Summary: Creating a negative energy balance by decreasing caloric consumption and increasing physical activity is a common strategy used to treat obesity. A large number of review and original research papers have considered the role of physical activity in weight loss and maintenance. However, their conclusions are at times conflicting. In this review, we have critically evaluated the findings of systematic reviews and meta‐analyses and supplemented their conclusions with recently published, high‐quality clinical trials. We have eliminated studies that were methodologically flawed in an attempt to reduce the ambiguity in the literature. We further sought, through selective review of these publications, to isolate the effects of various types of exercise, independent of dietary interventions, to further clarify their independent contributions. Thus, our review describes (i) combined calorie restriction with physical activity interventions, (ii) physical activity interventions without calorie restriction and (iii) the role of physical activity on maintenance of weight loss. Through this critical examination of the literature, we have provided conclusions to address certain ambiguities regarding the role of physical activity in obesity treatment that will inform clinical practice. We have also identified several long‐standing gaps in knowledge that will inform future research.

Autism spectrum disorders represent a group of neurodevelopmental differences commonly diagnosed in childhood, characterized by impaired communication and social interactions and restricted, repetitive behaviors.¹ Autism has a prevalence of 17 per 1000 children in the US,² and a global prevalence of 23 per 1000.³ Autism is associated with multiple medical, neurologic, and psychiatric comorbidities.^4-6 These comorbidities often exacerbate disparities in the quality of life and life expectancy of individuals with autism.⁷

Sleep is closely related to physical and mental health problems as well as problem behaviors among adolescents and young adults. Thus, to better understand sleep seems paramount, including how to best measure it. The Pittsburgh Sleep Quality Index (PSQI) is one of the most widely used sleep measures. Some recent psychometric evidence (i.e., inconsistent dimensionality across studies) has called into question the application of this clinically developed measure. The current study sought to rigorously test the dimensionality of the measure, by comparing a psychometric application of it to a clinical application. It also tested correlates of sleep quality measured by the PSQI, including academic achievement, mental health, and substance use (alcohol and drug use) . Data were collected from 820 college students using an online computer-assisted protocol. Results from factor analyses supported a 2-factor solution for the PSQI. Findings from path analyses using scale scores based on the extracted factor structure as the independent variable provided evidence that the psychometric approach worked equally well as the clinical application using the global sleep quality risk score , providing some support for the use of a psychometric approach of the PSQI. Sleep quality scores (both scale and global sleep quality risk scores) were consistently associated with academic achievement, mental health, and substance use problems, thus providing further support on the importance of good sleep for young adults. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Objective: l-theanine is a constituent of tea which is claimed to enhance cognitive functions. We aimed to determine whether theanine and theanine–caffeine combination have acute positive effects on cognitive and neurophysiological measures of attention, compared to caffeine (a positive control) and a placebo in healthy individuals. Design: In a placebo-controlled, five-way crossover trial in 20 healthy male volunteers, we compared the effects of l-theanine (200 mg), caffeine (160 mg), their combination, black tea (one cup) and a placebo (distilled water) on cognitive (simple [SVRT] and recognition visual reaction time [RVRT]) and neurophysiological (event-related potentials [ERPs]) measures of attention. We also recorded visual (VEPs) and motor evoked potentials (MEPs) to examine any effects of treatments on peripheral visual and motor conduction, respectively. Results: Mean RVRT was significantly improved by theanine (P = 0.019), caffeine (P = 0.043), and theanine–caffeine combination (P = 0.001), but not by tea (P = 0.429) or placebo (P = 0.822). VEP or MEP latencies or SVRT did not show significant inter-treatment differences. Theanine (P = 0.001) and caffeine (P = 0.001) elicited significantly larger mean peak-to-peak N2-P300 ERP amplitudes than the placebo, whereas theanine–caffeine combination elicited a significantly larger mean N2-P300 amplitude than placebo (P < 0.001), theanine (P = 0.029) or caffeine (P = 0.005). No significant theanine × caffeine interaction was observed for RVRT or N2-P300 amplitude. Discussion: A dose of theanine equivalent of eight cups of back tea improves cognitive and neurophysiological measures of selective attention, to a degree that is comparable with that of caffeine. Theanine and caffeine seem to have additive effects on attention in high doses.

We examined the acute effects of l-theanine, caffeine and their combination on sustained attention, inhibitory control and overall cognition in boys with attention deficit hyperactivity disorder (ADHD). l-Theanine (2.5 mg/kg), caffeine (2.0 mg/kg), their combination and a placebo were administered in a randomized four-way repeated-measures crossover with washout, to five boys (8–15 years) with ADHD. Functional magnetic resonance imaging (fMRI) was performed during a Go/NoGo task and a Stop-signal task ~ 1 h post-dose. NIH Cognition Toolbox was administered ~ 2 h post-dose. Treatment vs. placebo effects were examined in multi-level mixed-effects models. l-Theanine improved total cognition composite in NIH Cognition Toolbox (p = 0.040) vs. placebo. Caffeine worsened and l-theanine had a trend of worsening inhibitory control (i.e. increased Stop-signal reaction time; p = 0.031 and p = 0.053 respectively). l-Theanine–caffeine combination improved total cognition composite (p = 0.041), d-prime in the Go/NoGo task (p = 0.033) and showed a trend of improvement of inhibitory control (p = 0.080). l-Theanine–caffeine combination was associated with decreased task-related reactivity of a brain network associated with mind wandering (i.e. default mode network). l-Theanine–caffeine combination may be a potential therapeutic option for ADHD-associated impairments in sustained attention, inhibitory control and overall cognitive performance.