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Published on: April 28, 2023
Physiological adaptations during endurance training below anaerobic threshold in rats
Gustavo Gomes de Araujo1, Marcelo Papoti, Maria Andréia Delbin
1Laboratory of Sports Applied Physiology, School of Applied Sciences, Campinas State University, Pedro Zaccaria, 1300, Santa Luiza, Limeira, SP, 13484-350, Brazil.
Continuous swimming exercise at 80% and 90% of lactate minimum (LM) significantly improved aerobic performance in rats. While glycogen stores increased, key biomarkers and antioxidant enzymes remained largely unchanged, indicating a notable aerobic impact without major physiological stress.
Area of Science:
- Exercise Physiology
- Biochemistry
- Sports Science
Background:
- Understanding the physiological adaptations to high-intensity exercise is crucial for optimizing training protocols.
- The lactate minimum test (LM) is a valuable tool for determining exercise intensity.
- Assessing biomarkers and performance metrics provides insight into the body's response to training.
Purpose of the Study:
- To evaluate the effects of 12-week continuous swimming training at 80% and 90% of LM on rats.
- To analyze changes in antioxidant activity, hormone levels, biochemical markers, and performance.
- To examine alterations in muscle glycogen stores following high-intensity exercise.
Main Methods:
- 100 rats were divided into control, 80% LM, and 90% LM groups.
- Training involved 60-minute swimming sessions, 6 days/week for 12 weeks.
- Measurements included aerobic/anaerobic performance, glycogen concentration, creatine kinase, and corticosterone levels.
Main Results:
- Aerobic performance increased by 43% (EG80) and 34% (EG90) compared to baseline.
- Gastrocnemius glycogen increased in both training groups; soleus glycogen increased in the 90% LM group.
- Creatine kinase and corticosterone levels showed some increases, while antioxidant enzymes remained unchanged.
Conclusions:
- Continuous exercise at 80% and 90% of LM significantly enhances aerobic endurance in rats.
- These training intensities lead to increased glycogen storage without substantial negative impacts on antioxidant enzymes.
- The study highlights a marked aerobic benefit of high-intensity training with minimal significant biomarker alterations compared to controls.
