When structuring your cardio and lifting, hold this thought in your brain: You can find videos of extremely buff NFL players doing multi-mile runs to boost their endurance and long-distance runners who lift to strengthen their running form and prevent injuries. The standard weekly guidelines for exercise, according to The Office of Disease Prevention and Health Promotion (ODPHP) Physical Activity Guidelines for Americans is 150 minutes of cardio and two days of muscle-strengthening activity (that targets all the major muscle groups) per week.