Articles
Background on the concepts behind the calculators.
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Comparing 1RM Formulas: Which One Should You Use?
Epley, Brzycki, Lombardi, Wathan and O'Conner give different answers for the same set. The difference isn't an error – it follows from how each formula models the relationship between reps and load, and it grows quickly past five reps.
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How Often Should You Test Your Max?
A max is an appealing number because it is unambiguous. But progress comes from the sets performed below it – and that number can be estimated accurately enough without testing at all.
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5/3/1 or 8×3? The Program Is Decided by Progression, Not Sets
Two popular ways to structure a session look like they differ in sets and reps. The real difference is what decides when the load goes up – the calendar or your performance.
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How Much Does a Barbell Weigh?
An Olympic barbell weighs 20 kg, a women's bar 15 kg. But the rack holds plenty of bars that weigh neither — and because the bar is part of every calculation, an error there passes straight through to every percentage you train with.
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Plate Colours: What Red, Blue and Yellow Actually Mean
There is nothing arbitrary about weightlifting plate colours. They are an international standard designed so that the load on a bar can be read from across the room — and once you know the code, you never have to count a bar again.
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RPE and RIR: What They Mean and How to Use Them
RPE 8 means you could have done two more reps. That is the whole concept — but it leads to a way of adjusting load to the day that a fixed percentage program cannot do.
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Why the Percentage Chart Isn't Always Right
The chart says five reps is 87 % of your max. For some lifters it is 80 %, for others 92 %. That spread is not an error in the chart — it is what a chart is — and understanding it makes the chart more useful, not less.
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What Counts as a Good Bench Press?
A hundred kilos means something different at 60 kg bodyweight than at 100. The usual answer — "one and a half times bodyweight" — is a useful rule of thumb, but it is unfair to lighter lifters, and the reason is geometry.
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Prilepin's Chart Explained — and Its Limits
Prilepin's chart tells you how many reps belong at a given percentage. It is a useful yardstick, but it came out of weightlifting — and that explains both what it is good for and where it stops applying.
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Why the Calculated Weight Isn't Always Loadable
The calculator says 113 kg. The bar takes 112.5 or 115. The gap is small, but it recurs every session — and on the lightest lifts it is the single most common reason progress stops.
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Warm-Up Sets: How to Work Up to the Bar
A warm-up is not an opening ritual but part of the session's design. Too little and the first work set is wasted; too much and it is already fatigued — and both mistakes are avoidable with a few percentages.
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How Much Is Four Plates? Barbell Slang Explained
One plate, two plates, four 45s on each side — gym shorthand states loads as plate counts rather than weights. Here is the full conversion, in pounds and kilos, and where the numbers come from.
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