BackgroundHigh intensity exercise is considered as an effective means for reducing body fat. The aims of the present study were to investigate (1) whether body mass would be lost and body composition would change and (2) whether variables of anaerobic fitness prior to the intervention period would be related to loss of body mass and changes in body composition in overweight and obese children and adolescents.MethodsA total of 28 children and adolescents (19 boys, 9 girls) attended an 8-week multicomponent inpatient program. Caloric intake was based on the subject’s weight and a daily energy deficit of ~500 kcal was targeted. At the beginning and at the end of the program, variables of anaerobic fitness were assessed using Wingate tests. Body composition was measured before and after the program using dual-energy X-ray absorptiometry.ResultsBody mass decreased by 11.4% ± 1.6% in boys and by 11.0% ± 2.8% in girls (P < 0.001). Fat mass decreased by 23.8% ± 6.1% in boys and by 21.5% ± 5.2% in girls (P < 0.001). The decrease in fat mass was associated with the decrease in body mass in boys (r = 0.54, P = 0.017) but not in girls (P > 0.05). The decrease in body mass and the decrease in fat mass were neither associated with overall energy expenditure nor with the energy deficit in both genders (P > 0.05). Mean power in W/kg increased in the Wingate tests by 95.4% ± 109.1% in boys and by 100.0% ± 119.9% in girls (P < 0.001).ConclusionsAdjustments of the chronically positive imbalance of energy intake and energy expenditure of obese children and adolescents living in obesogenic environments should be addressed in a multisectoral approach. Future research in multicomponent childhood and adolescent weight loss programs should be directed towards a better understanding of the underlying complex dynamics in energy homeostasis which promote weight loss and changes in body composition due to high intensity exercise interventions.

Exercise in water compared to land-based exercise (LE) results in a higher release of natriuretic peptides, which are involved in the regulation of exercise-induced adipose tissue lipolysis. The present study was performed to compare the release of atrial natriuretic peptide (ANP) and free fatty acids (FFA) during prolonged aerobic water-based exercise (WE) with the release after an identical LE. 14 untrained overweight subjects performed 2 steady state workload tests on the same ergometer in water and on land. Before and after exercise, venous blood samples were collected for measuring ANP, FFA, epinephrine, norepinephrine, insulin and glucose. The respiratory exchange ratio (RER) was determined for fat oxidation.The exercises resulted in a significant increase in ANP in LE (61%) and in WE (177%), and FFA increased about 3-fold in LE and WE with no significant difference between the groups. Epinephrine increased, while insulin decreased similarly in both groups. The RER values decreased during the exercises, but there was no significant difference between LE and WE. In conclusion, the higher ANP concentrations in WE had no additional effect on lipid mobilization, FFA release and fat oxidation. Moderate-intensity exercises in water offer no benefit regarding adipose tissue lipolysis in comparison to LE.

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Hemiplegie [ 4 ] , bei amputierten unteren Gliedmassen [ 5 ] und Multiple Sklerose [ 6 ] werden kardiopulmonale Reaktionen verstärkt, wenn die Arbeit mit Armen und Beinen auf einem geeigneten Ergometer durchgeführt wird.

BackgroundAtrial natriuretic peptides (ANP) and Brain natriuretic peptides (BNP) stimulate fat cell plasma membrane receptors. They are potent lipolytic agents on isolated fat cells from subcutaneous adipose tissue. The physiological effects of continuous endurance exercise on ANP release and plasma free fatty acids (FFA) concentrations have been well described. The enhancement of fat metabolism using high intensity intermittent exercise protocols has been assessed in more recent investigations. The combined effects of endurance exercise and water immersion on ANP and FFA plasma concentration and the magnitude of excess post-exercise oxygen consumption (EPOC) might be further enhanced by choosing the most effective exercise protocol. Exercise modalities may play a significant role in the future prevention and treatment of obesity.Methods/designThe two testing trials will be performed according to a randomized and cross-over design. Twenty healthy sedentary pre-obese and obese class-1 men will be scrutinized with regard to their metabolic responses to continuous exercise in water and to high intensity endurance exercise in water. Both trials will be matched for energy expenditure. After preliminary testing, the tests will be conducted as repeated measurements. The two different exercise protocols will be compared. The aims of the study are to investigate (1) whether continuous endurance exercise or high intensity intermittent endurance exercise in water elicits both a higher release of ANP and BNP and a higher plasma concentration of glycerol and (2) to determine whether continuous endurance exercise in water or a high intensity intermittent endurance exercise in water would lead to a more pronounced short term (two hours) EPOC effect.DiscussionIf our hypothesis would be confirmed, the most effective exercise protocol based on the combined effects of high intensity endurance exercise and water immersion on ANP and BNP release and glycerol plasma concentrations can be identified. Moreover, the magnitude of the EPOC effect can be augmented. Our study would provide a major contribution for creating optimized exercise modalities in the prevention and treatment of obesity.Trial registrationCurrent controlled trials, ISRCTN95488515