This is all about weight training, so you may want to skip it...
Last night was my first workout after taking a week off for work travel. I had been weight training since Dec without a break.
The new weights are 90% of the latest numbers from before. I did one warm-up set at 75% of the new weight followed by two sets of eight (2×8) for most of the exercises and 2×15 for squats. Everything was relatively easy, except for squats, supposedly they are supposed to be easy at the beginning of a cycle.
Over the weekend I read a blog post where the guy was wondering how many reps and sets he should do for maximum growth or strength. I didn’t have an answer for him, but it starting me thinking about the idea again. I’ve always been confused about the concept of a set beyond the meaning of a group of repetitions (reps).
If you do one set until failure (of form), that stimulates the muscles to become stronger and grow. In high intensity training for bodybuilding, that’s the plan. I can understand why you would want to do more sets: to squeeze more out of the muscles because they wear out "so easily", and can take more work, but why? If one set is all that is really needed to stimulate them, why more? Why 60s, 1min, 90s, 2min, etc. between sets? I know shorter times keep the heart rate up and less time for the muscles to recover, but is the intent to complete good sets to failure or to work on cardiovascular effort? More sets build endurance, but some trainers write that doing lots of sets, e.g., five+, means you’re not working that hard. If you’re dropping reps or changing weights in those, then that changes things.
The number of reps in a set also determines the total volume of work. I know that more weight with lower reps generally leads to more strength, but increase the risk of injury at the low end of one or 3-5 reps. Schemes use singles, 3-5, 6-8, 8-12, 12-20 reps, etc. depending on the body part and the goal. Is it really that much more beneficial to break the reps up with a short pause and do it again? I’ve been doing two sets, but there’s so much confusing information out there. Different trainers / writers mention different research where one set or two sets or three sets is best.
Then there’s the pump. The pump is bigger / stronger if you do more sets. The pump feels good though, so it brings satisfaction, experiential knowledge that you’ve done something. I’ve read that pumping up muscles is not directly related to stimulating growth. It’s just the working them to failure that counts.
The bottom line is what works for each person, but those (of us) with no experience would like something close to the "right answer" to start from to get a good start then just tweak things from there.