Training load tracker

What is training load?

Training load is the total stress of your training: how long you go multiplied by how hard it feels. It is the simplest honest way to compare a long easy ride, a brutal gym session and a five a side game on one scale.

This tracker uses the session RPE method, developed by Carl Foster's research group in the 1990s and used across professional sport since. Every session scores duration in minutes times effort from 1 to 10. A 60 minute steady run at effort 5 is 300 arbitrary units, AU. A 30 minute all out interval session at effort 9 is 270 AU. Different sessions, similar cost, which is exactly the point.

The magic is not in any single number. It is in the pattern. Bodies, and tendons in particular, tend to cope well with the loads they are used to and notice sudden changes in the loads they are not.

How this training load calculator works

The tracker compares two windows of your training. Your acute load is the last 7 days. Your chronic load is your average week across the 21 days before that, which is your recent normal, the amount of training your body currently expects.

Dividing one by the other gives your load balance. Around 1.0 means this week looks like your recent normal. Well above it means you are doing noticeably more than you are used to. Well below it, and your base is quietly shrinking.

Honesty matters here, so here it is: the research on these ratios is genuinely contested. A ratio cannot predict injury, and anyone claiming theirs can is selling something. What the evidence does support more consistently is the broad principle: big, sudden changes on a small training base are worth respecting, and a well built chronic load is protective. That is why the headline number here is your week on week change, with the ratio kept as a secondary planning guide.

Why runners and jumpers get extra attention

Running, jumping and sprinting store and release energy through tendons on every stride. Tendons adapt to that brilliantly, but slowly, on a timescale of weeks rather than days. What they notice most is sudden change in springy, impact type work, which is why the tracker treats running and impact sports as their own category and speaks up when those jump quickly.

None of that is a reason to fear hard training. Tendon problems are load management problems, and load can be managed. The whole game is building up steadily, then trusting the base you have built.

What this tool is not

It is not an injury predictor, because no calculator on the internet can be one. It never sees how you slept, what your week at work was like, your injury history or how your body actually feels. It collects no pain or symptom data at all, deliberately.

What it can do is show you your own pattern, which most people have never actually seen, and teach you what the evidence says about it. If the pattern keeps pointing somewhere awkward, the honest next step is a proper assessment, not a scarier spreadsheet.