Swimming is really good anytime. And 33 is good time to start, you are young, don't hesitate about it! Combine swimming with gym and right nutrition and the result can be very beautiful
Actually, I don't. And I don't recommend to invest if you do not have some good knowledge about specific ICO where you would like to put your money. 90% of all the ICOs is scam now.
Bitcoin is safe compared with the most of altcoins. I think you have to diversify your portfolio as much as you can. But it should be better to leave 30%-50% in BTC. Also, be very careful in choosing the coins to invest! And good luck!