Dr. Robert Whitfield explains that HRV, tracked by your ring, measures how well your body adapts to stress, not fitness. Higher HRV means more physiological reserve before surgery. Sleep, alcohol, hydration, and diet shift it, but only the monthly trend matters, not daily readings.
Hey, if you wear one of these, there's a number on it that tells you if your body can handle surgery. It's your heart rate variability, HRV, and it's not what most people assume it is. It's got nothing to do with how fit you are. Your heart doesn't beat like a metronome. The gap between one beat and the next changes slightly every time. HRV is measuring how much it changes. When that number is high, your body's handling stress well. It can react, it can adapt. When it's low, you've got way less room to move, and surgery is the biggest stress event for your body. That's the whole reason doctors check whether or not someone's heart has the physical ability to react to that experience, or if they've already already maxed out before they're even on the operating room table. The good news is it can change. What you eat, the water you drink, the air you're breathing, and how you sleep. Small changes to any of those and your HRV will get stronger. Now, I want to be careful here. This isn't a diagnosis and it cannot predict your recovery. Anyone telling you that is trying to sell you something. One bad night's sleep tanks it. A glass of wine tanks it. So today's number tells you almost nothing on its own. What's worth looking at is the monthly average. If yours has been sliding for 4 weeks and you don't know why, that's information you need to take to your doctor.
