With a higher at , you will be able to sustain faster marathon and ultramarathon paces 若有较高的氧债门槛，你能维持较快的马拉松和超马的配速。
2.
Now 42 and running a natural foods company in san francisco , karnazes has just written a book called “ ultramarathon man : confessions of an all - night runner ” 现年四十二岁而且在旧金山经营天然食品公司的卡奈兹才刚写了一本书，书名为超级马拉松侠：一名通宵跑者的告白。
