It seems that except for black people, it doesn't mean anything that the soleus and gastrocnemius of other races are short. There are many people who jump high and many who don't jump high, which is quite strange. But the upper limit is basically short calf muscles. Moreover, the jumping ability of black people per capita is indeed better than that of the other two races. The thinness of black calves is genetically determined. The strong lower limbs of white and yellow people are also genetic reasons. Anyone who has played for a long time knows that on the wild court, the point guard with strong calves and strong figure is the most horrible. It is often a small steel gun that integrates speed, endurance and explosive confrontation. Anyway, I usually meet those weak and slender lower limbs on the court, and I basically think it's easier to fight. You don't know how hard it is for Howard to meet a center with strong lower limb strength and soft touch during the magic period. That kind of calf muscle is terrible in itself.
Leg bones are long, tendons naturally grow longer, and calf facets are mainly tendons. You see, they seem very thin, but it is a matter of proportion. Ordinary people standing next to them are not necessarily thicker than them. It is difficult to practice calf muscles. The part you are talking about is Achilles tendon, which is natural. People who are born short and strong are not thin, while people with slender Achilles tendon are just as explosive and resilient. That is a gift. This is the reason why Kobe Bryant's comeback after breaking his achilles tendon is not as good as before. People who exercise know that calves are stronger than thighs if they don't practice, because in calf life, if you exert more strength, you will run. Also, calves participate more! It's not quality, it's training volume, not a grade.
At their peak, James, Williamson and Buckley have stronger calves than most players in the same position in China, but their athletic ability is explosive, and they can jump much more than McGrady Durant Ingram, who is famous for his slender calves, and their sprint speed will not be slow. Therefore, there is no absolute correlation between calf thickness and running and jumping ability. The thick calf really affects the lateral movement, which can also be understood as the flexibility of the pace. Among the domestic players, there are countless players who have the ability to run and jump above the nba level, and there are almost no pace, especially the inside players. At the same time, the famous stars in the nba, including James and Williamson during and after the Heat, didn't traverse fast enough.