The great Song Dynasty poet Su Dongpo, or Su Shi preferred to take long runs, and he thought that only by moving your body regularly could you have a strong body and adapt to the seasonal changes quickly.
In a letter to his friend Cheng Zhengfu, Su Dongpo talked about his exercising habit, which was to run five kilometers per day. He would slow down when he breathed hard, and sped up when his breath balanced. Su Dongpo would run until he was sweaty, hot, blood circulating and limbs feeling refreshed.
We can see that when Su was running, he stressed "qi", which means "energy" or "the essence of life". Su was a fan of qi gong, a system of deep breathing. He ran in the morning and sat in meditation at night, making qi flow inside his body. In a letter to his friend Zhang An'dao, Su said that after meditating for nearly 20 days, he felt his body was much stronger and could run from the first floor to the fifth without resting in the middle. He believed that by practicing this way, he could be immortal.