LOL! ^^^^
The reason for doing 21 minutes cardio is eliminating the boredom by splitting into 7's, so it is like do a 21-set but on cardio. It is as follows:
7 minutes: Incline 5.0, Speed 8.0 = Jogging
7 minutes: Incline 6.5, Speed 6.5 = Fast Walking
7 minutes: Incline 8.0, Speed 5.0 = Moderate Walking
You may have noticed but I make sure the Incline + Speed = 13.0 - I don't know why lol but I achieve what I am aiming for at all times by keeping my heart rate in and around the range of 120-140 BPM.
I am a bit weird though like that; numerically. Maybe it is because I am a future Chemistry teacher and I adore numbers? My idea of a Friday night in, after chowing down my post workout meal of course, is tackling some algebra! It is what is is!
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