Stand up to excite the spine : neuromuscular, autonomic, and cardiometabolic responses during motor imagery in standing vs. sitting posture

Motor imagery (MI) for health and performance strategies has gained interest in recent decades. Nevertheless, there are still no studies that have comprehensively investigated the physiological responses during MI, and no one questions the influence of low-level contraction on these responses. Thus, the aim of the present study was to investigate the neuromuscular, autonomic nervous system (ANS), and cardiometabolic changes associated with an acute bout of MI practice in sitting and standing condition. Twelve young healthy males (26.3 % 4.4 years) participated in two experimental sessions (control vs. MI) consisting of two postural conditions (sitting vs. standing). ANS, hemodynamic and respiratory parameters, body sway parameters, and electromyography activity were continuously recorded, while neuromuscular parameters were recorded on the right triceps surae muscles before and after performing the postural conditions. While MI showed no effect on ANS, the standing posture increased the indices of sympathetic system activity and decreased those of the parasympathetic system (p < 0.05). Moreover, MI during standing induced greater spinal excitability compared to sitting posture (p < 0.05), which was accompanied with greater oxygen consumption, energy expenditure, ventilation, and lower cardiac output (p < 0.05). Asking individuals to perform MI of an isometric contraction while standing allows them to mentally focus on the motor command, not challenge balance, and produce specific cardiometabolic responses. Therefore, these results provide further evidence of posture and MI-related modulation of spinal excitability with additional autonomic and cardiometabolic responses in healthy young men

Physiological Pattern Changes in Response to a Simulated Competition in Elite Women's Artistic Gymnasts

International audienc

Effects of exercise training on muscle mass and physical function in patients with hepatocellular carcinoma after diagnosis: a systematic review

Background & Aims: Decreased muscle mass and physical function are common complications in hepatocellular carcinoma (HCC) patients which are associated with increased morbidity and mortality. Thus, there have been targeted efforts to prevent and/or improve both by enrolling these patients in exercise training programs. We performed a systematic review to evaluate the effects of exercise training on muscle mass and physical function in people with HCC after diagnosis. Methods: A systematic literature search was conducted using the Medline, Base, PubMed, Cochrane and Scopus, and trial registries, through April 2023 for studies that assessed the effects of an exercise training program in adults with HCC. The primary outcomes were muscle mass and physical function. To assess the risk of bias, we used the Quality Assessment Tool for Quantitative Studies from the Effective Public Health Practice Project. Results: Eight studies met inclusion criteria, comprising a total of 809 participants. Interventions included aerobic exercise training, resistance exercise training, balance and flexibility training, or home-based exercise training. Four studies showed statistically significant improvements in at least one muscular outcome. Three studies showed a maintenance of muscular outcomes, and one a decrease in muscle mass. Four articles showed statistically improvements in at least one physical fitness variable, two showed a maintenance of physical function variable. Conclusion: Together the results suggest that patients may benefit from physical exercise training after treatment to improve muscle mass and physical function.</p

Voluntary exercise fails to prevent metabolic dysfunction-associated steatotic liver disease progression in male rats fed a high-fat high-cholesterol diet

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a major public health issue with a worldwide prevalence of 30%–32%. In animal models, voluntary exercise may be an alternative to forced physical activity, avoiding stress, potential injuries, and being logistically simpler. Here, we assessed voluntary exercise (Vex) in Sprague–Dawley rats fed a high-fat, high-cholesterol diet for 18 weeks to induce MASLD. We quantified workload (speed and distance) using exercise wheels and evaluated energy expenditure using calorimetric cages. MASLD progression was assessed using circulating and hepatic biochemical and gene markers of steatosis, inflammation, and fibrosis. The animals ran an average of 301 km during the study period, with the average daily distance peaking at 4937 m/day during Weeks 3–4 before decreasing to 757 m/day by the end of the study. Rats exposed to Vex showed no improvement in any of the MASLD-associated features, such as steatosis, inflammation, or fibrosis. Rats exposed to Vex exhibited a higher total energy expenditure during the night phase (+0.35 kcal/h; p = 0.003) without resulting in any effect on body composition. We conclude that, in our experimental conditions, Vex failed to prevent MASLD progression in male Sprague–Dawley rats exposed to a high-fat high-cholesterol diet for 18 weeks.</p

The hepatokine leukocyte cell-derived chemotaxin-2 is elevated in people with impaired glycaemic control and augmented by acute exercise [Abstract]

Conference abstract presented at EASL SLD (Steatotic Liver Disease) Summit 2023.</p

The hepatokine leukocyte cell-derived chemotaxin-2 is elevated in people with impaired glycaemic regulation and augmented by acute exercise

The hepatokine leukocyte cell-derived chemotaxin-2 (LECT2) promotes insulin resistance and hepatic fibrogenesis. In rodents, acute exercise suppresses circulating LECT2; however, human data are lacking. This study compared circulating LECT2 across populations and explored whether acute exercise impacts circulating LECT2. In Part A (n = 43), data were pooled from three experimental studies, regarding the following groups: healthy individuals, individuals with impaired glycaemic regulation (IGR), and individuals with type 2 diabetes and metabolic dysfunction-associated steatotic liver disease (T2DM-MASLD). Generalised linear models assessed differences in circulating LECT2 among groups. Part B (n = 20) involved exercise (30 min, 65% peak oxygen uptake) and control (resting) trials in the healthy and IGR groups. Circulating LECT2 was measured before and at 0, 1, 2 and 3 h post-exercise. Generalised estimating equations assessed differences in LECT2 responses to the trials among groups. In Part A, circulating LECT2 levels were 28.7% and 37.3% higher in the IGR and T2DM-MASLD groups, vs. healthy individuals (p ≤ 0.038), with BMI identified as the main predictor (p = 0.008). In Part B, average circulating LECT2 levels were 6.3% higher after exercise vs. in the control (p p = 0.829). In the combined cohort, circulating LECT2 levels were elevated 1–3 h after exercise vs. control (p ≤ 0.009). LECT2 is elevated in people with dysglycaemia, with BMI as a leading predictor. Contrary to previous rodent work, acute exercise augments, rather than suppresses, circulating LECT2 in humans. </p

The impact of six weeks of moderate-intensity exercise training on circulating hepatokine concentrations in men with MASLD and impaired glycaemic regulation [Abstract]

This is a conference paper abstract.</p

Association between alanine aminotransferase as surrogate of fatty liver disease and physical activity and sedentary time in adolescents with obesity

International audienceTo compare patterns of sedentary (SED) time (more sedentary, SED + vs less sedentary, SED-), moderate to vigorous physical activity (MVPA) time (more active, MVPA + vs less active, MVPA-), and combinations of behaviors (SED-/MVPA + , SED-/MVPA-, SED + /MVPA + , SED + /MVPA-) regarding nonalcoholic fatty liver diseases (NAFLD) markers. This cross-sectional study included 134 subjects (13.4 +/- 2.2 years, body mass index (BMI) 98.9 +/- 0.7 percentile, 48.5% females) who underwent 24-h/7-day accelerometry, anthropometric, and biochemical markers (alanine aminotransferase (ALT) as first criterion, and aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), AST/ALT ratio as secondary criteria). A subgroup of 39 patients underwent magnetic resonance imaging-liver fat content (MRI-LFC). Hepatic health was better in SED- (lower ALT, GGT, and MRI-LFC (p < 0.05), higher AST/ALT (p < 0.01)) vs SED + and in MVPA + (lower ALT (p < 0.05), higher AST/ALT (p < 0.01)) vs MVPA- groups after adjustment for age, gender, and Tanner stages. SED-/MVPA + group had the best hepatic health. SED-/MVPA- group had lower ALT and GGT and higher AST/ALT (p < 0.05) in comparison with SED + /MVPA + group independently of BMI. SED time was positively associated with biochemical (high ALT, low AST/ALT ratio) and imaging (high MRI-LFC) markers independently of MVPA. MVPA time was associated with biochemical markers (low ALT, high AST/ALT) but these associations were no longer significant after adjustment for SED time

Greater hepatic lipid saturation is associated with impaired glycaemic regulation in men with MASLD but is not altered by six weeks of exercise training

Aims To examine the impact of impaired glycaemic regulation and exercise training on hepatic lipid composition in men with metabolic dysfunction-associated steatotic liver disease (MASLD).  Materials and methods In Part A (cross-sectional design), 40 men with MASLD (liver proton density fat fraction [PDFF]≥5.56%) were recruited to one-of-two groups: 1) normal glycaemic regulation (NGR; HbA1c Results In Part A, hepatic SI was higher and hepatic UI was lower in the IGR vs. NGR group (P=0.038), and this hepatic lipid profile was associated with higher HbA1c, FPG, HOMA-IR and plasma CK18 M65 (rs≥0.320). In Part B, hepatic lipid composition and liver PDFF were unchanged after EX vs. CON (P≥0.257), while FPG was reduced and V̇O2 peak was increased (P≤0.030). ΔV̇O2 peak was inversely associated with Δhepatic SI (r=-0.433) and positively associated with Δhepatic UI and Δhepatic PUI (r≥0.433).  Conclusions IGR in MASLD is characterised by greater hepatic lipid saturation, however, this composition is not altered by six-weeks of moderate-intensity exercise training. ClinicalTrials.gov: NCT04004273</div