In January every coach asks the same question: did the preparation achieve anything? The classic answer is the field test, an hour of freezing around cones, a clipboard full of times and two weeks of discussion afterwards. There is another way. The most meaningful progress data now appears as a by-product, every night and on every run, it only has to be evaluated.
The problem with the single test day
The classic winter test has a built-in flaw: it measures on a single day. Whoever slept badly the night before tests badly although he has improved. Whoever arrives rested tests well although nothing has changed. Add frozen ground, cold muscles and the question whether a December sprint is comparable to a March sprint at all. Field tests keep their place for maximal values like sprint time or jump height. For the actual question of the preparation, whether the engine got better, there is now the more patient route via everyday data.
Resting heart rate and HRV: the engine reports its own adaptation
Endurance training changes the cardiovascular system measurably: stroke volume rises, resting heart rate falls, heart rate variability rises. This adaptation happens over weeks and sits in the sports watch every morning. If a player’s resting heart rate drops by three or four beats over the preparation and his HRV climbs above the old level at the same time, the base work has worked, regardless of how the test day would have gone. What matters is the four-week average instead of single days, because both values fluctuate daily with sleep, stress and the last session.
Running efficiency: metres per heartbeat as a fair progress value
The second silent test hides in every steady run. Divide the metres run by the product of average heart rate and minutes and you get running efficiency: metres per heartbeat. The value answers the core question of endurance, how much distance the body extracts from one heartbeat, and it works for easy and hard runs alike, because the heart rate factors out the intensity. If a player runs five percent further in February at the same heart rate as in December, that is real progress, not test-day luck. The only rules: similar terrain, no fever, and ignore runs under ten minutes.
Three trends become one athletic score
For the squad overview the coach does not need three curves per player but one number. Gearstack computes an athletic score for that: the last four weeks are compared with the four before, in three variables, the HRV trend weighted 45 percent, running efficiency 40 and resting heart rate 15. The result is a value around 50, where 50 means unchanged, 60 roughly two percent improvement across all three variables, and values below a decline. The formula is deliberately documented in the open, because a number the coach cannot explain convinces nobody in the dressing room.
What winter preparation looks like with a squad view
In practice this settles into a simple rhythm. Before the preparation the baseline is recorded, two normal training weeks with a watch are enough. During the preparation the coach checks the development page of the team dashboard weekly: who improves, who stagnates, who drops. The droppers are the interesting cases, because behind stagnation despite training there is almost always one of three things: too much load, too little sleep or a dragged-out infection. At the end of the preparation there is an eight-week answer per player instead of a test day, and the team number above it tells the board in one line what the winter delivered.
Common questions
- Which fitness test makes the most sense for amateur clubs?
- The combination of everyday data over weeks: resting heart rate trend, HRV trend and running efficiency from normal runs. It measures cardiovascular adaptation without a dedicated test day. Field tests remain useful for maximal values like sprint and jump power.
- How fast does resting heart rate improve with training?
- With consistent base work, two to five beats less are realistic after four to eight weeks, more for the untrained, less for the well trained. What counts is the comparison of weekly averages, not single days.
- What is running efficiency and how is it calculated?
- Running efficiency is distance per heartbeat: metres run divided by average heart rate times minutes. If the value rises over weeks in comparable runs, the body extracts more performance from the same heartbeat, which is measurable endurance progress.
For clubs: Eleven players, eleven readiness scores
Sources
Gearstack Health
Your numbers in context
Gearstack Health turns HRV, sleep and training into a daily readiness view with clear next steps.
Gearstack Health is a wellness and prevention product, not a medical device. This text does not replace medical diagnosis, treatment or emergency care.
AI-assisted, reviewed by Kristijan Bezjak, founder of Gearstack.