"The whole lifestyle has changed," Koeman told the Return To Play football medical conference in London.
"One of the problems you see now in football is there is not enough communication on the pitch. That's all about social media. Everybody goes on it straight away on their phones."
The 53-year-old former Dutch international and member of Johan Cruyff's "Dream Team" at Barcelona, spoke of how things were different before the advent of smartphones, when team mates on long coach journeys interacted more with each other.
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"When I was playing, we played cards on the coach when we went to matches, we talked and we had communication," he added.
"Now everyone just puts on his headphones and is in his own world. For young players it is all about themselves and less about communication with the rest of the players.
"That is maybe one of the reasons they don't talk any more on the pitch. Communication on the pitch is so important even if it is just to help your team mates and say 'time' or 'turn'!
"That's so difficult now. To deal with this we do sessions in training, different exercises every week which are all about focus, communication and concentration."
(Reporting by Simon Jennings in Bengaluru; editing by Amlan Chakraborty)
