Ya I just hit it for 30 minutes at a even pace, didn’t get the pump like u said but got the heart racing.. I think my abs do feel tight but then again I did a bunch of sit ups before going to the gymI don't feel anything but energy being expended. Like on my intervals, I can hit the same times for 500 meters for like 5 intervals, then afterwards because I'm tired, the times start to fall apart. You work 86% of your muscles, legs, core, back, arms. It's not like you get a pump or anything. Only time I felt anything was when I fukked up. My foot wasn't strapped in tight and that made my knee hurt a little bit, then one time my form was fukked up and instead of following through with the motion I was using my arms too much and pulling and I felt that, then one time in the heat of some intervals my form was fukked up during a rep or two and I could feel it in my back below my shoulder blade. In each of these situations I was cognizant and made the necessary adjustments in real time and continued on and the next day it wasnt an issue, no lingering pain or anything. It's not like bench press or pushups or squats where you do a bunch then the next day you're like "man I feel it" and decide whether you should rest or not. I do it before I workout 20-40 mins and I've done it after. The other stuff i do i should rest and take days off on, but not this.