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Predictive equations are widely employed for estimating the volume of oxygen consumption (VO2) while walking, which is ultimately employed to determine energy expenditure and tailor exercise prescription. This study aimed to test the agreement between the measured VO2 and estimated VO2 during a walking protocol on a treadmill at 3.5, 4.5, 5.5, and 6.5 km/h. Thirty‐eight young adults (50% women) participated in this cross‐sectional study. The Omnical (Maastricht Instruments, Maastricht, The Netherlands) and K5 (Cosmed, Rome, Italy) metabolic systems were used to measure VO2. To determine the predictive equations, a comprehensive literature search was conducted using the MEDLINE database from May 2022 to July 2023. Seven predictive equations were found and included for estimating VO2 values. We calculated the mean bias (mean difference between measured VO2 and estimated VO2) obtained at each speed using one‐sample t‐tests. We compared the VO2 measured and estimated values using repeated measures analysis of variance and the Bland–Altman method. One‐sample t‐tests showed that all score errors were different from zero (ranging from 1.1 to 5.4 mL/kg/min). Thus, no predictive equation estimated similar VO2 values in comparison with the Omnical and K5 metabolic systems at all intensities. However, the Weyand equation showed the lowest bias across all intensities (score error of 1.1 mL/kg/min). This study showed a lack of agreement between the Omnical and K5 systems compared to diverse predictive equations specially designed to estimate VO2 during walking. Nevertheless, based on our results, the Weyand equation should be the preferred option. Highlights: The estimated VO2 values derived from all predictive equations showed no agreement with VO2 values measured by the Omnical and K5 metabolic systems, highlighting the importance of taking into account the error introduced by VO2 walking predictive equations when estimating VO2.The Weyand equation presented the lowest bias in comparison to the VO2 measured by the Omnical metabolic cart, which is the gold‐standard metabolic cart (i.e., system of reference).These findings may hold practical implications when transitioning from clinically based programs to exercise interventions tailoring or self‐guided exercise programs in young adults. Moreover, these results can contribute to individualize exercise programs by sport scientists using freely available and affordable tools as predictive equations. [ABSTRACT FROM AUTHOR]

Objective: To determine differences in resting heart rate variability (HRV) and heart rate (HR) between young adults with normal‐weight obesity (NWO) and normal‐weight lean (NWL). Methods: A total of 65 normal‐weight individuals (18–25 years old, 50 women, body mass index 18.5 to 24.9 kg/m2) were included in this cross‐sectional study. Body fat percentage was determined using a whole‐body dual energy x‐ray absorptiometry scanner. Resting HRV and HR were assessed with the Polar RS800CX. Forty‐one participants were classified as NWO and 24 NWL using cutoff points for body fat percentage (33.3% for women and 23.1% for men). Results: There were no differences in HRV between NWO and NWL groups (all p >.05). HR was higher in NWO (mean 70 beats per minute [bpm], standard deviation [SD] 8) than in NWL adults (mean 65 bpm, SD 10), the adjusted mean difference 5 bpm (95% CI, 0 to 10 bpm). Conclusion: HR is a noninvasive biomarker and relatively cheap, fast, and easy to measure that could detect "apparently healthy" young individuals with an adverse cardiovascular disease risk profile despite presenting a normal body weight. [ABSTRACT FROM AUTHOR]

Context The endocannabinoid system (ECS) is a signaling system composed of endocannabinoids (eCBs), their receptors, and the enzymes involved in their synthesis and metabolism. Alterations in the ECS are linked to the development of cardiometabolic diseases. Objective Here, we investigated the relationship between plasma levels of eCBs and their analogues with body composition and cardiometabolic risk factors. Methods The study included 133 young adults (age 22.1 ± 2.2 years, 67% women). Fasting plasma levels of eCBs and their analogues were measured using liquid chromatography-tandem mass spectrometry. Body composition, brown adipose tissue (BAT) volume, glucose uptake, and traditional cardiometabolic risk factors were measured. Results Plasma levels of eCBs and several eCB analogues were positively correlated with adiposity and traditional cardiometabolic risk factors (eg, serum insulin and triacylglyceride levels, all r ≥ 0.17 and P ≤.045). Plasma levels of 2-arachidonoyl glycerol and N-pentadecenoylethanolamine were negatively correlated with BAT volume and glucose uptake (all r ≤ −0.17 and P ≤.047). We observed that the plasma levels of eCBs and their analogues were higher in metabolically unhealthy overweight–obese participants than in metabolically healthy overweight–obese participants. Conclusion Our findings show that the plasma levels of eCBs and their analogues are related to higher levels of adiposity and worse cardiometabolic profile. [ABSTRACT FROM AUTHOR]

Concurrent training has been postulated as an appropriate time‐efficient strategy to improve physical fitness, yet whether the exercise‐induced adaptations are similar in men and women is unknown. An unblinded randomized controlled trial was conducted to investigate sex‐specific dose–response effects of a 24‐week supervised concurrent exercise training program on cardiorespiratory fitness and muscular strength in young adults. One hundred and forty‐four sedentary adults aged 18–25 years were assigned to either (i) a control group (n = 54), (ii) a moderate intensity exercise group (MOD‐EX, n = 46), or (iii) a vigorous intensity exercise group (VIG‐EX, n = 44) by unrestricted randomization. Cardiorespiratory fitness (VO2max), hand grip strength, and one‐repetition maximum of leg press and bench press were evaluated at baseline and after the intervention. A total of 102 participants finished the intervention (Control, n = 36; 52% women, MOD‐EX, n = 37; 70% women, and VIG‐EX, n = 36; 72% women). In men, VO2max significantly increased in the MOD‐EX (~8%) compared with the control group and in the VIG‐EX group after the intervention (~6.5%). In women, VO2max increased in the MOD‐EX and VIG‐EX groups (~5.5%) compared with the control group after the intervention. There was a significant increment of leg press in the MOD‐EX (~15.5%) and VIG‐EX (~18%) groups compared with the control group (~1%) in women. A 24‐week supervised concurrent exercise was effective at improving cardiorespiratory fitness and lower body limbs muscular strength in young women—independently of the predetermined intensity—while only at moderate intensity improved cardiorespiratory fitness in men. [ABSTRACT FROM AUTHOR]

The standard method for identifying active Brown Adipose Tissue (BAT) is [ 18 F]-Fluorodeoxyglucose ([ 18 F]-FDG) PET/CT imaging, which is costly and exposes patients to radiation, making it impractical for population studies. These issues can be addressed with computational methods that predict [ 18 F]-FDG uptake by BAT from CT; earlier population studies pave the way for developing such methods by showing some correlation between the Hounsfield Unit (HU) of BAT in CT and the corresponding [ 18 F]-FDG uptake in PET. In this study, we propose training convolutional neural networks (CNNs) to predict [ 18 F]-FDG uptake by BAT from unenhanced CT scans in the restricted regions that are likely to contain BAT. Using the Attention U-Net architecture, we perform experiments on datasets from four different cohorts, the largest study to date. We segment BAT regions using predicted [ 18 F]-FDG uptake values, achieving 23% to 40% better accuracy than conventional CT thresholding. Additionally, BAT volumes computed from the segmentations distinguish the subjects with and without active BAT with an AUC of 0.8, compared to 0.6 for CT thresholding. These findings suggest CNNs can facilitate large-scale imaging studies more efficiently and cost-effectively using only CT., (© 2024. The Author(s).)

Stroke is the leading cause of disability and the second cause of death worldwide. The increasing burden of stroke underscores the importance of optimising rehabilitation protocols. Virtual reality (VR) can improve poststroke prognosis. A VR software combining gamification, full immersion and stroke specificity (ie, the Development and validation of a novel viRtual rEality software for improving diSability and quality of lifE in patients with sTroke (RESET) software) might substantially improve disability and quality of life (QoL). However, this technology is still very scarce. The RESET trial aims to assess the effects of an early 10-week gamified, fully immersive and stroke-specific VR intervention (ie, starting at week 3 poststroke) on disability and QoL in people with stroke in the subacute phase. People with ischaemic or haemorrhagic stroke (n=94) aged ≥ 18 years will be randomised to receive (1) usual care (UC), (2) commercial VR or (3) gamified, fully immersive and stroke-specific VR ( RESET ). The three groups will receive UC (ie, three sessions/week of 90 min of standard rehabilitation). The VR groups will additionally receive three VR sessions of 20 min per week. The outcome measures will be assessed at baseline (week 2 from stroke occurrence), week 13 (approximately 90 days from the event) and week 26 (approximately 6 months from the event). The primary outcome is disability measured with the Barthel Index. Secondary outcomes include QoL, upper-extremity and lower-extremity motor function, gross manual dexterity, handgrip strength and cognitive function. This study will unravel the effects of a gamified, fully immersive and stroke-specific VR software on disability and QoL in patients with stroke in the early subacute phase.Trial registration number: NCT06132399., Competing Interests: None declared., (Copyright © Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Context: Exercise reduces adiposity, but its influence on bone marrow fat fraction (BMFF) is unknown; nor is it known whether a reduction in liver fat content mediates this reduction., Objectives: (i) To determine whether incorporating exercise into a lifestyle program reduces the lumbar spine (LS)-BMFF, and (ii), to investigate whether changes in liver fat mediate any such effect., Design: Ancillary analysis of a two-arm, parallel, non-randomized clinical trial., Setting: Primary care centres in Vitoria-Gasteiz (Spain)., Participants: A total of 116 children with overweight/obesity were assigned to a 22-week family-based lifestyle program (control group [n=57]) or the same program plus an exercise intervention (exercise group [n=59]., Interventions: The compared interventions consisted of a family-based lifestyle program (two 90-minute sessions/month) and the same program plus supervised exercise (three 90-minute sessions/week)., Main Outcomes and Measures: The primary outcome examined was the change in LS-BMFF between baseline and 22 weeks, as estimated by MRI. The effect of changes in hepatic fat on LS-BMFF were also recorded., Results: Mean weight loss difference between groups was 1.4±0.5 kg favour of the exercise group. Only the children in the exercise group experienced a reduction in LS-BMFF (effect size [Cohen d] -0.42, CI: -0.86, -0.01). Importantly, 40.9% of the reductions in LS-BMFF were mediated by changes in percentage hepatic fat (indirect effect: β=-0.104, 95%CI=-0.213, -0.019). The impact of changes in hepatic fat on LS-BMFF was independent of weight loss., Conclusions and Relevance: The addition of exercise to a family-based lifestyle program designed to reduce cardiometabolic risk improves bone health by reducing LS-BMFF in children with overweight or obesity. This beneficial effect on bone marrow appears to be mediated by reductions in liver fat., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society.)