Effects of ketone supplements on blood ß-hydroxybutyrate, glucose and insulin: A systematic review and three-level meta-analysis.

BACKGROUND: Effects of ketone supplements as well as relevant dose-response relationships and time effects on blood ß-hydroxybutyrate (BHB), glucose and insulin are controversial. OBJECTIVE: This study aimed to summarize the existing evidence and synthesize the results, and demonstrate underlying dose-response relationships as well as sustained time effects. METHODS: Medline, Web of Science, Embase, and Cochrane Central Register of Controlled Trials were searched for relevant randomized crossover/parallel studies published until 25th November 2022. Three-level meta-analysis compared the acute effects of exogenous ketone supplementation and placebo in regulating blood parameters, with Hedge's g used as measure of effect size. Effects of potential moderators were explored through multilevel regression models. Dose-response and time-effect models were established via fractional polynomial regression. RESULTS: The meta-analysis with 327 data points from 30 studies (408 participants) indicated that exogenous ketones led to a significant increase in blood BHB (Hedge's g = 1.4994, 95% CI [1.2648, 1.7340]), reduction in glucose (Hedge's g = -0.3796, 95% CI [-0.4550, -0.3041]), and elevation in insulin of non-athlete healthy population (Hedge's g = 0.1214, 95%CI [0.0582, 0.3011]), as well as insignificant change in insulin of obesity and prediabetes. Nonlinear dose-response relationship between ketone dosage and blood parameter change was observed in some time intervals for BHB (30-60 min; >120 min) and insulin (30-60 min; 90-120 min), with linear relationship observed for glucose (>120 min). Nonlinear associations between time and blood parameter change were found in BHB (>550 mg/kg) and glucose (450-550 mg/kg), with linear relationship observed in BHB (≤250 mg/kg) and insulin (350-550 mg/kg). CONCLUSION: Dose-response relationships and sustained time effects were observed in BHB, glucose and insulin following ketone supplementation. Glucose-lowering effect without increasing insulin load among population of obesity and prediabetes was of remarkable clinical implication. REGISTRY AND REGISTRY NUMBER: PROSPERO (CRD42022360620).

Neurobehavioral mechanisms underlying the effects of physical exercise break on episodic memory during prolonged sitting.

BACKGROUND AND OBJECTIVE: Episodic memory is the ability that enables individuals to recall and re-experience previous events and usually includes information concerning the spatial and temporal context. This study examined the effects of a physical exercise break during a period of prolonged sitting on episodic memory. Furthermore, we aimed to investigate whether alterations of functional connectivity patterns might contribute to the exercise-induced changes in episodic memory. METHODS: Sixty healthy male college students were randomly assigned (1:1 ratio) to a prolonged-sitting group (PS group) or a physical-exercise-break group (PE group). The face-name paired-associate learning task was used to probe episodic memory. During the task, cortical hemodynamics in the prefrontal cortex were recorded using functional near-infrared spectroscopy (fNIRS). Changes in cortical hemodynamics were used to determine functional connectivity using graph-theoretical network analysis. RESULTS: There was no between-group difference in neurobehavioral outcomes at the pretest assessment. During the posttest assessment, compared with the PS group, higher nodal efficiency in the anterior prefrontal cortex (orbitofrontal and frontopolar cortices) was observed during the encoding phase (FDR corrected p values = 0.039), and higher nodal efficiency and degree centrality of orbitofrontal cortex were observed in the retrieval phase in the PE group (FDR corrected p values = 0.035). Moreover, the PE group showed closer temporal correlational interactions between the dorsolateral prefrontal cortex and the anterior prefrontal cortex in the left hemisphere during the episodic memory encoding phase (FDR corrected p values = 0.043), when compared to the PS group. Neither significant between-group difference in accuracy nor correlations between neural and behavioral outcomes were observed after the intervention. CONCLUSION: Our findings suggest that a physical exercise break during a prolonged sitting period has neither a beneficial nor a detrimental effect on behavioral performance concerning episodic memory. However, physical breaks do facilitate functional connectivity patterns of the prefrontal cortex while performing a episodic memory task.

Effects of Basketball and Baduanjin Exercise Interventions on Problematic Smartphone Use and Mental Health among College Students: A Randomized Controlled Trial.

Problematic smartphone use (PSU) has become a prevalent issue worldwide. Previous studies suggest that physical exercising may effectively reduce smartphone users' addiction levels. Comparisons and further evaluations on the long-term effects of different types of exercise-based interventions on treating PSU remain to be investigated. Objective. We investigated if group-based basketball and Baduanjin exercise (a type of Qigong) would reduce PSU and improve the mental health of college students and whether such effects would be sustained. A twelve-week experiment was conducted, where 96 eligible Chinese college students with PSU were randomly assigned to two intervention arms (i.e., basketball and Baduanjin exercises) and a control arm. Outcome measures, including PSU (measured by the Mobile Phone Addiction Index in Chinese (MPAI)) and mental health indices for anxiety (measured by Self-Rating Anxiety Scale (SRAS)), loneliness (measured by the short-form of the UCLA Loneliness Scale (UCLA-LS)), inadequacy (measured by the revised Janis and Field's Feelings of Inadequacy Scale (FIS)), and stress (measured by the Chinese version of Perceived Stress Scale (CPSS)) were collected at the baseline, the end of week 12, and the two-month follow-up. A Generalized Estimating Equations (GEE) model for longitudinal data was utilized in analyses. Results. Both exercise interventions demonstrated significant effects on decreasing PSU (basketball: p < 0.01; Baduanjin: p < 0.01), feelings of anxiety (basketball: p < 0.01; Baduanjin: p=0.04), loneliness (basketball: p < 0.01; Baduanjin: p < 0.01), inadequacy (basketball: p < 0.01; Baduanjin: p < 0.01), and perceived stress (basketball: p < 0.01; Baduanjin: p=0.04), at the end of interventions. At two months after interventions, both exercise interventions demonstrated significant effects on decreasing PSU (basketball: p < 0.05; Baduanjin: p < 0.05), feelings of anxiety (basketball: p < 0.01; Baduanjin: p=0.03), loneliness (basketball: p < 0.01; Baduanjin: p < 0.01), and inadequacy (basketball: p < 0.01; Baduanjin: p=0.01), but not for feeling of stress. Furthermore, group-based basketball demonstrated larger improvements for all these significant results on reducing PSU and meanwhile improving their related mental health parameters among college students.

Regular Tai Chi Practice Is Associated With Improved Memory as Well as Structural and Functional Alterations of the Hippocampus in the Elderly.

OBJECTIVE: The current study aimed at comparing the effects of Tai Chi (a motor-cognitive exercise) with walking (an exercise without cognitive demands) on cognitive performance, brain structure, and brain function in the elderly. METHODS: This cross-sectional study included 42 healthy elderly women within two groups: Tai Chi (n = 20; mean age = 62.90 ± 2.38 years) and brisk walking exercise (n = 22; mean age = 63.27 ± 3.58 years). All the participants underwent a cognitive assessment via the Montreal Cognitive Assessment and brain structural and resting state functional magnetic resonance imaging (rsfMRI) assessments. RESULTS: Episodic memory in the Tai Chi group was superior to that of the walking group. Higher gray matter density in the inferior and medial temporal regions (including the hippocampus) and higher ReHo in temporal regions (specifically the fusiform gyrus and hippocampus) were found in the Tai Chi group. Significant partial correlations were found between the gray matter density of the left hippocampus and episodic memory in the whole sample. Significant partial correlations were observed between the ReHo in left hippocampus, left parahippocampal, left fusiform, and delayed memory task, which was observed among all subjects. CONCLUSION: The present study suggests that long-term Tai Chi practice may improve memory performance via remodeling the structure and function of the hippocampus.

Superior Effects of Modified Chen-Style Tai Chi versus 24-Style Tai Chi on Cognitive Function, Fitness, and Balance Performance in Adults over 55.

BACKGROUND: Cognitive decline and balance impairment are prevalent in the aging population. Previous studies investigated the beneficial effects of 24-style Tai Chi (TC-24) on either cognitive function or balance performance of older adults. It still remains largely unknown whether modified Chen-style TC (MTC) that includes 18 complex movements is more beneficial for these age-related health outcomes, as compared to TC-24. OBJECTIVE: We investigated if MTC would show greater effects than TC-24 on global cognitive function and balance-related outcomes among older adults. METHODS: We conducted a randomized trial where 80 eligible adults aged over 55 were allocated into two different styles of Tai Chi (TC) arms (sixty-minute session × three times per week, 12 weeks). Outcome assessments were performed at three time periods (baseline, Week 6, and Week 12) and included the Chinese Version of the Montreal Cognitive Assessment (MoCA) for overall cognitive function, One-leg Standing Test (LST) for static balance, Timed Up and Go Test (TUGT) for dynamic balance, chair Stand Test (CST) for leg power, and the six-meter Walk Test (6MWT) for aerobic exercise capacity. RESULTS: Compared to TC-24 arm, MTC arm demonstrated significantly greater improvements in MoCA, LST, TUGT, CST, and 6MWT (all p < 0.05). CONCLUSIONS: Both forms of TC were effective in enhancing global cognitive function, balance, and fitness. Furthermore, MTC was more effective than TC-24 in enhancing these health-related parameters in an aging population.

Tai Chi as an Alternative Exercise to Improve Physical Fitness for Children and Adolescents with Intellectual Disability.

OBJECTIVE: The purpose of this study was to investigate the effects of Tai Chi (TC) on anthropometric parameters and physical fitness among children and adolescents with intellectual disabilities (ID). METHODS: Sixty-six Chinese individuals engaged in sport-related extracurricular activities (TC and aerobic exercise (AE)) as exercise interventions or arts/crafts activities as a control condition (CON). The experimental protocol consisted of a baseline assessment, a 12-week intervention period, and a post-intervention assessment. RESULTS: Significant interaction effect was only observed in the performance of a 6-min walk test. After 12 weeks of intervention, the AE group had significant changes in body mass index (p = 0.006, d = 0.11), sit-ups (p = 0.030 and d = 0.57), and 6-min walk test (p = 0.005, d = 0.89). Significant increases in vertical jump (p = 0.048, d = 0.41), lower-limb coordination (p = 0.008, d = 0.53), and upper-limb coordination (p = 0.048, d = 0.36) were observed in the TC group. Furthermore, the TC group demonstrated significantly greater improvements on balance compared to the control group (p = 0.011). CONCLUSIONS: TC may improve leg power and coordination of both lower and upper limbs, while AE may be beneficial for body mass index, sit-ups and cardiorespiratory fitness.

The Effects of Tai Chi on Markers of Atherosclerosis, Lower-limb Physical Function, and Cognitive Ability in Adults Aged Over 60: A Randomized Controlled Trial.

Objective: The purpose of this study was to investigate the effects of Tai Chi (TC) on arterial stiffness, physical function of lower-limb, and cognitive ability in adults aged over 60. Methods: This study was a prospective and randomized 12-week intervention trial with three repeated measurements (baseline, 6, and 12 weeks). Sixty healthy adults who met the inclusion criteria were randomly allocated into three training conditions (TC-24, TC-42, and TC-56) matched by gender, with 20 participants (10 males, 10 females) in each of the three groups. We measured the following health outcomes, including markers of atherosclerosis, physical function (leg power, and static and dynamic balance) of lower-limb, and cognitive ability. Results: When all three TC groups (p < 0.05) have showed significant improvements on these outcomes but overall cognitive ability at 6 or 12 weeks training period, TC-56 appears to have superior effects on arterial stiffness and static/dynamic balance in the present study. Conclusions: Study results of the present study add to growing body of evidence regarding therapeutic TC for health promotion and disease prevention in aging population. Future studies should further determine whether TC-42 and TC-56 are beneficial for other non-Chinese populations, with rigorous research design and follow-up assessment.

Qigong-Based Therapy for Treating Adults with Major Depressive Disorder: A Meta-Analysis of Randomized Controlled Trials.

This current meta-analysis review was conducted to examine the effectiveness of Qigong-based therapy on individuals with major depressive disorder. Six electronic databases (PubMed, PsycINFO, Cochrane Library, and Web of Science, Chinese National Knowledge Infrastructure, and Wangfang) were employed to retrieve potential articles that were randomized controlled trials. The synthesized effect sizes (Hedges' g) were computerized to explore the effectiveness of Qigong-based therapy. Additionally, a moderator analysis was performed based on the control type. The pooled results indicated that Qigong-based therapy has a significant benefit on depression severity (Hedges' g = -0.64, 95% CI -0.92 to -0.35, p < 0. 001, I² = 41.73%). Specifically, Qigong led to significantly reduced depression as compared to the active control groups (Hedges' g = -0.47, 95% CI -0.81 to -0.12, p = 0.01, I² = 22.75%) and the passive control groups (Hedges' g = -0.80, 95% CI -1.23 to -0.37, p < 0.01, I² = 48.07%), respectively. For studies which reported categorical outcomes, Qigong intervention showed significantly improved treatment response rates (OR = 4.38, 95% CI 1.26 to 15.23, p = 0.02) and remission rates (OR = 8.52, 95% CI 1.91 to 37.98, p = 0.005) in comparison to the waitlist control group. Conclusions: Qigong-based exercises may be effective for alleviating depression symptoms in individuals with major depressive disorder. Future well-designed, randomized, controlled trials with large sample sizes are needed to confirm these findings.

Chen-Style Tai Chi for Individuals (Aged 50 Years Old or Above) with Chronic Non-Specific Low Back Pain: A Randomized Controlled Trial.

Tai Chi (TC) can be considered safe and effective intervention to improve pain and pain-related functional disability. However, it is unclear that whether aging individuals with Chronic Non-Specific Low Back Pain (CNS-LBP) can achieve positive results. This study, therefore, attempted to explore the effects of TC on pain and functional disability in CNS-LBP patients aged 50 years old or above. Forty-three individuals (aged 50 years old or above) with CNS-LBP were randomly assigned into three groups: Chen-Style TC group (n = 15), Core Stabilization training (CST) group (n = 15), and control group (n = 13). Participants in the TC group participated in Chen-style TC training program (three 60-min sessions per week for 12 weeks), individuals in CST group received 12-week Core Stabilization exercise on the Swiss ball, whereas individuals in the control group maintained their unaltered lifestyle. Pain intensity as primary outcome was measured using the Visual Analogue Scale (VAS), A BiodexSystem 3 isokinetic dynamometer was used to measure knee and ankle joint position sense (JPS) as secondary outcomes at baseline and after the 12-week intervention. TC and CST have significant effects in VAS for CNS-LBP patients (p< 0.01, TC group OR CST group versus control group in mean of the post-minus-pre assessment). However, the feature of joint position sense (JPS) of ankle inversion, ankle eversion and knee flexion did not occur, it showed no significant effects with TC and CST. TC was found to reduce pain, but not improve lower limb proprioception in patients with CNS-LBP. Future research with larger sample sizes will be needed to achieve more definitive findings on the effects of TC on both pain and lower limb proprioception in this population.

Mind-Body Exercise (Wuqinxi) for Patients with Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Objective: This study is the first meta-analysis investigating the rehabilitative effects of Wuqinxi for patients with chronic obstructive pulmonary disease (COPD). Methods: Five electronic databases (PubMed, Web of Science, Scopus, CNKI, and Wanfang) from inception until early November 2018 were searched. All randomized controlled trials (RCT) using Wuqinxi as the main intervention component were included for meta-analysis. The pooled effect sizes (Standardized mean difference, SMD) were calculated to determine the magnitude of the Wuqinxi intervention effect. Moderator analysis was only conducted for total training time. Results: Overall results of the meta-analysis indicated that Wuqinxi exercise significantly improved exercise capability (SMD = 1.18, 95% CI 0.53 to 1.84, e < 0.001, I² = 84.97%), FEV1 (SMD = 0.44, 95% CI 0.12 to 0.77, e < 0.001, I² = 33.77%), FEV1% (SMD = 0.59, 95% CI 0.24 to 0.93, e < 0.001, I² = 63.79%), FEV1/FVC (SMD = 0.65, 95% CI 0.37 to 0.93, e = 0.006, I² = 44.32%) and CCQ (SMD = 1.23, 95% CI 0.31 to 2.14, e = 0.01, I² = 93.32%). Conclusions: With no occurrence of adverse event, clinicians could try to incorporate Wuqinxi exercise into their first-line rehabilitation regime for COPD patients.