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.
Interval training combines short bursts of intense activity, called intervals, with periods of lower intensity, or rest periods. Switching between the two makes your body work harder, burning more calories faster than it would at a steady, moderate pace.