Prefrontal Cortex Oxygenation During Exercise in Older Adults with Motoric Cognitive Risk Syndrome.

Motoric cognitive risk syndrome (MCR) is a pre-dementia syndrome characterized by subjective memory complaints and gait impairments that may be related to lower prefrontal cortex (PFC) function. Acute bouts of aerobic exercise are shown to improve PFC function, however, the acute effects of exercise on PFC oxygenation have not yet been examined in MCR. This study aims to characterize the PFC oxygenation responses during acute exercise in older adults with MCR. Nineteen older adults with MCR performed a submaximal cycling exercise protocol. Functional near-infrared spectroscopy (fNIRS) is used to measure concentrations of oxygenated (OxyHb) and deoxygenated (DeoxyHb) hemoglobin from the PFC. There is a trend for increased OxyHb concentrations and decreased DeooxyHb concentrations during exercise. Exercise also induced significant increases in ratings of perceived exertion (RPEs) and heart rate. A significant, positive correlation between PFC OxyHb and RPEs during the cycling exercise are also observed. The findings reveal that PFC oxygenation increases during exercise in an intensity-dependent manner and the subjective perception of exertion is associated with the magnitude of PFC oxygenation. These results suggest that moderate-intensity cycling exercise may have beneficial effects on increasing cerebral blood flow in the PFC of older adults with MCR.

Systolic blood pressure mediates the association between body mass index and inhibitory control in children.

Here, we examine whether systolic blood pressure (SBP) mediates the relationship between body mass index (BMI) and inhibitory control in children. Twenty children with high blood pressure (HBP) were approximately matched with twenty children with low blood pressure (LBP) by fitness, BMI, somatic maturation, sex and age. Inhibitory control was measured by a cognitive Go/Nogo task, where number of commission errors during Nogo trials and reaction time during Go trials were used as performance. We compared performance between the two groups and conducted a mediation analysis using SBP as mediator of the relationship between BMI and commission errors. Results revealed that HBP children presented higher number of commission errors, compared to LBP children. Moreover, SBP mediated the relation between BMI and number of errors. Thus, early exposure to high levels of SBP can negatively impact inhibitory control and SBP acts as a mediator between BMI and inhibitory functioning in children.

Phase angle is associated with cardiorespiratory fitness and body composition in children aged between 9 and 11 years.

Phase angle (PhA) is a marker of health and cellular integrity and is used as a tool for predicting nutritional status in children with various health conditions. Even though physical activity and cardiorespiratory fitness have been shown to provide several health benefits, few studies have evaluated the relationship between PhA and health parameters, i.e., cardiorespiratory fitness and body composition. Thus, we aimed to evaluate the association between PhA and cardiorespiratory fitness in children aged between 9 and 11 years. Twenty-three children (52% girls) were tested in a cross-sectional study. The PhA was calculated by bioelectric impedance parameters. Body fat (BF) and fat-free mass (FFM) were measured by dual-energy absorptiometry. Cardiorespiratory fitness (VO2 peak) was performed using the 20-meter shuttle-run test, and allometric scaling were calculated to better control the effect of body weight (VO2 peak BW), BF (VO2 peak BF) and FFM (VO2 peak FFM) on fitness. All analyses were performed separately for each sex group. Pearson's correlation was used to test the association between PhA, cardiorespiratory fitness (relative and absolute), and body composition [BF (kg and%) and FFM]. Linear regression analysis was used to test the determinant effect of cardiorespiratory fitness values on PhA. In girls, the PhA was negatively associated with%BF (r = -0.66), and positively associated with FFM (r = 0.68), VO2 peak BW (r = 0.69), and VO2 peak FFM (r = 0.78). While in boys, the PhA was positively associated with VO2 peak BW (r = 0.71), VO2 peak BF (r = 0.75), and VO2 peak FFM (r = 0.70). Linear regression showed an association of VO2 peak FFM on PhA in girls and boys (ß = 0.781 and ß = 0.703, respectively), and an association of VO2 peak BW and VO2 peak BF on PhA only in boys (ß = 0.705 and ß = 0.746, respectively). We concluded that PhA was negatively associated with %BF and positively associated with FFM in girls. Furthermore, when allometric scaling was used to better control the effect of body weight, body fat and fat-free mass, the PhA was positive associated with VO2 peak BW, VO2 peak FFM (in girls and boys), and VO2 peak BF in boys. These results suggest that the value of phase angle can be an important parameter to investigate health status related to body composition and cardiorespiratory fitness in children.

Cardiorespiratory Fitness Predicts Greater Vagal Autonomic Activity in Drug Users Under Stress.

While drug use has been shown to impair cardiac autonomic regulation, exercise might overcome some of the damage. Herein, we describe how individuals with substance use disorder (SUD) have their heart rate variability (HRV) and drug-related behaviors negatively affected in response to a stressor. However, we show how cardiorespiratory fitness may attenuate those impairments in autonomic control. Fifteen individuals with SUD were matched with 15 non-SUD individuals by age, weight, height, and fitness level, and had their HRV responses under stress induced by the Cold Pressor Test (CPT). The SUD group had lower mean of R-R intervals before and after the CPT when compared with the non-SUD group. In addition, in individuals with SUD, higher cardiorespiratory fitness level predicted greater vagal activity before, during, and after CPT. Moreover, for individuals with SUD, days of abstinence predicted greater mean of R-R intervals during recovery from the CPT. Finally, years of drug use negatively predicted mean of R-R intervals during recovery. Thus, our results suggest that chronic drug use impairs cardiac autonomic regulation at rest and after a physical stress. However, cardiorespiratory fitness might attenuate these impairments by increasing vagal autonomic activity.

Fat mass predicts food-specific inhibitory control in children.

BACKGROUND/OBJECTIVES: Impaired inhibitory control has been associated with obesity, high blood pressure and lack of physical fitness. These impairments are thought to be related to decreased cognitive control over excessive food consumption and may start in childhood. However, previous studies in children have examined inhibitory control deficits using general (non-food-specific) tasks and relied on body mass index, which does not distinguish the amount of fat mass. As fat mass, hypertension and physical fitness have been shown to play a role in cognition, the aim of this study was to investigate the relationship between these variables and food specific inhibitory control in children. SUBJECTS/METHODS: Children's (n = 48; Age 10.7 ±â€¯0.6 years) general characteristics, fat mass, cardiorespiratory fitness, blood pressure and performance on a food-specific inhibitory control task (Go/No-go) were measured across two sessions. RESULTS: Fat mass and sex were associated with inhibitory control performance, while no associations were found for cardiorespiratory fitness, blood pressure and other potential confounding variables (i.e. age, pubertal timing, body mass index, waist-to-hip ratio, scholar test performance and heart rate). Linear regression analyses showed that only fat mass predicted poorer food-specific inhibitory control (ß = 0.36; ΔR2 = 0.04; p < .05) and sex predicted inhibitory control for toys (control condition) (ß = 0.42; ΔR2 = 0.11; p < .01). Neither blood pressure nor cardiorespiratory fitness predicted food specific inhibitory control. CONCLUSION: These findings suggest that fat mass is an independent predictor of inhibitory control for food in children.

Improving cerebral oxygenation, cognition and autonomic nervous system control of a chronic alcohol abuser through a three-month running program.

The abusive use of alcohol has shown to be associated to cerebral damage, impaired cognition, poor autonomic nervous control, impaired cardiovascular health, increased levels of stress and anxiety, depression symptoms and poor quality of life. Aerobic exercise has shown to be an efficient tool to reduce and overcome these issues. In this case report, a patient (forty-four years old, male) under treatment in public psychiatric hospital, classified as having a substance use disorder, underwent a three-month running program. The maximal oxygen consumption increased from 24.2 ml/kg/min to 30.1 ml/kg/min, running time increased from 6 min to 45 min (650%) and distance covered from 765 m to 8700 m (1037.2%). In prefrontal cortex oxygenation, oxyhemoglobin levels improved by 76.1%, deoxyhemoglobin decreased 96.9% and total hemoglobin increased 78.8% during exercise. Reaction time in the cognitive test during rest decreased 23%, and the number of correct answers increased by 266.6%. Parasympathetic cardiac parameters increased in several heart rate variability indices. Thus, we conclude that running exercise performed by an alcoholic patient hospitalized in a psychiatric hospital improves cerebral function, cognition and cardiovascular health.