How to Keep a Training Log That Actually Helps
Introduction
Almost everyone who trains seriously has tried keeping a log at some point. Almost all of them abandoned it. And some of those who didn't have something worse: a log they fill in religiously and never read.
A log isn't a record of what you did. It's the tool that answers the only question that matters as you start a set: what do I have to beat today?
A log you don't read is a diary. One you read is an instrument.
Why it works
Worth knowing this isn't a quirk of tidy people: self-monitoring is one of the best-supported behaviour change techniques there is.
The meta-analysis by Harkin and colleagues, covering over a hundred studies, found that monitoring progress toward a goal significantly increases the likelihood of reaching it. And it found something more specific: the effect is larger when the record is physical — written — and when it's reviewed, not merely filled in.
That nuance is what separates a useful log from a decorative one.
There's also a practical reason: memory systematically inflates what you did. You remember the good days and forget the patchy weeks. A log is, above all, protection against your own narrative.
What to record
The bare minimum is four things per set:
Exercise · load · reps · reps in reserve.
With that you can already compare sessions. A real example of one line:
Squat — 70 kg × 8, 8, 7 (RIR 2, 2, 1)
That says everything needed: what you did, with how much, and how close to the limit. Next time you know exactly what to beat.
Plus two things per session:
A brief context note: "slept 5 h", "after two weeks off", "knee complaining on the way down". It's what will explain, three months later, why that week was bad.
A global effort number, 1 to 10, when you finish.
And nothing else. Every additional field reduces the chance you'll keep filling it in.
The error of recording too much
It's the number one cause of abandonment. A log with tempo, timed rests, detailed sensations and a photo of every set is a project, not a tool.
The practical test: if logging a session takes more than two minutes, you'll drop it. And a simple log kept for two years is worth infinitely more than an exhaustive one kept for six weeks.
The reverse applies too: writing only "did legs" allows no comparison, and therefore isn't a log.
Paper or app
It largely doesn't matter, and there are real differences worth knowing.
Paper is faster to fill, doesn't interrupt with notifications, and doesn't lead you to look at your phone between sets — a source of distraction and of rest periods that stretch on their own.
An app organizes the history, calculates volume and shows you the previous session without searching. For reviewing trends it's clearly better.
A good middle ground, if your phone distracts you: paper during the session, weekly transfer to a spreadsheet. It sounds cumbersome and it's five minutes that also serve as the review.
The part almost nobody does: reading it
Here's the difference between having data and using it.
Before every set: look at last session. It's the primary use and the highest-return one. Without it you're improvising the load.
Once a week, five minutes: how many sessions did I complete? Did anything go up versus last week?
Once every three months, half an hour: did I progress on my main lifts? What patterns show up in the notes? Which weeks were bad and why? This quarterly review is what informs plan changes, and it's the one almost nobody does.
Common mistakes
Logging only the good sessions. It biases the record in exactly the direction your memory already biases it.
Starting from scratch every time you change routines. You lose the historical comparison, which was the asset you were building.
Recording without RIR or any effort reference. "3×10 with 40 kg" doesn't say whether it was easy or barely achievable, and that difference changes everything.
Turning it into the goal. The log serves the training, not the other way round. If you're choosing exercises because they're easy to log, something has flipped.
Not recording injuries or niggles. It's the most valuable information when something recurs, and the least often written down.
Conclusion
A useful log has four data points per set, two per session, takes under two minutes to fill in and — this is the decisive part — gets read before every set and reviewed every three months.
Start at your next session with the simplest version: record exercise, load, reps and RIR. Nothing else. And before every set, look at what you did last time. That single habit makes training comparable, and without comparison there is no progression, however faithfully you show up.
References
- Harkin, B., et al. (2016). Does monitoring goal progress promote goal attainment? A meta-analysis of the experimental evidence. Psychological Bulletin, 142(2).
- Michie, S., et al. (2013). The behavior change technique taxonomy (v1) of 93 hierarchically clustered techniques. Annals of Behavioral Medicine, 46(1).
- Zourdos, M. C., et al. (2016). Novel resistance training-specific rating of perceived exertion scale measuring repetitions in reserve. Journal of Strength and Conditioning Research, 30(1).
- Burke, L. E., Wang, J., & Sevick, M. A. (2011). Self-monitoring in weight loss: A systematic review of the literature. Journal of the American Dietetic Association, 111(1).