Final answer:
Catching a ball by 'giving' with it and diving into water hands-first both extend the impact time, reducing the force and making them safer and more comfortable practices. Conversely, catching without giving and belly-flopping increase impact force due to the abrupt stop and larger surface area, making them less comfortable and potentially unsafe.
Step-by-step explanation:
When catching a ball, using a technique of "giving" with the ball and pulling your hands toward your body helps to reduce the impact force. This is because extending the time over which the ball slows down decreases the force experienced by your hands. Conversely, when you keep your hands still while catching, the ball comes to an abrupt stop, increasing the impact force, which can be jarring and potentially painful.
Similarly, when hitting water with your full palm, it mimics a belly flop. The large surface area coming into contact with the water all at once results in a greater force and a more jolting impact. This can be painful and is generally advised against. When you enter water with your hand diving in fingers first, you're imitating a proper diving technique—there is less surface area hitting the water at once, and the shape allows for a smoother entry, reducing the force of impact.
Therefore, in both cases of catching a ball and entering water, orientations that involve spreading the force over a larger area and longer time (such as with "giving" or diving hands-first) are recommended, while abrupt impacts with large surface areas (like keeping hands still when catching or belly flopping) should be avoided for comfort and safety reasons.