Everyone who trains for long enough ends up with a log. The people who progress fastest keep it from day one. Not because writing things down is magic, but because the next session’s decision (same weight, more reps, or more weight) needs the last session’s numbers, and memory is a poor place to keep them.

What to record

For every working set:

  • The exercise, by a name you will recognize in a year. “Row” is not enough; “Bent-Over Barbell Row” is.
  • The weight on the bar or the machine. For bodyweight moves, write the added weight or nothing.
  • The reps you completed with acceptable form. Half reps do not count.
  • The set type when it is not a normal working set: warm-up, drop set, to failure. This keeps your records honest, because a warm-up single should never become a “personal best”.

Once per session:

  • The date and the routine you followed.
  • A short note when something changed: a new gym, an injury, less sleep, a different bar. These notes explain the dips in your charts months later.

Optional, useful for experienced lifters:

  • RPE, how hard the set was on a 1 to 10 scale, or how many reps were left.
  • Rest time, if you are testing shorter or longer breaks.

What to skip

Bodyweight every day, calories per session, mood scores. They are not wrong, they just rarely change a decision about the next set. Keep the log short enough to fill in between sets, or it stops being filled in.

Paper or app

Paper works. A pocket notebook survived generations of lifters. Its weakness is the review: to see whether your squat moved in the last two months you have to page back and compute.

An app records the same things and does the arithmetic: the previous session next to the empty row, personal records highlighted, a chart per exercise, the total weight lifted per week. Trenno was built around exactly this loop: previous results at a tap, a rest timer that starts when you tick a set, records and charts on every exercise.

Either way, the rule is the same: write the set down before you rest, not after the workout.

The five-minute weekly review

Once a week, look at three things:

  1. Which lifts added weight or reps. Those are fine; keep the plan.
  2. Which lifts stalled for two weeks. Check the notes first (sleep, illness, form). If nothing explains it, drop the weight 10 percent and climb back over two weeks.
  3. Total sets per muscle group. If a muscle got zero sets this week, the plan has a hole.

That review is where the log pays for itself. Most people never do it because the data is scattered across pages; with a log that computes, it takes five minutes.

Records are motivation, if they are real

A personal record is the best set you have ever done at a weight or for reps. The log makes them visible, and seeing one turn green after a hard session is a real reason to come back. This only works if the log is honest: warm-ups marked, half reps not counted, no rounding up.

Start today, not with the perfect system

The best log is the one you keep. Open a notebook or an app, write down what you did today with the weights and reps, and repeat next time. The reviews, the charts and the records come from consistency, not from the format.