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Subacute Effects of Moderate-Intensity Aerobic Exercise in the Fasted State on Cell Metabolism and Signaling in
Layane Ramos Ayres1,2, Éverton Lopes Vogt3, Helena Trevisan Schroeder1
1Laboratório de Inflamação, Metabolismo e Exercício (LAPIMEX) e Laboratório de Fisiologia Celular, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre 90035-003, RS, Brazil.
Fasting exercise enhances metabolic health in sedentary animals by reducing plasma cholesterol and increasing nutrient storage capacity in brown adipose tissue. This suggests exercise in a fasted state may offer unique metabolic benefits.
Area of Science:
- Metabolic Physiology
- Exercise Biochemistry
Background:
- Physical inactivity leads to insulin resistance and metabolic dysfunction.
- Exercise benefits may be enhanced when performed during fasting.
- Single-bout exercise effects in fed vs. fasted states require further investigation.
Purpose of the Study:
- To compare the subacute effects of exercise in fed versus fasted states on metabolic parameters.
- To investigate the impact of fasted exercise on cellular signaling pathways.
- To assess biochemical changes following a single bout of exercise in different metabolic conditions.
Main Methods:
- Animal groups: fed rest (FER), fasting rest (FAR), fed exercise (FEE), fasting exercise (FAE).
- Exercise protocol: 30 min treadmill at 60% V˙O2max.
- Fasting duration: 8 hours pre-exercise; sample collection: 12 hours post-exercise.
Main Results:
- Soleus glycogen increased only in fasting groups.
- Triglyceride content rose in brown adipose tissue (BAT) and liver in the FAE group.
- Fasted exercise (FAE) reduced plasma total cholesterol compared to fasting rest (FAR).
Conclusions:
- Physical exercise during fasting demonstrates beneficial metabolic effects in sedentary animals.
- Fasted exercise led to reduced plasma cholesterol.
- Fasted exercise increased the capacity of BAT to metabolize and store triglycerides.
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