I just started Total Body Training last week and I really like the program and the whole concept. I'm coming off a Lifting for Fat Loss program where I rested 2 to 3 minutes between sets. TBT prescribes 60 seconds between sets on 5 rep days, 90 secs on 8 rep days and 120 seconds on 15 rep days and that's what I did this last week. I know there are reasons for this (time under tension?) but was wondering if it would hurt my progress to add 30 to 90 secs when I feel I need it.
The reason I ask is because a couple of times my muscles have failed when I felt like I had moire juice. Lying on the bench press with the bar on my chest looking around for some help kind of sucked. Then on sitting military dumbell presses I couldn't even do the third set of 5 on Monday. I usually do 55 pound dumbbells (don't laugh) and completed 2 sets of 5. For the third set I couldn't even get them up after waiting 60 seconds. I went down to 50's and couldn't get one rep out of those either. Should I just stick with the program's rest intervals and get a spotter or is it OK to to wait a little longer on some sets?