Question

Which of the following is an example of proper movement for a biceps curl?

Answer 1

concentration curl where the elbow is braced against the inside of the knee
preacher curl where the elbows rest upon a sloped bench
prone-body incline curl performed lying prone on an inclined bench, where the force of gravity holds the upper arms in front of the trunk.
spider curl which uses the preacher bench but uses the other side, so curling is done at a 90 degree angle. This position is similar to the prone-body incline curl except that the preacher bench restricts the movement of the upper arm.