Load selection guide
How to choose the right weight for an exercise
Pick a safe, useful starting load, calibrate it with reps in reserve, and make small changes without testing failure on every exercise.
The short answer
Choose a weight that lets you complete the target repetitions with stable technique and the intended reps in reserve. If you are new to the movement, begin conservatively, use the first work set as calibration, and increase only enough to move into the target effort range.
Start from your last real set
Replace guessed loads with an informed default.
LogFast remembers what you actually completed and how hard it felt, then gives you a starting load you can correct instead of recreate.
Build your exercise historyStart with the job of the set
A set of five for strength practice and a set of twelve for muscle growth do not require the same load. Decide the rep target, technique standard, and effort range before choosing weight.
For an unfamiliar exercise, the first session is calibration. A lighter set teaches more than a guessed number that immediately breaks technique.
Use reps in reserve as the adjustment dial
If the target is eight reps with two or three reps in reserve and you finish knowing you could do six more, add a modest amount. If the eighth rep is a grind or form changes, reduce the load.
RIR is an estimate, and people improve at it through practice. Record the result, then compare the same movement across several exposures.
Make the smallest useful jump
ACSM progression guidance suggests increasing load by roughly two to ten percent when you can exceed the target repetitions by one or two. The lower end fits smaller lifts and trained lifters; larger jumps may suit big movements or very light starting loads.
Load is not the only progression. Another repetition, cleaner range, better control, or the same work at lower effort can all be meaningful.
Machines and dumbbells need setup notes
Machine stacks can differ between models, and dumbbell labels may be per hand. Record units, seat position, handle, stance, and machine identity when those details affect the movement.
When equipment changes, treat it as a new baseline instead of forcing the old number to match.
Frequently asked questions
What weight should a beginner start with?
A load light enough to complete the target reps with stable technique and several reps left. Increase gradually after a successful calibration set.
When should I increase weight?
When you consistently reach or exceed the rep target at the intended effort and technique remains stable.
Should every set go to failure?
No. Many programs intentionally keep repetitions in reserve to preserve technique, manage fatigue, and repeat quality work.