There are several situations in which one falls forwards. The more common situation is tripping on something and falling forward. Another situation is falling forward into a swimming pool or falling from a swimming pool jumping board. Yet another situation is falling over a railing, off a ledge, or falling overboard. And of course there is falling forwards intentionally in acrobatics, gymnastics, martial arts and in kung fu movies.
In Olympics swimming, there is one jump from the diving board where the swimmer goes into a fetal position in mid air and then straightens the body out to enter the water. When one falls from a height of 20 to 30 feet, one has time to go into a fetal position and then hit the ground either with the front of the feet or the shoulders and upper back, and immediately roll forward with the body in a tight fetal position again. If one lands on the shoulders and upper back, one needs to hold the head and neck very lose to the chest with the forearms clamping the head to protect it.
In kung fu movies when the actor, actress or stunt double jumps forward from a ledge or wall or beam, the person makes a summersault in mid air and lands on the feet with sword drawn.
When one trips on a dry floor and falls forward, instinct will move the hands and arms forward to break a fall so the face will not hit the ground or the floor. While falling forward, the hands and arms are held in front of the chest or slightly higher out of instinct to protect the face. The arms are not outstretched completely but are slightly bent. This bend at the elbow serves as a cushion upon impact when the palms hit the floor. Cats land on the ground with their hind legs bent to cushion the impact.
If one trips on a wet floor and falls forward, there are two ways to hit the floor. The first way is the same as hitting a dry floor. The hands and arms slightly bent in front of the chest will hit the ground first and protect the body from impact. The other way is to consciously twist the body sideways in the fall and land on the shoulder and upper arm, and make sure the head does not hit the ground. One can use the forearm to protect the face when the shoulder and upper arm hit the ground. Those who have martial arts training are taught to fall on the side of the body when one falls forward.
Conscious or intentional turning of the body to land on the side of the body when one falls forward can also be seen with the good soccer players. I observed this in the recent games played by AC Milan and Barcelona.