Why short guys can dunk

We asked a kinesiology professor and a trainer who works with pro and college basketball players to explain why some shorter people can jump high enough to dunk. The answer? Genes and a lot of practice, which trains the brain to activate muscles in a precise sequence from shoulders to toes in an efficient kinetic chain.

Hands and arms swing forward and upward.

Head raises and trunk extends.

Core engages. Legs, core muscles, even feet need to be strong. If one muscle group is under- or overdeveloped, the body won’t accumulate as much force as it should.

Gluteus maximus contracts. The best dunkers have a high percentage of fast-twitch muscle fibers, which fire quickly, providing great power in short bursts.

Quadriceps contract. If you have shorter-than-average thighs for your height, you have the ideal mechanical setup for leaping, see below for details.

Calf muscles fires.

Small muscles in the feet give the final push. People who are very good at transferring forward momentum (running) to vertical momentum will dunk off one foot. Others need raw leg power to lift them, so they jump off two feet.

The dunk. The players don’t need to be able to palm the basketball; many players dunk two-handed or cradle the ball against a forearm.

How can I learn to dunk?

Trade out your genes to grow a few inches taller and acquire a higher percentage of fast-twitch muscle fibers. If that ship has sailed, you have two options left, according to kinesiology professor Tim Anderson and trainer Jacob Ross.

Get stronger. Ross recommends leg-strengthening exercises such as squats and single-leg squats, leg presses and calf extensions. Anderson suggests specifically strengthening the feet with toe raises and other barefoot exercises.

Practice jumping. Plyometric exercises — they often have “jump” or “hop” in the title — require explosive movements that teach muscles in the chain to work together. (Caution: They can also be hard on untrained joints and tendons.)

Shorter femur, better jumper

According to kinesiology professor Tim Anderson, it’s a lever issue: When you jump, your thigh acts as a lever that propels body weight upward. A shorter thigh resists movement less than a longer one. (Try a squat. Now imagine how much easier it would be with shorter thighs.)

SOURCE: Jacob Ross of EFT Sports Performance, who jumps off two feet to dunk; Tim Anderson of Fresno State, who tried to dunk when he was younger but blames deficient genes. GRAPHIC: Bonnie Berkowitz, Alberto Cuadra and Sisi Wei - The Washington Post. Published March 6, 2012.