I mean, I did a 30 min cardio workout today. Did back earlier on and actually was roller blaring for about a mile even earlier in the day lol haven't roller bladed in years thought it'd be fun but it killed my feet. Anyway, I'll admit i was a little tired but I did 30min of 3.0 on 8 incline an I worked up a pretty good sweat, so I wouldn't say it does nothing, but i cN understand why 60 would be better