What weight should I lift next? A simple progression rule

Choose a rule before the session

For this example, use three working sets of 8–12 reps on the bench press. Warm-up sets do not count towards the three. Choose a starting weight that lets you complete at least eight controlled reps on each working set, with a little room left rather than an all-out attempt. Keep your setup, range of motion and rest periods comparable between sessions.

Write the decision rule beside the exercise: “Add 2.5 kg total after 12, 12, 12; otherwise keep the load and build reps.” That makes the next session a small, specific task. A set of 12 followed by 10 and 8 is useful work, but it does not meet this particular rule for adding weight.

Worked example: from 50 kg to 52.5 kg

The load increase is 52.5 − 50 = 2.5 kg, or 2.5 ÷ 50 × 100 = 5%. Reps can fall after that increase; nine, eight and eight still sit inside the chosen range. These are example outcomes, not a promise that you will improve every visit.

When to add 2.5 kg, and when to add reps

Add reps when one or more sets remain below 12. Aim for one extra total rep if that is manageable; you do not need to add one to every set. Keep the same technique standard. Shortening the movement to force a larger number makes the comparison less useful.

Add 2.5 kg only after all three sets reach 12, and only if that increment suits the lift. At 100 kg, 2.5 kg is 2.5%; at 20 kg it is 12.5%. The same plate jump is a very different demand. Smaller plates may help with a lighter press. If the new load takes a set below eight, repeat or reduce the jump rather than pretending the rule has been met.

Round to plates you actually have

Barbell loads include the bar and both sides. With a 20 kg bar, 50 kg requires (50 − 20) ÷ 2 = 15 kg per side. For 52.5 kg, the calculation is (52.5 − 20) ÷ 2 = 16.25 kg per side. Adding one 1.25 kg plate to each side supplies the 2.5 kg total increase.

If your smallest plates are 2.5 kg each, your smallest balanced addition is 5 kg total. Do not write down 52.5 kg if you cannot assemble it. Keep building within the agreed range, find suitable smaller plates, or revise the progression rule before the next session. For dumbbells, record the weight of one dumbbell consistently: moving from 10 kg to 12 kg per hand is a 20% increase per hand.

A missed target is information

One weaker day does not establish a stall. Record what happened, including changed rest or equipment, and compare several similar sessions. Avoid changing reps, load and set count at once: you will struggle to tell which change helped.

If several comparable attempts stop moving, review the plan and consider a modest reset. For an illustrative 10% load reset, 60 × 0.90 = 54 kg; rounding down to a buildable 2.5 kg step gives 52.5 kg. Rebuild reps from there. That is an example policy, not a universal reset percentage. Our progressive overload guide explains what to record so this decision rests on your log.

How IronThane handles the next target

IronThane supports double progression, stall resets and plate-aware loads. Free next-move guidance carries the progression decision into your next workout, rather than leaving you to reconstruct it from old sets.

The Free tier includes logging, records and progress, deterministic plans, check-ins, next-move guidance, import/export including Strong CSV, and the default 80s theme. Cloud backup requires a configured, signed-in preview build. Coach Preview adds AI-assisted plan wording and coach chat. Coach-proposed plan changes need your review and Apply.

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