Collaborative Overload

time spent by managers and employees in collaborative activities has ballooned by 50% or more...How much time do people spend in meetings, on the phone, and responding to e-mails? At many companies ... 80%, leaving employees little time for all the critical work they must complete on their own...
In most cases, 20% to 35% of value-added collaborations come from only 3% to 5% of employees... known for being both capable and willing to help, they are drawn into projects and roles of growing importance...a single “extra miler”... can drive team performance more than all the other members combined... Soon helpful employees become institutional bottlenecks... so overtaxed that they’re no longer personally effective... the work they do to benefit others goes unnoticed...
What can leaders do to manage these demands more effectively?