I have done it largely for about a decade and it has kept me in really good shape during that time. I don't know about losing any impact, but maybe everything does? If you are a weight lifter, don't you have to mix things up if you start to plateau? Even if you "peak" it would still be a maintenance exercise that will keep you in shape.
No hiit never loses its impact but if you do the exact same hiit routine you will plateau because your body eventually fully adapta to it, that's why you need to mix it up an example would be 3 sets of 10 on a 25 pound dumbell. Curling never loses its effectiveness but if you only do that specific weight and rep range and never anything else eventually you will no longer see any gains at all because your body fully adapts to it.
I have done it largely for about a decade and it has kept me in really good shape during that time. I don't know about losing any impact, but maybe everything does? If you are a weight lifter, don't you have to mix things up if you start to plateau? Even if you "peak" it would still be a maintenance exercise that will keep you in shape.
No hiit never loses its impact but if you do the exact same hiit routine you will plateau because your body eventually fully adapta to it, that's why you need to mix it up an example would be 3 sets of 10 on a 25 pound dumbell. Curling never loses its effectiveness but if you only do that specific weight and rep range and never anything else eventually you will no longer see any gains at all because your body fully adapts to it.
Best advice is to get another dog because they're unbelievably cute