...You don't necessarily have to run or train very hard. For health, the WHO recommends adults 150-300 minutes of moderate aerobic activity per week or 75-150 minutes of vigorous exercise, plus strength training at least twice a week. This type of physical activity reduces the risk of cardiovascular disease, diabetes, certain types of cancer, and premature death.

Therefore, for the average person, I wouldn't prioritize a specific type of exercise, but a combination: lots of walking or cycling plus two strength training sessions per week. It's quite effective, relatively safe, doesn't require a previous athletic background, and, most importantly, can be maintained for decades. It's consistency, not record-breaking weights or speed, that's most important for health and longevity.