I ran five miles a couple times a week, went mountain biking about once a week, and periodically lifted weights.Like most Americans , much of my day was spent in front of a computer.I was 35 years old, 5’9″ tall, and 150 pounds, with a BMI of 22.2 and body fat composition of about 13 percent.
Post-hike, I weighed 140 pounds, with a BMI of 20.7. My body fat was 5 percent, according to a Tanita digital scale.
体重63.5kg（-4.5kg）
BMI値20.7（-1.5）
体脂肪率5％（-8％）
■休息時心拍数
( Though a very low heart rate may have its own health risks. ) After hiking for eight to ten hours a day for a month, my resting heart rate fell considerably, from 48 to 40 beats per minute.
My cortisol level was at the high end of the normal range before the trip and dropped by 40 percent during the hike—a testament to the stress-reducing benefits of being in nature , even when you’re pushing your body.
Before the trip, I was burning 66 percent fat and 34 percent carbs during low-intensity exercise or any activity during which I had a heart rate of 112 bpm. At a slow long-run pace, with a heart rate of 145 bpm, I was burning 52 percent fat and 48 percent carbohydrates. My crossover point—the heart rate at which I was burning carbs and fat equally—was 153 bpm, or a moderate-to-slow running pace.
After the trip, I was, as my test administrator at Real Rehab in Seattle put it, “a fat-burning machine.” At 110 bpm, I was burning 91 percent fat and 9 percent carbohydrates. At 145 bpm, I was burning 70 percent fat and 30 percent carbohydrates. My crossover point had moved to 168 bpm, which I reached at a fairly fast running pace. And even at my maximum heart rate (184 bpm), I was still getting a quarter of my energy from fat.
