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Resistance training (RT) promotes skeletal muscle (Skm) hypertrophy, increases muscular strength, and improves metabolic health. Whether changes in fat-free mass (FFM; a surrogate marker of muscle hypertrophy) moderate RT-induced improvements in glucose homeostasis has not been determined, despite extensive research on the benefits of RT for health and performance. The aim of this meta-analysis is to examine whether RT-induced Skm hypertrophy drives improvements in glucose metabolism and to explore confounders, such as biological sex and training parameters. Random-effects meta-analyses were performed using variance random effects. Meta-regressions were performed for confounding factors depending on the heterogeneity (I2). Analyses from 33 intervention studies revealed significant within-study increases in FFM with a moderate effect size (within-studies: (effect size; ES = 0.24 [0.10; 0.39]; p = 0.002; I2 = 56%) and a tendency for significance when compared with control groups (ES = 0.42 [−0.04–0.88]; p = 0.07). Within-study significant increases in glucose tolerance (2 h glucose: ES = −0.3 [−0.50; −0.11]; p < 0.01; I2 = 43%; glucose area under the curve (AUC): −0.40 [−0.66; −0.13] I2 = 76.1%; p < 0.01) and insulin sensitivity (ES = 0.38 [0.13; 0.62]; I2 = 53.0%; p < 0.01) were also apparent with RT. When compared to control groups, there was no significant difference in 2 h glucose, nor in glucose AUC from baseline in RT intervention groups. Meta-regression analyses failed to consistently reveal increases in FFM as a moderator of glucose homeostasis. Other mixed-effect models were also unsuccessful to unveil biological sex or training parameters as moderators of FFM increases and glucose homeostasis changes. Although Skm hypertrophy and improvements in glycemic control occur concurrently during RT, changes in these variables were not always related. Well-controlled trials including detailed description of training parameters are needed to inform RT guidelines for improving metabolic health. Registration and protocol number (Prospero): CRD42023397362. [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]

Two high-intensity interval training (HIIT) regimens are often used in research and clinical settings. Yet, there has been no direct comparison to determine if one can improve glucose control and variability to a greater extent in individuals living with type 2 diabetes (T2D). Fourteen older females with T2D participated in a semi-randomized control trial where HIIT10 (10 × 1-min intervals at 90% heart rate max; HRmax) and HIIT4 (4 × 4-min intervals at 90% of HRmax) were compared to a control condition (CON; no exercise). Continuous glucose monitoring was used to assess glucose control and variability over 24 h after each condition. Both HIIT10 (−2.1 ± 1.1 mmol/L) and HIIT4 (−2.1 ± 1.3 mmol/L) acutely lowered glucose compared to CON (−0.7 ± 0.8 mmol/L; p = 0.001), with no difference between exercise conditions. This glucose-lowering effect did not persist over the 24-h post-exercise period, as both mean glucose (p = 0.751) and glucose variability (p = 0.168) were not significantly different among conditions. However, exploratory analyses focusing on individuals with less optimal glucose control (above median 24-h mean glucose in the CON condition; n = 7) revealed that 24-h mean glucose (7.4 [7.14–8.92] vs. 8.4 [7.5–9.9] mmol/L; p = 0.048), glucose variability (p = 0.010), and peak glucose (p = 0.048) were lower following HIIT10 compared to CON, while HIIT4 reduced time spent in moderate hyperglycemia compared to CON (p = 0.023). Both HIIT10 and HIIT4 acutely lower glycemia, but the effect does not persist over 24 h. However, in individuals with worse glucose control, HIIT10 may improve mean 24-h glucose and glycemic variability, while HIIT4 may reduce time spent in moderate hyperglycemia. [ABSTRACT FROM AUTHOR]

In the workplace, people are often sedentary for prolonged time and do not regularly engage in physical activity—two factors independently linked to premature morbidity and mortality. This study aimed to determine the receptivity of incorporating practical stair-climbing "exercise snacks" (Snacks; three isolated bouts of ascending 53–60 stairs performed sporadically throughout the day) into workplace settings compared to more traditional high-intensity interval training (HIIT; performed as three bouts of 53-60 stairs within a structured HIIT workout) and to explore if these exercise strategies could influence sedentary and physical activity behaviour. Fourteen participants (12 women; Mage = 38.9 ± 10.2 years) completed two supervised exercise trials (Snacks and HIIT) followed by 1 week participating in either form of exercise in their workplace. Ratings of perceived exertion (RPE), affective valence, enjoyment, and self-efficacy were measured at the supervised exercise sessions. During the follow-up period, sedentary behaviour and physical activity were measured with an accelerometer. Affective valence was more positive (p = 0.03; η2p = 0.21) and there was a lower rise in RPE (p = 0.01; η2p = 0.29) during Snacks than HIIT. Post-exercise enjoyment of, and self-efficacy towards, Snacks and HIIT were high and similar (ps > 0.05). After the supervised trials, 10/14 of the participants preferred Snacks and 4/14 preferred HIIT (p = 0.18). On days when participants chose to perform either exercise modality, the average number of sit-to-stands in a 24 h period was increased (48.3 ± 8.7 to 52.8 ± 7.8; p = 0.03; Hedge's g = 0.73) and moderate-to-vigorous physical activity tended to increase (21.9 ± 18.2 to 38.1 ± 22.1 min; p = 0.06; Hedge's g = 0.60) compared to days when they chose not to exercise. Stair-climbing exercise snacks may be an attractive approach to implement in the workplace setting and has potential to positively impact sedentary behaviour and physical activity metrics. [ABSTRACT FROM AUTHOR]