Please help me to make some more valuable support sentences

On the one hand, there are many reasons why people choose individual sports . Firstly, sportman may pay more attention to practicing. They coudn't be distracted by chatting with others or eating too much. Secondly, players would easily change sporting interests to their preference. They stand the chance to try and pick up sport which is suitable to them. For example, not only they could play football but they also go skiing at another occasion.