Effects of time-restricted feeding and walking exercise on the physical health of female college students with hidden obesity: a randomized trial

Comparative efficacy of different exercise types on body composition in university students: a systematic review and meta-analysis of randomized controlled trials

Background

To systematically assess the impact of various exercise modalities and dosages on the body composition of college students through a comprehensive review of randomized controlled trials (RCTs).

Methods

We conducted a comprehensive search of relevant randomized controlled trials (RCTs) in eight databases, covering data from the inception of each database to August 2024. Following the literature screening, two investigators independently conducted data extraction and assessed the risk of bias. Network meta-analysis (NMA) was conducted using Stata 17.0 with random-effects modeling, while dose-response analysis was performed utilizing R version 4.3.1.

Results

A total of 43 randomized controlled trials (RCTs), encompassing 3,154 participants, were included in the analysis. Aerobic exercise, combined exercise, high-intensity interval training (HIIT), mind-body exercise, and calisthenics demonstrated significant effects on reducing body mass index (BMI) compared to control groups. Surface under the cumulative ranking (SUCRA) probability rankings indicated that calisthenics had the highest likelihood of being the most effective intervention for BMI reduction, whereas resistance exercise was associated with the lowest likelihood. The dose-response analysis revealed that the threshold exercise dose for overall exercise to lower BMI was 310 METs-min/week, with the predicted maximum significant response dose being 1,300 METs-min/week, beyond which there was minimal change in the intervention effect. Additionally, distinct nonlinear dose-response relationships were observed for aerobic exercise, combined exercise, HIIT, mind-body exercise, and aerobics.

Conclusion

No significant differences in the effectiveness of exercise interventions on body composition were observed across exercise types. However, based on the SUCRA analysis, calisthenics emerged as the preferred intervention, succeeded by a combination of exercises. The optimal exercise dosage for enhancing body composition was identified as 1,300 METs-min/week, with the threshold for a significant effect being relatively low.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/view/CRD42024587032.

The Association Between Chronotype and Weight Change Among Medical Students: A Cross-Sectional Study

Purpose

This study analyzed the differences in weight change among medical students with different chronotypes and evaluated the association between chronotype and weight change after controlling for confounders.

Methods

Using proportional stratified cluster random sampling, 1300 medical students (excluding freshmen) were selected from April to September 2021. Chronotype was assessed with the Chinese version of MEQ-5 questionnaire, categorized into five groups: definite morning, moderate morning, intermediate, moderate evening, and definite evening. The primary outcome was weight change value (kg), the difference between current weight and weight at admission; the secondary outcome was weight gain (≥10% increase from admission weight). Multiple linear and logistic regression models were used to analyze the independent association between chronotype, weight change value, and weight gain, respectively.

Results

Among the 1300 medical students, the proportion of definite morning, moderate morning, intermediate, moderate evening, and definite evening chronotype were 14.08%, 12.38%, 28.92%, 31.46%, 13.15%, respectively. Definite evening-type students had worse sleep quality, shorter sleep duration, more late-night snacks, higher satiety, and lower breakfast frequency (P<0.05). Compared to definite morning-type medical students, those with moderate morning, intermediate, moderate evening and definite evening chronotype showed an increasing trend of weight change (P=0.044), with definite evening-type students gaining 0.88 kg on average (95% CI: 0.10, 1.65), consistent after adjusting for confounders. The association between chronotype and weight gain was similar although not statistically significant (OR=1.96, 95% CI: 0.72, 5.36). Evening chronotype with dinner ≥ 6 PM had the highest odds of weight gain compared to morning chronotype with dinner before 6 PM (OR=2.43, 95% CI: 1.07, 5.50).

Conclusion

Definite evening chronotype was associated with greater weight increase and higher odds of weight gain among medical students, especially when dinner ≥ 6 PM. These findings highlight the importance of morning chronotype and early dinner for weight control.

Effects of exercise combined with different dietary interventions on cardiovascular health a systematic review and network meta-analysis

BACKGROUND

Numerous studies have shown that exercise and dietary interventions positively impact CVD outcomes; however, there is substantial variability in the efficacy of different interventions. The absence of direct comparisons between multiple interventions complicates the determination of their relative effects. This study aims to synthesize the literature on the impacts of exercise, dietary, and combined interventions on cardiovascular health indicators, and to perform a network meta-analysis to rank the efficacy of these approaches, providing a theoretical foundation for selecting optimal intervention strategies.

METHODS

We systematically reviewed the literature from database inception through September 2024, searching PubMed, Web of Science, Embase, and the Cochrane Library. Data were aggregated and analyzed using network meta-analysis, with intervention efficacy ranked according to Surface Under the Cumulative Ranking (SUCRA) curves.

RESULTS

The efficacy of these interventions was ranked as follows: 1). Triglycerides (TG) Reduction: CR + EX > CR > 5/2F + EX > TRF + EX > KD > 5/2F > KD + EX > EX > CON > TRF. 2). Total Cholesterol (TC) Reduction: CR + EX > CR > 5/2F + EX > 5/2F > TRF + EX > EX > CON > KD > TRF > KD + EX. 3). High-Density Lipoprotein (HDL) Increase: 5/2F > KD > KD + EX > TRF + EX > CON > EX > TRF > 5/2F + EX > CR + EX > CR. 4). Low-Density Lipoprotein (LDL) Reduction: CR + EX > CR > TRF + EX > KD + EX > EX > KD > 5/2F > CON > 5/2F + EX > TRF. 5). Systolic Blood Pressure (SBP) Reduction: 5/2F > CR + EX > CR > EX > TRF > TRF + EX > CON > 5/2F + EX. 6). Diastolic Blood Pressure (DBP) Reduction: CR > CR + EX > TRF > 5/2F > TRF + EX > EX > CON > 5/2F + EX.

CONCLUSION

CR and CR + EX demonstrated the most positive effects on cardiovascular health indicators. In contrast, 5/2F + EX ranked relatively low in effectiveness, with its impact on several indicators being even lower than that of CON.

Intermittent fasting as a treatment for obesity in young people: a scoping review

Intermittent fasting focuses on the timing of eating rather than diet quality or energy intake, with evidence supporting its effects on weight loss and improvements in cardiometabolic outcomes in adults with obesity. However, there is limited evidence for its feasibility and efficacy in young people. To address this, a scoping review was conducted to examine intermittent fasting regimens in individuals aged 10 to 25 for the treatment of obesity focusing on methodology, intervention parameters, outcomes, adherence, feasibility, and efficacy. Due to the paucity of evidence in this age group, to adequately assess feasibility and adherence, all published studies of intermittent fasting in this age category, regardless of weight status and treatment intention, were included in the review. The review included 34 studies (28 interventional studies and 6 observational studies) with 893 participants aged 12 to 25. Interventions varied with 9 studies in cohorts with obesity utilizing intermittent fasting as an obesity treatment. Thirteen studies utilized 8-h time-restricted eating. Primary outcomes included cardiometabolic risk factors (7/28), anthropometric measurements (7/28), body composition (5/28), muscular performance (4/28), feasibility (1/28), and others (4/28). All 9 studies conducted in young people with obesity reported some degree of weight loss, although the comparator groups varied significantly. This review underscores the various utilizations of intermittent fasting in this age group and highlights its potential in treating obesity. However, the findings emphasize the need for rigorous studies with standardized frameworks for feasibility to ensure comparability and determine intermittent fasting's practicality in this age group depending on the treatment outcome of interest.

Evaluating the efficacy of intermittent fasting and exercise combinations for weight loss: A network meta-analysis

OBJECTIVE

The purpose of this study is to utilize network meta-analysis (NMA) to synthesize relevant randomized controlled trials (RCTs) and evaluate the most effective intermittent fasting (IF) combined with exercise interventions for weight loss.

METHODS

This study searched five databases up until April 2024, obtaining RCTs that investigated the effects of intermittent fasting (IF) combined with exercise. The quality of the literature was assessed using the Cochrane tool, followed by a random-effects statistical analysis of each intervention. Eventually, a NMA was conducted to compare the effectiveness of each intervention on weight loss, thereby determining their combined effectiveness on reducing weight.

RESULTS

A total of nine trials, comparing 12 interventions involving 570 participants, were included. All interventions significantly reduced body weight (BW) and fat mass (FM) compared to the control (CON) group. In terms of BW reduction, the alternate-day fasting + moderate-intensity continuous training (ADF + MICT) intervention had the highest surface under the cumulative ranking curve average (SUCRA) score 88.1(MD: -4.44,95% CI -5.95, -2.92). Furthermore, for improving FM, the ADF + MICT intervention also had the highest SUCRA score 92.7(MD: -3.65,95% CI -5.05, -2.25), making it the optimal intervention for improving FM.

CONCLUSION

The NMA results indicate that all interventions are effective in reducing weight. Among them, ADF + MICT is the most effective strategy for reducing BW, and it is also the best approach for improving FM.

Comparing caloric restriction regimens for effective weight management in adults: a systematic review and network meta-analysis

BACKGROUND

Randomized controlled trials have confirmed the effectiveness of four prevalent caloric restriction regimens in reducing obesity-related health risks. However, there is no consensus on the optimal regimen for weight management in adults.

METHODS

We systematically searched PubMed, Embase, Web of Science, and Cochrane CENTRAL up to January 15, 2024, for randomized controlled trials (RCT) involving adults, evaluating the weight-loss effects of alternate day fasting (ADF), short-term fasting (STF), time-restricted eating (TRE), and continuous energy restriction (CER). The primary outcome was body weight, with secondary outcomes including BMI, fat mass, lean mass, waist circumference, fasting glucose, HOMA-IR, and adverse events. Bayesian network meta-analysis was conducted, ranking regimens using the surface under the cumulative ranking curve and the probability of being the best. Study quality was assessed using the Confidence in Network Meta-Analysis tool.

RESULTS

Data from 47 RCTs (representing 3363 participants) were included. ADF showed the most significant body weight loss (Mean difference (MD): -3.42; 95% Confidence interval (CI): -4.28 to -2.55), followed by TRE (MD: -2.25; 95% CI: -2.92 to -1.59). STF (MD: -1.87; 95% CI: -3.32 to -0.56) and CER (MD: -1.59; 95% CI: -2.42 to -0.79) rank third and fourth, respectively. STF lead to decline in lean mass (MD: -1.26; 95% CI: -2.16, -0.47). TRE showed benefits on fasting glucose (MD: -2.98; 95% CI: -4.7, -1.26). Subgroup analysis revealed all four caloric restriction regimens likely lead to modest weight loss after 1-3 months, with ADF ranked highest, but by 4-6 months, varying degrees of weight regain occur, particularly with CER, while interventions lasting 7-12 months may result in effective weight loss, with TRE potentially ranking first during both the 4-6 months and 7-12 months periods. ADF showing fewer and shorter-lasting physical symptoms.

CONCLUSION

All four included regiments were effective in reducing body weight, with ADF likely having the most significant impact. Each regimen likely leads to modest weight loss after 1-3 months, followed by weight regain by 4-6 months. However, interventions lasting 7-12 months achieve greater weight loss overall.

TRIAL REGISTRATION

PROSPERO: CRD42022382478.

Effects of Different Exercises Combined with Different Dietary Interventions on Body Composition: A Systematic Review and Network Meta-Analysis

BACKGROUND

Exercise and dietary interventions are essential for maintaining weight and reducing fat accumulation. With the growing popularity of various dietary strategies, evidence suggests that combining exercise with dietary interventions offers greater benefits than either approach alone. Consequently, this combined strategy has become a preferred method for many individuals aiming to maintain health. Calorie restriction, 5/2 intermittent fasting, time-restricted feeding, and the ketogenic diet are among the most popular dietary interventions today. Aerobic exercise, resistance training, and mixed exercise are the most widely practiced forms of physical activity. Exploring the best combinations of these approaches to determine which yields the most effective results is both meaningful and valuable. Despite this trend, a comparative analysis of the effects of different exercise and diet combinations is lacking. This study uses network meta-analysis to evaluate the impact of various combined interventions on body composition and to compare their efficacy.

METHODS

We systematically reviewed literature from database inception through May 2024, searching PubMed, Web of Science, Embase, and the Cochrane Library. The study was registered in PROSPERO under the title: "Effects of Exercise Combined with Different Dietary Interventions on Body Composition: A Systematic Review and Network Meta-Analysis" (identifier: CRD42024542184). Studies were meticulously selected based on specific inclusion and exclusion criteria (The included studies must be randomized controlled trials involving healthy adults aged 18 to 65 years. Articles were rigorously screened according to the specified inclusion and exclusion criteria.), and their risk of bias was assessed using the Cochrane risk of bias tool. Data were aggregated and analyzed using network meta-analysis, with intervention efficacy ranked by Surface Under the Cumulative Ranking (SUCRA) curves.

RESULTS

The network meta-analysis included 78 randomized controlled trials with 5219 participants, comparing the effects of four combined interventions: exercise with calorie restriction (CR+EX), exercise with time-restricted eating (TRF+EX), exercise with 5/2 intermittent fasting (5/2F+EX), and exercise with a ketogenic diet (KD+EX) on body composition. Intervention efficacy ranking was as follows: (1) Weight Reduction: CR+EX > KD+EX > TRF+EX > 5/2F+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 2.94 (-3.64, 9.52); 2.37 (-0.40, 5.15); 1.80 (-1.75, 5.34)). (2) BMI: CR+EX > KD+EX > 5/2F+EX > TRF+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 1.95 (-0.49, 4.39); 2.20 (1.08, 3.32); 1.23 (-0.26, 2.71)). (3) Body Fat Percentage: CR+EX > 5/2F+EX > TRF+EX > KD+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 2.66 (-1.56, 6.89); 2.84 (0.56, 5.13); 3.14 (0.52, 5.75).). (4) Lean Body Mass in Male: CR+EX > TRF+EX > KD+EX (Relative to CR+EX, the effect sizes of TRF+EX and KD+EX are -1.60 (-6.98, 3.78); -2.76 (-7.93, 2.40)). (5) Lean Body Mass in Female: TRF+EX > CR+EX > 5/2F+EX > KD+EX (Relative to TRF+EX, the effect sizes of CR+EX, 5/2F+EX and KD+EX are -0.52 (-2.58, 1.55); -1.83 (-4.71, 1.04); -2.46 (-5.69,0.76).).

CONCLUSION

Calorie restriction combined with exercise emerged as the most effective strategy for reducing weight and fat percentage while maintaining lean body mass. For women, combining exercise with time-restricted eating proved optimal for preserving muscle mass. While combining exercise with a ketogenic diet effectively reduces weight, it is comparatively less effective at decreasing fat percentage and preserving lean body mass. Hence, the ketogenic diet combined with exercise is considered suboptimal.

Adverse events profile associated with intermittent fasting in adults with overweight or obesity: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

There is little evidence to comprehensively summarize the adverse events (AEs) profile of intermittent fasting (IF) despite its widespread use in patients with overweight or obesity.

METHODS

We searched the main electronic databases and registry websites to identify eligible randomized controlled trials (RCTs) comparing IF versus control groups. A direct meta-analysis using a fixed-effect model was conducted to pool the risk differences regarding common AEs and dropouts. Study quality was assessed by using the Jadad scale. Pre-specified subgroup and sensitivity analyses were conducted to explore potential heterogeneity.

RESULTS

A total of 15 RCTs involving 1,365 adult individuals were included. Findings did not show a significant difference between IF and Control in risk rate of fatigue [0%, 95% confidence interval (CI), -1% to 2%; P = 0.61], headache [0%, 95%CI: -1% to 2%; P = 0.86] and dropout [1%, 95%CI: -2% to 4%; P = 0.51]. However, a numerically higher risk of dizziness was noted among the IF alone subgroup with non-early time restricted eating [3%, 95%CI: -0% to 6%; P = 0.08].

CONCLUSIONS

This meta-analysis suggested that IF was not associated with a greater risk of AEs in adult patients affected by overweight or obesity. Additional large-scale RCTs stratified by key confounders and designed to evaluate the long-term effects of various IF regimens are needed to ascertain these AEs profile.

Intermittent Fasting in Youth: A Scoping Review

Intermittent fasting (IF) focuses on the timing of eating rather than diet quality or energy intake, with evidence supporting its effects on weight loss and cardiometabolic outcomes in adults. However, there is limited evidence for its efficacy in adolescents and emerging adults. To address this, a scoping review examined IF regimens in individuals aged 10 to 25, focusing on methodology, intervention parameters, outcomes, adherence, feasibility, and efficacy. The review included 39 studies with 731 participants aged 15 to 25. Methodologies varied, with 18 studies on time-restricted eating and others requiring caloric restriction. Primary outcomes included cardiometabolic risk factors (11/29), body composition (9/29), anthropometric measurements (8/29), and feasibility (2/29). Most studies reported significant weight loss. This review underscores IF's potential in treating obesity in this age group but highlights the need for rigorous studies with standardized frameworks for feasibility to ensure comparability and determine IF's practicality in this age group.

Time-Restricted Eating and Bone Health: A Systematic Review with Meta-Analysis

Time-restricted eating (TRE) has emerged as a dietary strategy that restricts food consumption to a specific time window and is commonly applied to facilitate weight loss. The benefits of TRE on adipose tissue have been evidenced in human trials and animal models; however, its impact on bone tissue remains unclear. To systematically synthesize and examine the evidence on the impact of TRE on bone health (bone mineral content (BMC), bone mineral density (BMD), and bone turnover factors), PubMed, Scopus, Cochrane CENTRAL, and Web of Science databases were systematically explored from inception to 1 October 2023 searching for randomized controlled trials (RCTs) aimed at determining the effects of TRE on bone health in adults (≥18 years). The Cochrane Handbook and the PRISMA recommendations were followed. A total of seven RCTs involving 313 participants (19 to 68 years) were included, with an average length of 10.5 weeks (range: 4 to 24 weeks). Despite the significant weight loss reported in five out of seven studies when compared to the control, our meta-analysis showed no significant difference in BMD (g/cm2) between groups (MD = -0.009, 95% CI: -0.026 to 0.009, p = 0.328; I2 = 0%). BMC and bone turnover markers between TRE interventions and control conditions were not meta-analyzed because of scarcity of studies (less than five). Despite its short-term benefits on cardiometabolic health, TRE did not show detrimental effects on bone health outcomes compared to those in the control group. Nevertheless, caution should be taken when interpreting our results due to the scarcity of RCTs adequately powered to assess changes in bone outcomes.

Combined versus independent effects of exercise training and intermittent fasting on body composition and cardiometabolic health in adults: a systematic review and meta-analysis

INTRODUCTION AND AIM

Exercise training (Ex) and intermittent fasting (IF) are effective for improving body composition and cardiometabolic health overweight and obese adults, but whether combining Ex and IF induces additive or synergistic effects is less well established. We therefore, performed a systematic review and meta-analysis to compare the combined versus independent effects of Ex and IF on body composition and cardiometabolic health in adults.

METHOD

An electronic search was conducted in three main online databases including PubMed, Web of Science, and Scopus, from inception to March 9, 2023 for studies involving Ex plus IF trials versus standalone Ex and/or IF interventions in adults. Interventions had a duration of ≥ 2 weeks. Standardized (SMD) or weighted mean differences (WMD) and 95% confidence intervals were calculated in order to compare effects on body weight, body mass index (BMI), body fat lean body mass (LBM), visceral fat, and waist circumference. For cardiometabolic health, outcomes included fasting glucose, insulin, total cholesterol (TC), low-density lipoprotein cholesterol (LDL), triglycerides (TG), high-density lipoprotein cholesterol (HDL), systolic (SBP) and diastolic (DBP) blood pressure, and VO2max/peak.

RESULTS

Ex plus IF decreased body weight [WMD: -3.03 kg (95% CI: -3.44 to -2.61), p = 0.001], BMI [WMD: -1.12 kg.m2 (95% CI: -1.28 to -0.95), p = 0.001], body fat [SMD: -0.72 (95% CI: -1.23 to -0.21), p = 0.005], visceral fat [SMD: -0.34 (95% CI: -0.63 to -0.05), p = 0.01], and waist circumference [WMD: -2.63 cm (95% CI: -4.16 to -1.11), p = 0.001] more than Ex alone. However, changes in body composition and cardiometabolic health markers were not significantly different for Ex plus IF when compared with IF alone, with the exception of VO2max/peak [SMD: 0.55 (95% CI: 0.14 to 0.97), p = 0.009].

CONCLUSION

We demonstrate that a combination of Ex and IF produces superior changes in body composition, but not in markers of cardiometabolic health when compared with Ex or IF alone. Ex plus IF could therefore be effective for weight and fat loss but has no additive or synergistic effects for other cardiometabolic health markers.