Association between mitochondrial DNA haplogroups J and K, serum branched-chain amino acids and lowered capability for endurance exercise.

BACKGROUND: Endurance exercise training promotes the catabolism of branched-chain amino acids (BCAAs) in skeletal muscles. We have previously shown that mitochondrial DNA (mtDNA) haplogroups J and K are markers of low responders in endurance training. In this paper, we hypothesize that BCAA catabolism is a surrogate marker of lower respiratory chain activity attributed to these haplogroups. We evaluated whether exercise-induced changes in amino acid concentrations differ between subjects harbouring mtDNA haplogroups J or K and those with non-JK haplogroups. METHODS: Finnish male conscripts (N = 633) undertook the 12-min Cooper running test at the beginning and end of their military service. The intervention during the service mainly included endurance aerobic exercise and sports-related muscle training. Concentrations of seven amino acids were analysed in the serum using a high-throughput 1H NMR metabolomics platform. Total DNA was extracted from whole blood, and restriction fragment analysis was used to determine mtDNA haplogroups J and K. RESULTS: The concentrations of the seven amino acids were higher following the intervention, with the exception of phenylalanine; interestingly, the increase in the concentrations of three BCAAs was larger in subjects with haplogroup J or K than in subjects with non-JK haplogroups (p = 0.029). MtDNA haplogroups J and K share two common nonsynonymous variants. Structural analysis based on crystallographic data on bovine complexes I and III revealed that the Leu18 variant in cytochrome b encoded by m.14798T > C may interfere with ubiquinone binding at the Qi site in complex III. CONCLUSIONS: The increase in the concentrations of serum BCAAs following exercise intervention differs between subjects harbouring mtDNA haplogroup J or K and those harbouring non-JK haplogroups. Lower response in endurance training and difference in exercise-induced increase in the concentrations of serum BCAAs suggest decreased respiratory chain activity. Haplogroups J and K share m.14798T > C in MT-CYB, which may hamper the function of complex III.

Associations of increased physical performance and change in body composition with molecular pathways of heart disease and diabetes risk.

Higher physical activity is associated with a reduced hazard for a plethora of diseases. It has remained unknown how the two primary physical activity-associated health effects, improved physical performance and change in body composition, independently modulate metabolic profiles toward a reduced risk for adverse outcomes. Here, we utilized a prospective cohort of 664 young men undergoing military service. We studied the metabolic associations of changes in muscle performance and body composition during military service (range 6-12 mo). We subsequently replicated our results for body composition change in 234 population-based samples with a 7-yr follow-up. We found that increased physical performance was associated with reduced very-low-density lipoprotein (VLDL)-related measures [change in VLDL cholesterol: beta = -0.135; 95% confidence interval (CI) = -0.217, -0.054, P = 1.2 × 10-3] and lower inflammation (change in glycoprotein acetyls: beta = -0.138, 95% CI = -0.217, -0.059, P = 6.5 × 10-4), independent of change in body composition. Lower body fat percentage, independent of change in muscle performance, was associated with metabolic changes including lower low-density lipoprotein (LDL) cholesterol measures (change in LDL cholesterol: beta = -0.193, 95% CI = -0.295, -0.090; P = 2.5 × 10-4), increased high-density lipoprotein (HDL) cholesterol measures (change in large HDL cholesterol: beta = 0.316, 95% CI = 0.205, 0.427; P = 3.7 × 10-8), and decreased concentrations of amino acids (change in leucine concentration: beta = -0.236, 95% CI = -0.341, -0.132; P = 1.0 × 10-5) that are type 2 diabetes biomarkers. Importantly, all body fat percentage associations were replicated in a general population-based cohort. Our findings indicate that improved muscle performance showed weaker associations on the metabolic profiles than change in body composition and reduction in body fat percentage reduces cardiometabolic risk mediated by atherogenic lipoprotein particles and branched-chain and aromatic amino acid concentrations.

Effective Weight Loss and Maintenance by Intensive Start with Diet and Exercise.

INTRODUCTION: This 24-month study aimed to determine whether exercise intervention added to weight loss treatment at 6 months is effective for weight loss and maintenance. METHODS: A total of 120 obese subjects (body mass index > 30) were randomly assigned to intensified behavioral modification (iBM) (n = 30), behavioral modification + exercise from 0 to 3 months (circuit weight training group 1 [CWT1]) (n = 30), behavioral modification + exercise from 6 to 9 months (CWT2) (n = 30), and a control group (CON) (n = 30). Health behavior, weight, waist circumference, and 2-h glucose tolerance test with insulin measurements were measured at 0, 3, 9, and 24 months. RESULTS: Eighty-five subjects (mean age = 46 yr, body mass index = 36.3, 75.3% women) completed the trial. A significant weight loss occurred in CWT1 (-8.5 kg, P > 0.001), iBM (-5.5 kg, P > 0.001), and CWT2 (-4.4 kg, P = 0.007). CWT1 showed the highest reduction in waist circumference at 9 months (mean difference = -11.5 cm, P < 0.001) and 24 months (mean difference = -8.8 cm, P < 0.001). Both fasting and 2-h insulin values improved in the intervention groups compared with CON. A significant decrease in 2-h insulin values from baseline was found in CWT1 and CWT2. Matsuda index improved in the CWT1 group from the baseline to 24 months (2.03, P = 0.025). CONCLUSION: The most effective weight loss regimen is a combination of iBM and weight training introduced from the very beginning of the weight loss period. Treatment of morbid obesity should include an intensive start with exercise and diet regardless of weight status.

Physical activity and body composition changes during military service.

PURPOSE: To examine how body composition changes in different body mass index (BMI) categories among young Finnish men during military service, which is associated with marked changes in diet and physical activity. In addition, this study examined how reported previous physical activity affected the body composition changes. METHODS: Altogether 1003 men (19 yr) were followed throughout their military service (6-12 months). Height, weight, BMI, waist circumference, and waist-to-hip ratio (WHR) were recorded. Previous physical activity was assessed at the beginning of the service by a questionnaire. Body composition was measured by bioelectrical impedance assessments (BIA) at the beginning and at the end of the service. The measured parameters were fat mass (FM), fat percentage (fat %), fat-free mass (FFM), visceral fat area (VFA), lean body mass (LBM), and skeletal muscle mass (SMM). RESULTS: On average, military training decreased weight by 0.7%, FM by 9.7%, fat % by 6.6%, and VFA by 43.4%. FFM increased by 1.3%, LBM by 1.2%, and SMM by 1.7%. The group of underweight and normal-weight men gained weight, FM, and FFM, whereas overweight and obese men lost weight and FM and gained FFM. FM was most reduced in the groups of overweight (20.8%) and obese (24.9%) men. The amount of VFA was reduced in all BMI groups (38%-44%). Among overweight men who reported being inactive previous to the military service, more beneficial changes in body composition were observed compared with those who reported being physically active. CONCLUSIONS: The lifestyle changes associated with military service markedly reduce fat tissue and increase the amount of lean tissue. These beneficial changes are prominent among previously inactive subjects with high BMI.