How to monitor training load?

Load control is the tool that lets you quantify the effort of a workout so you can compare it, add it up and monitor it over time. It answers the questions a coach asks every week: is this client piling up too much? Is the progression steady? Was last week's training similar to the training a month ago?

TrainerStudio takes the approach elite sport uses today: not one universal metric, but three complementary layers that together give a complete picture. This guide explains each layer on its own and how to read them together.

The three-layer framework

Diagram of the three layers: Layer 1 internal load (AU) to compare sessions, Layer 2 external metrics to program volume, and Layer 3 derived indicators (ACWR, monotony, strain) for risk, marked as coming soon — The three layers do not compete: they are read together. AU summarizes, external metrics make it concrete and derived indicators warn about risk.

Layer	What it measures	What it is for
1. Internal load (AU)	Overall perceived effort	Weekly trends, comparing sessions
2. External metrics	Specific physical work	Programming, adjusting specific volume
3. Derived indicators	Risk and variability	Deciding deloads, preventing injuries

No single number answers the question "how is this client doing?" on its own. The three layers are read together.

How this guide is organized

The guide has two parts. If you want to get it up and running, start with the practical part; if you want to understand why the numbers are what they are, go to the model part.

How to use load control (practice)

Configure an exercise — how to set the load mode, the CA coefficient and the discipline so the exercise counts.
Fill in the client's fitness profile — HRmax, FTP, critical velocity… the data cardio and endurance work need.
Read the load control page — the Charts and Tables views, the period controls, the totals and the warnings.
Break load down by groups — track metrics per muscle, discipline or goal.

How it works (the model)

Layer 1 · Internal load (AU) — the formula load = minutes × (intensity / 10)² × CA, why intensity is squared and how the minutes are calculated.
Layer 2 · External metrics — tonnage, minutes, distance and reps: the real numbers for programming volume.
Layer 3 · Derived indicators — ACWR, monotony and strain to decide on deloads (coming soon).
Intensity sources — how RPE, RIR, %1RM, %HRmax, %FTP and other references are normalized to a 0–10 scale.
The CA coefficient of each exercise — what CA is and which reference values to work with.
Calculator and how to interpret load — play with the formula, read canonical cases and learn to interpret the numbers and their limits.

If it is your first time, the quick route is: configure your exercises → (if there is cardio) fill in the client's profile → read the load page.

References

The model is grounded in the scientific literature on training load monitoring:

Foster, C. (2001). Monitoring training in athletes with reference to overtraining syndrome. Medicine & Science in Sports & Exercise.
Banister, E.W. (1991). Modeling elite athletic performance. In Physiological Testing of the High-Performance Athlete.
Gabbett, T.J. (2016). The training-injury prevention paradox: should athletes be training smarter and harder? British Journal of Sports Medicine.
Halson, S.L. (2014). Monitoring training load to understand fatigue in athletes. Sports Medicine.
Impellizzeri, F.M. et al. (2019). Internal and External Training Load: 15 Years On. International Journal of Sports Physiology and Performance.
Helms, E.R. et al. (2017). RPE and Velocity Relationships for the Back Squat, Bench Press, and Deadlift. Journal of Strength and Conditioning Research.