"How much weight should I use?" on an exercise you have never done is not answered by a reference table: it is answered by a five-minute procedure that gives you today's load, and by two sessions to correct it. The rule that goes wrong least often: start with a weight you could lift at least five more times than the target reps, and add load only when the technique holds.
Why percentage-of-max tables do not help here
Percentages work if you know your max on that exercise. On a new one you do not, and estimating it from another movement is unreliable: the relationship between your squat and your Bulgarian split squat depends on mobility, balance and limb lengths, not only on strength.
Worse: in the first sessions of a new exercise the limit is almost never strength. It is movement control. Loading to the maximum your muscles can handle means training a flawed pattern under heavy load — the fastest way to cement a compensation.
The five-step procedure
It works for barbells, dumbbells, machines and cables.
- A set with no load or minimal load, 8-10 slow reps. This is about finding the path, not warming up. If you cannot find the position here, the problem is not the weight.
- First test load: something that feels clearly easy. On dumbbells, for someone training for a few months, often 5-8 kg for a pressing movement and 8-12 kg for a pulling one; on a machine, the first setting that offers noticeable resistance.
- Eight reps. Count how many you could still have done. If the answer is "more than six", go up one step and repeat.
- Stop when the estimate is 4-5 reps in reserve. That is your starting load for today's working sets: the logic of reps in reserve is in RPE and RIR.
- Do the planned sets with that load, even if it feels light. The first session on an exercise is for learning the movement under load, not for finding your limit.
The whole procedure costs five minutes, once. Doing the opposite — starting heavy and walking it back — costs a week of soreness and sometimes a niggle you carry for a month, as the guide to DOMS explains.
Where to start, by exercise family
Starting points, not prescriptions: they give you the first attempt, then the reps-in-reserve test decides.
| Family | Reasonable first attempt | Sign it is too much |
|---|---|---|
| Horizontal press (bench, weighted push-ups) | Empty bar or light dumbbells | Shoulders shrug toward the ears, wrists collapse |
| Vertical press (overhead press) | Empty bar | The back arches to help the drive |
| Horizontal pull (row) | A load that lets you pause a second at the top | The torso rises with every rep |
| Vertical pull (lat pulldown, assisted pull-ups) | Resistance allowing 8 clean reps | You yank yourself up, shoulders rise before elbows |
| Squat and variations | Empty bar or bodyweight | Heels lift, knees collapse inward |
| Hip hinge (Romanian deadlift, hip thrust) | A light load that forces you to feel the hamstrings | The back rounds, the movement becomes a knee bend |
| Single-leg (lunges, Bulgarian) | Bodyweight only, for at least two sessions | You lose balance or put the foot down to compensate |
For technical lifts the rule is stricter: in the first week of squatting or deadlifting you work on the movement, and the dedicated guides — squat and deadlift — are worth more than any extra plate.
Correcting it in two sessions
Session 1: you found the load with the procedure above. Write down the weight, the reps and how many you had left in the last set.
Session 2: look at that number.
| In session 1 you had left | In session 2 |
|---|---|
| 5 or more reps in reserve | Add 10-15% |
| 3-4 reps | Add 5%, or one rep per set |
| 1-2 reps | Keep the load, add a set if you want |
| 0, or you lost technique | Drop 10% and stay there for two sessions |
From there you are into normal progression, described in progressive overload: reps first, then load.
The mistakes that cost most
- Copying the person next to you. You do not know their training history or how many sets they have already done.
- Starting from the weight you used months ago. After a layoff the tolerable load is lower: the criteria are in the guide to returning after a break.
- Adding weight every session because "you must progress". On a new movement progression is weekly or fortnightly, not daily.
- Choosing the load by how tired it makes you. Fatigue does not measure stimulus: a badly executed set is exhausting and trains little.
- Changing the exercise before learning it. Without three or four sessions on the same movement you have no data to decide on.
The special case of machines
On machines the numbers are not comparable: the same "40" on two brands can mean very different resistance, because of cams and leverage ratios. Two practical consequences: do not carry the number between gyms, and always note the machine along with the load. It is also why progress on machines should be read in reps before weight.
FAQ
What weight should I start a new exercise with? With a load you could repeat at least four or five more times than the planned reps. The way to find it is one test set of eight: if you would still have had more than six reps in reserve, go up a step and repeat. The first session on an exercise is for learning the movement under load, not for discovering your max.
How much should I add, and how often? On a new exercise, add load only if you had three or more reps in reserve in the last set: 5-15% depending on the margin. Once you reach one or two reps in reserve, progression slows and goes through reps first, weight second. Adding weight out of habit every session is the most common way to stall within a month.
How do I know the weight is too heavy? Watch the technique, not the effort. The reliable signals are the same for everyone: the back changes shape during the set, the movement speeds up through the hard part to blast past it, a swing appears that was not there before, or the range of motion shortens. If any of those show up, that weight is training a compensation.
Can I use my squat percentages for other exercises? No, and it does not even work between similar lifts. The relationship between your loads depends on leverage, mobility, balance and familiarity: someone with a solid squat can be remarkably weak in a Bulgarian split squat for stability reasons, not strength. Percentages are useful once you know your max on that specific exercise.
Can I trust the numbers on machines? Only within the same machine. The plates are not comparable units across brands and models, because cams and leverage change the real resistance. Note the model along with the load and, when you change gym, run the test procedure again instead of carrying the number with you.
Where to start
On your next new exercise, spend five minutes on the test set and write the load together with the reps you had left. That second number is what tells you what to do next time. If you want it recorded without scraps of paper, Athleex keeps loads, reps and perceived effort per exercise, and shows them to your coach when someone is following you.