Progressive overload

Your body always adapts exactly to the load you give it – no more. If you always train the same way, you'll eventually stop making progress. Progressive overload means increasing the challenge in small steps so that the adaptation continues.

There are several dials you can turn, ideally one at a time: the weight (a heavier dumbbell, a stronger resistance band), the repetitions (10 instead of 8), the sets (3 instead of 2), the duration (25 minutes instead of 20), the frequency (three times a week instead of twice), the rest periods (shorter) or the technique (slower, deeper, cleaner). For walking and running, a rule of thumb is to increase your weekly volume by no more than about 10% – a guideline based on experience rather than exact science, but good protection against overuse.

An example for beginners: in weeks 1 and 2, two sets of ten squats; in weeks 3 and 4, twelve; then three sets; then with a backpack. For endurance: first more often, then longer, and only at the very end faster. Keep a record of your progress – a training diary shows improvements that the scales often don't reveal yet.

The key word is “progressive”: small and steady. Jumps that are too big lead to sore muscles, irritated tendons or frustration. Setbacks are part of it too – after an illness, a holiday or a stressful period, you start again one level lower. And every six to eight weeks, an easier week does you good so that your tendons and nervous system can recover.

For children and teenagers, the principle works through play and variety: new climbing frames, longer bike rides, trickier movement challenges. Their bodies grow with it – literally.