@prestonmcghee I'm 40. I've been working out consistently since I've been 15 and always pursuing different athletic goals and sports. It is 100% ingrained in my lifestyle.
Once I hit my mid 30s, my metabolism slowed down, it took me longer to recover, I tend to get more tendon and ligament injuries etc. I used to be able to work out hard, eat reasonably well but still splurge and look fantastic. Now I have to be much more measured and disciplined in how I train, what I eat, how I sleep etc.
Theres no replacement for youth (well, maybe trt but I haven't Crossed that bridge yet). I definitely found that, athletically, things have gotten harder the last 7ish years. I'm not as fast, or as strong, despite being more focused and careful with training diet and lifestyle.
If you're peaking athletically over 40 it means you weren't training in your 20s and 30s. That doesn't mean you can't enjoy an athletic life or make gains, and I think the older you get the more important that is, but, I can relate to feeling like things go downhill after a certain age.