Sam Browne

Of my 15 years on Twitter/X, this has to be my favorite thread to date. Masses of wisdom in there. Great thanks to all who contributed 🙏 "When was I the most happy & healthy?" is a question that I don't think we reflect on enough. Common themes that stand out to me from the responses: * Living somewhere nice - lots of beaches, mountains etc. 🏔️ * Lots of free time/not being over-scheduled ⏳ * Sharing that time with family/friends 👨‍👩‍👧‍👧 * Lots of physical activity of different sources - strength/cross-fit, biking, hiking, running, swimming, climbing, skiing etc 🏋️‍♂️ 🚴🚶🏊🧗⛷️ * Being on a quest/working on something big (America's Cup, Elite Ironman, A new business) 🎆 * A simple lifestyle (living in a van, studio apt etc) 🛖 * Low pressure job (lifeguard, river guide, ski instructor)/remote job/working for yourself. 💻 Things that I don't see mentioned very much: * Crushing it at the office 🧑‍💼 * Making bank 💰💰 * Living in a mansion 🏡 etc. Food for thought.

"But isn't it sufficient to show the #HRV trends, just as long as my Whoop, Garmin, Apple is consistently inaccurate? I.e. if I'm always at 60 and I drop to 30, that's still meaningful, right?" No. Here's why... 👇 First you have to understand how these wearables are getting their data and how they handle errors in that data. In order to determine HRV, we need to sensitively measure the time between heart beats, i.e. the R-R interval (referring to the gap between successive R waves on an EKG). A heart rate strap gets these R-R intervals by directly sensing the electrical signals created by the heart that cause it to beat. Wearables, on the other hand, *infer* when the heart beat by measuring how light changes as blood flows through the skin with each pulse. This is called Photoplethysmography (PPG) Now, the problem with PPG is that all the sensor is capable of doing is assessing changes in light. These changes in light could come from the shadows created by a pulse of blood OR they could come from shadows in light created due to movement or changing light sources. There is no real way of determining which. So, to deal with this, PPG based units try to filter the incoming data & throw out values that seem unlikely. Let's play out an example of a (very) low HRV day. True RR Intervals (from HR strap) 1000ms - beat ✅ 1000ms - beat ✅ 1000ms - beat ✅ So, the heart is beating with no variability at all at 60 beats per minute (1000 milliseconds between beats) RR Intervals from PPG 1000ms -beat ✅ 200ms - obvious light "noise" ❌ 800ms - beat ✅ 1000ms - beat ✅ So, the PPG filter picks up the obvious light noise because it only occurred 200ms after the last beat and it's unlikely that the heart jumped up to 300bpm(!). No harm, no foul. But, what if through dumb luck, the interference is like this... 1000ms - beat ✅ 800ms - light noise ✅ 200ms - beat ❌ 1000ms - beat ✅ Now the noise is creating a problem because it's not so easy to determine what is noise and what is beat. In fact, the filter will probably get it wrong and throw out the 200ms gap, including variability that wasn't really there (as we know the 'true' intervals are 1000, 1000, 1000) So, really the HRV that you end up with on any given day is a combination of the "noise" itself and just dumb luck of where that noise occurred. Depending on the day, you could wind up with a filter that's throwing out good beats (because they occur too close to noisy beats) or misrepresenting bad beats as good. It's just one big crapshoot dependent on the patterns of noise in the sample. So, in short, no you can't assume that the inaccuracy in PPG methods will be 'consistently inconsistent' & therefore any 'trends' that you see in the data should be taken with a grain of salt.

Allometric scaling: The bigger you are, the more work you have to do to have a decent #VO2max I'm 6'5". Deal with it.

Solid advice from @Harry_Hardass this morning. He doesn't sugarcoat things 😊.... "Listen up, Alan. You're running on fumes, pal. Your body's screaming for a break, and that low HRV ain't lying. We're not going for any half-measures today – you're benching it. Rest and recovery aren't just fancy terms; they're your job now. Guzzle down some water, eat something that didn't come out of a wrapper, and maybe stretch a little or chill your mind if you can sit still long enough. And don't give me that 'but coach' face; rest is part of the program, not a detour. We're building you up for the long haul, not burning you out before it's game time. Shake off the guilt and park it. Your body's going to repay you tenfold when you’re back at it, full tilt. Clear? Now get out of my sight and take it easy. We've got work to do once you're not half-dead."