Feel lonely? Get active: Exploring the daily relationship between accelerometer-measured physical activity and loneliness.

As life expectancy increases and the proportion of older adults grows worldwide, understanding how aging influences components of energy metabolism has become increasingly relevant. Diet-induced thermogenesis (DIT)-the increase in metabolic rate following food intake-accounts for approximately 10% of total daily energy expenditure. Aging has been proposed to attenuate DIT, potentially contributing to age-related reductions in energy expenditure and other metabolic changes. Here, we review available evidence from human studies on the effect of aging on DIT and explore potential methodological and physiological factors that may explain discrepancies across studies. Fourteen studies comparing younger and older adults were included. Six reported significantly lower DIT in older individuals, whereas eight found no age-related differences. One of the most consistent patterns identified across studies was the influence of postprandial measurement duration on study outcomes. Studies reporting lower DIT in older adults assessed postprandial energy expenditure over shorter durations (≤ 240min), while those employing longer measurement protocols found no differences. Variations in body composition, particularly a lower fat-free mass in older adults, were frequently observed but did not consistently explain the reported age effects. Mechanistic factors including sympathetic nervous system activity, gastric emptying, and macronutrient composition of the test meals have been investigated, yet available evidence does not support a consistent role for these factors in mediating age-related differences in DIT. Whether aging independently alters DIT in humans remains uncertain. The findings of this narrative review suggest that methodological factors, particularly the duration of measurement, may influence the detection of age-related differences in DIT. Future studies using adequately powered designs, standardized meal protocols, and matching or adjusting for body composition are required to clarify whether aging per se alters postprandial thermogenesis.

A multi-centre prospective evaluation of post-gastrostomy outcomes in patients with amyotrophic lateral sclerosis.

This study updates the average requirement for energy intake (AR-EI) for the Saudi population, thereby addressing outdated references. Previous estimates relied on generalized equations and non-specific data, which often led to overestimations. This study aimed to establish new AR-EI values for Saudi population. The study methodology combined two complementary approaches to estimate energy requirements. For adults, a factorial approach was used, incorporating physical activity levels observed in the Saudi population along with reference values for body weight and height, applied in published Saudi predictive equations for Basal Metabolic Rate (BMR). For infants, children, and adolescents (0-17 years), the study used Total Energy Expenditure (TEE) predictive equations derived from multi-country doubly labeled water (DLW) studies. After calculating the requirements across different age groups and sexes, the value representing the average that meets the needs of 50% of the population was identified and adopted as the AR-EI. The AR-EI values ranged from 393kcal/day during the first six months to 778kcal/day by 12 months for male infants, while female infants required 364-748kcal/day. Among children and adolescents, AR-EI values ranged from 912 to 3147kcal/day. For adults, the AR-EI was estimated at 2207kcal/day for men and 1708kcal/day for women under current activity levels. With increased physical activity, these requirements rose to 3153kcal/day for men and 2440kcal/day for women. This study identified significant overestimations in previous references owing to the reliance on generalized equations and outdated data. By incorporating Saudi-specific data, these findings provide accurate and practical benchmarks for energy intake. These results serve as a foundation for evidence-based nutritional guidelines, promoting public health and reducing the incidence of diet-related diseases.

Physical inactivity as an upstream driver of metabolic dysfunction: a perspective.

The fruit of Bassia scoparia(L.) A. J. Scott [syn. Kochia scoparia (L.) Schrad.], commonly known as mountain caviar, are traditionally consumed as both food and medicine. Oral administration of 65% aqueous ethanol mountain caviar extract (MCE, 125-250mg/kg) significantly suppressed postprandial plasma triglyceride (TG) elevation in olive oil-loaded mice. Among isolated saponins, the principal saponin momordin Ic exhibited significant antihyperlipidemic effect at 20mg/kg. HPLC quantitative analysis using charged aerosol detector revealed that momordin Ic accounted for 12.6% of the MCE. Mechanistic studies demonstrated that momordin Ic markedly delayed gastric emptying (GE) without inhibiting pancreatic lipase activity. Moreover, momordin Ic significantly enhanced plasma glucagon-like peptide-1 (GLP-1) levels. In a high-fat diet-fed (HFD) mice model, 14-day administration of MCE suppressed body weight gain. Similarly, momordin Ic (20mg/kg/day) significantly reduced visceral fat accumulation, liver cholesterol content, and plasma low-density lipoprotein/very low-density lipoprotein (LDL/VLDL) cholesterol levels, with a tendency to decrease plasma TG and total cholesterol. Notably, total energy expenditure measured using the doubly labeled water method was not significantly altered by MCE. These findings indicate that MCE and momordin Ic exert anti-obesity and lipid-lowering effects primarily through the suppression of dietary fat absorption and partly delayed GE, rather than by enhancing energy expenditure.

BackgroundUltramarathon performance reflects a complex interplay of physiological, biomechanical, and psychosocial factors, yet data from multi-day events remain limited, particularly in females. The demands and key determinants of performance in these events, including the longest ratified world-record event, the 6-day ultramarathon, are not well-characterized. This study aimed to provide a comprehensive, multi-disciplinary profile of the demands and performance determinants in an all-female 6-day ultramarathon.Methods10 heterogenous female athletes (27–48y, Tier 2–5, V̇O2 peak: 21.0–62.9 ml∙min–1·kg–1) ran a self-paced, certified 6-day ultramarathon. Data were collected over the preceding year, 2–4d pre-race, during the race, and post-race. We assessed V̇O2 peak with ventilatory thresholds and running economy; haemoglobin mass; body composition; total daily energy expenditure (TDEE, via doubly-labelled water) and dietary energy intake (EI); continuous heart rate, glucose, and core temperature; neuromuscular and cognitive fatigue; biomechanical parameters; in-race blood sampling to assess inflammatory markers; and psychosocial outcomes.ResultsAll athletes achieved personal distance records over 6 days (463.6±199.6 km), with the top athlete covering 901.8 km, breaking the female world record. Exercise intensity was low (~46±6%V̇O2 peak), but demands were extreme: up to 20 h·day−1 racing with 82,699±17,192 steps·day−1, total sleep 5.2±1.9 h·day−1, 4188±1109 kcal·day−1 EI, and 6698±2071 kcal·day−1 TDEE; including three of the highest female TDEEs reported. Average active race pace was 8:41±2:27 min:sec·km−1 and the average decline in running velocity from the first 2 days to the last 2 days was 9±13.1%. There was no evidence of neuromuscular or cognitive fatigue 24 h post-race. The top athlete, who ran 258.2 km farther than the next finisher, had similar lab-tested physiology compared to the next four top finishers, but spent the most time on course with the highest TDEE, EI, running and total step count, and exhibited significantly greater neuromuscular fatigue, inflammatory markers, sleep deprivation, and pacing decline. The only clear difference between the top athlete and the next 4 athletes was years of running experience (29 vs. 9.7±7.4 years).ConclusionsThe 6-day ultramarathon imposes an extreme physical and psychological challenge. Success may depend less on physical capacity and biomechanical efficiency than on the ability to persevere through fatigue.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40798-026-01041-w.

Characterization of dry- and fresh-period mammary plasma flow and metabolism and their association with colostrum production in multiparous Holstein cattle.

Indirect calorimetry in oncology: A case-based clinical tutorial.

Insulin resistance (IR) is a multifactorial metabolic condition influenced by lifestyle, body composition, and behavioral factors. Regular physical activity is known to improve insulin sensitivity, yet its associations with anthropometric and socio-demographic variables remain incompletely understood, particularly among young women. A total of 443 women aged 18-35 years participated in this cross-sectional study, including 301 with medically confirmed IR and 142 metabolically healthy controls. Anthropometric indices, Body Mass Index (BMI), Waist-Hip Ratio (WHR), Abdominal Volume Index (AVI), and Body Adiposity Index (BAI), were self-measured using standardized procedures. Physical activity was assessed via the Global Physical Activity Questionnaire (GPAQ), with total energy expenditure expressed as Metabolic Equivalent of Task (MET). Group comparisons were performed using Mann-Whitney U tests and Generalized Linear Models (GENLIN) with robust covariance estimation. Women with IR exhibited significantly higher BMI, WHR, AVI, and BAI values (all p < 0.001) and lower total physical activity (2,615 vs. 3,679 MET; p = 0.01) compared with controls. Sedentary behavior was more prevalent among IR participants (449 vs. 363 MET; p < 0.001). The observed differences were independent of anthropometric covariates. Socio-demographic factors showed nonlinear associations: lower and higher income levels, as well as rural residence, were linked to reduced activity in the IR group. Sleep duration showed no significant effect. Physical activity, independent of body composition, is a key determinant of metabolic health in women. The results highlight the need for targeted behavioral interventions promoting movement as a core therapeutic and preventive strategy in insulin resistance management.

Huddling and food availability shape seasonal torpor and energetics of juvenile garden dormice

The Goldberg method is a statistical approach suggested for identifying implausible energy intakes (EI) in nutritional epidemiology. However, estimating physical activity levels (PAL), required for the method, is challenging. We quantified the accuracy of the Goldberg method combined with PAL derived from the Sedentary Time and Activity Reporting Questionnaire (Goldberg-PALSTAR-Q). Total energy expenditure derived from doubly labeled water (TEEDLW) was the comparator. Between 2009 and 2011, men (n=40) and women (n=59) completed a two-week DLW protocol, a food frequency questionnaire, and the STAR-Q. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of the Goldberg-PALSTAR-Q were determined. Fifty-eight percent of men and women were classified as EI under-reporters by the Goldberg-PALSTAR-Q compared with 60% of men and 56% of women by TEEDLW. Among men, sensitivity, specificity, PPV, NPV and accuracy and 95% confidence intervals were 88% (68%-97%), 87% (61%-98%), 91% (72%-99%), 81% (56%-94%), and 87% (72%-95%), respectively; and among women 79% (62%-90%), 69% (50%-84%), 77% (60%-88%), 72% (52%-86%), and 75% (62%-84%), respectively. In studies where objective EI measures are lacking, the Goldberg method and individual-level questionnaire-derived PALs provide a viable option in sensitivity analyses exploring the influence of implausible EIs on diet and health-related associations.

The "Energetics of Gestation and Growth" (EGG) hypothesis proposes that human birth timing and the associated secondary altriciality of human newborns is determined by limits in maternal metabolic capacity. According to this model, labor is triggered when the increasing fetal energy requirements exceed the expectant mother's maximum sustained metabolic scope of 2.0-2.1 × basal metabolic rate (BMR). Because twin pregnancies generally involve higher combined fetal mass than singleton pregnancies, they provide an ideal test of the EGG hypothesis. Here, we use data from one study reporting maternal energy expenditure during twin pregnancy and seven studies that sonographically estimated twin fetal weights. Maternal metabolic scope during twin pregnancies exceeded the suggested metabolic ceiling without triggering earlier birth. Sensitivity analyses indicated that modest increases in total energy expenditure would raise maternal metabolic scope even further, reinforcing that our sample provides conservative estimates. Across studies, twins exhibited fetal growth ratios and energy requirement trajectories (estimated from fetal weight) that were similar to singletons, and variability in both measures increased with gestational age. Fetal energy requirements of two twins at the 50th percentile exceeded the proposed maternal metabolic ceiling in approximately pregnancy week 31, which was on average 5 weeks before birth. Crucially, higher fetal energy requirements were not consistently associated with shorter gestation lengths. These findings contradict the EGG hypothesis and indicate that energetic limits alone cannot explain birth timing or secondary altriciality, even under the substantial energetic load of twin gestations. Instead, the results highlight the adaptability of human maternal energetics.

The Nutrition Self-Assessment App (APP), a novel smartphone-based tool, was developed to enable users of oral nutritional supplements (ONSs) to self-assess total energy expenditure (TEE) and identify energy deficits, providing personalized ONS recommendations. By integrating step-count track-ing and dietary intake reporting, the app estimates physical activity levels and energy deficits. However, validation against clinician assessments is essential prior to large-scale implementation. In this multicenter cross-sectional study (October-November 2023), TEE and deficits were evaluated using both the app and clinician assessments. Statistical analyses included paired t-tests, intraclass correlation coefficients (ICC), and Bland-Altman plots. Clinician satisfaction was measured via a 5-point Likert scale. Among 423 ONS users, no significant differences were found between clinician- and app-derived estimates for TEE (1606.2 ± 287.2 vs. 1541.6 ± 300.5 kcal/day, p >0.05) or energy deficits (610.4 ± 376.9 vs. 600.1 ± 384.6 kcal/day, p >0.05). Agreement was moderate for TEE (ICC = 0.66) and excellent for deficits (ICC = 0.94). Bland-Altman analysis showed 93.9% (397/423) of deficit differences within 95% limits of agreement. Clinicians rated the app as "very satisfied" (46.1%) or "fairly satisfied" (37.1%) for most participants. The app demonstrated moderate agreement with clinician assessments for TEE estimation, while showing high agreement in energy deficit estimation. These findings validate its potential reliabil-ity as a supportive tool for ONS management. Its integration of activity tracking and dietary monitoring supports scalable implementation to improve ONS adherence.

ABSTRACTObjectiveTo compare metabolic adaptations at the early phase of weight loss in individuals with severe obesity assigned to two strategies of energy restriction: continuous or in combination with time‐restricted eating (TRE).Methods100 participants (> 40 kg/m2; 20–60 years) were randomized into two groups: continuous energy restriction (CER, n = 42) and TRE combined with energy restriction (TRE + ER; eating window: 10am‐6pm). Resting metabolic rate (RMR) by indirect calorimetry, body composition by dual‐energy X‐ray absorptiometry (DXA), serum hormones, and appetite feelings were evaluated at baseline and after 1 week of prescribed diet at 60% the total energy expenditure. Early adaptive thermogenesis (AT) was calculated using measured and predicted RMR. Data were evaluated using ANCOVA and linear mixed‐effects model.ResultsAfter adjustment for RMR at baseline and body composition, RMR after 1 week was similar between groups (β_group = 47 ± 32 kcal/day; p = 0.148). Early AT was significantly lower in the TRE + ER group (−13 ± 160 kcal vs. −83 ± 150 kcal; p = 0.038). After a week of energy restriction, leptin, insulin, and TSH concentrations decreased in both groups (time effect, p < 0.05) with no group x time interaction. The feeling of hunger increased after 1 week only in the CER group (p = 0.048).ConclusionResults suggest that TRE modestly attenuate early AT, but this effect does not translate into differences in RMR after 1 week. Hormonal and appetite responses were also not substantially affected by TRE. Further studies are needed to determine whether the modest early effects of TRE translate into clinically meaningful long‐term benefits for weight management.

People living with amyotrophic lateral sclerosis (ALS) are at high risk of malnutrition, making it essential to monitor their nutritional status through measurements of body composition and energy expenditure. However, validity of equations, as alternatives to reference standards for assessing these parameters in ALS, is unclear. This systematic review evaluates criterion validity of equations to estimate body composition and energy expenditure in ALS. Four electronic databases (EMBASE, MEDLINE, CINAHL and Cochrane) were systematically searched from inception until July 7th, 2025. Studies were included if criterion validity of an instrument or method for estimating body composition or energy expenditure was examined in people diagnosed with ALS. Methodological quality was assessed using the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) risk of bias checklist. Criterion validity was rated as sufficient (+), indeterminate (?) or insufficient (-) based on COSMIN criteria for good measurement properties. Results were qualitatively summarised. Twelve studies were included: five evaluated the criterion validity of equations to estimate body composition using Bioelectrical Impedance Analysis (BIA) or anthropometry, and seven to estimate resting or total daily energy expenditure. No equation was rated as sufficient for criterion validity across studies. Equations to estimate body composition and energy expenditure should be applied with caution, as no equation exhibited high criterion validity in ALS. ALS-specific equations require further validation, and ideally, new equations tailored to the unique physiological characteristics of ALS should be developed. CRD42024573509.

Selective separation of naphthalene sulfonic acids and salts from wastewater by electric field-assisted nanofiltration membranes.

Kıyıcı, F, Ulupınar, S, Gençoğlu, C, Atasever, G, Seren, K, Çiydem, Ç, and Özbay, S. Physiologic responses and energy system contributions in competitive short track speed skating across race distances. J Strength Cond Res XX(X): 000-000, 2026-This study aimed to quantify and compare the physiologic responses and energy system contributions across 3 standard race distances in elite short track speed skaters. Nine national-level elite male short track speed skaters performed maximal-effort time trials for 500, 1000, and 1,500 m, in randomized order and with full recovery between sessions. Oxygen uptake (V̇o2) was continuously measured using a portable gas analyzer, while blood lactate concentration ([BLa]) was sampled at rest and at multiple time points postexercise. Energy contributions from phosphagen, glycolytic, and aerobic pathways were calculated using validated equations based on V̇o2, EPOC kinetics, and [BLa]. Total energy expenditure increased with distance (500 m: 123.8 ± 16.5 kJ; 1,000 m: 163.1 ± 19.2 kJ; 1,500 m: 201.9 ± 19.6 kJ). Aerobic energy rose significantly from 27.2 ± 2.4 kJ at 500 m to 57.3 ± 4.9 kJ at 1,000 m and 89.1 ± 7.9 kJ at 1,500 m. Glycolytic energy was 50.6 ± 11.5 kJ at 500 m and 55.4 ± 10.6 kJ at 1,000 m, and increased to 60.3 ± 11.5 kJ at 1,500 m. Phosphagen energy also increased with distance (45.7 ± 9.4 kJ; 50.3 ± 10.3 kJ; 52.8 ± 11.2 kJ). In relative terms, aerobic contribution rose from 22.2% at 500 m to 35.3% at 1,000 m and 44.3% at 1,500 m, whereas glycolytic contribution declined from 40.9 to 33.9% and 29.8%, and phosphagen contribution from 36.9 to 30.8% and 26% (all p < 0.05). The findings demonstrate a clear shift from anaerobic to aerobic dominance as race distance increases in short track speed skating. The PCr-La-O2 approach offers detailed insights into metabolic demands across competition distances, supporting tailored training and recovery strategies. The observed nonlinear patterns in glycolytic and phosphagen contributions highlight the importance of distance-specific conditioning in elite speed skating performance.

Oral contraceptives containing ethinyl estradiol (EE) with levonorgestrel (LNG) are common in hormonal contraceptives. EE+LNG suppresses weight gain in rodents, but the mechanisms for this remain unclear. Further, metabolic demands in adolescence are increased relative to adulthood. We tested the metabolic effect of a low dose of EE + LNG in adolescents and adult female Long-Evans rats. Rats were given EE (10 µg/kg) + LNG (20 µg/kg) or vehicle subcutaneous injections daily for 16 days. Body mass, food intake, whole-body oxygen consumption, respiratory exchange ratio, and energy expenditure were measured in Promethion phenotyping cages. Dual-energy X-ray absorptiometry (DXA), glucose tolerance, serum metabolic hormone levels, depot-specific adipose and reproductive tissues were collected. EE+LNG limited body-mass gain in both age groups by combining hypophagia with a marked elevation in total energy expenditure and no change in locomotion, implicating potential thermogenic pathways. Dual-energy X-ray absorptiometry scans showed curtailed fat accrual and the preservation of lean mass in EE + LNG-treated rats. White-adipose depots were smaller in all hormone-treated rats, whereas brown adipose tissue mass was reduced only in adults. EE+LNG-treated adults had lower leptin and C-peptide levels with enhanced glucose clearance, whereas adolescents had reductions in GLP-1, glucagon, and PYY levels without altered glucose clearance. Thus low-dose EE + LNG reduced caloric intake, increased energy expenditure, and limited white-adipose deposition irrespective of age. Age-specific effects on metabolic hormones and adipose depot UCP1 content were noted. Together, these results delineate an age-sensitive metabolic and endocrine profile of EE + LNG.

Carnitine deficiency alters fuel metabolism and voluntary wheel running in mice.