocols comprised ~40 energy percent (E%) fat, ~50 E% carbohydrates (CHO). The polyunsaturated fatty acids to saturated fatty acids ratio of the diet was ~0.12. There were no changes during each 6-week period or differences between the two protocols in body weight, body composition or aerobic capacity. Low-intensity physical activity did not affect lipid parameters substantially, except for a slightly lower Apo-B/Apo-A1 ratio with the activity protocol (P<0.05). Total and low-density lipoprotein cholesterol, as well as Apo-B and Apo-A1, were increased during the beginning of each 6-week period (P<0.05), but returned to basal levels by the sixth week. In conclusion, 6 weeks of high-volume low-intensity physical activity did not affect blood lipids substantially.

CONTEXT: It is not yet clear whether the diurnal variation in testosterone is regulated by circadian or homeostatic (sleep) influences. OBJECTIVE: The present study tested whether testosterone is driven by a circadian-independent sleep effect by shifting sleep acutely to daytime in a 24-h sampling regiment. DESIGN, SETTING, AND PARTICIPANTS: In the sleep laboratory, seven healthy young men (age, 22-32 yr) participated in three conditions: habituation (sleep between 2300-0700 h), night sleep (2300-0700 h), and day sleep (0700-1500 h), the latter two in a balanced order. INTERVENTION AND MAIN OUTCOME MEASURE: Serum testosterone was, in all conditions, sampled by hourly blood drawing for 24 h during constant bed rest. RESULTS: Mean testosterone levels increased as a log-linear function of time (hours) across both sleep periods (b = 4.88; P < 0.001), from 15.3 +/- 2.1 to 25.3 +/- 2.2 nmol/liter during night sleep and from 17.3 +/- 2.1 to 26.4 +/- 2.9 nmol/liter during day sleep. Similarly, mean testosterone levels decreased with time (log-linear) awake (b = -1.80; P < 0.001). There was also evidence of a weak circadian component (acrophase ranging between 0651-0924 h) and an increase with time in the laboratory. Moreover, all these effects, except for the increase during sleep, differed significantly between individuals. CONCLUSION: In conclusion, testosterone increased during sleep and fell during waking, whereas circadian effects seemed marginal. Individual differences were pronounced.

Background: Night work is becoming more common and shift workers display several metabolic disturbances. Aim: To study the endocrine responses in relation to time of day during a 24-h period and how dietary macronutrient composition affects these responses. Design: Seven males (26-43 y and 19.9-26.6 kg · m-2) were studied in a crossover design. Isocaloric diets described as highcarbohydrates (HC; 65 energy percent (E%) carbohydrates and 20E% fat) or high-fat (HF; 40E% carbohydrates and 45E% fat) were given. After a 6-day diet adjustment period, the subjects were kept awake for 24 h in a metabolic unit and were served an isocaloric meal (continuation of respective diet) every 4-h. Blood samples were taken throughout the 24-h period. Results: Insulin and leptin responses to meal intake differed with respect to time of day (p ≤ 0.05). Time of day affected glucagon, thyroid stimulating hormone (TSH), free thyroxin (fT4), total triiodothyronine (tT3), cortisol, chromogranin A (CgA) and pancreatic polypeptide (PP) concentrations (p ≤ 0.05). Meal intake decreased cortisol concentration after meals at 0800, 1200 and 0400 but not at 1600, 2000 and 0000 h. The PP's postprandial increase was greater during 0800-1600 h compared to 2000-0800 h. With the HC meals, lower glucagon and CgA concentrations (p ≤ 0.05), and a tendency for lower tT3 concentrations (p = 0.053) were observed compared to the HF meals. Conclusion: Insulin, PP, TSH, fT4, cortisol and leptin responses to meal intake differed with respect to time of day. The decreased evening/nocturnal responses of cortisol and PP to meal intake indicate that nocturnal eating and night work might have health implications.

Because ∼20% of the work force in the industrialized world have irregular working hours, it is pertinent to study the consequences of eating at irregular, especially nighttime hours. We studied the postprandial responses during nocturnal fasting vs. e+ating throughout a 24-h wake period. Seven healthy males were studied twice in a crossover design. After a 6-d diet adjustment period [high fat diet, 45 energy percent (en%) fat, 40 en% carbohydrates)] with sleep from 2300 to 0700 h, the men were kept awake for 24 h at the metabolic ward and given either 6 isoenergetic meals, i.e., every 4 h (N-eat) or 4 isoenergetic meals from 0800 to 2000 h followed by a nocturnal fast (N-fast), with the same 24-h energy intake. Energy expenditure, substrate utilization, activity, heat release, body temperature and blood variables were measured over 24 h. Energy expenditure and blood glucose, triacylglycerol, insulin and glucagon concentrations were lower and nonesterified fatty acids concentrations were higher during the nocturnal fast than during nocturnal eating (P < 0.05); however, no 24-h differences between the protocols were apparent. Nocturnal fasting slightly altered the secretory patterns of the thyroid hormones and cortisol (P < 0.05). We found no clear indication that it would be more favorable to ingest few larger daytime meals than smaller meals throughout the 24-h period. The body seems to be able to buffer small differences in meal size and timing provided energy balance is maintained

Because night work is becoming more prevalent, we studied whether feeding at different times of a 24-h period would elicit different metabolic responses and whether dietary macronutrient composition would affect these responses. Seven men (26-43 y, 19.9-26.6 kg/m(2)) consumed two isocaloric diets, in a crossover design. The diets were a high carbohydrate (HC) diet [65 energy % (E%) carbohydrates, 20E% fat] and a high fat (HF) diet (40E% carbohydrates, 45E% fat). After a 6-d diet-adjustment period, the men were kept awake for 24 h and the food (continuation of respective diet) was provided as six isocaloric meals (i.e., every 4 h). Energy and substrate turnover, heart rate, mean arterial pressure (MAP), blood glucose, triacylglycerol (TAG), nonesterified fatty acid (NEFA) and glycerol were measured throughout the 24-h period. Significantly higher energy expenditure and NEFA concentration, and lower blood glucose and TAG concentrations were observed when the men consumed the HF diet than when they consumed the HC diet. Significant circadian patterns were seen in body and skin temperature (nadir, 0400-0500 h). When the men consumed the HF diet, significant circadian patterns were seen in fat oxidation (nadir, 0800-1200 h; plateau, 1200-0800 h), heat release (nadir, 0800-1200 h; plateau, 1600-0800 h), heart rate (nadir, 0000 h), blood glucose (nadir, 0800-1200 h; peak, 0000-0400 h), NEFA (nadir, 0800-1200 h; peak, 1200-2000 h) and TAG (nadir, 0800-1200 h; peak, 0400-0800 h) concentrations. Energy expenditure, carbohydrate oxidation, MAP and glycerol concentration did not display circadian patterns. Unequal variances eradicated most circadian effects in the HC-diet data. The increased TAG concentration in response to feeding at 0400 h might be involved in the higher TAG concentrations seen in shift workers. Distinct macronutrient/circadian-dependent postprandial responses were seen in most studied variables.

Because night work is becoming more prevalent, we studied whether feeding at different times of a 24-h period would elicit different metabolic responses and whether dietary macronutrient composition would affect these responses. Seven men (26-43 y, 19.9-26.6 kg/m2) consumed two isocaloric diets, in a crossover design. The diets were a high carbohydrate (HC) diet [65 energy % (E%) carbohydrates, 20E% fat] and a high fat (HF) diet (40E% carbohydrates, 45E% fat). After a 6-d diet-adjustment period, the men were kept awake for 24 h and the food (continuation of respective diet) was provided as six isocaloric meals (i.e., every 4 h). Energy and substrate turnover, heart rate, mean arterial pressure (MAP), blood glucose, triacylglycerol (TAG), nonesterified fatty acid (NEFA) and glycerol were measured throughout the 24-h period. Significantly higher energy expenditure and NEFA concentration, and lower blood glucose and TAG concentrations were observed when the men consumed the HF diet than when they consumed the HC diet. Significant circadian patterns were seen in body and skin temperature (nadir, 0400-0500 h). When the men consumed the HF diet, significant circadian patterns were seen in fat oxidation (nadir, 0800-1200 h; plateau, 1200-0800 h), heat release (nadir, 0800-1200 h; plateau, 1600-0800 h), heart rate (nadir, 0000 h), blood glucose (nadir, 0800-1200 h; peak, 0000-0400 h), NEFA (nadir, 0800-1200 h; peak, 1200-2000 h) and TAG (nadir, 0800-1200 h; peak, 0400-0800 h) concentrations. Energy expenditure, carbohydrate oxidation, MAP and glycerol concentration did not display circadian patterns. Unequal variances eradicated most circadian effects in the HC-diet data. The increased TAG concentration in response to feeding at 0400 h might be involved in the higher TAG concentrations seen in shift workers. Distinct macronutrient/circadian-dependent postprandial responses were seen in most studied variables.