Association between habitual physical activity on episodic memory strategy use and memory controllability

© 2019 The Author(s). Background:The primary objective of this study was to evaluate the association between habitual physical activity engagement and perceived controllability of memory function. Secondary objectives included the evaluation of physical activity on memory strategy use, and whether the latter mediates the relationship between physical activity on memory controllability. Methods: Two-hundred and nine young adults (M age =25 y) completed a brief survey evaluating physical activity (Physical Activity Vital Signs Questionnaire), memory strategy use (Memory Functioning Questionnaire), and memory controllability (Memory Controllability Inventory). Results: Physical activity was not associated with memory strategy use (β=0.68; 95% CI: -1.25, 2.62; P=0.48), nor was memory strategy use associated with memory controllability. Physical activity was consistently associated with various attributes of memory controllability, including Present Ability (β=1.10; 95% CI: 0.07, 2.12; P=0.03), Potential Improvement (β=0.84; 95% CI: 0.05, 1.63; P=0.03), Effort Utility (β=0.87; 95% CI: 0.11, 1.61; P=0.02), Inevitable Decrement (β=-1.19; 95% CI: -2.19, -0.19; P=0.02) and Alzheimer’s likelihood (β=-1.21; 95% CI: -2.29, -0.12; P=0.02). Conclusion: Physical activity is consistently associated with greater perceptions of memory controllability. Future longitudinal and experimental work on this topic is warranted to evaluate if physical activity can foster an individual’s ability to modify their behavior and cognitions to enhance and preserve memory function

Health behavior characteristics and all-cause mortality

AbstractObjectiveTo examine the potential dose–response relationship between four positive health characteristics (i.e., normal body mass index, physically active, healthy diet and non-smoker) and all-cause mortality.MethodsData from the 2003–2006 NHANES were used (20+years; N=5844), with follow-up through 2011. Participants wore an ActiGraph 7164 accelerometer over a period of up to 7days to assess physical activity. Dietary behavior and smoking were assessed via self-report. Body mass index was measured using standard procedures.ResultsThere was a clear dose–response relationship between the number of positive health characteristics and all-cause mortality. After adjusting for age, gender, race-ethnicity and comorbid illness, and compared to those with 0 positive health characteristics, those with 1, 2, 3, and 4, respectively, had a 39% (HR=0.61; 95% CI: 0.40–0.94), 48% (HR=0.52; 95% CI: 0.34–0.80), 62% (HR=0.38; 95% CI: 0.22–0.64) and 88% (HR=0.12; 95% CI: 0.05–0.29) reduced risk of all-cause mortality.ConclusionsAdoption of more positive health characteristics is associated with greater survival

Physical activity and cognitive function among older adults with an elevated gamma gap

© 2018 The Author(s) Published by S. Karger AG, Basel. Objective: An elevated gamma gap is indicative of high serum concentrations of globulin proteins, some of which elicit acute inflammatory responses. An impaired cognitive function has been linked to central and peripheral inflammation, while exercise is associated with protective, anti-inflammatory benefits. In this study, we evaluated whether the gamma gap is associated with cognitive function among older adults and whether physical activity is favorably associated with cognitive function among those with an elevated gamma gap. Materials and Methods: Data from the 1999-2002 National Health and Nutrition Examination Survey (NHANES) were used to identify 2,352 older adults aged between 60 and 85 years. The gamma gap was evaluated by subtracting albumin from total protein, i.e., gamma gap = total protein (g/dL)- A lbumin (g/dL). Those at or above 3.1 g/dL (31.0 g/L) were considered to have an elevated gamma gap. The Digit Symbol Substitution Test (DSST) was used to assess cognitive function tasks of pairing and free recall among participants. Participants were asked open-ended questions about participation in leisure-time physical activity over the previous 30 days. Results: Those with an elevated gamma gap (DSST, 44.8) had a lower cognitive function score when compared to those without an elevated gamma gap (DSST, 50.1) (p \u3c 0.001). After adjustments, and among those with an elevated gamma gap, those meeting the moderate-to-vigorous intensity physical activity (MVPA) guidelines (vs. not meeting them) had a DSST score of 6.42 units higher (β = 6.42, 95% CI 3.85-8.99, p \u3c 0.001). Conclusion: In this national sample of older adults, the gamma gap was associated with cognitive function, and among those with an elevated gamma gap, meeting the physical activity guidelines was associated with a higher cognitive function. Relevant clinical implications are discussed, as the gamma gap may be predictive of the risk for early mortality and reduced quality of life. Experimental work is needed to investigate whether physical activity training programs are effective in reducing an elevated gamma gap and preserving optimal cognitive functioning among at-risk individuals

Acute exercise and mindfulness meditation on learning and memory: Randomized controlled intervention

© 2019 The Author(s). Background: The purpose of this experiment was to evaluate the potential combined effects of acute exercise and mindfulness mediation on episodic memory. Methods: All data collection occurred in the authors’ laboratory (January to May of 2019). In this three-arm, within-subject design, participants (N=20; Mage=21.6 years) completed three counterbalanced laboratory visits, including Exercise Only, Exercise + Meditation and Control. Learning and memory were assessed from a word-list task. A one-factor repeated-measures ANOVA was computed for two memory outcomes, including the learning outcome (average performance across the 6 trials) and the long-term memory recall (10-minute delay). Results: The exercise conditions had a greater learning effect when compared to the Control visit, Mdiff = 0.68 (95% CI: 0.10, 1.25), P = 0.02. The Exercise + Memory visit had better long-term memory when compared to Exercise Only, Mdiff = 0.95 (95% CI: 0.07, 1.83), P = 0.03. Conclusion: The present experiment provides suggestive evidence that acute exercise may enhance learning and, when coupling acute exercise prior to encoding with meditation during early consolidation, long-term memory may be enhanced

Association Between Perceived Physical Activity and Cognitive Function in Older Adults

© The Author(s) 2018. There is irrefutable evidence that regular participation in physical activity is favorably associated with numerous positive health outcomes, including cognitive function. Emerging work suggests that perceived physical activity, independent of actual physical activity behavior, is inversely associated with mortality risk. In this study, we evaluate whether perceived physical activity, independent of actual physical activity, is associated with cognitive function, a robust indicator of mortality risk. Data from the cross-sectional 1999–2002 National Health and Nutrition Examination Survey were employed (N = 2352; 60+ years of age). Actual physical activity was assessed via a validated survey. Perceived physical activity was assessed using the following question: “Compared with others of the same age, would you say that you are: more active, less active, or about the same?” Cognitive function was assessed from the Digit Symbol Substitution Test. When examined in separate models, both actual and perceived physical activity were positively and statistically significantly associated with cognitive function. However, when considered in the same model, actual physical activity was no longer statistically significantly associated with cognitive function, but perceived physical activity was. Perceived physical activity, independent of actual physical activity, is independently associated with cognitive function. If these findings are replicated, future work should consider evaluating perceived physical activity when examining the effects of actual physical activity behavior on cognitive function

Physical activity, muscle-strengthening activities, and systemic inflammation among retinopathy patients

© 2018 by the American Diabetes Association. Objective. We evaluated the specific association between muscle-strengthening activity (MSA) and accelerometer-assessed physical activity on systemic inflammation among retinopathy patients in the United States. Methods. Data from the 2005–2006 National Health and Nutrition Examination Survey (NHANES) were used to identify 157 retinopathy patients between 40 and 85 years of age with complete data on select study variables. MSA was assessed via self-report. Participation in moderate-to-vigorous physical activity (MVPA) was determined from objective accelerometer data. Systemic inflammation was assessed using C-reactive protein (CRP), which was quantified using latex-enhanced nephelometry. Nonproliferative retinopathy was determined using Early Treatment Diabetic Retinopathy Study grading criteria, as well as objective retinal imaging assessments using the Canon Non-Mydriatic Retinal Camera CR6-45NM. Individuals were excluded if they had been diagnosed with coronary artery disease, congestive heart failure, heart attack, or stroke. Results. MVPA (β = –0.004, 95% CI – 0.007 to – 0.001, P = 0.006) but not MSA (β = –0.0001, 95% CI – 0.002 to 0.001, P = 0.86) was associated with lower CRP levels. Additionally, for a more substantive 30 minutes/day increase in MVPA, there was a corresponding 0.12 mg/dL decrease in CRP. Conclusion. In this nationally representative sample of adults, only individuals who engaged in higher levels of MVPA had lower CRP levels, which is indicative of reduced systemic inflammation. MSA was not associated with systemic inflammation among this cohort. Our findings suggest that MVPA is inversely associated with systemic inflammation among retinopathy patients, which is noteworthy because increased systemic inflammation may facilitate retinopathic severity

The effects of acute exercise on episodic memory function among young university students: Moderation considerations by biological sex

© 2019 The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License Background: The objective of this study was to evaluate potential sex-specific differences on episodic memory function and determine whether sex moderates the effects of acute exercise on episodic memory. Methods: A randomized controlled intervention was employed. This experiment was conducted among young University students (mean age = 21 years). Both males (n=20) and females (n=20) completed two counterbalanced laboratory visits, with one visit involving a 15-minute bout of moderate-intensity exercise prior to the memory task. The control visit engaged in a time-matched seated task. Memory function (including short-term memory, learning, and long-term memory) was assessed from the RAVLT (Rey Auditory Verbal Learning Test). Results: We observed a significant main effect for time (P\u3c 0.001, ƞ2p= 0.77) and a marginally significant main effect for sex (P= 0.06, ƞ2p= 0.09), but no time by sex by condition interaction (P= 0.91, ƞ2p= 0.01). We also observed some suggestive evidence of a more beneficial effect of acute exercise on memory for females. Conclusion: In conclusion, females outperformed males in verbal memory function. Additional research is needed to further evaluate whether sex moderates the effects of acute exercise on memory function

The Association of Self-reported Physical Activity on Human Sensory Long-term Potentiation

Exercise has been shown to enhance synaptic plasticity, therefore, potentially affecting memory. While the mechanism(s) responsible for this relationship have been explored in animal models, current research suggests that exercise may possess the ability to induce synaptic long-term potentiation (LTP). Most of the LTP mechanistic work has been conducted in animal models using invasive procedures. For that reason, the purpose of the present experiment was to investigate whether self-reported exercise is related to human sensory LTP-like responses. Nineteen participants (MAGE= 24 years; 52.6% male) completed the study. Long-term potentiation-like responses were measured by incorporating a non-invasive method that assess the change in potentiation of the N1b component produced from the visual stimulus paradigm presented bilaterally in the visual field. Results demonstrated that those with higher levels of moderate-to-vigorous physical activity (MVPA) had a greater N1b change from baseline to the early time period assessment, r = −0.43, p = 0.06. Our findings provide some suggestive evidence of an association between self-reported MVPA and LTPlike responses. Additional work is needed to support that the potentiation of the human sensory N1b component in the observed study is due to the exercise-induced synaptic changes similar to that detailed in prior animal research

Pilot Experimentation of the Accuracy of Accelerometer Activity Count-Derived Breaks in Sedentary Time

Introduction: The purpose of this study was toconduct a pilot experimentation of the accuracy of the ActiGraph GT9X model in detecting breaks from sedentary behavior. Methods: Participants completed six transitional-based sedentary break activities while wearing an ActiGraph GT9X accelerometer. Data were processed using both the default filter and low-frequency extension filter. Direct observation was used as the criterion to observe a break in sedentary behavior. Trial 1 included the transition from sitting to standing; trial 2, sitting to walking for 30 sec; trial 3, sitting to walking for 1 min; trial 4, standing to walking for 30 sec; trial 5, standing to walking for 1 min; and trial 6, standing to sitting. Results: For both the default and low-frequency filter, the accelerometer only detected a break 10% of the time for trial 1. Accuracy was also low (<40%) for trial 6. However, accuracy was perfect (100%) for trials 2-5. Conclusion: The ActiGraph GT9X accelerometer was inaccurate in detecting a sedentary break when transitioning from a sitting to standing position but was accurate for other transitional shifts

High-intensity acute exercise and directed forgetting on memory function

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Background and Objectives: Despite accumulating research demonstrating that acute exercise may enhance memory function, very little research has evaluated whether acute exercise can effectuate intentional directed forgetting (DF), an adaptative strategy to facilitate subsequent memory performance. Materials and Methods: A three-arm parallel-group randomized controlled intervention was employed. Participants were randomized into one of three groups, including: (1) exercise plus DF (Ex + DF), (2) DF (directed forgetting) only (DF) and (3) R (remember) only (R). The acute bout of exercise included 15 min of high-intensity treadmill exercise. The memory assessment involved the presentation of two-word lists. After encoding the first word list, participants were either instructed to forget all of those words (DF) or to remember them. Following this, participants encoded the second word list. Results: We observed a statistically significant main effect for list F(1, 57) = 12.27, p \u3c 0.001, η2 p = 0.18, but no main effect for group F(2, 57) = 1.32, p = 0.27, η2 p = 0.04, or list by group interaction, F(2, 57) = 2.89, p = 0.06, η2 p = 0.09. Conclusion: This study demonstrates a directed forgetting effect in that cueing an individual to forget a previously encoded list of items facilitates memory performance on a subsequent list of items. However, we failed to demonstrate any beneficial effect of acute exercise in facilitating directed forgetting. These findings are discussed in the context of directed forgetting theories, particularly the attention inhibition mechanism, as well as the timing of the acute bout of exercise