Your muscles are not going to squander away to absolutely nothing since you run half an hour per day.There are some systems by which aerobic exercise can interfere with muscle development or trigger actual muscle loss. Steady state aerobics leads to endurance adaptations such as increased mitochondria (aerobic energy factories) and aerobic enzymes in the muscle cells, while strength training can lead to hypertrophy, or development in muscle fibers. Note that aerobics in these studies has actually been shown to reduce the rate of muscle development, which is a far cry from causing muscle loss.
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Your muscles are not going to squander away to absolutely nothing since you run half an hour per day.There are some systems by which aerobic exercise can interfere with muscle development or cause actual muscle loss. The very first is that concurrent aerobic workout and strength training lead to completing adjustments in muscles. Steady state aerobics leads to endurance adaptations such as increased mitochondria (aerobic energy factories) and aerobic enzymes in the muscle cells, while strength training can lead to hypertrophy, or growth in muscle fibers. Note that aerobics in these studies has been shown to reduce the rate of muscle growth, which is a far cry from triggering muscle loss. I do not know if my body broke down muscle for fuel however later on it sure felt like my muscles had been broken down, or at least beat up.