Fix grammaticality of the sentence: When in a groups activities, everyone cooperates (teorically) and become easier such as non-stressing; Sure when it is a competitions the whole grup must working hard and achieve their goal, however if really is a competitions, it is normally to seen a members of the group taking apart credits by himself and thats why a group activity shouldn't been mixed together following any fact upon the team spirit.
In a group activity, everyone cooperates (theoretically) and it becomes easier and for example less stressful. Of course when it is a competition the whole group must work hard and achieve their goals, however if it really is a competition, it is normal to see a member of the group taking apart credits by himself and that's why a group activity shouldn't be mixed together with any fact besides the team spirit.