Estimating the Effect of Aerobic Exercise Training on Novel Lipid Biomarkers: A Systematic Review and Multivariate Meta-Analysis of Randomized Controlled Trials

The Effect of Exercise Training on Blood Lipids: A Systematic Review and Meta-analysis

BACKGROUND

Dyslipidemia is a primary risk factor for cardiovascular disease (CVD). Exercise training (EXTr) improves some lipid markers but not others; the literature is dated and analyses may be underpowered.

OBJECTIVES

To clarify which lipid markers are altered with ExTr and establish if information size had yet reached futility.

METHODS

We conducted a systematic review/meta-analysis, with meta-regression, to establish expected effect size in lipid profile with aerobic (AT), resistance (RT) and combined (CT = AT + RT) ExTr. We conducted trial sequence analysis (TSA) to control for type I and II error and establish if information size had reached futility.

RESULTS

We included 148 relevant randomized controlled trials (RCTs) of ExTr, with 227 intervention groups, total 8673 participants; exercise 5273, sedentary control 3400. Total cholesterol (TC) MD - 5.90 mg/dL (95% confidence interval (CI) - 8.14, - 3.65), high-density lipoprotein cholesterol (HDL) 2.11 (95% CI 1.43, 2.79), low-density lipoprotein cholesterol (LDL) - 7.22 (95% CI - 9.08, - 5.35), triglycerides - 8.01 (95% CI - 10.45, - 5.58) and very low-density lipoprotein cholesterol (VLDL) - 3.85 (95% CI - 5.49, - 2.22) all showed significant but modest 3.5-11.7%, improvements following ExTr. TSA indicated all analyses exceeded minimum information size to reach futility. CT was optimal for dyslipidemia management. Meta-regression showed every extra weekly aerobic session reduced TC - 7.68 mg/dL and for every extra week of training by - 0.5 mg/dL. Each minute of session time produced an additional 2.11 mg/dL HDL increase.

CONCLUSION

TSA analysis revealed sufficient data exist to confirm ExTr will improve all five lipid outcomes. CT is optimal for lipid management. The modest effect observed may moderate dyslipidemia medication for primary prevention. Prediction intervals suggest TC, HDL, LDL and TGD are only improved in one-quarter of studies.

Exercise intensity prescription in cardiovascular rehabilitation: bridging the gap between best evidence and clinical practice

Optimizing endurance exercise intensity prescription is crucial to maximize the clinical benefits and minimize complications for individuals at risk for or with cardiovascular disease (CVD). However, standardization remains incomplete due to variations in clinical guidelines. This review provides a practical and updated guide for health professionals on how to prescribe endurance exercise intensity for cardiovascular rehabilitation (CR) populations, addressing international guidelines, practical applicability across diverse clinical settings and resource availabilities. In the context of CR, cardiopulmonary exercise test (CPET) is considered the gold standard assessment, and prescription based on ventilatory thresholds (VTs) is the preferable methodology. In settings where this approach isn't accessible, which is frequently the case in low-resource environments, approximating VTs involves combining objective assessments-ideally, exercise tests without gas exchange analyses, but at least alternative functional tests like the 6-minute walk test-with subjective methods for adjusting prescriptions, such as Borg's ratings of perceived exertion and the Talk Test. Therefore, enhancing exercise intensity prescription and offering personalized physical activity guidance to patients at risk for or with CVD rely on aligning workouts with individual physiological changes. A tailored prescription promotes a consistent and impactful exercise routine for enhancing health outcomes, considering patient preferences and motivations. Consequently, the selection and implementation of the best possible approach should consider available resources, with an ongoing emphasis on strategies to improve the delivery quality of exercise training in the context of FITT-VP prescription model (frequency, intensity, time, type, volume, and progression).

Short-term HIIT impacts HDL function differently in lean, obese, and diabetic subjects

Introduction

High density lipoproteins (HDL) exert cardiovascular protection in part through their antioxidant capacity and cholesterol efflux function. Effects of exercise training on HDL function are yet to be well established, while impact on triacylglycerol (TG)-lowering has been often reported. We previously showed that a short-term high-intensity interval training (HIIT) program improves insulin sensitivity but does not inhibit inflammatory pathways in immune cells in insulin-resistant subjects. The purpose of this study is to evaluate HDL function along with changes of lipoproteins after the short-term HIIT program in lean, obese nondiabetic, and obese type 2 diabetic (T2DM) subjects.

Methods

All individuals underwent a supervised 15-day program of alternative HIIT for 40 minutes per day. VO2peak was determined before and after this training program. A pre-training fasting blood sample was collected, and the post-training fasting blood sample collection was performed 36 hours after the last exercise session.

Results

Blood lipid profile and HDL function were analyzed before and after the HIIT program. Along with improved blood lipid profiles in obese and T2DM subjects, the HIIT program affected circulating apolipoprotein amounts differently. The HIIT program increased HDL-cholesterol levels and improved the cholesterol efflux capacity only in lean subjects. Furthermore, the HIIT program improved the antioxidant capacity of HDL in all subjects. Data from multiple logistic regression analysis showed that changes in HDL antioxidant capacity were inversely associated with changes in atherogenic lipids and changes in HDL-TG content.

Discussion

We show that a short-term HIIT program improves aspects of HDL function depending on metabolic contexts, which correlates with improvements in blood lipid profile. Our results demonstrate that TG content in HDL particles may play a negative role in the anti-atherogenic function of HDL.

ApoB100 and Atherosclerosis: What's New in the 21st Century?

ApoB is the main protein of triglyceride-rich lipoproteins and is further divided into ApoB48 in the intestine and ApoB100 in the liver. Very low-density lipoprotein (VLDL) is produced by the liver, contains ApoB100, and is metabolized into its remnants, intermediate-density lipoprotein (IDL) and low-density lipoprotein (LDL). ApoB100 has been suggested to play a crucial role in the formation of the atherogenic plaque. Apart from being a biomarker of atherosclerosis, ApoB100 seems to be implicated in the inflammatory process of atherosclerosis per se. In this review, we will focus on the structure, the metabolism, and the function of ApoB100, as well as its role as a predictor biomarker of cardiovascular risk. Moreover, we will elaborate upon the molecular mechanisms regarding the pathophysiology of atherosclerosis, and we will discuss the disorders associated with the APOB gene mutations, and the potential role of various drugs as therapeutic targets.