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Fasting is related to glucose intolerance and insulin resistance, but it is unknown whether the duration of fasting influences these factors. We explored whether prolonged fasting increases norepinephrine and ketone concentrations and decreases core temperature to a greater extent than short-term fasting; if so, this should lead to improved glucose tolerance. Forty-three healthy young adult males were randomly assigned to undergo a 2-d fast, 6-d fast or the usual diet. Changes in rectal temperature (TR), ketone and catecholamine concentrations, glucose tolerance and insulin release in response to an oral glucose tolerance test were assessed. Both fasting trials increased ketone concentration, and the effect was larger after the 6-d fast (P < 0·05). TR and epinephrine concentration increased only after the 2-d fast (P < 0·05). Both fasting trials increased the glucose area under the curve (AUC) (P < 0·05), but the AUC remained higher than the baseline value after participants returned to their usual diet in the 2-d fast group (P < 0·05). Neither fasting had an immediate effect on the insulin AUC, although it increased after return to their usual diet in the 6-d fast group (P < 0·05). These data suggest that the 2-d fast elicited residual impaired glucose tolerance, which may be linked to greater perceived stress during short-term fasting, as shown by the epinephrine response and change in core temperature. By contrast, prolonged fasting seemed to evoke an adaptive residual mechanism that is related to improved insulin release and maintained glucose tolerance. [ABSTRACT FROM AUTHOR]

The effect of globally recommended levels of physical activity on cognition andmotor behavior is not completely understood. Therefore, themain aim of this study was to assess the effect of 300 minutes per week of moderate-intensity aerobic exercise on cognitive and motor performance among overweight and obese working-age women. Methods: Overweight and obese participants aged 38-56 years were randomized to either a control or an experimental group performing aerobic exercise at 50% to 60% of the peak oxygen consumption for a 2-month period. Changes in aerobic fitness, cardiac autonomic function, brain-derived neurotropic factor levels, and cognitive and motor performance were assessed. Results: Although aerobic exercise reduced body weight (P < .05) and improved peak oxygen consumption (P < .05), the brain-derived neurotropic factor levels and cognitive and motor performance remained unchanged. Heart rate and blood pressure decreased (P < .05), whereas heart rate variability indices were not affected. No significant correlations between changes in heart rate variability indices and cognition were observed. Conclusions: Two months of moderate-intensity aerobic exercise decreased sympathetic activity and improved cardiovascular fitness but had no impact on cognition ormotor control among thesemiddle-aged, overweight, and obese women. [ABSTRACT FROM AUTHOR]

Background: The benefits of weight loss programs on mood, cognitive, and motor behavior are largely limited to those of calorie restriction or exercise alone. Our aim was to investigate the effect of combined calorie restriction and aerobic exercise intervention on mood, brain activity, and cognitive and motor behavior in overweight and obese women. Methods: Participants aged 36–56 years were randomized to either a control or an experimental group (aerobic exercise + 12.5% energy intake reduction) for a 6-month period. Changes in brain-derived neurotrophic factor levels, mood, prefrontal cortex activity, cognitive and motor performance were assessed. Results: Confusion and depression increased in the control group (P <.05), whereas tension decreased in the experimental group (P <.05). Brain-derived neurotrophic factor level and learning of a speed–accuracy task remained unchanged. Although prefrontal cortex activity and executive functions were not affected, the reaction time of visual scanning and associative learning were improved in the experimental group (P <.05). An improvement in reaction time during the speed–accuracy task was observed (P <.05). Conclusion: Combined calorie restriction and aerobic exercise intervention improved the psychosocial state, had little impact on cognition, and no effect on brain activity and learning of the speed–accuracy task. [ABSTRACT FROM AUTHOR]

Metabolites of the kynurenine (KYN) pathway of tryptophan (TRP) degradation have attracted interest as potential pathophysiological mediators and future diagnostic biomarkers. A greater knowledge of the pathological implications of the metabolites is associated with a need for a better understanding of how the normal behaviour and physiological activities impact their concentrations. This study aimed to investigate whether fasting (FAST) and whole-body cold-water immersion (CWI) affect KYN pathway metabolites. Thirteen young women were randomly assigned to receive the 2-d FAST with two 10-min CWI on separate days (FAST-CWI), 2-d FAST without CWI (FAST-CON), 2-d two CWI on separate days without FAST (CON-CWI) or the 2-d usual diet without CWI (CON-CON) in a randomised crossover fashion. Changes in plasma concentrations of TRP, kynurenic acid (KYNA), 3-hydroxy-kynurenine (3-HK), picolinic acid (PIC), quinolinic acid (QUIN) and nicotinamide (NAA) were determined with ultra-performance liquid chromatography-tandem mass spectrometer. FAST-CWI and FAST-CON lowered TRP concentration (P < 0·05, η p2 = 0·24), and increased concentrations of KYNA, 3-HK and PIC (P < 0·05, η p2 = 0·21–0·71) with no additional effects of CWI. The ratio of PIC/QUIN increased after FAST-CWI and FAST-CON trials (P < 0·05) but with a blunted effect in the FAST-CWI trial (P < 0·05) compared with the FAST-CON trials (η p2 = 0·67). Concentrations of QUIN and NAA were unaltered. This study demonstrated that fasting for 2 d considerably impacts the concentration of several metabolites in the KYN pathway. This should be considered when discussing the potential of KYN pathway metabolites as biomarkers. [ABSTRACT FROM AUTHOR]

Kinesiotaping (KT) is common in musculoskeletal rehabilitation, but whether it is efficacious for surgically untreated anterior cruciate ligament (ACL) ruptures is unknown. Therefore, we evaluated whether a strategy of physiotherapy plus KT would be superior to a strategy of physiotherapy alone on subsequent proprioception and motor function. Men aged 28.1 ± 6.7 years with complete ACL ruptures were randomized to either a control (physiotherapy) or an experimental group (physiotherapy + KT) for a 4-week period. Changes in balance were assessed on the injured leg using a force platform. Knee angle reproduction, maximal voluntary contraction (MVC), and rate of force development (RFD) were measured using dynamometry, and pain was recorded using a visual analog scale. Decreases in knee pain and improvements in angle reproduction were observed in both groups (p < 0.05), with a greater effect on angle reproduction in the experimental group (p < 0.05). Both groups demonstrated increased isometric knee flexor MVC and RFD values (p < 0.05), but an increase in RFD of the knee extensors was observed only in the experimental group (p < 0.05). Furthermore, the MVC of concentric knee flexors at 60°·s-1 increased only in the experimental group (p < 0.05), whereas concentric MVC at 180°·s-1-resulting in greater hamstring-to-quadriceps ratios-increased in both groups (p < 0.05). Balancing ability on the injured leg increased only in the experimental group (p < 0.05). Thus, KT plus physiotherapy was beneficial in the treatment of proprioception, strength, and static balance in these individuals with an ACL rupture. [ABSTRACT FROM AUTHOR]