(Age 40, male, 260 pounds, lifting diligently for just under a year)
For background, here is my post 23 days ago where I struggled to find a single tricep exercise that successfully targeted my tricep muscles. Thankfully I got good answers and played around at ridiculously light weights at high volume focusing on form and "flexing" my tricep during every rep especially during lockout to help my brain learn how to recruit tricep motor units. As a result, the most successful tricep exercise that "works" for me and isn't constrained by my limitations is assisted dips while keeping the body upright.
This makes me feel very fortunate because many fitness youtubers (Jeff Nippard and 2-3 others) argue that dips are arguably the best single tricep exercise followed closely by overhead cable tricep extensions, which I still struggle with but is a top priority that I'm focusing on for the next 3-4 weeks incorporating into my push day. The only other tricep exercise I feel I'm able to perform correctly and with acceptable form and good tricep targeting is the Close-Grip (slightly Incline) Bench Press however I struggle immensely with my elbows wanting to flare out and I have difficulty keeping them tucked in, especially my ~5% weaker left side elbow which brings me to my next question.
##Question #2
If I can't do more than 6-7 good reps in clean form (with about 4-6 more in shoddy form) of the Close-Grip bench press, does this mean I need to lower the weight until I can do 12 reps in good form? Or does it mean I need to stop when my form gets bad after the 7th rep and compensate by doing more volume by doing more sets? My goal is functional tricep strength and/or hypertrophy but I would slightly prefer strength by a tiny margin. (as an aside, ai says 30-45 degree elbow flare is fine apparently?)
Primary question (in title): What does it mean if I can perform 25% more reps on my 2nd working set of tricep exercises than my 1st working set of the same weight? And does it mean I'm failing my warmup sets or something else? My typical warmup routine is 5 minutes on treadmill at 3mph or 4.8kmh, 2 minutes of "elbow circles" (due to some men having proclivity for elbow pain when working triceps), and 1 warmup set of 40% - 50% weight of my working set for about 10 reps.
I fully agree with this! It seems that my body was converting my first working set into a warmup set so I should just embrace that rather than complain about it online. I will experiment around a little bit with it like you said and try lower weights but maybe my body needs a warmup set on my working weight? If so, I'll just do about half the reps of a normal working set and count it as a warmup set and see if that fixes my problem.
As a rookie, I don't think you need to be this meticulous... But if it helps you actually get to the gym and keep the routine to have a strict schedule/progress, sure!
I personally wouldn't do a warmup at my goal weight, neither for PR (because then you can't push it) nor for sets (because you get fewer sets if you loose one to warmup, and I like the numbers lol), but thats just how you want to count it.
Warning up is meant to lubricate your joints and capillaries and whatnot, to avoid injuries before going into heavy weights, so I wouldn't encourage warming up in heavy weights. Warm up the motion with multiple reps, not heavy resistance.
But if it works for you, it works for you. When you're elite enough you'll get a trainer and won't have to rely on internet randos anyway. Just avoid injuries and be kind to your body until then.
This is a context where what works for different people tends to vary a lot, so experiment with a few different strategies and find what you like best! As long as you're pushing yourself close to muscular failure for a couple sets, you probably will see an increase in strength regardless of the particular loading strategy.
Usually it's best for warmup sets to not be fatiguing at all - you want to save your energy for the heavy working sets close to failure that will provide the most stimulus. So I'd go for 6-8 reps at about half the weight you want to do in your first working set. Warmups are just to get comfortable with the movement and make any adjustments before you do your working sets.
You may like "wave loading" - progressively lowering the reps and increasing the weight over the course of your sets. All sets are performed within a rep or two of failure, but e.g. the first set is failure after 8-10 reps, second set is failure after 6-8 reps, third is failure after 4-6 reps, or something similar. You can use a 1RM calculator to estimate what difference in weight would bring you down from one rep range to another.
It may or may not also be helpful to bring yourself completely to failure in the first set to ensure you're stopping only when you cannot possibly do more reps, and not due to sensation of weakness, slowing of the movement, or moderate reduction in range. To do this, you'll want to keep doing reps until the cable absolutely will not move - you might have a few more reps in the tank on your first set than you realize. Raising the rep range a bit can also help with this.
(also, re: another question from the original post, you can do less than 6-7 reps of a movement and get stronger if you're getting close to muscular failure. I do a lot of sets in the 3-5 rep range, not all the time, but especially for big compound movements it can be great.)