I would say it is going to depend on how you are going to invest that amount. You can use that 10 bitcoin for a long term too.
By just simply holding it for a long time we can consider that already as a long term investment.
10 btc is really good amount to hold for the long term as this amount will allow you to make huge profits in future so saving it for the future is the best thing you can do with it.
Its may be the right time to buy the BTC cause the prices are low, after buying your BTC you can invest in other trade beside holding.....
So, in long term investment we can do trade beside than just holding BTC
Yes trading will allow us to grow our coins and we can also make good profits from it by taking the advantage of price fluctuations, hold will not make your coins grow like trading.