Not yet for physical health. But that saying kind of annoys me in a general sense given that the majority of technological advancement has specifically been to replace hard work we don't want to do. So there's good reason to believe a technological solution for physical health that doesn't require hard work will exist some time in the future.
And yet, everything seems to point to modern living not exactly being good for you. Not going outside gives Vitamin D deficiencies. Not sleeping properly means our brain is less sharp. Being constantly connected online means that I'm unable to do proper deep work. Being constantly able to see the "superb" lives lived by others means more self esteem issues.
It seems those among us (Mr. Money Mustache comes to mind) willing to live life the old-fashioned way: biking to work, mowing lawns manually, avoiding social media and eating home-cooked food are doing better than those of us early-adopting every technical solution under the sun.
Just because we want something is not a good reason to think that it's possible.
As I understand it, the health benefits of hard work are currently believed to be an integral part of that hard work. And, they're at least somewhat localized to whatever systems are doing the work.
Or from another perspective, weight machines and indoor air-conditioned treadmills are your technological solution.
They're the current technological solution, but they're essentially proxies to condense a naturally occurring process into a more efficient process; weight machines and treadmills provide an efficient method to work out whatever systems your exercise regime is designed to affect. But what you're after is the resulting byproduct of that exercise, not that exercise itself.
Similar to how biking uses the same inputs as walking, but makes it more efficient. So if your goal is to get somewhere as efficiently as possible rather than walking in and of itself being the goal, you're going to bike instead. Then comes along the car and you're no longer constrained to the natural capabilities of your body in order to travel, and it's a whole new ballgame.
Exercise has a lot of health benefits because it causes things in the body. From stretching things to tearing muscle fiber to causing your body to generate and release different hormones and steroids (and many, many other effects).
The technological solution the OP wants is something which simulates the effects of exercise on the body but without the exercise itself. Such as nanomachines that can be designed to stress test different components of the body and keep them active or that cause the same types of micro-tears in muscular tissue that weight lifting does. As we learn more about the body, and we make smaller and smaller machines that are capable of operating from within the body, we can leverage those machines and that knowledge to directly maintain an ideal state of fitness regardless of externalities such as an individuals predilection or capacity for the level of working out needed to maintain that ideal state.
Not yet for physical health. But that saying kind of annoys me in a general sense given that the majority of technological advancement has specifically been to replace hard work we don't want to do. So there's good reason to believe a technological solution for physical health that doesn't require hard work will exist some time in the future.