Most of the commitments that steal your rest were not imposed by force. They were invited. And you said yes. Not because you wanted to, but because in the moment, saying yes felt easier than saying no. The cost only became apparent later, when the calendar was full and the energy was gone.
The 10-10-10 rule is a simple filter that protects your rest before it is under threat. Before saying yes to any new commitment, ask three questions: How will I feel about this in 10 minutes? How will I feel about it in 10 weeks? How will I feel about it in 10 months?
In 10 minutes, the yes might feel generous. Helpful. Like the right thing to do. But in 10 weeks, it might feel like a drain you cannot escape. In 10 months, it might be the thing you point to and say that is where I lost my margin.
If the answer is exhausted in any of those three timeframes, the answer is no. Not maybe. Not I will figure it out. No. Because the version of you who said yes in the moment is not the version who has to live with the consequences for months.
The best boundary is a proactive one. One that prevents the overcommitment before it starts. Try the 10-10-10 rule on one decision today, even a small one, and notice how much clarity it provides. What commitment are you currently living with that would have failed the 10-10-10 test if you had applied it at the time?