It may also be that I am not any different except now I race. I am much more focused on how I feel. When I was more into long road rides and charity rides I didn't notice, but while I wasn't slow I was never really pushing myself super hard since it was an endurance based training. I also am now more an XC mountain biker which is constantly at aerobic/anaerobic threshold. Even just a fun ride is a fairly high intensity but it is the nature of the sport.