Jumping

Jumping is movement in which a person or animal pushes off a surface and becomes briefly airborne. It relies on muscular force to overcome gravity and ends with a landing or another movement.

Ground reaction force: The force a surface exerts on a body in contact with it. During takeoff, the ground pushes upward against the jumper, accelerating the body into flight.
Skeletal muscle: Muscle tissue attached to the skeleton that contracts under voluntary control. Its contractions generate the forces used to push against the ground.
Vertical jump: A jump measured by the height reached above the takeoff position. It isolates upward jumping performance and is widely used in athletic testing.
Walking: A form of locomotion in which the body moves forward while at least one foot remains in contact with the ground. Walking lacks the airborne phase that distinguishes a jump.
Impulse: The change in momentum produced by a force acting over time. A jumper can increase takeoff momentum by applying force for longer.
Muscle contraction: The process by which muscle fibers generate tension, with or without changing length. Leg muscles create tension that extends the joints during takeoff.
Long jump: A track-and-field event in which athletes jump for distance from a takeoff board. It combines a running approach with takeoff, flight, and landing.
Running: A gait in which each step includes a period when both feet are off the ground. Running has an airborne phase, but alternates it with repeated foot contacts rather than one discrete jump.
Center of mass: The point representing the average position of an object's mass. Its trajectory describes the body's overall motion after takeoff.
Knee joint: The joint connecting the thigh and lower leg, formed chiefly by the femur, tibia, and patella. Knee extension contributes to the coordinated push-off.

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