Swimming-based training ameliorates cardiac dysfunction and oxidative stress in chronically stressed rats

Area of Science:

• Cardiovascular Physiology
• Stress Physiology
• Exercise Science

Background:

• Chronic stress is a significant risk factor for cardiovascular disease.
• Restraint stress in animal models can induce cardiac dysfunction and oxidative stress.
• Exercise, particularly swimming, is known to have cardioprotective effects.

Purpose of the Study:

• To investigate the impact of swimming training on cardiac structure and function in rats subjected to chronic restraint stress.
• To evaluate the effects of swimming on oxidative stress markers induced by chronic stress.

Main Methods:

• Forty young Wistar rats were divided into four groups: Control, Trained, Stressed, and Stressed and Trained.
• Training involved 60 minutes of swimming daily, five times a week for 12 weeks.
• Restraint stress was applied for 1 hour daily, five times a week, for 12 weeks.
• Assessments included physical capacity, blood pressure, echocardiography, histology, and oxidative stress markers.

Main Results:

• Swimming training improved physical capacity and partially prevented stress-induced increases in systolic blood pressure (SBP).
• Restraint stress impaired diastolic function (lower A wave, higher E/A ratio) and increased nuclear volume and oxidative stress markers (malondialdehyde, oxidized proteins).
• Swimming training prevented the stress-induced impairments in diastolic function and oxidative stress.

Conclusions:

• Chronic restraint stress negatively impacts cardiac function, increases blood pressure, and elevates oxidative stress in rats.
• Swimming training effectively counteracts these detrimental effects of stress on the cardiovascular system and oxidative balance.