Different Effects of Cyclical Ketogenic vs. Nutritionally Balanced Reduction Diet on Serum Concentrations of Myokines in Healthy Young Males Undergoing Combined Resistance/Aerobic Training.

Myokines represent important regulators of muscle metabolism. Our study aimed to explore the effects of a cyclical ketogenic reduction diet (CKD) vs. a nutritionally balanced reduction diet (RD) combined with regular resistance/aerobic training in healthy young males on serum concentrations of myokines and their potential role in changes in physical fitness. Twenty-five subjects undergoing regular resistance/aerobic training were randomized to the CKD (n = 13) or RD (n = 12) groups. Anthropometric and spiroergometric parameters, muscle strength, biochemical parameters, and serum concentrations of myokines and cytokines were assessed at baseline and after 8 weeks of intervention. Both diets reduced body weight, body fat, and BMI. Muscle strength and endurance performance were improved only by RD. Increased musclin (32.9 pg/mL vs. 74.5 pg/mL, p = 0.028) and decreased osteonectin levels (562 pg/mL vs. 511 pg/mL, p = 0.023) were observed in RD but not in the CKD group. In contrast, decreased levels of FGF21 (181 pg/mL vs. 86.4 pg/mL, p = 0.003) were found in the CKD group only. Other tested myokines and cytokines were not significantly affected by the intervention. Our data suggest that changes in systemic osteonectin and musclin levels could contribute to improved muscle strength and endurance performance and partially explain the differential effects of CKD and RD on physical fitness.

The Influence of Cyclical Ketogenic Reduction Diet vs. Nutritionally Balanced Reduction Diet on Body Composition, Strength, and Endurance Performance in Healthy Young Males: A Randomized Controlled Trial.

(1) Background: The influence of ketogenic diet on physical fitness remains controversial. We performed a randomized controlled trial to compare the effect of cyclical ketogenic reduction diet (CKD) vs. nutritionally balanced reduction diet (RD) on body composition, muscle strength, and endurance performance. (2) Methods: 25 healthy young males undergoing regular resistance training combined with aerobic training were randomized to CKD (n = 13) or RD (n = 12). Body composition, muscle strength and spiroergometric parameters were measured at baseline and after eight weeks of intervention. (3) Results: Both CKD and RD decreased body weight, body fat, and BMI. Lean body mass and body water decreased in CKD and did not significantly change in RD group. Muscle strength parameters were not affected in CKD while in RD group lat pull-down and leg press values increased. Similarly, endurance performance was not changed in CKD group while in RD group peak workload and peak oxygen uptake increased. (4) Conclusions: Our data show that in healthy young males undergoing resistance and aerobic training comparable weight reduction were achieved by CKD and RD. In RD group; improved muscle strength and endurance performance was noted relative to neutral effect of CKD that also slightly reduced lean body mass.

Aerobic exercise has beneficial impact on atherogenic index of plasma in sedentary overweigh and obese women.

OBJECTIVE: In obese patients, we hypothesized physical exercise (PE) to affect lipids through its intrahepatic fat accumulation-lowering effect, associated with a decrease of total body fat (Fat%) and even weight (Mass). DESIGN AND SETTING: Thirty seven sedentary, non-diabetic women (BMI median 34.8) from our out-patient department were tested. Elimination criteria: recent weight reduction, lipid-influencing or heart rate-modifying medication. PARTICIPANTS: 50 entering, 37 finishing, 7 excluded for processing failure, 6 did not fulfill the protocol. INTERVENTIONS: PE protocol: 60 min supervised trainings, intensity at 65% of VO2max, modified by the clamp heart rate test. Median of total training hours was 34 during 115 days (median). MAIN OUTCOME MEASUREMENTS: an effect of PE on total cholesterol (CH), triglycerides (TG), HDL-cholesterol (HDL_C), LDL-cholesterol (LDL_C), index of atherogenity (IA), atherogenic index of plasma (AIP), maximum peak oxygen consumption (VO2max), Mass, body mass index (BMI), waist circumference (Waist) and Fat%. RESULTS: Statistically significant differences at start (_s) and the end (_e) of PE (p<0.05): AIP -0.049, Mass -3.6 (kg), BMI -1.7 (kg/m2), Waist -2.5 (cm), Fat% -2.5, VO2max 2.92 (L.min-1kg-1). Correlation coefficients, Pearson's between Gaussian distributed (Gd-v) variables and Spearman´s (non Gd-v) statistically significant (p<0.05): IA and BMI, IA and Mass, IA and Waist, IA and Fat%, LDL and BMI, LDL and Mass, LDL and Fat%, LDL and Waist, IA and VO2max, LDL_C and VO2max. CONCLUSIONS: PE improves lipid profile towards production of antiatherogenic particles more likely due to changes in anthropometric parameters than in improvement of physical fitness.

Cardiac structural and functional changes in competitive amateur cyclists.

PURPOSE: To assess cardiac structural and functional changes induced by competitive amateur cycling. METHODS: Fifty-one young competitive amateur male cyclists and 47 age- and gender-matched control subjects underwent complex transthoracic echocardiographic examination focused on the detailed assessment of cardiac size and function, especially of the left ventricle (LV). Subsequently, spiroergometry was performed in all study participants and its results were compared to echocardiographic data. RESULTS: Higher left ventricular mass indexes due to the greater LV wall thickness and LV end-diastolic diameter were found in amateur cyclists as compared to control subjects. There were no differences with regard to the LV systolic function parameters. However, significantly better indices of LV diastolic function were present in cyclists. A significant correlation between maximal oxygen pulse and LV mass index/height(2.7), LV diastolic parameters and right ventricular size was noted. CONCLUSIONS: Amateur competitive cycling leads to considerable LV structural and functional changes. The increases in LV wall thickness and cavity size together with supranormal diastolic properties are key characteristics of this LV remodeling. As well, LV mass, diastolic function, and RV size are predictors of exercise capacity, indicating an important involvement of these elements in improving cardiac function with endurance training.