BPI Sports Whey HD is a blend of ultra-premium whey protein isolates and concentrates. Taken after a workout, it supports muscle growth and recovery, but it can also be used as a meal replacement by those trying to lose weight. Whey protein isolates are pure, fast-absorbing proteins that fuel and repair muscles quickly, maximizing lean muscle growth, increasing protein synthesis and speeding up the recovery process. Whey protein concentrates digest slowly, helping the recovery and muscle-building process continue long after your workout.