Tai Chi Expertise Classification in Older Adults Using Wrist Wearables and Machine Learning.

Tai Chi is a Chinese martial art that provides an adaptive and accessible exercise for older adults with varying functional capacity. While Tai Chi is widely recommended for its physical benefits, wider adoption in at-home practice presents challenges for practitioners, as limited feedback may hamper learning. This study examined the feasibility of using a wearable sensor, combined with machine learning (ML) approaches, to automatically and objectively classify Tai Chi expertise. We hypothesized that the combination of wrist acceleration profiles with ML approaches would be able to accurately classify practitioners' Tai Chi expertise levels. Twelve older active Tai Chi practitioners were recruited for this study. The self-reported lifetime practice hours were used to identify subjects in low, medium, or highly experienced groups. Using 15 acceleration-derived features from a wearable sensor during a self-guided Tai Chi movement and 8 ML architectures, we found multiclass classification performance to range from 0.73 to 0.97 in accuracy and F1-score. Based on feature importance analysis, the top three features were found to each result in a 16-19% performance drop in accuracy. These findings suggest that wrist-wearable-based ML models may accurately classify practice-related changes in movement patterns, which may be helpful in quantifying progress in at-home exercises.

Yoga Impacts Cognitive Health: Neurophysiological Changes and Stress Regulation Mechanisms.

Yoga, a physical and contemplative practice, offers the practitioner a unique mind-body exercise experience demonstrating preliminary efficacy in improving cognitive health. We examine the evidence for underlying mechanisms that explain the yoga-cognition relationship in healthy older adults. The cognitive benefits of yoga may be the result of improved stress regulation and neurocognitive resource efficiency that facilitate bidirectional brain-body communication.

Macular Xanthophylls and Markers of the Anterior Visual Pathway among Persons with Multiple Sclerosis.

BACKGROUND: Multiple sclerosis (MS) can cause retinal thinning among persons with MS with optic neuritis (MS-ON). Macular xanthophylls are carotenoids that comprise the macular pigment, filtering blue light and countering photo-oxidation. However, macular xanthophyll status and its implications for markers of neuroaxonal degeneration have not been examined in MS. OBJECTIVES: This study characterized differences in macular and serum xanthophylls, and retinal morphometry [retinal nerve fiber layer thickness at the macular (mRNFL) and optic disc (odRNFL) and total macular volume (TMV)] in individuals with MS and healthy controls (HC). Associations between macular pigment optical density (MPOD) and retinal morphometry were also examined. METHODS: Adults aged 45-64 y (HC, n = 42; MS, n = 40) participated in a cross-sectional study. MPOD was measured via heterochromatic flicker photometry. Retinal morphometry was measured via optical coherence tomography (OCT). Serum carotenoids were quantified using HPLC. Dietary carotenoids were collected using 7-d records. One-factor ANOVA was conducted to determine group effects on macular, serum, and dietary carotenoids. Partial correlations examined the relations between MPOD, retinal morphometry, diet, and serum carotenoids. RESULTS: Relative to HC, persons with MS-ON had lower MPOD (Cohen's d = 0.84, P = 0.014), lower odRNFL (Cohen's d = 2.16, P <0.001), lower mRNFL (Cohen's d = 0.57, P = 0.028), and lower TMV (Cohen's d = 0.95, P = 0.011). MS without ON (MS) had lower odRNFL (Cohen's d = 0.93, P = 0.001) than HC and lower serum lutein than MS-ON subjects (Cohen's d = 0.65, P = 0.014). Among MS, MPOD was positively correlated with odRNFL thickness (ρ = 0.43, P = 0.049) and TMV (ρ = 0.45, P = 0.039), whereas odRNFL was negatively correlated with serum lutein (ρ = -0.68, P = 0.016) and zeaxanthin (ρ = -0.62, P = 0.028). CONCLUSIONS: Persons with MS-ON exhibited poorer xanthophyll status in the macula and serum. MPOD was associated with beneficial anatomical features in the MS group. These findings warrant confirmation with larger cohorts and prospective trials to evaluate xanthophyll effects on the anterior visual pathway in MS.

Energy Expenditure Validation of an Exergame Platform: Ring Fit Adventure Use in Adults with Overweight and Obesity.

Objective: This study aims at comparing the energy expenditure (EE) and heart rate (HR) data from Ring Fit Adventure (RFA) with those from indirect calorimetry (COSMED) and a heart rate monitor (Polar FT7). A secondary goal is to evaluate self-reported enjoyment and perceived effort levels. Materials and Methods: Thirty participants (age = 21.8 ± 2.2; body mass index = 31.8 ± 4.4) were recruited for two laboratory visits. The first visit involved baseline measurements. In the second visit, participants performed a 55-minute ad libitum exercise session with the RFA in adventure mode with moderate difficulty. During this session, EE, HR, perceived effort, and enjoyment of physical activity were recorded. Results: Although no statistically significant overestimation of EE was found between the RFA and the metabolic cart, two-way analysis of variance results show a main effect of condition (RFA vs. Polar FT7) on HR (122.8 ± 20.1 bpm and 129.0 ± 18.6 bpm; P = 0.007; ᶯp2 = 0.235). Based on comprehensive statistical evaluations, including the mean absolute percent error, intraclass correlations, typical error of measurement, and limits of agreement, the data suggest that the RFA provides reliable estimates for EE and HR. Overall, participants enjoyed the game considerably (71.3 ± 5.9/80 arbitrary units), and their reported perceived exertion was low. Conclusion: This study underscores that the RFA values are relatively accurate and precise, and thus it can be safely suggested for individuals with overweight and obesity to adopt an active lifestyle.

Neuroprotective influence of macular xanthophylls and retinal integrity on cognitive function among persons with multiple sclerosis.

BACKGROUND: No studies to date have examined if macular xanthophyll accumulation and retinal integrity are independently associated with cognitive function in individuals with multiple sclerosis (MS). This study explored whether macular xanthophyll accumulation and structural morphometry in the retina were associated with behavioral performance and neuroelectric function during a computerized cognitive task among persons with MS and healthy controls (HCs). METHODS: 42 HCs and 42 individuals with MS aged 18-64 years were enrolled. Macular pigment optical density (MPOD) was measured using heterochromatic flicker photometry. Optic disc retinal nerve fiber layer (odRNFL), macular retinal nerve fiber layer, and total macular volume were assessed via optical coherence tomography. Attentional inhibition was assessed using an Eriksen flanker task while underlying neuroelectric function was recorded using event-related potentials. RESULTS: Persons with MS had a slower reaction time, lower accuracy, and delayed P3 peak latency time during both congruent and incongruent trials compared with HCs. Within the MS group, MPOD explained variance in incongruent P3 peak latency, and odRNFL explained variance in congruent reaction time and congruent P3 peak latency. CONCLUSIONS: Persons with MS exhibited poorer attentional inhibition and slower processing speed, yet higher MPOD and odRNFL levels were independently associated with greater attentional inhibition and faster processing speed among persons with MS. Future interventions are necessary to determine if improvements in these metrics may promote cognitive function among persons with MS.

Moderate-to-Vigorous Physical Activity is Related With Retinal Neuronal and Axonal Integrity in Persons With Multiple Sclerosis.

BACKGROUND: Moderate-to-vigorous physical activity (MVPA) may confer benefits for axonal and/or neuronal integrity in adults with multiple sclerosis (MS). PURPOSE: Examine the association between device-measured MVPA with optical coherence tomography (OCT) metrics of retinal nerve fiber layer (RNFL) thickness and total macular volume (TMV) in persons with and without MS. METHODS: Adults with MS (N = 41), along with sex-matched healthy control (HC) participants (N = 79), underwent measurements of retinal morphology via OCT and wore an accelerometer for a period of 7 days as a measure of MVPA. RESULTS: Persons with MS had significantly lower MVPA, RNFL thickness, and TMV compared with HCs. MVPA was correlated with RNFL (r = .38, P < .01) thickness and TMV (r = .49, P < .01). Hierarchical linear regression analyses indicated that addition of MVPA attenuated the Group effect on RNFL and TMV. MVPA accounted for 8% and 3% of the variance in TMV (ß = .343, P < .01) and RNFL thickness (ß = .217, P = .03), respectively. CONCLUSION: MVPA was positively associated with axonal and neuronal integrity assessed by OCT and partially explained group differences in those metrics. These results present possible future targets for MS management by increasing MVPA.

Cathepsin B and Muscular Strength are Independently Associated with Cognitive Control.

Although muscular strength has been linked to greater cognitive function across different cognitive domains, the mechanism(s) through which this occurs remain(s) poorly understood. Indeed, while an emerging body of literature suggests peripheral myokines released from muscular contractions may play a role in this relationship, additional research is needed to understand this link. Accordingly, this study sought to compare the influences of a particular myokine, Cathepsin B (CTSB), and muscular strength on hippocampal-dependent relational memory and cognitive control in 40 adults (age = 50.0±7.3 yrs). Overnight fasted venous blood draws were taken to assess plasma CTSB and muscular strength was assessed as maximal isokinetic strength testing using a Biodex dynamometer. Cognitive performance was assessed using a Spatial Reconstruction Task to assess relational memory and a modified Flanker task to assess cognitive control. Neuroelectric function for cognitive control was assessed using event-related potentials (ERPs) recorded during the Flanker task. Initial bivariate correlational analyses revealed that neither sex, age, lean body mass, or muscular strength was associated with CTSB. However, CTSB was inversely associated with reaction time and fractional peak latency of the P3 component of the Flanker task. Muscular strength was also inversely associated with reaction time and positively associated with relational memory performance. However, the influence of muscular strength on relational memory did not persist following adjustment for covariates. Greater circulating CTSB was selectively associated with greater cognitive control as well as faster information processing speed. These findings are the first to link circulating CTSB to both cognitive control and neuroelectric function. Future intervention studies are needed to examine the effects of changes in muscular strength, circulating myokines, and different domains of cognitive function.