More exercise isn't always healthy: CMC Vellore doctor explains how much running, walking, strength training is safe

Physical activity is often hailed as a cornerstone of good health, with benefits ranging from improved heart function to enhanced mental well-being. However, recent guidance from experts warns that overdoing exercise may not always be beneficial and, in some cases, could even be harmful. Striking the right balance in how much and what type of exercise you do is crucial for long-term health outcomes.

Running: Find the Right Distance

Dr. Sudhir Kumar, MD, a senior neurologist trained at CMC Vellore and affiliated with Apollo Hospitals in Hyderabad, explains that running offers the most health gains when done in moderation. Running between 30 and 50 kilometers per week—or roughly three to five hours weekly—optimizes cardiovascular and overall health. Beyond 75 kilometers per week, the benefits plateau, and excessive mileage may increase risks such as atrial fibrillation, coronary calcification, and joint injuries.


Walking: More Steps, But Limited Extra Gain

Walking remains a safe and effective form of exercise for most people. Dr. Kumar notes that walking 7,000–10,000 steps per day, approximately 50–70 kilometers per week, delivers the maximum health benefit. Walking more than this does not substantially increase health gains, although it generally poses no harm.

🏃‍♂️🚶‍♀️🏋️‍♂️ How Much Exercise is Too Much?
Exercise is medicine 💊. But like medicine, dose matters.

📌 Running
▶️Max health benefits with ~30–50 km/week (or 3–5 hrs/week).
▶️Beyond ~75 km/week, benefits plateau.
▶️Ultra-high mileage may raise the risk of atrial fibrillation,…

— Dr Sudhir Kumar MD DM (@hyderabaddoctor) September 14, 2025

Strength Training: Focus on Quality, Not Quantity

Strength training is essential for maintaining muscle mass, bone strength, and metabolic health. Dr. Kumar recommends two to three sessions per week, targeting all major muscle groups. Increasing frequency to five or six sessions weekly provides minimal extra benefit and may elevate the risk of injuries, tendon strain, and hormonal imbalances if recovery periods are ignored.


Striking the Right Balance

The key takeaway from Dr. Kumar’s guidance is that moderate, consistent exercise tailored to one’s body and lifestyle is more beneficial than extreme regimens. A combination of cardiovascular activity, strength training, and sufficient recovery forms the optimal approach for long-term health, aligning with World Health Organization (WHO) and American College of Sports Medicine (ACSM) guidelines.