Cross-Train for Tolerance
Cross-training should be part of everyone’s marathon prep, but if you want to get the most out of your alternate activities, a few simple twists can turn them into biohacks.
Take the pool as an example. In a cold-water setting, preferably a cold outdoor pool, hold a light weight at your chest while swimming a lap underwater. Then tread water with the weight between your thighs. With repetition, this can help your body maximize oxygen use and improve lactic acid tolerance.
Another way to improve respiratory capacity and efficiency is by hiking while wearing a weighted vest. The vest creates resistance to diaphragm movement, strengthening the muscles around your lungs.