Just because "I have played football since ...." doesn't mean "I still play football".

Question

Answer

Hi Dennis, "I've played/done X since..." implies you still do the activity. If you have stopped you would say "I played" instead.

Answer

Do you mean "I played football since 2001"?

Answer

"I played football when I was young", or "I played football up until last year", or "I played from ... to... " (no longer play)
versus 
"I've played all my all life" "I've played football since 2001" (still play)

I can't think of a context in which I'd say "I played football since 2001" - that incomplete to me, like the rest of the sentence is missing - but if that sounds okay to you then it could be a regional thing?

Anyway, French is generally more strict than English, and of course, the point is that depuis is used with the present tense.

Answer

Hi Gruff, I understand and agree with what you say above, but there is an ambiguity in the statement "I have played football since 2001". 
Take the case of someone who last played football in 2002 - when he played only one single time. To the question: "Have you played football since 2001?" , he could truthfully say "[yes,]I have played football since 2001 [but just the once]". 
But... if you asked the question: "Have you been playing football since 2001" (which is what I think you are meaning), he would answer "No". 
To make the meaning absolutely clear, you have to use the progressive form - "have you been playing" (to denote an on-going action) and not the past (as you have done). 
I hope this clarifies the point I was making. :-)

Answer

Ah! Thanks for expanding on your point, Dennis. I completely understand what you meant now!

Yes, this is a complexity in the English where emphasis on the auxiliary 'have' can be used to assert something, emphasise a fact and can change the meaning. Of course, in speech this would be very clear, but it's harder to get across in text. The use of the progressive form is unambiguous as you say but, both might used in speech.

It hadn't occurred to me that the English might be read that way so this discussion hopefully clarifies that for everyone reading!

Thanks Dennis.