my personal story: more than 3 months ago, inspired by Jack Dorsey’s diet, I walked to my office (about 5-6km per day), and started one meal a day intermittent fasting. I didn’t lose too much weight (about 2-2.5kg max) but I gained lots of stamina and endurance. Now I’m a daily runner (~5km daily, 7-15km on the weekend) and nothing could prepare my body better than walking.