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Equation For Calculating Relative Strength


I have been trying to develop an equation to calculate an individuals relative strength. So far I have only factored in height and weight, and the reason is because someone that is 5'5 200 obviously has more overall muscle mass than someone at 6'5 200.

(Bodyweight + height in CM) / 1 rep max

The lower index is better.

6'1 180 benching 207 = 1.77
5'8 140 benching 130 = 2.23
5'5 152 benching 205 = 1.54
6'2 220 benching 230 = 1.77 (This is the flawed part of it)
5'9 195 benching 320 = 1.15
5'9 215 benching 405 = .96

Calculate your stats and post them. Use this to convert inches to CM if necessary:


I realize this is borderline stupid, but I thought it was interesting to see if there was a possible way to develop an accurate relative strength index.


What does height and weight have to do with relative strength? Or are you talking about pound for pound strength?


I always wondered that too. a shorter guy has a definate advantage over a taller guy if they are both the same weight


Interesting topic but I'm not sure I agree with your logic. By adding height and weight you are actually penalizing the taller lifter. A Better equation might be Height(inches)/Weight(lbs) * 1 rep max. The higher the better.

So if I am 6'2", 215 lbs and my 1 rep max bench is 350 lbs, I would be at:

74/215 * 350 = 120.47

Compared to a 5'8" 215 lb person benching 350 lbs.

68/215 * 350 = 110.70

The taller athlete benching more should rate higher.


Ah, I didn't even stop to think about that. Thanks for the input.

So with that equation, the new numbers would be:

6'1 180 benching 207 = 83.95
5'8 140 benching 130 = 63.14
5'5 152 benching 205 = 87.66
6'2 220 benching 230 = 77.36
5'9 195 benching 320 = 113.23
5'9 215 benching 405 = 129.98
6'0 195 benching 245 = 90.46

Now I'm wondering if there are any more variables that could be plugged into the equation.


Goofy, but interesting. Don't take this as knock, but how old are you?


If you ignore height, you can just use the wilk's coefficient.



As stupid as i think this is, ill throw my own two cents in.

Adding height and weight is silly or whatever you want to do with it. Your best best would be to make a coefficient based on BMI, which is weight/height^2

Then you multiply it by the lift, and hey, presto, you have a formula to live your life by.

Or you could simply measure the number of chinups and dips performed. Or the % of bodyweight of the weight for a 1RM weighted chin/dip.

The best thing to do of course is to just measure your penis. If you have a 10" monster its way more impressive to whip it out then it is to benchpress twice your bodyweight.


I am posting snipers on the roof. Next person to use the phrase "relative strength" or "functional strength" will become headless.

That is all.


I would do it this way.

weight/height will give you an average pound per unit height figure

then I would divide the weight lifted by the lb/inch figure

giving you some number, higher is better.

for example, my bw in pounds/my height in inches = 225/72=3.125

my best deadlift in pounds, 440 divided by the above figure gives a number = 140.8

a dude that pulls that at my height only weighing 175 has a figure of 181.02

so, take height in inches divided by weight in pounds and multiply it by your lift to get a number.


Hope that makes sense, I'm a little hung over.


Trying to measure strength per unit bodyweight is ridiculous. This is of course if we're defining strength as the ability to produce force and only muscle tissue produces applied force.

Since bench press is such a complex movement involving so many muscles and multiplanar movement especially in the shoulder girdle, trying to compare force production between lifters would be nearly impossible and the variables would be headache inducing.

Instead i'm going to create a formula comparing the lifters' ability to do work on the bar per pound of involved muscle. something like this:

(work done*)/(Mass involved muscle**)
*(Mass X Bar Travel Distance X 9.81)
**Pecs, Deltoids, Triceps, Lats=(LBM/5)
Here is a list of examples:

LBM - ROM - Weight Lifted - work/kg
50kg - 45cm - 100kg - 44.145J
50kg - 30cm - 150kg - 44.145J
60kg - 45cm - 120kg - 44.145J
60kg - 30cm - 180kg - 44.145J
70kg - 45cm - 140kg - 44.145J
70kg - 30cm - 210kg - 44.145J
80kg - 45cm - 160kg - 44.145J
80kg - 30cm - 240kg - 44.145J
90kg - 45cm - 180kg - 44.145J
90kg - 30cm - 270kg - 44.145J
100kg- 45cm - 200kg - 44.145J
100kg- 30cm - 300kg - 44.145J

This, of course, would be for a flat non-arched Bench Press.
An arch would offer different muscle activation, including more Lat. activation.
Also, using an arch has different magnnitude of benefit depending on the arm length of the lifter. Example:

Lifter 1) Flat bench ROM: 18"
Arched ROM: 18"-8"*= 10"
Mechanical Advantage(Arched/Flat):55.5%

Lifter 2) Flat bench ROM: 12"
Arched ROM: 12"-8"*= 4"
Mechanical Advantage(Arched/Flat):33%
*both lifters decrease ROM by 8"

Feel free to point out any flaws or errors.


Here's my equation:

(Height/Weight*1RM max + age-32)== You're still fucking skinny


That's a good one. My scientific calculator came up with:

(size of shirt less than a XXL) x (height/weight*1RM) - (the number of times you attracted attention last week because of the weight you lift) / (giving a damn about relative strength because you are still weaker than that really big guy at the gym) = pencil neck mutherfucker.

My numbers may be a tad skewed, however.


This reminds me of oone other formula...


Boris and Prof X,

I realized you guys are both damn right, and that this calculator is retarded. By the logic of the equation, a 5'11 135 stick benching 170 is stronger than someone 6'0 200 benching 245.

5'11 135 maxing at 170

6'0 200 maxing at 245

Not that benching 245 is good, but it's easy for anyone to bench under 200 because of beginner gains, so a skinny guy can look good even if he benches 170. I never intended to support the "I'm strong for my size!" BS. This calculator sucks, end of story. I was just fooling around with it for the humor/interest value, I guess.


In powerlifting years ago they had the Schwatrz formula. I think this was the most accurate of the different compraitive formulas in powerlifting.

Try to figure out more than that is dumb and should be met with the snipers as stated earler.

I'm 5'7" and about 210. My raw bench is about 150% bodyweight. It's been up and down over the years, but I'll take a 315 over a 230 , even though the 230 was a t 130.

The 42 year old Tom bencing over 300 will club the piss out of the 130 pound Tom at 18.

This is why they have weight classes in sports such as lifting and wrestling.

And this is why no one gives a shit about these sports compared to team sports like football. Fastest, strongest best football player wins as opposed to, well I'm pound for pound good.


A very good point in your last post DLboy.

You would have to factor in heavy squatter guy with a lot of lower body mass as opposed to doesn't squat guy with 30 less bodyweight pounds.


I actually thought the conversation was fairly well directed.

I have always been amused by those 5'6", 215lb. guys who bench 335 for a 10" stroke who mock the 6'2" 185lb guy who benches 225 over an 18" stroke.

Technically, the taller guy is actually stronger, but has less leverage, and/does more work.... or am I missing something?

I thought the relative bodyweight issue was related to being an indicator for other sports performance, such as acceleration, etc.

I guess the guys who got cut from the football/ basketball / soccer / etc. team need something to brag about...

Unfortunately, even though guys like Charles Poliquin were huge contributors at the beginning, T-Mag has never had a discussion forum for guys who lift weights to enhance other sports performance, and instead have only provided a forum for those guys who didn't make it in those sports, so they simply decided to make lifting the weights themselves a sport.... huh.

Interesting....but not so much.

So since being a great linemen is about balance, footwork, mass, and strength, maybe we can set up a forum for angry Riverdancers who have the footwork and balance part, but no strength or mass. That way they can have a place to let out their frustrations.

We could make it equal opportunity forum for all angry, athletes who .
never developed all aspect of athleticism.

Then have a Light in the Loafers vs. Extremely Heavy in the Loafers showdown!!!

Sweet.... (or not).

I bet the heated discussions between the twinkle toed dancers and the behemoth strongmen would really help advance athletic training as a whole....

Now, that all being said, I can honestly say that I really admire guys who lift the big weights. Personally I have narrow shoulders that have dislocated half a dozen times between the two, and have subluxed too many to count.... I have never pressed more than 365lbs myself. As a wide receiver of 190lbs, that wasn't too bad, especially since I ran in the 4.4s electronically in the 40, and have great springs....

You see in order for Performance Training to advance beyond lifting weights, those pencil neck geeks may have to take part in the discussion from time to time. I know that most of us rely on what we have witnessed in person (I do for sure, and I think many of the contributors do also). But, no matter if we use Supertraining for a 1 Board press or for a resource, the simple fact is that the westside template was derived from a set of periodization principles conceived by geeks in the trenches.... not PE coaches, or dumb assed ex-linemen who consistently blocked the wrong guy on 236 Power (but suddenly are geniuses of training), or by theoretical wanna be's who sat around on balance balls... but, conjugate and concurrent training was analyzed by geeks in the trenches on human guinea pigs.... thank you Russia. Take a few guys with natural ability in the sciences and analysis, and throw them in the trenches.... thank you so much.

So, while this conversation wasn't exactly advanced, it definitely headed in the wrong direction over the last few posts.

I will say up front that I will never squat over 600, or bench over 405.... I may never even get to these goals. But, I also know that many of the guys who are so bad-ass for benching alot will never know the joy of dunking a basketball, making a tumbling run finishing with a handspring and then a tuck, or basically move agily without looking like a mentally handicapped baboon with a broomstick crammed up its arse.... you know who you are.

It is conversations by people who are willing to look a little deeper that will eventually help strength dominant athletes to overcome these deficits on sporting endeavors that require ballistic power absorption / production and reactivity...

But, there is much work to be done. The hardest part is to overcome the very poor state of athletic training that exists today. Do you have any idea how hard it is to sell the idea of: you can actually retrain poor agility mechanics, build dynamic and reactive strength in new ranges of motion in situations involving high force, and actually increase speed!!!

I just spent the day with a DI soccer coach today who I have been working with on and off for a while.... well I have to overcome his 25 years of truth... the truth that S&C basically failed to improve performance for his athletes..... tough sell.

The bruiser in the bike shorts with a can of skoal permanently transfixed to every back pocket would like to explain to you how if you could just squat 900 pounds, you would be a better soccer player.... uh-huh.

Need to get stronger? Definitely. Being given an athlete specific solution to maximize rates and amplitudes of power absorption and production?

Yeah right.... fat chance... no pun intended.

Oops, you have some Skoal on your 4th chin.

So we have to overcome that, and the angry guys who stand up and say that guys who don't bench alot are pencil necked geeks.... frankly, I agree with them, but....

I will probably not be here on T-Mag for a while, because it is obvious that even though relative power production is the key indicator for speed, and that relative body strength is the key indicator for acceleration... both being enhanced greatly by trained reactive qualities, the forum is still about sticking out our chests and saying: who can bench the most....?

Sorry guys, I will have to sit this one out, I have to go to practice....

You win.... good job.



Jumanji, you sound a bit disenchanted with the whole S&C scene.
Whats really on your mind?


where your equation might have a flaw:

a) say you have a guy that is 5'10" 200 lbs with most of his muscle mass in his upper body...he had a big barrel chest...he also has very short arms relative to the rest of his frame...his 1 rep max in the bench is 365 lbs...and his bench stroke is 10"...

(177.8 + 200) / 365 = 1.035

b) another guy is 5'8" 205 lbs with most of this muscle mass in his lower body...he has a small rib cage...he also has very long arms relative to the rest of his frame...his 1 rep max in the bench is 350 lbs...and his bench stroke is 14"...

(172.7 + 205) / 350 = 1.079

your formula states that lifter A is a better bencher that lifter B even though lifter A pushes the weight four inches less that lifter B...

maybe your formula should take more factors into consideration that just height and weight to be accurate?