Exercise, from a public health perspective, is an unmitigated failure. The world's longest-lived people live in environments that nudge them into more movement. They don't use power tools, they do their own yard work, they grow a garden.

The people you surround yourself with influence your behaviors, so choose friends who have healthy habits.

The longest-lived people eat a plant-based diet. They eat meat but only as a condiment or a celebration. Nothing they eat has a plastic wrapper.

So learning to play a new instrument, learning a new language - those sorts of things will pay dividends for years or decades to come.

Actually, when you get into your sixties and above, you want to think about exercise differently. It's not just about you know cardiovascular or lifting weights. It's also about avoiding accidents.

The beauty of moving naturally, i.e. walking and gardening, is they're low impact. You're less likely to fall down and break a hip. Setting up your life so you're nudged into general physical activity every day is a strategy for your entire life from age 10 to 100.

True happiness involves the pursuit of worth goals; without dreams, without risks, only a trivial semblance of living can be achieved.