LIVER FUNCTION AND LIPID METABOLISM MARKERS IN YOUNG ATHLETES FOLLOWING HIGH-PROTEIN DIETS
Abstract
Introduction: Metabolic syndrome (MetS) is an increasingly significant health issue among young adults, marked by the coexistence of visceral obesity, insulin resistance, dyslipidemia, and hypertension. A key component of its pathogenesis is chronic low-grade inflammation, reflected by elevated levels of biomarkers such as C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Recently, attention has turned to the potential of physical activity as a modifiable factor that can influence inflammatory status and reduce MetS risk.
Objective: This study aimed to review current scientific evidence on the impact of regular physical activity on selected inflammatory markers and the risk of MetS in young adults.
Methods: A systematic literature review was conducted covering publications from 2015 to 2024. Scientific databases including PubMed, Scopus, and ScienceDirect were searched using keywords such as "physical activity," "inflammatory markers," "cytokines," "CRP," "TNF-alpha," "IL-6," and "metabolic syndrome." Included studies were randomized controlled trials, systematic reviews, and prospective cohort studies involving individuals aged 18–35.
Results and conclusion: Findings revealed that regular physical activity- especially programs combining aerobic and resistance training- significantly lowered CRP, TNF-α, and IL-8 levels, while increasing anti-inflammatory cytokines. Participants with higher physical activity levels were consistently less likely to meet MetS diagnostic criteria, even after adjusting for BMI. Additional benefits included improved insulin sensitivity, reduced oxidative stress, and favorable changes in lipid profiles. The anti-inflammatory effects were dose-dependent, with the most significant outcomes observed in those performing at least 150 minutes of moderate-to-vigorous activity weekly. Physical activity should be regarded as a key preventive measure against MetS and long-term cardiovascular risk in young adults.
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