How do you tie in hard work with relaxation?
The question seems to frame that hard work and relaxation are opposites. They are not.
Let's reframe the words to make better sense of this distinction.
Let's redefine hard work as full effort x time committed to a task.
And then let's redefine relaxation as efficiency.
Hard work means full effort, focus, and attention and time committed to a task. So if you're "working hard" you have 100% focus, effort, and attention on a task. Multiply that by the amount of time you spend on a task. That's how hard you're working.
Now relaxation, as I refer to it with mechanics, means that you are aligned with your skeleton in a way that doesn't require excess muscular tension. When your muscles are "relaxed", they can be reactive. When they can be reactive, you have more agility, you can react faster, and you have more options.
As you can see, they're not opposites. "Hard work" and "relaxation" can coexist. And it's best if they do.