Calculating 1rm?

is this theory really work becuase I can put up 225 20 times and put up 285 5 times which there is a gap of about 30 pounds in calulated max

All the available formula and matrix are at best a way to estimate your likely 1RM, as previous members have said they are abit more accurate at 2-3 reps rather than 12+ reps.

The only way to find a close enough approximation is through trial & error and over time.

One note of caution ALWAYS underestimate your 1RM. If the table say you can do 400 I would choose 360 initially.

if you are referring ot the calculator commonly used to convert 1 rep max it gets less and less acurate the higher number of reps you do. 2-3 reps would be your best indication to convert. For example i did 275x3 on the calculator this came out to 300. The most i acutally put on the bar ever was 295 which i got up for 1 and failed at 300.

These calculators are approximations that fail when you start doing too many reps as a test. They dont take into account fiber type when calculating. If you are better at higher reps (slow twitch) then you wont be able to hit your theoretical max whereas if you are better at heavier weight (fast twicth) you’ll surpass your theoretical max.
I dont believe repping out at 225 is any accurate predictor of success in football. Once you pass 10 reps, then you are just wasting your time.

When you reach such high intensities, trying to calculate what you can lift by testing sub-maximally is difficult. For instance I can flat bench 225 for 28 reps, I can bench 315 for 18-20 reps, I get 405 for 6, I get 455 for 2. Once you get near the top of your capacity, its dramatic how much you drop your performance. you would think based on performance averages. I would get 405 for 8-10. Not so. When you are testing limit strength, the only way to be sure is to max. I know people worry about the danger, but is it really alot different than doing 2’s and 3’s.

Remember also that, with sprinters, there is a lot of muscle endurance involved, so the “pyramid” will have a very wide base compared to the top- compared to a weightlifter or thrower.

i use a formula that is pretty good from two to 8 reps. altho, as the reps get higher (closer to 8 and above) the room for error can greatly increase.

multiply the weight (ie 300lbs) x .03, multiply this by the number of reps. (ie 4), ; then add this to the initial weight. works pretty good.

300x.03= 9
9x 4 (#of reps)= 36

add this weight (36) to original to get max

336

just one way to do it

Here is a link that is very usefull in calculating your 1-rep max:

http://www.brianmac.demon.co.uk/maxload.htm

I have in my excel spreadsheet the first one. It works okay with me, but I do use common sense and the same exercises regularly

The second one would be easier to calculate in the head.