Do you want to perform in a competition? Or do you just want to be "healthy"?
Before you pick either one of these goals, you need to have a few things in place in order to succeed.
Sleep. You need to sleep as much as you can without getting fired or divorced.
Nutrition. You need to eat a nutrient dense diet, devoid of sugars or processed foods. Just eat real foods!
Stress levels. These need to be kept low. Take a few minutes each day to "tune out" and allow your brain to recover.
Now that we have all these big rocks in place, we can take on our training goals.
If you're training for health, you need to focus on the following: high intensity efforts with low volume, and very low intensity efforts with moderate volume.
What does this look like in real world terms?
Sprint and lift heavy weights 2-3 times per week. In the gym, focus on big compound lifts and look for heavier loads (as long as you can control them). When you're running, look for short, all out efforts, followed by lots or rest.
On top of this, spend some time moving at least 5 days a week, at a slow pace. Walking, hiking, playing on the floor with your kids. Spend 30-45min per day at least doing this.
Now if you're training for performance, you will need to focus on the specific demands of your sport.
Competing in long distance events (marathons, triathlons) will require a high volume of aerobic training. Your body needs to be taught to sustain an effort over long (sometimes very long) periods of time.
If you're competing in a strength sport (powerlifting, olympic weightlifting, strongman) your training will once again reflect the demands of the sport. In those cases, you will be doing lots of lifting with moderate to heavy weights. The stronger you want to be, the more training volume you will need to get through.
Now you might think that you can do both. You might think that running marathons is the best way to be healthy. Or that lifting weights 5 days per week is the way to live long and prosper.
But the reality is the following:
"Health stops where performance starts"
When you're pushing your body to high volumes of training, you will inevitably affect your health in a negative way. Whether it's by increasing long term risks of heart damage from distance running or increased chances of injury because of the demands imparted on the body by frequent, heavy lifting, there's no way around it.
Always remember that when you want push your body beyond health and longevity goals, there's a price to pay for it.
Leave your answer in the comments below!