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This 6‐week pilot study aimed to investigate the feasibility, perceived efficacy, and participation perspectives of a university campus stair climbing‐based exercise snack (ES) intervention and to compare it to moderate‐intensity continuous training (MICT). Healthy, young, inactive adults (age: 21.6 ± 2.3 years, BMI: 22.5 ± 3.6 kg/m2) were randomly assigned to three groups (ES, MICT, and Control [CON]). ES (n = 14, 6 females) and MICT (n = 13, 9 females) groups performed three sessions per week over 6 weeks, while the control group (n = 15, 9 females) maintained their habitual lifestyle. ES involved 3 × ~30 s 'all‐out' stair‐climbing (6 flights, total 126 steps and 18.9 m elevation) bouts separated by > 1 h rest, and MICT involved 40 min stationary cycling at 60%–70% HRmax. Mixed linear effect models were used to explore within and between‐group differences, and the change in magnitude was determined using mean difference (MD), 95% confidence interval (CI), and Cohen's d effect size. Fourteen participants also completed post‐intervention semi‐structured interviews. Retention rates of 93% (ES, 14/15), 93% (MICT, 13/14), and 100% (CON, 15/15) were achieved from baseline to post‐assessments, with compliance (participants' attendance to scheduled ES sessions) of 97% (733/756 sessions) and 93% (217/234 sessions) in ES and MICT, respectively. No significant differences were found between ES and MICT for future intentions (4.8 ± 1.4 and 5.0 ± 0.9), enjoyment (PACES, 89.0 ± 16.4 and 94.5 ± 11.9), and satisfaction. A significant group × time interaction was found in the quality of life and perceived stress. ES and MICT significantly increased the quality of life by 8% (MD = 5.5 [95% CI = 0.3, 10.7], Cohen's d = 0.64) and 6% (MD = 4.6 [95% CI = 0.9, 8.2], Cohen's d = 0.88) compared to baseline, whereas CON experienced a significant decrease (MD = −7.9 [95% CI = −14.4, −1.6], Cohen's d = 0.56). ES significantly decreased perceived stress by 7% (MD = −4.6 [95% CI = −8.9, −0.3], Cohen's d = 0.58), while MICT (MD = 2.0 [95% CI = −0.1, 4.1], Cohen's d = 0.28) and CON (MD = −2.4 [95% CI = −6.1, 1.3], Cohen's d = 0.22) had no significant effects. The majority (12/14) of participants generally demonstrated positive attitudes toward participation in ES and found it easier than expected while highlighting enablers, barriers, and future recommendations. Stair climbing‐based ES could be integrated into the campus setting, appeared feasible, and was similar to MICT regarding future intentions, enjoyment, and satisfaction. Both ES and MICT might induce relevant positive effects on the quality of life, and ES demonstrated greater benefits compared to MICT or CON for reducing perceived stress. Interviews provided positive insights into fostering adherence to ES among university students. [ABSTRACT FROM AUTHOR]

This article comments on a recent study about high-intensity interval training (HIIT) and its methodological problems. The authors agree with the study's identification of issues in research on the affective responses to HIIT but argue that the study's guidance on quantifying exercise intensity during HIIT is flawed. They propose using a percentage of peak workload during an incremental test as a more appropriate measure of exercise intensity. The authors also criticize the use of heart rate as a measure of intensity during interval exercise and suggest using metabolic landmarks instead. They provide examples from other studies to support their argument. Additionally, they refute criticisms regarding the appropriateness of HIIT intensities in studies comparing affective and enjoyment responses. [Extracted from the article]

The effects of exogenous ketones on appetite and food intake remain elusive, especially for people with type 2 diabetes (T2D). This study aimed to determine whether acute ingestion of an oral ketone monoester supplement (KME) affected appetite sensations, prospective food consumption and intake in T2D. Results showed that acute KME ingestion did not significantly alter appetite scores. However, there was a tendency for lower energy intake during an ad libitum meal 3 h following ketone ingestion compared to non-energetic placebo. Further research is warranted to understand the long-term effects of exogenous ketones for energy and macronutrient intake in T2D. [ABSTRACT FROM AUTHOR]

To determine how the anti-inflammatory actions of interleukin-10 (IL-10) and IL-6 differ across age and physical activity levels. Using a cross-sectional design, fasted blood samples were obtained from younger physically inactive (YI: n=10, age: 22.7 ± 3.7 years, BMI: 24.8 ± 4.8 kg/m2, <150 min of weekly moderate-to-vigorous physical activity [MVPA]), younger highly active (YA: n=11 varsity cross country running athletes, 20.7 ± 2.7 years, 21.1 ± 1.8 kg/m2, >300 min of weekly MVPA), and older highly active (OA: 12, 56.0 ± 10.3 years, 22.8 ± 3.2 kg/m2, >300 min of weekly MVPA) individuals and analyzed for leukocyte counts, IL-10 and IL-6-related signaling, and cytokine secretion ex vivo. Total white blood cells and monocytes were similar between groups (p=0.8) but YA and OA had lower lymphocyte counts than YI (p<0.01). The ability of IL-10 (1 ng/mL) to phosphorylate signal transducer and activator of transcription 3 (STAT3) in CD14 monocytes was greater in YA vs. YI (p<0.03) despite YA having lower IL-10 receptor expression (p<0.01). IL-6 (10 ng/mL) mediated STAT3 phosphorylation in CD4 lymphocytes was higher in OA compared YI (p<0.01), with a similar tendency observed for YA vs. YI (p=0.08). Despite enhanced responsiveness of STAT3 to IL-10/6 in active individuals, the ability of IL-10/6 to inhibit tumor necrosis factor-alpha (TNF-⍺) secretion from lipopolysaccharide-stimulated whole-blood was similar between groups. Highly active younger and older individuals demonstrate enhanced IL-10- and IL-6-mediated activation of immune cell STAT3. Although the ability of IL-10/6 to inhibit TNF-⍺ secretion appeared unimpacted by activity level, anti-inflammatory cytokine actions were preserved in older active individuals. [ABSTRACT FROM AUTHOR]

Exogenous ketone supplements have been suggested to have potential cardiovascular benefits, but their overall effect on blood pressure is unclear. Our objective was to perform a systematic review and meta-analysis on the effects of exogenous ketone supplements on blood pressure (BP) and concomitant changes in resting heart rate (HR). Five databases were searched on January 27th, 2023, for randomized and non-randomized studies. A random-effects model meta-analysis was performed including all studies jointly and separately for acute and chronic ingestion of ketone supplements. Out of 4012 studies identified in the search, 4 acute and 6 chronic studies with n = 187 participants were included. Pooled results (n = 10) showed no change in systolic (SMD [95% CI]= −0.14 [−0.40; 0.11]; I2= 30%; p = 0.17) or diastolic BP (−0.12 [−0.30; 0.05]; I2= 0%; p = 0.69), with a potential tendency observed toward increased resting heart rate (0.17 [-0.14; 0.47]; I2= 40%; p = 0.10). Similar results for systolic and diastolic BP were observed when assessing separately the effect of acute and chronic ingestion of ketone supplements (p ≥ 0.33). Supplement dosage was found to modulate the increase in resting heart rate (0.019 ± 0.006; p = 0.013; R2=100%), suggesting that higher supplement doses lead to a higher resting heart rate. Based on currently available data, acute or prolonged ingestion of ketone supplements does not seem to modulate BP. However, a tendency for HR to increase after acute ingestion was observed, particularly with higher doses. Higher quality studies with appropriate standardized measurements are needed to confirm these results. [ABSTRACT FROM AUTHOR]

Type 2 diabetes (T2D) is a complex and multifaceted condition clinically characterized by high blood glucose. The management of T2D requires a holistic approach, typically involving a combination of pharmacological interventions as well as lifestyle changes, such as incorporating regular exercise, within an overall patient-centred approach. However, several condition-specific and contextual factors can modulate the glucoregulatory response to acute or chronic exercise. In an era of precision medicine, optimizing exercise prescription in an effort to maximize glucose lowering effects holds promise for reducing the risk of T2D complications and improving the overall quality of life of individuals living with this condition. Reflecting on the main pathophysiological features of T2D, we review the evidence to highlight how factors related to exercise prescription can be modulated to target improved glucose control in T2D, including the frequency, intensity, total volume, and timing (e.g., pre- vs. post-prandial) of exercise, as well as exercise modality (e.g., aerobic vs. resistance training). We also propose a step-by-step, general framework for clinicians and practitioners on how to personalize exercise prescription to optimize glycemic control in individuals living with T2D. [ABSTRACT FROM AUTHOR]

BackgroundObesity and being overweight are major contributing factors for many diseases. Calorie restricted diets often fail to result in sustained long-term weight loss. Very low–carbohydrate, high-fat ketogenic diets have been suggested to have superior metabolic and weight loss effects. Keyto is a low-cost, highly scalable mobile health (mHealth) app paired with a noninvasive biofeedback tool aimed at facilitating weight loss through a personalized healthy and predominantly plant- and fish-based ketogenic diet. ObjectiveThis protocol describes a randomized trial comparing the efficacy of the Keyto mHealth app and device intervention to that of Weight Watchers’ WW app in individuals who are overweight or obese. The primary outcome is weight loss after 12 weeks. Secondary and exploratory outcomes, including metabolic and cardiovascular risk factors, will be assessed at 12, 24, and 48 weeks. MethodsA total of 144 participants will be recruited and randomized to either the Keyto program or Weight Watchers program. Study participants will be guided through the study via video conference or phone calls and will undergo a fasting blood analysis performed by a third-party diagnostic lab at weeks 0 and 12 to assess metabolic and cardiovascular risk markers. All participants will be asked to weigh themselves daily on a study-provided Bluetooth-enabled scale. Participants randomized to the Keyto arm will also be asked to measure their breath acetone levels, a measure of ketosis, with the Keyto device 3 times per day. ResultsRecruitment started in December 2019. Rolling recruitment is expected to be completed by July 2020. Data collection and analysis of the primary intervention phase is expected to be completed in October 2020. The 24- and 48-week follow-ups are expected to be completed in January 2021 and July 2021, respectively. ConclusionsThis trial will provide high-quality evidence regarding the efficacy of the Keyto weight loss program in individuals who are overweight and obese in a free-living condition. This study also fills a gap by examining the impact of a ketogenic diet emphasizing plant- and fish-based fats on blood lipid profile and cardiovascular disease risk. Trial RegistrationClinicalTrials.gov NCT04165707; https://clinicaltrials.gov/ct2/show/NCT04165707. International Registered Report Identifier (IRRID)DERR1-10.2196/19053