Long term, permanent burnout

My friend was telling me about a gymnastic article he read recently. The article was talking about young gymnasts who trained heavy at an early age (by that I mean maximal strength training and that kind of thing) versus gymnasts who did not do this type of training early on. Apparently the gymnasts who did maximal strength training blew away their competition at junior competitions and won many medals. However, they peaked really early at around 16 and then faded. Now the other gymnasts don’t do so well at juniour level but peak a lot later, do better at adult level competitions-making it to the olympics etc and are still able to compete at the highest level into their 30’s.

This got me thinking about other sports. There are soccer players who are at their best performing in their early 30’s while some go downhill after about 25. There are boxers who peak early and are past it by around 27, while others (especially heavyweights) are at their best well into their 30’s.

I know about short term burnout (If I train like a madman on monday and tuesday then I’ll be burned out by wednesday) and medium term burnout (if I take a 2-week break in July I feel fresh all year round but if I don’t take a break halfway through the year I will feel shattered and weak by October) but what about long term burnout? Short, term and medium term burnout is temporary. You rest up and you feel good again.

I’m not really 100% convinced that long term, permanent burnout exists despite the article my friend told me about, and examples of it in sport. What do you guys think? Do you believe it’s just age that slows a person down or do you believe that if you start early you will finish early? If so, what are the factors that will have an effect on the age you start to decline physically? Is it possible for a man to start training very early on in life but still keep improving into his 30’s? I’m just talking about general strength and conditioning, nothing specific. I’d love to hear what you think.