Cardio exercise

Cardio exercise works by stressing the cardiovascular and metabolic systems, triggering adaptive responses. When you engage in cardio, your stroke volume (the amount of blood pumped per beat) increases, eventually leading to a stronger, more efficient heart muscle. At the cellular level, it stimulates mitochondrial biogenesis, increasing the number and efficiency of 'powerhouses' in your cells. It also improves endothelial function by increasing nitric oxide production, which helps blood vessels dilate and reduces arterial stiffness. Additionally, cardio triggers the release of myokines—signaling molecules from skeletal muscle—that exert anti-inflammatory effects and improve glucose uptake (independent of insulin) through the activation of GLUT4 transporters.

Based on 2024-2025 guidelines from the American Heart Association (AHA) and World Health Organization (WHO):

• Weekly Volume: Aim for 150–300 minutes of moderate-intensity activity (e.g., brisk walking) OR 75–150 minutes of vigorous-intensity activity (e.g., running) per week.
• The 'Dose-Response' Benefit: Research suggests that exceeding these minimums—up to 300-600 minutes of moderate activity—can further reduce all-cause mortality by up to 31% (AMA, 2024).
• Incorporate HIIT: Include high-intensity interval training (4-minute bursts at 85-95% max heart rate) twice weekly; recent studies show this specifically improves hippocampal connectivity and cognitive function more effectively than steady-state alone (University of Queensland, 2024).
• Combine with Resistance: For optimal cardiovascular protection, split your time between cardio and strength training; this combination is proven to be more effective for metabolic health than either alone (European Heart Journal, 2024).
• Safety First: If you are habitually sedentary or have pre-existing conditions like severe aortic stenosis or uncontrolled arrhythmias, consult a physician before starting a vigorous routine.