Lack of Practice... Going Backwards

I haven't been able to practise much lately, due to work and tiredness from jet lag. And of course, without practice, I can't improve. In fact, I have gone backwards. A standard pushing hands session was strenuous for me... I ended up with muscles aches on my legs, something that I haven't felt for some time (at least, not this bad...) Just a week without practice, and my legs are no longer as strong.

I guess this goes to show the importance of foundation skills in taiji (and probably all martial arts). As the saying goes, 练拳不练功，到老一场空。(Essentially, if you practise martial arts without practising foundation skills, you will still not get anything after years of practice when you grow old.) I guess it is back to basics again.