How much exercise is safe: Expert advice on running, walking, and strength training

Optimal exercise balances benefits and risks. Running yields maximum advantages at 30-50 km weekly, while walking is effective up to 7,000-10,000 steps daily. Strength training is most beneficial at 2-3 sessions per week. Excessive exercise can lead to cardiovascular strain, injuries, and hormonal imbalances, highlighting the importance of moderation and recovery.