Training Does Not Alter Muscle Ceramide and Diacylglycerol in Offsprings of Type 2 Diabetic Patients Despite Improved Insulin Sensitivity

Ceramide and diacylglycerol (DAG) may be involved in the early phase of insulin resistance but data are inconsistent in man. We evaluated if an increase in insulin sensitivity after endurance training was accompanied by changes in these lipids in skeletal muscle. Nineteen first-degree type 2 diabetes Offsprings (Offsprings) (age: 33.1±1.4 yrs; BMI: 26.4±0.4 kg/m2) and sixteen matched Controls (age: 31.3±1.5 yrs; BMI: 25.3±0.7 kg/m2) performed 10 weeks of endurance training three times a week at 70% of VO2max on a bicycle ergometer. Before and after the intervention a hyperinsulinemic-euglycemic clamp and VO2max test were performed and muscle biopsies obtained. Insulin sensitivity was significantly lower in Offsprings compared to control subjects (p<0.01) but improved in both groups after 10 weeks of endurance training (Off: 17±6%; Con: 12±9%, p<0.01). The content of muscle ceramide, DAG, and their subspecies were similar between groups and did not change in response to the endurance training except for an overall reduction in C22:0-Cer (p<0.05). Finally, the intervention induced an increase in AKT protein expression (Off: 27±11%; Con: 20±24%, p<0.05). This study showed no relation between insulin sensitivity and ceramide or DAG content suggesting that ceramide and DAG are not major players in the early phase of insulin resistance in human muscle

Aerobic exercise training increases muscle water content in obese middle-age men

Aerobic Exercise Training Increases Muscle Water Content in Obese Middle-Age Men. Med. Sci. Sports Exerc., Vol. 48, No. 5, pp. 00–00, 2016. Purpose: The objective of this study is to determine whether muscle water content (H2Omuscle) expands with training in deconditioned middle-age men and the effects of this expansion in other muscle metabolites. Methods: Eighteen obese (BMI = 33 T 3 kgImj2) untrained (V˙ O2peak = 29 T 7 mLj1Ikgj1Iminj1) metabolic syndrome men completed a 4-month aerobic cycling training program. Vastus lateralis muscle biopsies were collected before and 72 h after the completion of the last training bout. Water content, total protein, glycogen concentration, and citrate synthase activity were measured in biopsy tissue. Body composition was assessed using dual-energy X-ray absorptiometry, and cardiometabolic fitness was measured during an incremental cycling test. Results: Body weight and fat mass were reduced j1.9% and j5.4%, respectively (P G 0.05), whereas leg fat free mass increased with training (1.8%, P = 0.023). Cardiorespiratory fitness (i.e., V˙ O2peak), exercise maximal fat oxidation (i.e., FOmax), and maximal cycling power (i.e., Wmax) improved with training (11%, 33%, and 10%, respectively; P G 0.05). After 4 months of training, H2Omuscle increased from 783 T 18 to 799 T 24 gIkgj1 wet weight (ww) (2%, P = 0.011), whereas muscle protein concentration decreased 11% (145 T 15 to 129 T 13 gIkgj1 ww, P = 0.007). Citrate synthase activity (proxy for mitochondrial density) increased by 31% (17 T 5 to 22 T 5 mmolIminj1Ikgj1 ww, P = 0.024). Muscle glycogen concentration increased by 14% (22 T 7 to 25 T 7 gIkgj1 ww) although without reaching statistical significance when expressed as per kilogram of wet weight (P = 0.15). Conclusions: Our findings suggest that aerobic cycling training increases quadriceps muscle water although reduces muscle protein concentration in obese metabolic syndrome men. Reduced protein concentration coexists with increased leg lean mass suggestive of a water dilution effect that however does impair increased cycling leg power with training

Long-term fat diet adaptation effects on performance, training capacity, and fat utilization

Contains fulltext : mmubn000001_147077303.pdf (publisher's version ) (Open Access)Promotores : P. Calon en G. VerhaakXII, 251 p

Training affects muscle phospholipid fatty acid composition in humans

Cette étude vise à déterminer quel type d'entraînement exerce un effet sur la composition phospholipidique des acides gras du corps humain. 7 sujets masculins ont suivi pendant 4 semaines un entraînement spécifique des muscles extenseurs d'un genou, ceux de l'autre jambe restant inactifs. Une biopsie des muscles vastes externes est pratiquée avant, quatre jours après et à la fin des quatre semaines d'entraînement. Analyse et comparaison des résultat

Training affects muscle phospholipid fatty acid composition in humans

Cette étude vise à déterminer quel type d'entraînement exerce un effet sur la composition phospholipidique des acides gras du corps humain. 7 sujets masculins ont suivi pendant 4 semaines un entraînement spécifique des muscles extenseurs d'un genou, ceux de l'autre jambe restant inactifs. Une biopsie des muscles vastes externes est pratiquée avant, quatre jours après et à la fin des quatre semaines d'entraînement. Analyse et comparaison des résultat