T Nation

The Bench RM Calculator Project

Hello. I’m thinking of making my own version of the RM calculator, and I’ll need your help. Basically, I’ll be using statistics to determine the “best” coefficients for reach RM% range. It definitely won’t be 100% accurate, but with your help, it could become more accurate than a lot of calculators you can find in the internet.

Here’s all you need to do. Determine the the MAXIMUM number of unassisted reps w/ good form you can do for the bench press using the ff. 1RM percentages: 90%, 85%, 80%, 75%, 70%, 65% and 60%. The format would look something like this:

90%: 3 reps
85%: 5 reps
80%: 7 reps
75%: 10 reps
70%: 13 reps
65%: 17 reps
60%: 22 reps

No need to give me your poundages. With enough data, I can make coefficients that are statistically accurate up to 20+ reps, so I’ll be needing a lot of your help. To make your data sound, determine everything in one workout that looks like this:

  1. Make sure you OPTIMALLY rested and nourished yourself.
  2. Obtain a safety rack and/or a spotter.
  3. Using multiple sets of singles, work up to your 1RM for the day.
  4. Rest 5-10 minutes after your 1RM set and do your 90% set to failure.
  5. Rest 5-10 minutes and do your 85% set to failure.
  6. Rest 5-10 minutes and do your 80% set to failure.
  7. Etc… until you finish your 60% set to failure.

Make sure you do everything in maximum controlled speed so you can maximize your reps. If anything, this workout is a great way to condition your bench press, so you really won’t be wasting your time doing this.

As soon as I have enough data, I’ll be releasing the coefficients to you guys. Thanks. :slight_smile:

90%: 2 reps
85%: 3 reps
80%: 5 reps
75%: 7 reps
70%: 9 reps
65%: 12 reps
60%: 16 reps

65% and 60% will be tested tomorrow. (EDIT: 12 and 16, respectively.)

These are based on my written logs.

Great idea, IMO. The workout you’re prescribing is pretty interesting in itself. I’ll post my results as soon as I do my bench workout next week.

Its not a bad idea, but it going to be hard to get the coefficients right. I’ll tell you right now after a true 1RM there is no way that tests at 90, 85,80 % are going to accruate. I have never hit 3 reps at 90% after a 1RM, but I can do if I go for that first. Never mind, testing 85% plus a few other in the same day. That is going to be totally inaccurate. You would need to test these things on different days to be more accurate. I think the test would be more accurate if you did something like this.

WEEK 1 1 RM
WEEK 2 75% RM
WEEK 3 90% RM
WEEK 4 65% RM

WEEK 5 1RM - cause you probably got stronger
WEEK 6 70% RM
WEEK 7 85% RM
WEEK 8 60% RM
Week 9 80% RM

This just an example to illustrate my point. It could be arranged differently.

[quote]Pemdas wrote:
I’ll tell you right now after a true 1RM there is no way that tests at 90, 85,80 % are going to accruate.
[/quote]

You’re right. It would be better to stagger the rep ranges. However, the 9-week thing you’re recommending may be too long to be accurate either. Hmm…

Day 1:
-Work up to max set of 1RM
-Rest 10 minutes
-Do max reps @ 75%

Day 3:
-Do max reps @ 90%
-Rest 10 minutes
-Do max reps @ 65%

Day 6:
-Work up to max set of (new?) 1RM
-Rest 10 minutes
-Do max reps @ 70%

Day 8:
-Do max reps @ 85%
-Rest 10 minutes
-Do max reps @ 60%

Day 10:
-Do max reps @ 80%

Oh nvm. I found something in my written logs.

90%: 3
85%: 5
80%: 12
75%: 15
70%: 20
65%: 23
60%: 28

But I think something’s wrong with my bench if my numbers are like that.

[quote]2274 wrote:
Pemdas wrote:
I’ll tell you right now after a true 1RM there is no way that tests at 90, 85,80 % are going to accruate.

You’re right. It would be better to stagger the rep ranges. However, the 9-week thing you’re recommending may be too long to be accurate either. Hmm…

Day 1:
-Work up to max set of 1RM
-Rest 10 minutes
-Do max reps @ 75%

Day 3:
-Do max reps @ 90%
-Rest 10 minutes
-Do max reps @ 65%

Day 6:
-Work up to max set of (new?) 1RM
-Rest 10 minutes
-Do max reps @ 70%

Day 8:
-Do max reps @ 85%
-Rest 10 minutes
-Do max reps @ 60%

Day 10:
-Do max reps @ 80%[/quote]

That much benching in that short of time would kill me.

I’ll be the douche to ask, whats the point? You either max and know your max or you don’t. its really that simple…

Instead of doing a statistical survey (those have been done many times before with probably much larger data) why not just see what YOU can do in different movements. It would serve much greater purpose for YOU. And even that might/will change over time.

What I’ve personally have found out is that something like

100% 1RM
95% 2RM
90% 3RM
85% 5RM
80% 8RM

seems to work pretty well at least if you take some margin of error. Also the dependence can be modelled by using a logarithmic functions…although there isn’t much point doing so from a practical point of view.

The table above seems to work pretty well for my bench, deadlift and lifts were you don’t lift your bodyweight (like you do in chins, dips or even squats). For squats the table works better if you take a portion of your bodyweight into the calculations.

For example: Assume bw is 75kg and max squat is 150kg.
Then 120kg would normally be 80% but if say 50kg of bw is taken into account then max would equal 200kg and 120kg squat would equal 170kg so that would be 85%.

This works at least for me and seems to explain why I always get less reps with say 80% (calculated without the bodymass) in squat compared to bench.

I wouldn’t ask your help if I’m doing this for myself alone. Me and my medical colleagues “slash” gym buddies are doing some research, and we decided to make this a part of it. We’ve already asked some people in some gyms to provide their reps, but the data’s not yet enough, which is why I’m here. I’ve also posted in other forums, and so have my colleagues.

[quote]undeadlift wrote:
Oh nvm. I found something in my written logs.

90%: 3
85%: 5
80%: 12
75%: 15
70%: 20
65%: 23
60%: 28

But I think something’s wrong with my bench if my numbers are like that.[/quote]

Actually, I’ve seen “abnormal” cases like that in some of the gyms here.

I’m with Synth here, a calculator is never as good a tool as ones common sense and gut…if you know your capabilities then you don’t need it, if you don’t know your capabilities then you shouldn’t be maxing.

[quote]Power GnP wrote:
I’m with Synth here, a calculator is never as good a tool as ones common sense and gut…if you know your capabilities then you don’t need it, if you don’t know your capabilities then you shouldn’t be maxing.[/quote]

Like I said, I’m doing this as part of research.

2274 i have a better idea in my opinion…

have one person max… a few days later max reps at 90%

have another max… few days later max reps at 85%

etc etc etc

this would be more effective. just have people volunteer for the % they would like to max rep in after testing one rep max!

Sounds good, but I still have to get ALL the maxes for the data to be more accurate.

Cool idea. I don’t know if you have seen this but it is a calculator that takes 2 maximal sets with different weights/reps and then calculates what you can do for reps 1-15. It isn’t absolutely perfect but pretty good. Renton (on here) did this after my article about calculating your 1RM. Hope you find it helpful.

http://renton.somee.com/default.aspx

Yeah i know. it would go like this

1 person maxes then next time they bench try at 90% me

Another maxes then does 85% max

then another maxes then 80%

i think it would be impossible for the data to be accurate if someone try all their rep maxes in one session. let alone two weeks. its very hard. i’ll do my best to help with your research though…

If we do it that way, there’s NO WAY to compare the various RMs of people who didn’t do the same RM. It shouldn’t matter how long it would take. Everybody should max at everything.

The problem is this. I know guys who can rep 225 more times than me, but I all out bench more weight. Its all in training. If I work on doing 225x20, it’ll look like I can make 400 enough though most guys who work for ONLY endurance will not bench 405 or anything close.

There’s a guy I talk to on another forum who trains for triathlons. He has squatted 225x20, x4. That’s insane volume. He cannot squat 300, I think he can do 275x1.

The problem is you’re assuming that math is ALL you need to consider when estimating a 1RM.

If this is research, are you ONLY considering the mathematical portion or are you actually asking people what thier style of training is, how many singles, doubles, triples, they do in training and how often they bench 80%, 85%, 90% and higher?

I think leaving this out makes the research incomplete. Its a LOT more work, but its much more complete. I’ll be honest. I’d disregard any research like this b/c there’s just not enough info other than the 1RM and how many times someone can do a certain weight below the 1RM. Also, how many people can honestly bench 95% of his max x2.

I max about every 5 weeks (I don’t care if people don’t like this). You can look @ my log if you care to get some data. I just believe its way too individual and based on genetics, conditioning, the routine, rest, diet, etc.

Like I said, this is just PART of the research. Trying to come up with coefficents regardless of background is just PART of a bigger scheme. I’d like to explain, but it’s rather complicated.