I've already whined in other threads about the loss of power and performance at age 74 with the decline starting almost four years ago. (I'm down nearly 25 percent in power since then.) In the Strava 70-74 class, I hate it when my PRs for that group get beaten and in most cases, I can't challenge to get it back. It especially galls me when my "speed" PRs of segments of one and one half minute duration are beaten by someone in my class by someone helped by two other riders riding with the new
PR setter. (I'm a solo rider.)
If one chooses to keep track of performance it can be beneficial sometimes healthwise. At a certain point in time, my sustained HR when doing a long hard effort suddenly dropped off about 10 plus BPM literally overnight. Over the next six months, I had various tests performed on my heart such as stress treadmill, thallium scan, and echocardiograms. All the docs said my heart was fine. I said no, it is not. Finally crossed paths with a cardiologist that knew something about cycling. He heard my complaint after meeting me the first time and said it was too bad I didn't know my wattage for the period in question. I did though and told him the before and after. He said without examing me, "Oh, you have a blockage, I guarantee it." A CT Angiogram showed a 70 percent blockage in my left main coronary artery. I got it stented in mid-2017 and the heart has purred ever since and never worked better, (adjusted for age-related decline.) Now, my heart LITERALLY "complains" as it is ahead of my muscles so I can't even use its maximum potential because my muscles can't produce enough sustained physical effort to tap into the upper exercise ability or limits of my heart.