If you want the best running shape for HYROX, aim for half marathon shape. Here is the science. HYROX lasts between fifty and ninety minutes for most athletes. That time domain matches the physiological demands of a strong half marathon better than any other race distance. Five kilometer training builds speed but not enough durability for eight runs. Marathon training builds durability but usually costs you strength and power. Half marathon training sits exactly in the middle and matches the intensity of HYROX almost perfectly. A half marathon is run near lactate threshold which is the intensity where your body produces and clears lactate at almost the same rate. HYROX is raced in this same zone. When you improve threshold through half marathon style training, every run between stations becomes easier and your heart rate recovers faster when you return to a sled, carry, or machine. Typical half marathon training also lives in the sweet spot for HYROX volume. Twenty five to forty mi...