I exercise about every day, I started doing about 90 minutes straight on "steps" (I'm not sure what you call it) but it was at a smaller height. Now I am doing it on 10~+ inches, but due to my schedule it's harder to devote 90 minutes straight to it. Is it better to do this activity for 45 minutes twice a day, or will I find greater benefits if I just find the 90 minute block of time in which to exercise? I am not absolutely exhausted at 45 minutes, while I would be at 90. Thanks for any feedback.