In the Milky Way, about 1 in 5 stars that are like our sun in size, color and age have planets that are roughly Earth's size and are in the habitable zone where life-crucial water can be liquid, according to intricate calculations based on four years of observations from NASA's now-crippled Kepler telescope.
Varying Incline. Varying the incline is another option for interval training using a good treadmill. Exercisers that want to vary the incline for interval training should still start with a warm up period, which should be a walk or slow jog at an incline of 1.0.
What is high intensity interval training? High intensity interval training (HIIT) is when you alternate between high and low intensity exercise(s) or between high intensity exercise and a short period of rest. For example, a short sprint up a flight of stairs followed by a walk back down is interval training.