Monitoring lower limb biomechanical asymmetry and psychological measures in athletic populations-A scoping review.

BACKGROUND: Lower limb biomechanics, including asymmetry, are frequently monitored to determine sport performance level and injury risk. However, contributing factors extend beyond biomechanical and asymmetry measures to include psychological, sociological, and environmental factors. Unfortunately, inadequate research has been conducted using holistic biopsychosocial models to characterize sport performance and injury risk. Therefore, this scoping review summarized the research landscape of studies concurrently assessing measures of lower limb biomechanics, asymmetry, and introspective psychological state (e.g., pain, fatigue, perceived exertion, stress, etc.) in healthy, competitive athletes. METHODS: A systematic search of MEDLINE, Embase, CINAHL, SPORTDiscus, and Web of Science Core Collections was designed and conducted in accordance with PRISMA guidelines. Fifty-one articles were included in this review. RESULTS: Significant relationships between biomechanics (k = 22 studies) or asymmetry (k = 20 studies) and introspective state were found. Increased self-reported pain was associated with decreased range of motion, strength, and increased lower limb asymmetry. Higher ratings of perceived exertion were related to increased lower limb asymmetry, self-reported muscle soreness, and worse jump performance. Few studies (k = 4) monitored athletes longitudinally throughout one or more competitive season(s). CONCLUSION: This review highlights the need for concurrent analysis of introspective, psychological state, and biomechanical asymmetry measures along with longitudinal research to understand the contributing factors to sport performance and injury risk from biopsychosocial modeling. In doing so, this framework of biopsychosocial preventive and prognostic patient-centered practices may provide an actionable means of optimizing health, well-being, and sport performance in competitive athletes.

Physical and Cognitive Effects of High-Intensity Interval or Circuit-Based Strength Training for Community-Dwelling Older Adults: A Systematic Review.

Many older adults do not achieve recommended amounts of aerobic or strengthening exercise and high-intensity interval or circuit-based strengthening may offer a time-efficient solution. This review sought to determine the effects of high-intensity interval/circuit strengthening on physical and cognitive functioning for community-dwelling older adults, and its associated adherence, retention, and adverse events. Six databases were searched to June 2022 and 15 studies (11 for effectiveness) were included. The current certainty of evidence is low to very low; upper body-focused physical functioning measures demonstrated small to large benefits and lower body-focused, self-report, and cardiovascular measures had mixed results. There was insufficient evidence (one study) to determine cognitive effects. The mean adherence rates ranged from 73.5% to 95.8%, overall retention across all studies (n = 812) was 86%, and no serious adverse events were reported, suggesting that this type of exercise is feasible for community-dwelling older adults.

Dynamic task-linked switching between brain networks - A tri-network perspective.

The highly influential tri-network model proposed by Menon integrates 3 key intrinsic brain networks - the central executive network (CEN), the salience network (SN), and the default mode network (DMN), into a single cohesive model underlying normal behaviour and cognition. A large body of evidence suggests that abnormal intra- and inter- network connectivity between these three networks underlies the various behavioural and cognitive dysfunctions observed in patients with neuropsychiatric conditions such as PTSD and depression. An important prediction of the tri-network model is that the DMN and CEN networks are anti-correlated under the control of the SN, such that if a task engages one of the two, the SN inhibits the activation of the other. To date most of the evidence surrounding the functions of these three core networks comes from either resting state analyses or in the context of a single task with respect to rest. Few studies have investigated multiple tasks simultaneously or characterized the dynamics of task switching. Hence, a careful investigation of the temporal dynamics of network activity during task switching is warranted. To accomplish this we collected fMRI data from 14 participants that dynamically switched between a 2-back working memory task and an autobiographical memory retrieval task, designed to activate the CEN, DMN and the SN. The fMRI data were used to 1. identify nodes and sub-networks within the three major networks involved in task-linked dynamic network switching, 2. characterize the temporal pattern of activation of these nodes and sub-networks, and finally 3. investigate the causal influence that these nodes and sub-networks exerted on each other. Using a combination of multivariate neuroimaging analyses, timecourse analyses and multivariate Granger causality measures to study the tri-network dynamics, the current study found that the SN co-activates with the task-relevant network, providing a mechanistic insight into SN-mediated network selection in the context of explicit tasks. Our findings also indicate active involvement of the posterior insula and some medial temporal nodes in task-linked functions of the SN and DMN, warranting their inclusion as network nodes in future studies of the tri-network model. These results add to the growing body of evidence showing the complex interplay of CEN, DMN and SN nodes and sub-networks required for adequate task-switching, characterizing a normative pattern of task-linked network dynamics within the context of Menon's tri-network model.

Exercise training impacts skeletal muscle gene expression related to the kynurenine pathway.

Exercise positively impacts mood and symptoms of depression; however, the mechanisms underlying these effects are not fully understood. Recent evidence highlights a potential role for skeletal muscle-derived transcription factors to influence tryptophan metabolism, along the kynurenine pathway, which has important implications in depression. This has important consequences for older adults, whose age-related muscle deterioration may influence this pathway and may increase their risk for depression. Although exercise training has been shown to improve skeletal muscle mass in older adults, whether this also translates into improvements in transcription factors and metabolites related to the kynurenine pathway has yet to be examined. The aim of the present study was to examine the influence of a 12-wk exercise program on skeletal muscle gene expression of transcription factors, kynurenine aminotransferase (KAT) gene expression, and plasma concentrations of tryptophan metabolites (kynurenines) in healthy older men over 65 yr of age. Exercise training significantly increased skeletal muscle gene expression of transcription factors (peroxisome proliferator-activated receptor-γ coactivator 1α, peroxisome proliferator-activated receptor-α, and peroxisome proliferator-activated receptor-δ: 1.77, 1.99, 2.18-fold increases, respectively, P < 0.01] and KAT isoforms 1-4 (6.5, 2.1, 2.2, and 2.6-fold increases, respectively, P ≤ 0.01). Concentrations of plasma kynurenines were not altered. These results demonstrate that 12 wk of exercise training significantly altered skeletal muscle gene expression of transcription factors and gene expression related to the kynurenine pathway, but not circulating kynurenine metabolites in older men. These findings warrant future research to determine whether distinct exercise modalities or varying intensities could induce a shift in the kynurenine pathway in depressed older adults.

The Effects of Physical Exercise and Cognitive Training on Memory and Neurotrophic Factors.

This study examined the combined effect of physical exercise and cognitive training on memory and neurotrophic factors in healthy, young adults. Ninety-five participants completed 6 weeks of exercise training, combined exercise and cognitive training, or no training (control). Both the exercise and combined training groups improved performance on a high-interference memory task, whereas the control group did not. In contrast, neither training group improved on general recognition performance, suggesting that exercise training selectively increases high-interference memory that may be linked to hippocampal function. Individuals who experienced greater fitness improvements from the exercise training (i.e., high responders to exercise) also had greater increases in the serum neurotrophic factors brain-derived neurotrophic factor and insulin-like growth factor-1. These high responders to exercise also had better high-interference memory performance as a result of the combined exercise and cognitive training compared with exercise alone, suggesting that potential synergistic effects might depend on the availability of neurotrophic factors. These findings are especially important, as memory benefits accrued from a relatively short intervention in high-functioning young adults.

Formulation of evidence-based messages to promote the use of physical activity to prevent and manage Alzheimer's disease.

BACKGROUND: The impending public health impact of Alzheimer's disease is tremendous. Physical activity is a promising intervention for preventing and managing Alzheimer's disease. However, there is a lack of evidence-based public health messaging to support this position. This paper describes the application of the Appraisal of Guidelines Research and Evaluation II (AGREE-II) principles to formulate an evidence-based message to promote physical activity for the purposes of preventing and managing Alzheimer's disease. METHODS: A messaging statement was developed using the AGREE-II instrument as guidance. Methods included (a) conducting a systematic review of reviews summarizing research on physical activity to prevent and manage Alzheimer's disease, and (b) engaging stakeholders to deliberate the evidence and formulate the messaging statement. RESULTS: The evidence base consisted of seven systematic reviews focused on Alzheimer's disease prevention and 20 reviews focused on symptom management. Virtually all of the reviews of symptom management conflated patients with Alzheimer's disease and patients with other dementias, and this limitation was reflected in the second part of the messaging statement. After deliberating the evidence base, an expert panel achieved consensus on the following statement: "Regular participation in physical activity is associated with a reduced risk of developing Alzheimer's disease. Among older adults with Alzheimer's disease and other dementias, regular physical activity can improve performance of activities of daily living and mobility, and may improve general cognition and balance." The statement was rated favourably by a sample of older adults and physicians who treat Alzheimer's disease patients in terms of its appropriateness, utility, and clarity. CONCLUSION: Public health and other organizations that promote physical activity, health and well-being to older adults are encouraged to use the evidence-based statement in their programs and resources. Researchers, clinicians, people with Alzheimer's disease and caregivers are encouraged to adopt the messaging statement and the recommendations in the companion informational resource.

Age-related shift in neural complexity related to task performance and physical activity.

The human brain undergoes marked structural changes with age including cortical thinning and reduced connectivity because of the degradation of myelin. Although these changes can compromise cognitive function, the brain is able to functionally reorganize to compensate for some of this structural loss. However, there are interesting individual differences in outcome: When comparing individuals of similar age, those who engage in regular physical activity are less affected by the typical age-related decline in cognitive function. This study used multiscale entropy to reveal a shift in the way the brain processes information in older adults that is related to physical activity. Specifically, older adults who were more physically active engaged in more local neural information processing. Interestingly, this shift toward local information processing was also associated with improved executive function performance in older adults, suggesting that physical activity may help to improve aspects of cognitive function in older adults by biasing the neural system toward local information processing. In the face of age-related structural decline, the neural plasticity that is enhanced through physical activity may help older adults maintain cognitive health longer into their lifespan.

A trade-off between local and distributed information processing associated with remote episodic versus semantic memory.

Episodic memory and semantic memory produce very different subjective experiences yet rely on overlapping networks of brain regions for processing. Traditional approaches for characterizing functional brain networks emphasize static states of function and thus are blind to the dynamic information processing within and across brain regions. This study used information theoretic measures of entropy to quantify changes in the complexity of the brain's response as measured by magnetoencephalography while participants listened to audio recordings describing past personal episodic and general semantic events. Personal episodic recordings evoked richer subjective mnemonic experiences and more complex brain responses than general semantic recordings. Critically, we observed a trade-off between the relative contribution of local versus distributed entropy, such that personal episodic recordings produced relatively more local entropy whereas general semantic recordings produced relatively more distributed entropy. Changes in the relative contributions of local and distributed entropy to the total complexity of the system provides a potential mechanism that allows the same network of brain regions to represent cognitive information as either specific episodes or more general semantic knowledge.

Orienteering combines vigorous-intensity exercise with navigation to improve human cognition and increase brain-derived neurotrophic factor.

Exercise enhances aspects of human cognition, but its intensity may matter. Recent animal research suggests that vigorous exercise, which releases greater amounts of lactate, activates more brain-derived neurotrophic factor (BDNF) in the hippocampus and, thus, may be optimal for supporting cognitive function. The cognitive benefits of exercise may be further augmented when combined with cognitive training. The sport of orienteering simultaneously combines exercise with spatial navigation and, therefore, may result in greater cognitive benefits than exercising only, especially at vigorous intensities. The present study aimed to examine the effects of an acute bout of orienteering at different intensities on cognition and BDNF compared to exercising only. We hypothesized that vigorous-intensity orienteering would increase lactate and BDNF and improve cognition more than moderate-intensity orienteering or vigorous exercise alone. Sixty-three recreationally active, healthy young adults (Mage = 21.10±2.75 years) with no orienteering experience completed a 1.3 km intervention course by navigating and exercising at a vigorous (80-85% of heart rate reserve) or moderate (40-50% of heart rate reserve) intensity or exercising vigorously without navigation. Exercise intensity was monitored using peak lactate, heart rate and rating of perceived exertion. Serum BDNF was extracted immediately before and after the intervention. Memory was assessed using the Mnemonic Similarity Task (high-interference memory) and the Groton Maze Learning Test (spatial memory). Both exercising and orienteering at a vigorous intensity elicited greater peak lactate and increases in BDNF than moderate-intensity orienteering, and individuals with higher peak lactate also had greater increases in BDNF. High-interference memory improved after both vigorous-intensity interventions but did not improve after the moderate-intensity intervention. Spatial memory only increased after vigorous-intensity orienteering, suggesting that orienteering at a vigorous intensity may particularly benefit spatial cognition. Overall, the results demonstrate the benefits of vigorous exercise on human cognition and BDNF.

Longitudinal Monitoring of Biomechanical and Psychological State in Collegiate Female Basketball Athletes Using Principal Component Analysis.

Background: The growth in participation in collegiate athletics has been accompanied by increased sport-related injuries. The complex and multifactorial nature of sports injuries highlights the importance of monitoring athletes prospectively using a novel and integrated biopsychosocial approach, as opposed to contemporary practices that silo these facets of health. Methods: Data collected over two competitive basketball seasons were used in a principal component analysis (PCA) model with the following objectives: (i) investigate whether biomechanical PCs (i.e., on-court and countermovement jump (CMJ) metrics) were correlated with psychological state across a season and (ii) explore whether subject-specific significant fluctuations could be detected using minimum detectable change statistics. Weekly CMJ (force plates) and on-court data (inertial measurement units), as well as psychological state (questionnaire) data, were collected on the female collegiate basketball team for two seasons. Results: While some relationships (n = 2) were identified between biomechanical PCs and psychological state metrics, the magnitude of these associations was weak (r = |0.18-0.19|, p < 0.05), and no other overarching associations were identified at the group level. However, post-hoc case study analysis showed subject-specific relationships that highlight the potential utility of red-flagging meaningful fluctuations from normative biomechanical and psychological patterns. Conclusion: Overall, this work demonstrates the potential of advanced analytical modeling to characterize components of and detect statistically and clinically relevant fluctuations in student-athlete performance, health, and well-being and the need for more tailored and athlete-centered monitoring practices.

Females scan more than males: a potential mechanism for sex differences in recognition memory.

Recognition-memory tests reveal individual differences in episodic memory; however, by themselves, these tests provide little information regarding the stage (or stages) in memory processing at which differences are manifested. We used eye-tracking technology, together with a recognition paradigm, to achieve a more detailed analysis of visual processing during encoding and retrieval. Although this approach may be useful for assessing differences in memory across many different populations, we focused on sex differences in face memory. Females outperformed males on recognition-memory tests, and this advantage was directly related to females' scanning behavior at encoding. Moreover, additional exposures to the faces reduced sex differences in face recognition, which suggests that males may be able to improve their recognition memory by extracting more information at encoding through increased scanning. A strategy of increased scanning at encoding may prove to be a simple way to enhance memory performance in other populations with memory impairment.

Orienteering experts report more proficient spatial processing and memory across adulthood.

The closest surrogate to hunter-gather activity is the sport of orienteering, which naturally and simultaneously combines high-intensity interval exercise with navigation. Although human cognition can be improved across the lifespan through exercise and cognitive training, interventions like orienteering may be especially effective because they resemble activities engaged in by prehistoric humans during evolution. The present study tested whether orienteering experts have better hippocampal-dependent cognitive function than active, non-orienteering controls. One-hundred and fifty-eight healthy adults between the ages of 18 and 87 years old with varying experience in orienteering (none, intermediate, advanced, elite) reported on their spatial processing, spatial memory and episodic memory using the Navigational Strategy Questionnaire and the Survey of Autobiographical Memory. Orienteering experts reported greater use of allocentric and egocentric spatial processing and better spatial memory than controls. In contrast, episodic memory was not associated with orienteering expertise. Notably, the significant effects of orienteering on spatial cognition remained even after controlling for age, sex, and physical activity, suggesting that orienteering may be an effective intervention to prevent age-related cognitive decline in spatial navigation and memory.

Mental Health in Adults With ADHD: Examining the Relationship With Cardiorespiratory Fitness.

OBJECTIVE: The mental health of adults with ADHD was compared to neurotypical controls, and associations between cardiorespiratory fitness (CRF) and mental health were examined. METHOD: Seventy-two participants (n = 36 with ADHD) completed demographic questions assessing ADHD and mental health symptoms. CRF was estimated using the 6-Minute Walk Test and a self-perception question. RESULTS: Those with ADHD had significantly poorer mental health outcomes than controls (p < .001), with 50% of adults with ADHD reporting severe to extremely severe symptoms of depression, anxiety, and stress. Critically, lower CRF was associated with worse depression, anxiety, and stress (all p ≤ .03) across both groups. Within the ADHD group, those with higher estimated CRF had significantly lower stress. Among participants with less severe ADHD symptoms, those with higher perceived CRF had significantly lower depressive symptoms. CONCLUSION: In our cross-sectional study, participants with ADHD had poorer mental health than neurotypical controls, and higher fitness was associated with better mental health.

Correction: Ogrodnik et al. Exploring the Relationship between Cardiorespiratory Fitness and Executive Functioning in Adults with ADHD. Brain Sci. 2023, 13, 673.

During the final proofreading step of this paper [...].

Exploring the Relationship between Cardiorespiratory Fitness and Executive Functioning in Adults with ADHD.

OBJECTIVE: Associations between measures of executive functioning (EF) and cardiorespiratory fitness (CRF) were examined for adults with and without ADHD. METHOD: Measures of executive functioning including the Stroop task, Wisconsin Card Sorting task, and Operation Span Task were completed virtually (n = 36 ADHD; n = 36 Control). Participants completed the Six-Minute Walk Test to estimate CRF. RESULTS: Mean performance measures of executive function did not differ by group. However, higher estimated CRF was associated with better Stroop task performance, and the association was strongest for individuals with ADHD. CONCLUSION: In adults with ADHD, higher estimated CRF was associated with better inhibitory control, but not with other measures of executive functioning.

Exploring Barriers and Facilitators to Physical Activity in Adults with ADHD: A Qualitative Investigation.

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by executive dysfunction. Physical activity (PA) may improve executive dysfunction; however, specific barriers and facilitators to PA participation for adults with ADHD have not been formally documented, which was the aim of the present study. Thirty adults with ADHD completed virtual semi-structured interviews, which were analyzed thematically and guided by the Theoretical Domains Framework. Expressions of both barriers and facilitators to PA were identified. Themes such as executive dysfunction (described as forgetfulness, difficulty with sustained focus, and time management), poor self-esteem, and lack of motivation were seen as barriers to PA. Key facilitators were tied to the benefits of being physically active including improvements in executive functioning, mood, and mental health during and after activity, as well as the enjoyment of being active with others. To better support adults with ADHD in initiating physical activity, it is crucial to develop unique resources that are tailored to their specific needs. These resources should be designed to minimize barriers and maximize facilitators, while also supporting the awareness and acceptance of neurodiverse experiences.

Relating brain signal variability to knowledge representation.

We assessed the hypothesis that brain signal variability is a reflection of functional network reconfiguration during memory processing. In the present experiments, we use multiscale entropy to capture the variability of human electroencephalogram (EEG) while manipulating the knowledge representation associated with faces stored in memory. Across two experiments, we observed increased variability as a function of greater knowledge representation. In Experiment 1, individuals with greater familiarity for a group of famous faces displayed more brain signal variability. In Experiment 2, brain signal variability increased with learning after multiple experimental exposures to previously unfamiliar faces. The results demonstrate that variability increases with face familiarity; cognitive processes during the perception of familiar stimuli may engage a broader network of regions, which manifests as higher complexity/variability in spatial and temporal domains. In addition, effects of repetition suppression on brain signal variability were observed, and the pattern of results is consistent with a selectivity model of neural adaptation.

Cardiorespiratory Fitness May Protect Memory for Poorer Sleepers.

OBJECTIVES: Physical activity has been shown to protect executive functions against the deleterious effects of poorer sleep among older adults (OA); however, it is unknown whether memory is protected too, and if this relationship differs by age. The present study investigated the relationship between cardiorespiratory fitness, sleep, and memory in both older and young adults (YA). METHODS: This observational study recruited 26 OA (70.7 ± 2.8 years) and 35 YA (21.0 ± 3.1 years). Participants completed the Rockport 1-mile walk test to evaluate cardiorespiratory fitness. Participants wore an actigraph for 1 week to measure habitual sleep and returned for a second visit to perform the memory tests. The interaction between cardiorespiratory fitness and sleep to predict memory was assessed separately in OA and YA. RESULTS: In OA, cardiorespiratory fitness significantly moderated the relationship between memory and sleep quality, specifically number of nighttime awakenings, sleep efficiency, and wake after sleep onset. Further analyses reveal that a high number of nighttime awakenings and low sleep efficiency significantly predicted worse memory performance in the low fit OA, but high fit OA. Notably, every nighttime awakening was associated with a nearly 4% decrease in memory in low fit OA, but not high fit OA. Wake after sleep onset did not significantly predict memory in either fitness group. No interaction was found when looking at sleep duration or self-report sleep quality in OA and no significant interactions were observed between fitness, sleep, and memory in YA. CONCLUSION: Overall, the results suggest that cardiorespiratory fitness may act as a protective buffer for memory in OA with poor sleep quality. These same was not true for YA suggesting that the protective effects of cardiorespiratory fitness on sleep-related memory impairments may be age specific.

Physical Activity and Mindfulness are Associated with Lower Anxiety in Different but Complementary Ways.

Introduction: Anxiety is the most prevalent mental illness worldwide. Physical activity and mindfulness both reduce anxiety. The two are highly related; however, the relative association of physical activity and mindfulness on anxiety has yet to be examined. The present study aimed to evaluate the unique variance accounted for by physical activity and mindfulness on anxiety. Methods: Fifty young adults from a student population (M ± SD = 19 ± 0.2 years old; 58% female) reported their physical activity, mindfulness, and anxiety symptoms at the start of the study and reported their change in state anxiety to an acute psychological stress test, Trier Social Stress Test. Results: Mindfulness explained more of the variance associated with anxiety symptoms at baseline, whereas physical activity explained more of the variance associated with change in state anxiety in response to the acute stressor. Females had higher rates of anxiety symptoms than males suggesting that females may benefit more from mindfulness. In contrast, both males and females reacted similarly to an acute stressor suggesting that both genders may benefit from physical activity. Conclusions: Our findings suggest that physical activity and trait mindfulness may have related, but distinct impacts on anxiety levels. These results have important implications for using these lifestyle interventions to support mental health and point to personalizing interventions to help ease the burden of anxiety felt by the individual.

Measurement Properties of Remotely or Self-Administered Lower Extremity Mobility Performance Measures in Adults: A Systematic Review.

OBJECTIVE: For individuals who face barriers to care assessment, there is a need for remote administration or self-administration of physical performance measures that assess mobility to determine current functional status and to monitor and predict future changes in functional status. The primary purpose of this review is to evaluate the available measurement properties of scores for remotely or self-administered lower extremity mobility performance measures in adults. This review also outlines the test procedures and population suitability of these measures. METHODS: Data sources were Ovid MEDLINE, Ovid Embase, EBSCOhost CINAHL, Ovid AMED, and Cochrane CENTRAL-which were searched from inception to January 26, 2021-and the reference lists of relevant studies. Two individuals independently screened studies that assessed at least 1 prespecified measurement property of scores for a remote and/or self-administered lower extremity physical performance measure assessing mobility in an adult population. Two individuals independently extracted data on study characteristics, measurement properties, feasibility, and interpretability using piloted extraction forms. The COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) Risk of Bias tool was used to assess methodological quality. Data were qualitatively summarized, and results were compared against COSMIN's criteria for good measurement properties. Level of evidence was determined using COSMIN's modified GRADE approach. RESULTS: Fourteen studies detailing 19 outcome measures were included. Many studies displayed "sufficient" measurement properties based on COSMIN's criteria; however, risk of bias for most of the included studies was rated adequate or doubtful. CONCLUSION: Clinicians and researchers can consider the measurement properties of scores and feasibility of different approaches presented in this review when determining how to assess or monitor mobility in adult populations. IMPACT: Assessing mobility via remote or self-administered physical performance measures in adult populations appears to be feasible using a variety of methods including simple tools (chair, stopwatch), videoconferencing, and smartphone applications. This strategy may be particularly valuable for self-management of chronic conditions and decreasing barriers to accessing care.