High-intensity interval training and cardiorespiratory fitness in adults: An umbrella review of systematic reviews and meta-analyses.

BACKGROUND: High-intensity interval training (HIIT) is characterized by repeated bouts of relatively intense exercise interspersed with recovery periods. Previous studies have evaluated this exercise strategy with various population subgroups, regimens, and comparator groups, limiting the generalizability of findings. We performed a novel umbrella review to generate an up-to-date synthesis of the available evidence regarding the effect of HIIT on cardiorespiratory fitness (CRF) in adults as compared to non-exercise control and traditional continuous forms of exercise such as moderate-intensity continuous training (MICT). METHODS: An umbrella review was conducted in accordance with the Preferred Reporting Items for Overviews of Reviews guideline. Seven databases (MEDLINE, EMBASE, Cochrane Database, CINAHL, Scopus, SPORTDiscus, and Web of Science) were searched until February 2024. Systematic reviews with meta-analyses comparing HIIT and active/non-active control conditions were included. Literature search, data extraction, and methodological quality assessment (AMSTAR-2) were conducted independently by two reviewers. RESULTS: Twenty-four systematic reviews with meta-analyses, representing 429 primary studies and 12 967 unique participants, met the inclusion criteria. Most of the systematic reviews received moderate-to-critically low AMSTAR-2 scores. The data showed that HIIT, including the particularly intense variant "sprint interval training" (SIT), significantly increases CRF in adults compared to non-exercise control (standardized mean difference [SMD]: 0.28 to 4.31; weighted mean difference [WMD]: 3.25 to 5.5 mL/kg/min) and MICT (SMD: 0.18 to 0.99; WMD: 0.52 to 3.76 mL/kg/min). This effect was consistently observed across specific groups of individuals (e.g., apparently healthy adults, individuals with overweight/obesity, older adults, and high-level athletes) and HIIT modalities (e.g., low-volume HIIT, whole-body HIIT, home-based HIIT, aquatic HIIT, and short SIT). CONCLUSION: Existing evidence from systematic reviews consistently supports the effect of HIIT on enhancing CRF in adults when compared to non-exercise control and MICT. Our findings offer a comprehensive basis that may potentially contribute to informing physical activity guidelines aimed at improving CRF in the general population.

Active video game on children and adolescents' physical activity and weight management: A network meta-analysis.

We synthesized evidence on the effectiveness of active video games (AVGs) versus no AVG-applied comparators on various physical activity (PA) levels and weight management outcomes in children and adolescents. We analyzed the comparative evidence on different sub-categories of AVGs and ranking the best option. An overview of systematic reviews (SRs) and network meta-analysis (NMA) (PROSPERO: CRD42021248499) was employed. A search for relevant literature published in English was conducted in six electronic databases from their inception until April 2021. SRs consisting of randomized control trials (RCTs) and satisfying our PICOS inclusion criteria were included. RCTs included were a comparison of groups among children and adolescents between 6 and 21, where groups with AVG interventions were compared with groups without them. Direct head-to-head pairwise meta-analyses were conducted using weighted mean difference between the two groups, and the comparative effectiveness of different sub-categories of AVGs was analyzed indirectly using NMA. Overall, 17 SRs were identified from the 6036 screened citations. Of these, 350 citations were retrieved, and 12 RCTs were finally included. Compared with no AVG group, AVG groups were shown to be more effective in achieving vigorous, moderate-to-vigorous, and moderate PA levels, and decreased BMI and body fat. NMA showed that rhythmic dance games had the highest probability of being the most effective sub-category for reducing BMI. AVGs are effective in attaining vigorous, moderate to vigorous, and moderate PA levels, and reducing BMI and body fat among children and adolescents. Dance appears to be the best option for reducing BMI among AVG subcategories.

Relationships of physical activity and sedentary behaviour with the previous and subsequent nights' sleep in children and youth: A systematic review and meta-analysis.

The interrelationships between sleep and daytime movement behaviours have been examined at interindividual level. Studies of within-person, temporal relationships of daytime physical activity (PA) and sedentary behaviour with the previous and subsequent nights' sleep are increasing. The present systematic review and meta-analysis synthesised the results of studies in school-aged children and youth. Eight databases (MEDLINE, PsycINFO, EMBASE, Global Health, PubMed, Web of Science, SPORTDiscus, and CINAHL) were searched for peer-reviewed articles that examined the association between daytime movement behaviours (including PA, sedentary time, or sedentary recreational screen time) and night-time sleep on the same day, or the association between night-time sleep and daytime movement behaviours the next day, in children and youth. A total of 11 studies comprising 9,622 children and youth aged 5-15 years met the inclusion criteria. Sedentary time was negatively associated with the subsequent night's sleep duration (r = -0.12, 95% confidence interval -0.23 to -0.00; I2  = 93%; p = .04). Positive relationships between PA and the previous or subsequent night's sleep duration were observed only for studies that adjusted for accelerometer wear time. There was some evidence suggesting that a longer sleep duration was associated with less sedentary time and a higher proportion of the daytime spent being physically active and vice versa, although the association was weak and based on a limited number of studies. From a clinical perspective, promotion of either sleep hygiene or daytime PA should be planned with considerations of the virtuous or vicious circle between these behaviours and monitor concurrent effects on the others.

Effect of sedentary behavior interventions on vascular function in adults: A systematic review and meta-analysis.

Sedentary behavior (SB) results in hemodynamic alterations within the vasculature, leading to vascular dysfunction that may be attenuated by various interventions. This systematic review and meta-analysis examined the effect of SB interventions on vascular function in adults using seven databases searched on December 17, 2020. All types of SB interventions were included such as short- and long-term interventions (≥7 days) in participants aged ≥18 years. The pooled effect (mean difference) of intervention on three outcomes, namely, flow-mediated dilation (FMD), shear rate (SR), and pulse wave velocity (PWV), was evaluated using random effects meta-analyses. The revised Cochrane risk-of-bias tool for randomized trials was employed to assess the quality of the included studies. Twenty-six studies (21 short-term and six long-term interventions) involving 669 participants from eight countries were included. Evidence from meta-analysis showed that short-term interventions targeting SB improved FMD by 1.50% (95% confidence interval [CI] 1.00-1.99) and increased SR by 12.70 S-1 (95% CI 7.86-17.54); no significant pooled effect was found for PWV. Long-term SB interventions resulted in a 0.93% increase in FMD (95% CI 0.25-1.62) and had no significant effect on PWV. Findings of this systematic review and meta-analysis suggest that both short- and long-term SB interventions improved FMD but had no effect on PWV. Short-term interventions had a greater effect in improving lower extremity arterial function. Further studies targeting long-term SB interventions on vascular function in adults are warranted.

Interval training versus moderate-intensity continuous training for cardiorespiratory fitness improvements in middle-aged and older adults: a systematic review and meta-analysis.

Interval training has been promoted as a superior, time-efficient exercise strategy for enhancing cardiorespiratory fitness in the ageing population. This study assessed the effectiveness of interval training compared with that of moderate-intensity continuous training (MICT) for improving cardiorespiratory fitness in middle-aged and older adults. Six databases were systematically searched for studies with exercise interventions (minimum 2-week duration). Meta-analyses were conducted for within-group and between-group comparisons of maximal oxygen uptake (VO2max). Sub-group analysis was performed using the nature of interval training (high-intensity interval training [HIIT] and sprint interval training [SIT]). Of 3,257 studies, 14 were included (429 participants). Within-group analyses demonstrated significant VO2max improvements (mL/kg/min) following interval training (mean difference: MD = 2.26; 95% confidence interval [CI] = 1.50-3.02) and MICT (MD = 1.34; 95% CI = 0.45-2.23]. When comparing the modes of training, the gain in VO2max was significantly greater following interval training (MD = 1.10; CI = 0.55-1.64). Sub-group analysis showed that HIIT (MD = 1.04; CI = 0.21-1.88) and SIT (MD = 1.18; CI = 0.60-1.76) resulted in superior VO2max gain than MICT. This study provides evidence synthesis for interval training as a viable exercise strategy to improve cardiorespiratory function in healthy ageing.

The Effect of Time-Restricted Eating Combined with Exercise on Body Composition and Metabolic Health: A Systematic Review and Meta-Analysis.

BACKGROUND: Time-restricted eating (TRE) is increasingly popular, but its benefits in combination with exercise still need to be determined. OBJECTIVES: This systematic review and meta-analysis aimed to evaluate the efficacy of TRE combined with exercise compared with control diet with exercise in improving the body composition and metabolic health of adults. METHODS: Five electronic databases were searched for relevant studies. Randomized controlled trials (RCTs) examining the effect of TRE combined with exercise on body composition and metabolic health in adults were included. All results in the meta-analysis are reported as mean difference (MD) with 95% confidence interval (CI). Study quality was assessed using the revised Cochrane Risk of Bias Tool and Grading of Recommendations Assessment, Development, and Evaluation assessment. RESULTS: In total, 19 RCTs comprising 568 participants were included in this systematic review and meta-analysis. TRE combined with exercise likely reduced the participants' body mass (MD: -1.86 kg; 95% CI: -2.75, -0.97 kg) and fat mass (MD: -1.52 kg; 95% CI: -2.07, -0.97 kg) when compared with the control diet with exercise. In terms of metabolic health, the TRE combined with exercise group likely reduced triglycerides (MD: -13.38 mg/dL, 95% CI: -21.22, -5.54 mg/dL) and may result in a reduction in low-density lipoprotein (MD: -8.52 mg/dL; 95% CI: -11.72, -5.33 mg/dL) and a large reduction in leptin (MD: -0.67 ng/mL; 95% CI: -1.02, -0.33 ng/mL). However, TRE plus exercise exhibited no additional benefit on the glucose profile, including fasting glucose and insulin, and other lipid profiles, including total cholesterol and high-density lipoprotein concentrations, compared with the control group. CONCLUSIONS: Combining TRE with exercise may be more effective in reducing body weight and fat mass and improving lipid profile than control diet with exercise. Implementing this approach may benefit individuals aiming to achieve weight loss and enhance their metabolic well-being. This study was registered in PROSPERO as CRD42022353834.

Methodological Quality of Systematic Reviews on Bodyweight Management Strategies for Children and Adolescents.

INTRODUCTION: Systematic reviews (SRs) synthesize empirical evidence from randomized controlled trials, to answer a research question. Methodological flaws in SRs can, however, reduce the trustworthiness of conclusions, subsequently hindering decision making. We aimed to appraise the methodological quality of existing SRs on bodyweight management strategies for children and adolescents. METHODS: We searched Cochrane Database of Systematic Reviews, MEDLINE, EMBASE, and SPORTDiscus. A MeaSurement Tool to Assess systematic Reviews (AMSTAR 2) was used to evaluate the methodological quality of SRs including 16 individual AMSTAR 2 domains and the total AMSTAR score. Association between bibliographical characteristics and total AMSTAR score of SRs was explored using multiple linear regression analysis. RESULTS: Three critical domain-specific items of AMSTAR 2 among the included SRs showed unsatisfactory results including (i) justifying deviation from their SR protocols, (ii) using comprehensive literature search strategies, and (iii) giving details of both included and excluded studies. "More recent publication year journal," "higher impact factor of the journal," and "greater number of review authors" were associated with better methodological quality of the included SRs. CONCLUSIONS: Future SRs' authors in the field of bodyweight management strategies for children and adolescents should improve the following criteria: (i) justify deviations from SR protocol, (ii) explain selection of the included study designs, (iii) use comprehensive literature search strategy, (iv) give details for both included and excluded studies, (v) report funding sources among included studies, and (vi) assess the potential impact of risk of bias among the included studies on meta-analysis results.

Parental Factors Associated With Physical Activity Among East Asian Children/Youth: A Meta-Analysis Based on the Active Healthy Kids Report Cards.

Insufficient physical activity (PA) is a leading risk factor for mortality. The Active Healthy Kids Report Cards provide comprehensive evidence related to PA in children/adolescents. Associations of (1) parental support for PA with amount of moderate-to-vigorous-intensity PA (MVPA) performed by children/adolescents and (2) amount of MVPA performed by parents with amount of MVPA performed by children/adolescents, as indicated by Report Cards, have not been critically synthesized in meta-analysis. We selected data in Asian countries/regions Report Cards and performed meta-analyses to assess pooled associations of influence indicators and behavior indicators among children/adolescents in Asian countries/regions. Our meta-analyses included five studies that assessed association of parental support or MVPA performance with child/adolescent MVPA performance. Positive association was observed between the amount of time spent by parents on MVPA per week, regardless of gender, and the amount of time spent by children and adolescents on MVPA per week (r = .11; I2 = 40%). In East Asia, the amount of MVPA performed by parents appears to be an important factor influencing the participation of children/adolescents in PA.